You Better Think! - A three dimensional guideline for recognising the unusual diagnosis in the ill child (including Kawasaki disease)

When assessing ill children, it is easy to presume that the problem is an uncomplicated viral infection.  Most of the time it is.  The odds are severely stacked against a more significant diagnosis to the extent that it is easy to become overly presumptive.  This, combined with the fact that a simple and benign illness will share many features with a rare or dangerous illness means that spotting the unusual or harmful diagnosis is very challenging indeed.

Much of the work done on congitive and diagnostic error takes the errors and then works backwards.  For a long time there have been reports on the number of deaths in healthcare that are related to error. (1)  These are reverse-engineered and start from the point of the problem.  People died - what is the evidence that there was any flaws in the care/ diagnosis/ treatment?  This is very different from the alternative approach of:  People had a healthcare episode- what happened next?

Outcome based stats are dangerous in that respect.  If you have 10% more adverse events than your colleagues but see 50% more patients (because you're awesome at your job) then please come and work with me.  You might flag up as a dangerous clinician if someone looks purely at incidents rather than the big picture.

I think that the most effective clinicians are those capable of recognising well children and capable of changing gear when something is unusual.  This is sometimes referred to as type 1 and type 2 thinking as per the model descibed by Croskerry. (2)

Using this model, we are most efficient when we are thinking inuitively and making gut feel decisions (type 1 thinking) and most effective at making the more complex diagnoses and managing the most dangerous scenarios when we are more considered and thorough (type 2 thinking).

Let's use this example to consider a child with non specific symptoms such as fever, rash, lymphademopathy and pharyngitis.  The reasonable but also dangerous assumption is that the child has an uncomplicated viral illness.  The possibility of another outcome is small but the consequences of missing an alternative diagnosis are great.  So, we need to use type 1 thinking to be efficient and be prepared to go into type 2 thinking when needed.

The obvious questions are then, what am I looking for and when do I look for it?  Guidelines on the subjects of febrile children, URTI in children and recognising complications such as sepsis tend to be written as if the problem was one dimensional or that the same guideline could be used in every circumstance.  This is one of the reasons that guidelines can sometimes frustrate.  Clinicians don't think that way, so it jars when a "fits all sizes" guideline over-simplifies such a complex process.

Here's an example of something that is useful but fairly simplistic.

This tells us what normal and abnormal look like.  It does very little to tellus what it all means.  Stopping here would be fine if we are just going to tell people when to refer or not.  To do that safely, such guidance will invitably err on the side of caution.

What it fails to do is to address what may be causing the red flags or atypical findings.  While a diagnosis is not necessesary in order to make a decision to refer, having a suspected diagnosis helps us to get the right child to the right place at the right time.

Lets take two of the possible complex and dangerous diagnoses as examples.  A child has a febrile illness with conjunctivitis, phayngitis, swollen lymph nodes, a rash and is pretty miserable.  Good to know.  If I told you that the onset of symptoms was within the past 24hrs, would you consider Kawasaki disease? No.  If I told you that it was day 6 of the illness and that for the past 3 days the child was neither better nor worse would you think that the diagnosis was likely to be acute sepsis? No, but can we get a guideline to help us get there?

Since it is a factor in our decision making, we could add in the dimension of time and disease progression to our guideline.  If we did that I think that it could look something like this:

Even adding this dimension doesn't fulfil our need for something which maps to our way of thinking.  We now have the bit that focuses on the child in front of us and the bit that takes into account the real world where patients present in different ways, but many guidelines fail to take into account the fact that different diseases behave differently.  Worse than that, the differences can be subtle.

Guidelines often struggle to deal with the fact that medicine is a complicated subject.  Do you write a guideline for a clinical scenario (e.g. febrile child)?  If so, you need to include every possible cause and when to think of it.  Do you write your guideline about a specific disease (e.g. Kawasaki disease)?  If so, how will people know when to use the guideline?  If they have looked it up, they are 90% of the way there and the guideline is going to be more useful as confirmation and treament advice.

For these reasons, guidelines will never be a substitute for the need for clinical knowledge and understanding.  Our child with non-specific symptoms guideline needs to have another layer - specific diagnoses, what they look like and when to consider them.

We need guidelines to be both simple in order to be practical and complex because nothing is simple.  We need them to be based on real-world clinical practice and to be honest about the uncertainties inherrent to that.

The short answer to the child with non-specific symptoms?  Anything is possible, including Kawasaki disease.  Early recognition of Kawasaki disease is important as treatment will reduce complications.  So, you better think.  In fact, because type 1 thinking will do very nicely most of the time, but not all of the time, you better think think.

Edward Snelson
Occasional overthinker
@sailordoctor

Disclaimer: Over and under-thinking are both perfectly acceptable in the right circumstances.

References

1. Kohn LT, Corrigan JM, Donaldson MS. To err is human: building a safer health system.National Academies Press, 1999.
2. Croskerry P. A universal model of diagnostic reasoning, Acad Med. 2009 Aug

COVID question number 6 - What is hyperinflammatory syndrome and how do I recognise it?

At the same time that we are seeing increasing evidence that COVID-19 is less common, less severe and less infectious in children (1), evidence is emerging of a new phenomenon that seems to be related to COVID-19 infection in children: hyperinflammatory syndrome (2).

In a time when people are being encouraged to self-manage febrile illness at home, and primary care has moved to do more remote assessments, the emergence of such a serious clinical entity is worrying.  Although the number of cases remains relatively small, it represents a significant number of seriously unwell children.  Considering how much we focus on the recognition of sepsis in children, current cases of hyperinflammatory syndrome are being reported in numbers comparable to and possibly greater than numbers of children with severe sepsis.

This does not mean that all febrile children should now have a face to face assessment or that all febrile children should be referred to secondary care.  Like sepsis, it is impossible to recognise an entity like hyperinflammatory syndrome before it is clinically apparent.  There is no predictive test.

Like sepsis, we need to be aware of hyperinflammatory syndrome and recognise it where it is manifest, rather than over-diagnose it to the detriment of children with uncomplicated viral illnesses.  So how do we get that balance right?  The answer lies in recognising what is unusual about the illness rather than focusing on the most common features, since these are not necessarily good discriminators.

First, a few FAQs about hyperinflammatory syndrome in children:

What is hyperinflammatory syndrome?
Like sepsis, definitions of hyperinflammation vary and reflect the fact that it is a clinical diagnosis without a binary test or decision tool.  The published literature reflects an uncertainty about pathophysiology but describes a significant number of cases (20 in North London in less than a month) of children with a similar clinical presentation.  The features have been described as most similar to Kawasaki Disease Shock Syndrome (3), a thing so rare that most of us had never heard of it before this recent surge of cases.

Is it caused by COVID-19 infection?
When the initial reports of cases were being circulated without details, it was unclear as to whether this was simply a case of something happening during the COVID-19 pandemic or because of it.  While no official source has yet declared that COVID-19 is definitely the cause, there is plenty of evidence that this is the case.  First, the numbers are highly unusual (4) and there is a pandemic at the moment.  Secondly, many of the children have tested positive for SARS-CoV-2/COVID-19.  While a small proportion testing positive could be explained by the background rate of COVID-19 in the community, the positive test rate in these cases seems too high.  At the moment the sample size is too small to be conclusisve.  Finally, the demographic of affected children mirrors that of severe COVID-19 in adults, with a predilection for males and BAME children.  It therefore seems most likely that these cases are related to the COVID-19 pandemic.

The hyperinflammation syndrome that is being reposted is thought to be a post-infection phenomenon, rather than a complication of acute infection.  The exact mechanism for this is unclear.  Clinically, it has features similar to Kawasaki Disease (for which the mechanism is unknown) and some overlap with toxic shock syndrome (which is seen in bacterial infection) so we're on the back foot when it comes to working out pathophysiology.

How do I recognise hyperinflammation in a febrile child?
The reported features of the children presenting with hyperinflammation are a mixture of non-specific signs and symptoms with a few more unusual elements that may help the front-line clinician.
While gastroenterological symptoms were common, I would suggest that this information is of little help to a clinician who sees acutely unwell children.  Diarrhoea, abdominal pain and painful swallowing were all common features in children who later developed hyperinflammation but are also frequently found in other viral illnesses.

In the case series reported in the Lancet, tachycardia was sometimes present and sometimes heart rate was unremarkable.  This is somewhat surprising since this hyperinflammatory syndrome seems to affect the cardiovascular system most severely.  It is also consistent with other serious paediatric presentations, where heart rate is one of the least specific clinical signs, being both falsely concerning and falsely reassuring on many occasions.

Tachypnoea, also a common feature occurring when the child presented with hyperinflammation is a more specific feature.  Uncomplicated viral illnesses in children do not tend to affect breathing other than in the form of a transient tachypnoea while febrile.  Unexplained, consistently fast breathing should therefore be considered clinically significant.  This was reflected in the Lancet case series, the majority of whom had tachypnoea.  Note that the cases reported did not tend to have pneumonia, thus the qualifier of "unexplained".  Other explanations for fever and abnormal breathing remain more likely.

The other feature that was most consistent and helpful in discriminating from uncomplicated viral illness was an unrelenting fever.  In children with an uncomplicated viral illness, pyrexia can be dramatic and associated with alarming features such as shivering, cold peripheries, blue lips and mottled skin.  Typically, this is followed by a dramatic improvement, often with the aid of antipyretic medication.

In the cases reported with suspected hyperinflammation secondary to COVID-19 infection, the fever was noted to have been persistently high (38-40 C/ 100.4-104 F) which is much less commonly seen in uncomplicated viral illness.  This may therefore be one of the more useful ways of telling the two apart.

Other features reported include a "variable rash" and painful extremities.  Rashes and pains are common features of uncomplicated viral infection but in combination with the more specific features may help clinicians recognise the syndrome early.

Recognising hyperinflammation (presumed to be related to COVID-19 infection in children) early may therefore be a case of recognising the unusual, looking for alternative explanations such as pneumonia and if no other pathology explains how unwell the child is, looking at how many of the less specific symptoms are present.  If that sounds familiar, that's because it is a similar approach to recognising Kawasaki disease.

The disease then tends to progress to a phase with more significant cardiac involvement, with a profound effect on circulation in many cases.  Shock refractory to fluid boluses is a commonly reported feature.

If signs of shock develop, this will make it more straightforward to recognise that the child does not have an uncomplicated viral illness.  Distinguishing hyperinflammatory shock syndrome from sepsis and other similar presentations brings its own challenges for emergency medicine and acute paediatrics.

Edward Snelson
@sailordoctor

References

1. Munro APS, Faust SN, Children are not COVID-19 super spreaders: time to go back to school Archives of Disease in Childhood Published Online First: 05 May 2020. doi: 10.1136/archdischild-2020-319474
2. Riphagen S., Gomez X., Gonzalez-Martinez C., Wilkinson N., Theocharis P., Hyperinflammatory shock in children during COVID-19 pandemic, Lancet, May 07, 2020 doi:https://doi.org/10.1016/S0140-6736(20)31094-1
3. Kanegaye JT, Wilder MS, Molkara D, et al. Recognition of a Kawasaki disease shock syndrome. Pediatrics. 2009;123(5):e783‐e789. doi:10.1542/peds.2008-1871
4. HEALTH ADVISORY: PEDIATRIC MULTI-SYSTEM INFLAMMATORY SYNDROME POTENTIALLY ASSOCIATED WITH CORONAVIRUS DISEASE (COVID-19) IN CHILDREN, 06 May 2020, New York State Department of Health (NYS DOH) Bureau of Communicable Disease Control (BCDC)

What am I missing? The child with fever but no obvious cause

The fear that a significant illness wil go unreconised in a child is one that is always present for the clinician who sees acutely unwell children.  The stories that we hear of infections and other illnesses being "missed" fuels that anxiety.  The common sense side of us tells us that significant illness should manifest itself in an obvious way, but that doesn't stop us from asking the question, "What am I missing?" when we see a child with a febrile illness and no apparent cause?

Scenario

You have just seen Billy, a 1 year old child with a fever that started today.  They have no cough or runny nose.  They appear well and have a heart rate of 120.  Chest is clear, heart sounds are normal and abdomen is soft.  Tympanic membranes are not inflamed.  You may or may not have looked at their throat but if you did, there is nothing obvious to see.

What do you do?

The answer to this is to understand what the possible causes of fever are, know how to exclude them and have an idea of how likely they are.  The latter brings us onto an important question:

How likely is significant or dangerous infection in a child?

That depends on the child.

The most common risk factor that we encounter is the infant.  The likelihood of an unwell newborn having a significant infection is high.  This is further compounded by their non-specific symptoms and lack of physiological response in the first few weeks of life.  The risk of serious infection multiplied by the risk of underestimating the illness makes a baby under the age of 60 days a high risk patient.

After those first few weeks, the infant becomes less reliant on maternal antibodies and begins to produce a more vigorous response to infection, most of which are now viral.  As a result, the risk diminishes inversely.

Other risky patients are those with ongoing reasons to either have more significant infections or less obvious signs of serious illness.  These include children with neurodisability, immunodeficiency or chronic illness.

For the usually healthy child beyond early infancy, the very great probability is that an illness will be benign and that those infections that are dangerous will manifest themselves in some significant way.  This itself brings a challenge: complacency.  We become so used to good outcomes and fruitless investigations that we start to think that everything is an uncomplicated viral infection.
It usually is, but what if it isn't?  That brings us on to the next question:

What are the less common causes of fever in a child?

One way to think about the causes is within categories:

When there are so many possibilities, it is often best to consider the least common first.  Let's start with the non-infective.  These illnesses cause inflammation without active infection.  They are all very uncommon compared to other things on the list but that makes them easy to forget and therefore miss.

Kawasaki Disease - This is a vasculitis which can look like a prolonged viral illness.  The cause has not yet been identified but it is presumed to be a post-infective phenomenon.  If a child has had a fever for five or more days without a clear cause, we should check if the child fulfils the criteria for Kawasaki disease.  You can check the criteria in a book or use an online tool such as this one linked here.

Leukaemia - Haematological malignancy in children occasionally presents as an unexplained and prolonged pyrexia.  More often there are other symptoms and signs such as increasing lethargy, weight loss, pallor, bruising, bleeding and unexplained pains.

Systemic Onset Juvenile Idiopathic Arthritis (JIA) - this subtype of JIA is rare but is one possible cause of unexplained fever.  Often the fever is accompanied by a typical salmon pink rash and joint pains, even if there is no clinically obvious joint swelling yet.

These non-infective causes of fever should not be over-thought.  The presenting symptoms of childhood illness are often so non-specific that it can be all to easy to imagine zebras instead of horses.  The key to not missing these is to be aware of them as entities and to look for features of these in the child with unexplained fever, especially when that fever is prolonged.

Next, the sepsis question.  Every febrile child should be assessed for sepsis, whether a focus the fever is found or not.  That decision can be made easy for you in one of two ways.  Either the child is very well to the extent that sepsis can be ruled out, or the child is so unwell that sepsis is presumed.  Everything in between is a case of careful assessment, including risk factors and the trajectory of the illness.

So, if we have considered the very rare and the sepsis question, what we should be left with is a child who we think does not have sepsis and yet has a fever without an immediately obvious focus.  At this point we return to the list of possibilities.

The task in a child with fever and no clear focus is to rule these possibilities out, which is usually based on clinical assessment.  Start with the complications of upper respiratory tract infection (URTI) as these are the most common significant infections in children.

Mastoiditis - infection of the mastoid is usually a complication of otitis media infection there should be evidence of that.  Mastoiditis is excluded clinically if there is no erythema, swelling or significant tenderness of the mastoid process.

Peritonsillar abscess - A collection of pus in the peritonsillar tissues is manifested by swelling which displaces the tonsil.  At the time of writing this, throat examination is not routinely performed due to the COVID-19 pandemic.  However, peritonsillar abscess is highly unlikely in a child who is willing to drink or eat.  If the child is refusing all oral intake, it may be necessary to use droplet PPE, including eye protection, to visually exclude peritonsillar abscess.

Lymph node abscess - Inflamed or enlarged lymph nodes are a common finding in children with URTI. Occasionally, the lymph node becomes bacterially infected.  When this happens, the lymph node is more enlarged and painful.  The overlying skin is often erythematous.  Another common feature is that the child becomes reluctant to turn their neck due to the pain from inflammation of the surrounding tissues.  These infected lymph nodes may respond to high dose oral antibiotics, however they may require incision and drainage.  Discussion with or referral to ENT is therefore advisable.

Osteomyelitis and septic arthritis - This is a good example of something that is rare but also often missed when it is a cause of unexplained fever.  Infection in a bone or joint can be visible or hidden.  If a parent has noticed a swollen, red or hot area or that the child has localising signs in a limb, that can lead to early diagnosis.  It is also the case that in a significant number of cases, the infection is not identified early on.  It is no surprise when a febrile child is miserable and moves less.  It is not common practice for clinicians to examine every bone and joint in a febrile child.  However, this is something that needs to be done if a child has an unexplained fever.  If limbs have not been examined for swelling, hot spots or erythema at first presentation, I would suggest that this should be done at the second assessment should fever persist and remains unexplained.

Urinary tract infection (UTI) - UTI is probably the most common cause of fever without a clinically obvious focus in children.  The younger the child, the less likely they are to present with specific symptoms.  Fever without obvious cause is an indication to screen the child for UTI.  Blind treatment with antibiotics is not recommended.  Urine should ideally be sent for culture so that treatment is based on the most robust result - a significant bacterial growth.

Meningitis and encephalitis - Central nervous system (CNS) infection is the most feared of the causes of fever without focus.  In the younger child, symptoms are less specific.  Infants may be irritable, jittery and not feeding well.  Vomiting and excessive sleeping are also common features but again, non-specific.  In an infant with an open fontanelle, this should be examined.  A bulging fontanelle (when not crying) is a red flag sign.  Older children may exhibit classical signs of neck stiffness, headache and photophobia.  Younger children are more likely to stand out because they just won't settle or have an abnormal tone or conscious level.  CNS infection is usually ruled out by the child demonstrating normal interaction or behaviour, often after adequate analgesia has been provided.

Appendicitis - In an older child, recognising appendicitis is done in a similar way to adult practice.  Appendicitis is rare in younger children but when it does occur, it can easily be missed.  Guarding tends to be a later sign in the pre-school child because their abdominal wall muscles are not very strong.  Children often cry or otherwise appear distress when their abdomen is examined, leaving the clinician uncertain.  Analgesia and reassessment is a good way of clinically ruling out appendicitis if the initial assessment is ambiguous.

Pneumonia and empyema - Lower respiratory tract infection (LRTI) is common in children.  Cough and fever are non-specific symptoms and are not grounds for diagnosing LRTI on their own.  Hearing crepitations on auscultation is also a common finding that should not be given too much weight.  Many LRTIs in children are viral and self-limiting.  Important discriminators are how unwell the child is, their work of breathing and more specific focal signs such as localised reduced air entry or a dull percussion note.

Tropical diseases - If a child has an unexplained fever and has recently returned from an area with e.g. malaria, they need to be referred to secondary care for investigation.

And finally...

So if Billy looks well and behaves in a way that effectively rules out sepsis and meningitis, his fever without clear focus means that we should look just a bit harder.  A urine sample should be taken to exclude UTI; blind treatment with antibiotics is not recommended without good evidence of UTI.

If there are reasons to suspect one of the less common (than uncomplicated viral infection) causes of fever, referral to secondary is likely to be the way forward.  If there is no evidence of a significant cause and what you are left with is a reasonably well child with an unexplained fever, the final question is, "should I refer this child or send them home with safety-netting advice?"

Both options are valid and the choice should be made in the best interest of the child.  In secondary care, the assessment of the child should be clinical in the majority of cases.  As such, referral may simply add a further clinical history and examination.  If a second opinion or physical period of observation is felt to in the child's interest, that is fine.  If not, it may be best to keep the child away from hospital and the risks associated with a secondary healthcare setting/

Before a final decision is made, risk should be considered.  For the majority of healthy children presenting to Primary Care (including the Emergency Department) with no specific risk factors, the likelihood of any febrile illness being a serious bacterial illness is very low.  That makes it perfectly reasonable for a child who has had a careful clinical assessment to be managed conservatively and with good safety-netting advice.

There are children who have a significantly higher risk.  As mentioned above, the most commonly encountered risk factor is the baby.  If your patient is a baby, especially if not yet started on their primary vaccinations, fever without focus warrants a referral to paediatrics.

Fever in a child who does not have an immediately obvious focus is a clinical conundrum for all of us.  Many children can be managed with a thorough history and examination.  If there are significant risk factors or specific findings then appropriate referral is likely to be the next step.

Edward Snelson
99% Type 1 decision maker
@sailordoctor

Disclaimer: If it's the clinician who has no focus, there's nothing I can do for you.

Rashes in children: What is the diagnosis? - Probably a virus

A rash is a very common feature of a paediatric presentation and is often the primary reason for seeking medical advice.

I think that clinicians also sometimes feel a bit of anxiety about rashes.  What does the rash mean?  Should I be able to diagnose the illness based on the rash?

The rash can be diagnostic but often it is not.  Even when the rash gives a specific diagnosis, that diagnosis is usually a virus and treatment remains symptomatic and supportive.

These are some important questions to have answers to when assessing a child with a rash.

• Is the child well? If not, how unwell are we talking about and for how long?
• Is the child febrile?
• How did the rash start?
• How has the rash changed since it started?
• Is the rash itchy?

When examining the child, it is important to avoid the temptation to focus excessively on the rash.  The child should have a systemic examination that will identify any cardio-respiratory, abdominal or neurological abnormality.

The rash itself is then in context of an assessment that has determined whether the child is significantly unwell or has any significant abnormal findings.  What this tells us is whether the rash is of importance because the child is quite unwell, or more of interest since the child is well.  In the well child with no significant abnormal findings, a diagnostic rash can still give useful information in terms of prognostication and the ability to give specific advice about what to do from a infection control point of view.

Let’s look at some specific rash related diagnoses that are accompanied by non-specific symptoms such as pyrexia-

Roseola Infantum

What does it look like?

This infection is most commonly seen between the ages of 6 months and 3 years.  The classical presentation is of a significant fever but a surprisingly well child with non-specific symptoms such as coryza and pharyngitis.  Essentially, the child has all the signs of a viral upper respiratory tract infection (URTI) but with an impressive fever.

A macular patchy erythematous rash often appears as the fever starts to resolve.  Typically the rash is more prominent on the trunk than limbs.

What causes it?

Human herpes virus 6

What specific advice is there for this diagnosis?

None.  Treatment is symptomatic.

Chickenpox

What does it look like?

Chickenpox is a vesicular (small fluid filled lesions) rash which is usually found all over the body.  Children are usually either mildly febrile and unwell in the first few days, or not unwell at all.  The rash is often itchy.

What causes it?

Varicella zoster virus

What specific advice is there for this diagnosis? 

There is no specific treatment.  If the child seems unwell then paracetamol (acetaminophen) is the preferred treatment for systemic symptoms.  While there is some concern about using ibuprofen, the evidence strongly suggests that this concern is unfounded.  However, most children do not become significantly unwell with chickenpox and it is unusual for symptoms to require more than paracetamol.  If a child with chickenpox is very unwell, that is a clinical situation that mandates a careful assessment to consider the possibility of sepsis, usually in the form of invasive streptococcal infection.

Itching can be treated with antihistamines.  In the UK, it is usual practice to ask that the child is kept out of school or nursery until day 7 of the rash, at which point new lesions are not forming and the existing spots are crusting.

Hand, foot and mouth disease

What does it look like?

Vesicles on the face around the mouth, ulcers inside the mouth, vesicles on the hands and feet and perianal vesicles or ulceration.  (Somehow the perianal bit got left out when naming this childhood infection)  The child is usually systemically well but when the rash is appearing may be a little miserable and pyrexial.

What causes it?

Coxackie virus

What specific advice is there for this diagnosis?

Treatment is symptomatic.  This is a good opportunity to practice the philosophy of “treat the child, not the fever.  Many children with hand, foot and mouth disease are not febrile but may be in significant discomfort from the oral lesions.  The importance of analgesia to help the child be comfortable enough to drink should be emphasised.

The UK public health advice for hand, foot and mouth disease is that in itself, it does not mandate and absence from school or nursery.

Pityriasis rosea

What does it look like?

The classical pityriasis rosea rash starts with a herald patch in the form of a well localised erythematous area somewhere, usually on the trunk.  This may go unnoticed and if seen rarely causes alarm.  The generalised rash that follows is what usually leads to the seeking of a medical opinion.  This rash is an impressive patchy pink rash with the pattern of the patches following the lines of the dermatomes of the skin on the trunk, forming what is described as a “Christmas tree” distribution.

What causes it?

Human herpes virus

What specific advice is there for this diagnosis?

The child is usually well at the time of the Christmas tree-like rash appearing so no specific treatment is needed.  It should be explained that the rash may last for a few weeks.  There is no need for the child to be excluded from school or nursery.

Slapped Cheek Syndrome (Fifth Disease)

What does it look like?

Most of the features are non-specific: Fever, coryza, sore throat.  The name comes from the typical bright red rash which appears (usually) on both cheeks.  The redness is both more impressive and more consistent than the flushed cheeks seen in febrile children.  This is often followed by a more non-specific, patchy, popular, blanching erythematous rash on the rest of the body.

What causes it?

Parvovirus

What specific advice is there for this diagnosis?

For the purposes of managing the child, treatment is symptomatic.  Most cases of slapped cheek resolve without complications.

A rare but significant complication of parvovirus is an aplastic crisis secondary to the effect of the virus on the bone marrow.   A history of recent parvovirus infection followed shortly afterwards by significant or atypical illness or pallor should prompt the testing of a full blood count.

Parvovirus infection in pregnancy carries a risk of miscarriage or hydrops fetalis (due to the same aplastic crisis).  Parvovirus is not treatable and most pregnant women are immune.  In most places, the advice for pregnant women who come in contact with parvovirus is to seek medical assessment if they subsequently become ill, especially if they develop a rash of any kind.  If serology confirms parvovirus infection then the pregnant woman should be referred to the fetomaternal team.  Through the marvels of modern medicine, it is now possible to transfuse a baby in utero and potentially keep them well long enough to reach a gestation where it delivery is an option.

Measles 
What does it look like?
Typically the child is febrile, coryzal and coughing for a couple of days before the rash appears.  The rash itself is an erthematous maculopapular rash which usually starts on the head before spreading to the rest of the body.
Kopliks spots are diagnostic but rarely seen as they don't hang around for long.  These are small white spots that appear on the inside of the cheeks, opposite the molars.
Measles should be suspected when a child has significant non-purulent conjunctivitis or is particularly miserable despite analgesia.  Unlike uncomplicated viral illnesses, the child is usually quite unwell several days into the illness when the rash appears. (Consider a differential diagnosis of Kawasaki Disease in the child who has had fever for five days as many of the features overlap.  Unlike Measles, early specific treatment for Kawasaki Disease is essential)

What causes it?

Measles virus

What specific advice is there for this diagnosis?
Measles infection requires specific infection control measures and in the UK is a notifiable disease.  There is no specific treatment for Measles and at presentation, the key decision is about how unwell the patient is.  If well enough to be managed at home, it is very important to avoid unnecessary admission to hospital as this might lead to infection of those most at risk.  However if the child is showing signs of significant infection (mainly encephalitis) then admission is probably necessary.  If referring to secondary care it is essential that the accepting team are aware that Measles is suspected so that the child can be kept away from others from the moment of arrival to hospital.

Viral Urticaria

What does it look like?

It looks like an allergic reaction or nettle sting.  The itchy, raised red and white rash can be seen in any part of the body and can be quite alarming.  Typically this rash appears as the illness is getting better.  Lesions appear and disappear several times a day.  If the onset of the rash is accompanied by other symptoms appearing (such as wheeze, oral swelling or vomiting) then acute IgE mediated allergy should be suspected.  Viral urticarial should not be accompanied by the appearance of these symptoms.

What causes it?

One of many possible viruses

What specific advice is there for this diagnosis?

It should be explained that the rash is caused by the virus and the child’s immune system.  The rash doesn’t tell us anything specific about the infection and doesn’t mean anything bad about the illness or the child.   While anthistamines may reduce the itching, they do not seem to make the rash go away any faster.  The rash will usually resolve spontaneously over the space of several days.

It is notable that children who develop viral urticaria are sometimes taking antibiotics when the rash appears.  This can cause concern regarding possible drug allergy.  The evidence suggests that a large number of children developing rashes while taking antibiotics are simply manifesting a viral rash (including urticaria).  This association is contributing to the overdiagnosis of antibiotic allergy.  Many specialists are now advising that a label of antibiotic allergy is not given to a child if they have an acute illness that could be viral, the only symptom is a rash and it is the first time the child has had a rash while taking antibiotics.

Non-specific Viral Rash

What does it look like?

These rashes can appear during the acute infection or recovery phase of the illness.  Typically the rash is a diffuse, patchy erythema.  It may be macular or papular.  In the majority of cases, all of the rash blanches.  Occasionally, a few petechiae can be found.  In a population vaccinated against most strains of meningococcus, a small number of petechiae is most likely to be part of a viral rash.  Indeed, finding one or two petechiae is within normal for a well child at any point. (1)

What causes it?
Any virus that is on the rash B-team could be responsible.  If it's not a diagnostic rash, you can't make a specific diagnosis.

What specific advice is there for this diagnosis?
It's important to explain that the rash doesn't have any specific meaning. For example, a child with this rash does not need to be kept out of school, for infection control reasons at least. Safety-netting advice should mainly centre around the illness, not the rash.  The rash may well persist after the child's illness has resolved.

Many specific rashes start of as non-specific so if the rash changes significantly they may need to be reassessed.  In particular they should know how to assess for non-blanching rash.

Erythema Multiforme

What does it look like?

As the name (What, no Latin?) suggests, it is a rash with multiple forms.  The rash varies from place to place rather than being uniform in appearance.  The rash varies in appearance and texture.  The typical target lesions that also help make the diagnosis are circular and have a dark red centre.

What causes it?
The rash is in many ways very similar to urticaria in children.  It may be a drug reaction but is more commonly triggered by a virus.  That virus is not usually specifically identified.  Atypical bacterial infection, most commonly mycoplasma, may also trigger erythema multiforme.

What specific advice is there for this diagnosis?
Essentially the same applies to Erythema Multiforme as applies to viral urticaria and non-specific viral rashes.  If there is no obvious specific cause, safety-netting for the illness is most important.

Because Erythema Multiforme can rarely progress to Stevens-Johnson Syndrome, it is worth advising the family to seek reassessment if the child develops an inflamed mouth.

Henoch-Schonlein Purpura (HSP)
What does it look like?The typical HSP rash is a purpuric rash on the lower limbs, predominantly on the buttocks and extensor surfaces.  This is often fully apparent at presentation but sometimes the initial rash is not purpuric.  In some cases other symptoms precede the rash.

Typical symptoms of HSP include leg pains and abdominal pains, though in some cases HSP is asymptomatic.

What causes it?
The cause is unknown, however it is presumed that this vasculitic process is triggered by infection.  In that sense, it can be considered a viral rash.

What specific advice is there for this diagnosis?
Most cases of HSP are suitable for outpatient management and in many cases this is well within the remit of the General Practitioner.  A full explanation of the condition, possible complications and how to manage/ followup can be found here.

Bringing it all together
So there you have it - a reasonably comprehensive list of common rashes seen in childhood infections.  In most cases, the rash will not give a specific cause.  In every case, the clinical condition of the child is by far the more important part of the assessment.  After all, it's probably a virus and you probably can't treat that.

Edward Snelson
Rash decision maker
@sailordoctor

Disclaimer - it might not be.

References

1. Downes AJ, Crossland DS, Mellon AF Prevalence and distribution of petechiae in well babies Archives of Disease in Childhood 2002;86:291-292.

Making the Right Judgement - a comprehensive 3D model for deciding what to do with each child with a respiratory presentation

In the previous post, I covered how best to make a diagnosis of lower respiratory tract infection (LRTI).  Anyone who has the pleasure of working with acutely ill children knows, the diagnosis is only a small part of what we do.  A big part of what we do is making that all important decision - home or hospital?

This decision is usually made up of several elements.  What is interesting is that the same principles can be applied to all of the major respiratory problems that we see, namely:

• Bronchiolitis
• Viral Wheeze
• Asthma
• Croup
• Pneumonia (LRTI)

Once one of these diagnoses has been made, the decision about whether to admit or manage at home is a huge one.  On the one hand, we don't want to admit children to hospital unnecessarily.  Apart from the inconvenience and stress to the family, there is a significant risk of adding insult to injury as so many children who attend hospital acquire additional infection.  On the other hand, we know that if a respiratory problem does deteriorate, it can do so quickly and catastrophically.  If there is a significant risk of a child going off, they should be somewhere that can respond appropriately.

In the majority of childhood respiratory illnesses, the treatment itself is not what requires the child to be in hospital.  It is no longer routine to have a chest X-ray and intravenous antibiotics for uncomplicated community acquired pneumonia. (1)  Many children who are admitted with pneumonia receive no investigations and are treated with oral amoxicillin and discharged when they show improvement.  Severe croup is often a waiting game.  Viral wheeze is usually treated with inhalers via spacer.  Babies with bronchiolitis are often observed while a team of expert paediatricians avoid the temptation to "try something" that research has proven to be pointless.  You get the picture.  These are the times that paediatrics is the art of masterful inactivity.  Believe me, that is harder than it sounds and is actually quite labour intensive when done properly.  The point is, they still need to be there, because these are the children who, if they got worse, would require escalation of treatment.

So if the need for hospital specific treatment isn't always the thing that determines the need for admission, what else is?  In illnesses that always need hospital treatment (e.g. Kawasaki Disease) the decision is made for you.  However in respiratory problems that can be treated in the community, the decision is mostly about risk assessment, which is never as simple as people make it sound.

Guidelines often imply that the assessment of a respiratory presentation is a simple matter of deciding severity or calculating a score.  I like an over-simplification as much as the next clinician, except when it doesn't work, which is fairly often.  Why isn't it that simple?  Because not a one dimensional assessment.  The good news is, it's not that complicated,  It's just 3D instead.

D1 - Severity

The first dimension of the assessment is to decide severity.  All acute respiratory problems, like chain coffees, come in small medium and large.  Deciding which presentation fits into mild moderate or severe is fairly intuitive and the same principles apply across the different diseases.

Severe makes the decision easy.  Severe needs to be treated in hospital for several reasons.  Severe is usually a set piece, and although severe can be terrifying, it's not usually a cause of decision fatigue.  That comes from deciding what to do with the rest of them.

In a previous post, I shared some thoughts on croup scores and severity.  You can read that via this link if it would be helpful.

Mild cases of croup, bronchiolitis, viral wheeze, asthma and LRTI are almost always best managed at home.  Almost.  Moderate cases can often go either way.

D2 - Risk factors

This means that other factors are involved in the decision.  Because we are assessing risk, we need to consider risk factors.  These, when applied to the severity of the illness literally multiply the risk of something bad happening.

As a rule, a risk factor alongside a moderate severity of respiratory problem is ore than enough to mandate admission to hospital.   That child with croup that you were thinking of sending home- I suspect that decision will be changed when you factor in the fact that they were born prematurely at 26 weeks.

What is slightly more complicated is how risk factors apply to the child with a mild presentation.  It's complicated because the presence of a risk factor does still ramp up the risk, but its a factor applied to a very small risk in the first place.  What's more, the same risk factors that apply to the presentation also apply to the risk of being in hospital.  An ex-premature baby with mild bronchiolitis could go off, but the risk is still small.  An ex-prem baby in hospital if they don't need to be is a risk all of its own.

The decision about what to do with a child who has a mild respiratory problem but also has risk factors is a difficult one.  It is a decision best made by an experienced clinician who understands the way that the particular risk factor interacts with the illness and knows the pitfalls associated with it.  If you're not sure, refer or discuss the case.  This may be a good opportunity for an experienced primary care clinician to share that decision with an experienced paediatician via a telephone consultation.

D3 - Red Flags

Finally, there are red flags.  Although independent of the apparent severity of the presentation, these features will usually mandate referral or admission.

A good example of a red flag feature would be a 4 month whose clinical examination is consistent with mild bronchiolitis.  If the accompanying adult says that the infant had an episode of suddenly becoming pale and floppy earlier that day, this should be treated as a warning sign.

Bringing those three dimensions together will give you the answer to the "home or hospital?" question.  It will also help the communication between primary and secondary care.  Referring a child with a respiratory problem, summarised as diagnosis, severity, risk factors and red flags is just showing off.  There's nothing wrong with that is there?

Edward Snelson
Dimensional Relativist
@sailordoctor

Disclaimer: I'm never sure which is worse: oversimplification or undersimplification.

References

1. Guidelines for the management of community acquired pneumonia in children: update 2011 British Thoracic Society Community Acquired Pneumonia in Children Guideline Group

Where is Your Focus? Let's Play Spot the Ball.

I think that the hunt for a focus of infection in a child is a lot like a game called “Spot the Ball” in which people looked at a picture from a football game with the ball removed and tried to guess where the ball was.

Finding a focus of infection is a very interesting topic at the moment.  More than ever, primary care clinical assessments are occurring remotely rather than face to face. Febrile children are being assessed without laryngoscopy or auscultation.  This seemingly contradicts the tradition of the need to find a focus of infection.  So what is the deal?  I've been asked a lot of questions about this recently and I thought that the simplest thing to do was to bring together my answers.

Do I need to find a focus of infection?

No.  There is no absolute need to find a focus of infection.  Here are a few facts that disprove the idea that a febrile child needs a physical clinical assessment for focus of infection in every case:

• If finding a focus was mandatory, parents and carers would have to have their febrile child assessed on every occasion.  Self-care without medical assessment would be neglectful and therefore a safeguarding issue.
• Even if you believe that medical assessment should take place, this only provides a snapshot.  Childhood febrile illnesses are dynamic and the focus can change.  A child who has an otitis media now could have mastoiditis before the day is over.  If we always need to know the focus, you would never be able to send the child out of your sight.

Does finding a benign focus rule out serious infection?

No.  That’s not how that works.  To illustrate the point, I'll tell you a story.  A 4 month old child came in with a history of fever and irritability progressing to vomiting and unresponsiveness.  On assessment they had a GCS of 8, heart rate of 200 and capillary refill time of 4 seconds.  I looked in their ear, found that they had otitis media.  We all celebrated the finding of the focus and discharged the patient with oral medication. 

That would never happen of course.  While I give that as an ridiculous example, the principle does apply to the moderately unwell child also.  Finding a focus can be a distraction or a premature conclusion.  If we are misled into thinking that an upper respiratory focus is the end of the decision making, we're missing a bigger picture.  We still need to step back and look at the overall clinical scenario.  So in the need to rule out things like meningitis, sepsis and pneumonia, finding a focus could be diagnostic noise.  Serious infections are ruled out on their own merits, not by finding another focus.

Does a runny nose count as a focus of infection?

Yes, but the question of infection doesn't work like that.  A child with a runny nose and a non-specific cough can be presumed to have an upper respiratory tract infection. The real question is, do they have features of another more significant focus?  If they have difficulty breathing, are seriously unwell or specific features of something else (e.g. reduced conscious level) then the assumption flicks from "presumed uncomplicated URTI" to "presumed complication of URTI".

One of the values of giving credibility to non-specific respiratory symptoms is that it helps to answer the age-old question of "should I get a urine sample from this child?"  That's a whole new can of worms.  In a massively oversimplified answer, if they are well and have a cough and runny nose you don't need one.  If they have no cough or runny nose you do need one, especially if they have abdominal pain, vomiting without diarrhoea or have strong smelling urine.

So if focus can be misleading and can change soon after I've assessed it anyway, what am I actually supposed to be doing? 

Treat the assessment of an unwell child like a game of spot the ball.  There will be clues and distractions.  There will be things that direct and misdirect.  The main task is to look for signs of a focus that needs to be treated.  Uncomplicated upper respiratory tract infection (including tonsillitis and otitis media) are not on the list of things that must be identified and treated.  What is interesting is that uncomplicated lower respiratory tract infection’s (LRTI/ pneumonia) place on the list is increasingly in question.

What is on the list of significant infections and how do I detect these?

• Complications of URTI are rare but significant.  Externally, mastoiditis and lymph node abscess can be detected clinically.  Internally, peritonsillar abscess should be looked for in a child who is unable to swallow despite adequate analgesia.
• Central nervous system (CNS) infection (meningitis, encephalitis, abscess) disproportionately affect function and behaviour.  Reduced or focally abnormal CNS function is a red flag.  Signs and symptoms are often non-specific in children but the non-specific signs such as inability to settle are persistent in a way that is unusual for uncomplicated infections.
• Pneumonia, when accompanied by significant respiratory distress or systemic effects is still going to be on the list.  The fact that there is mounting evidence that pneumonia without significant effects does not mandate treatment simplifies the assessment of focus.  Localised signs on auscultation is a focus but the need for antibiotics in the absence of more significant findings is questionable.
• Urinary tract infection is a paradoxical focus in children.  While UTI can self resolve without significant likelihood of complications, these low grade infections often go undetected.  The UTIs that are clinically apparent in children are the most severe UTIs.  It is therefore normal to treat all UTIs especially in pre-school children.  Urine samples should be tested if there is no clear focus elsewhere.  In the child under three years old, ideally these samples are sent for microscopy and culture.
• Finally, there is the focus that is not actually infection.  Inflammatory diseases such as Kawasaki and PIMS-TS present with 5 or more days of unrelenting fever, mucousitis and a very miserable child.  Consider this possibility when the child is worse or no better on day 5 of a febrile illness.

When you play spot the ball in the traditional way, you don't get to find out if you were correct until the next day.  What could be more like hunting for the serious focus amongst the hundreds of febrile children you will see or assess remotely this year?

Good hunting.

Edward Snelson

@sailordoctor