Belly button mystery

A healthy 17 yo male presents with a 1st episode of peri-umbilical progressive pain for the past 3 days.  No nausea or vomiting; Normal stool; Unconfirmed fever.  Slight discharge from umbilicus for last 24 hours.

Referred by clinic to R/O incarcerated hernia.

Examination of the abdomen demonstrated peri-umbilical redness and pain. No mass. No guarding or rebound.

Naturally point of care ultrasound is applied.

So what’s the diagnosis?

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 Hint: Remember your embryology!

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If you answered infected urachal cyst and your name is Brett, then you get to say “Check out the big brain on Brett” after which you should go and watch Pulp Fiction a few more times while pretending you are as cool as Samuel L. Jackson.

Urachal cysts are most commonly found in the pediatric population as the urachus usually regresses in early infancy.  Infected cysts are the most common presentation of urachal abnormalities in adults.  They carry a risk of malignant transformation if not removed.  Treatment usually includes drainage of the cyst with a course of antibiotics followed by later surgical excision of the urachal remnant.

Here’s a nice review article by Ekwueme and Parr: