Wednesday 8 January 2020

Something or nothing - why topical antibiotics are not for neonates with eye and umbilical infections

Newborn babies cause clinicians a lot of anxiety.  The worry about infections can lead to the use of antibiotics "just to be safe."  This is usually not the best approach.  Most of the time, the symptoms are nothing, and when they are something more significant, sending the baby home with topical antibiotics is not the solution.

Let's look at two common scenarios.

Scenario 1 - The baby with a sticky eye

A one week old presents with a unilateral sticky eye.  The baby is otherwise well, feeding and growing.   The left eye has a yellow discharge around the margin of the eyelid.  The baby's examination is otherwise normal.

What's the problem?  Something or nothing.

The nothing problem is the more common scenario.  Many babies are born with a non-patent nasolacrimal duct.  The inability to drain tears from the eye to the nose leads to the sticky eye.  Tears are made up mainly of water and lipid (for lubrication).  The water mostly evaporates leading to a thick secretion which accumulates.  This is not a sign of an infection.

Most blocked tear ducts will self-resolve over weeks or months.  It is unusual for them to persist until the infant's first birthday.  If it does, an ophthalmologist can unblock the duct with a probe.

Rarely, there will be a cystic collection in the tear duct.  This presents with the same sticky eye but with a swelling visible at the inner canthus of the eye.  There are some good pictures of what that looks like here.  Although these do sometimes self resolve, dacrocystoceles can be problematic and should be referred to an ophthalmologist.

The something problem is infective conjunctivitis, but not as you know it in older children.  Babies have all those lovely maternal antibodies to protect them from common viral infections, so viral conjunctivitis is relatively rare in newborns.  In addition to the increased likelihood of bacterial infections, there are two other factors that make topical antibiotics a bad idea for newborn eye infections.

Firstly, the infection may be congenitally acquired.  Chlamydia and gonorrhoea are two organisms that cause bacterial eye infections in neonates.

Secondly, the baby's immune system is heavily reliant on the aforementioned maternal antibodies.  Their own immune system is immature and relatively unresponsive.  That is one reason why newborns have vague symptoms during serious bacterial infections, while a one year old has a temperature of 39C and can look really unwell with an uncomplicated viral illness.

If this baby does have a bacterial eye infection, it is high risk both for the eye and the baby.
Opthalmia Neonatorum - from the Centers for Disease Control and Prevention's Public Health Image Library #3766

As a result of all of these factors, eye infections in newborns (ophthalmia neonatorum) should be taken seriously and referred for acute assessement and management by paediatrics or ophthalmology depending on your local pathways.

How do I tell the difference between the something and the nothing?

It's actually quite simple.  There are a few quick things to check:
The answers to these questions give you the answer to what you should do next.
While it might feel like the safe option to just give topical antibiotics to every baby with a sticky eye, this is not the case.  If the problem is a blocked tear duct, the eye drops may cause a chemical conjunctivitis and make things worse.  If the problem is an infection, it is higher risk for the eye and the baby and so needs careful assessment and management.

Scenario 2 - The baby with red skin around the umbilical stump

A three day old baby is brought to you by one of their parents.  There is some redness around the umbilical stump.

What is the problem?  Something or nothing.

The nothing option if the umbilical stump is still attached is non-infective inflammation.  From the moment of birth, the umbilical stump is devitalised tissue.  In the absence of a blood supply, it goes through a process that leads to separation, usually about a week or two after birth.  During this time it can either just become dry and shrivelled or it can become a bit sticky and smelly.  Often, the skin around the base has been repeatedly cleaned to remove any stickiness.  This itself can cause a small halo of red skin.
Image taken from the Stanford Newborn Nursery site and used with permission. This material was compiled by Janelle Aby, MD for educational purposes only.  Reproduction for commercial purposes is prohibited.  Utilisation of the materials for educating those who care for newborns is permitted with proper citation of source.
The nothing option if the umbilical stump has separated is an umbilical granuloma.  These benign growths are quite common and will self resolve.  They have a tendency to produce some exudate.  Again, repeated cleaning can cause a bit of inflammation to the surrounding skin.

The something scenario is omphalitis.  Infection of the umbilical stump carries a high risk of invasive infection.  This of course is partly due to the immunology of a newborn (see above).  It is also because the umbilicus retains its connection to the circulation.  The external part may be dead but the vessels inside are still patent and may help to seed the infection systemically.
Image taken from the Stanford Newborn Nursery site and used with permission. This material was compiled by Janelle Aby, MD for educational purposes only.  Reproduction for commercial purposes is prohibited.  Utilisation of the materials for educating those who care for newborns is permitted with proper citation of source.
Omphalitis is now a rare occurrence in the UK and other similar counties.  It remains a more frequent presentation in countries with limited healthcare resources, especially where it is common to give birth in unclean environments.
Since most of these neonates will be cared for in a hospital setting, babies that present to GP or ED are likely to be low risk.

In a low risk baby, the decision about what to do is fairly straightforward.
While it might feel like the safe option to just give topical antibiotics to every baby with a sticky umbilicus, this is not the case.  If the problem is non-infective inflamed skin, applying chemicals is only likely to make that worse.  Inflamed and broken skin does not make a good barrier to infection.  If the problem is an infection, it is a high risk situation best managed in a secondary care setting.

So if it's nothing, leave it alone.  This of course always requires good safetynetting advice.  If it is something significant, this is usually best managed in a secondary care setting.  There's no real role for the practice of doing something to make us feel like we've done something.

Edward Snelson
Cautious binarian
@sailordoctor