This can definitely be filed under the rare and obscure portion of EM. But i’ve seen it twice in 12 years, and was baffled both times so there you go…
- known as hyatid disease (definitely easier to spell) or echinococcus (and the bunny men) granulosum
- It’s a parasite duh
- Mainly acquired in the developing world from poo of course. Always the poo… (Update, my former Colleage, Dr Adler, an ID chap pointed out in the comments that’s faecoral from the animals – not the humans. We’re “dead end hosts”)
- Primary infection always asymptomatic and usually in childhood
- Clinical presentation is usually later (up to 50 years). You will see this (as I recently did) given increased immigration
- Symptoms are usually related to mass effect in the affected organ so they can be fairly broad
- Liver the commonest organ so it’s the type of thing you might see either incidentally or pathologically with your bedside ultrasound
- They can rupture and cause all kinds of funky spread
- Cysts can become calcified and appear clearly on plain films
- Important to stop your radiologist trying to biopsy one as they can precipitate spread or even anaphylaxis
- Diagnosis is usually a combination of imaging and serology
- Management depends on whether there are complications from the cyst or not.
- The more complicated it is the more likely surgery will be needed.
- If you just want to treat the parasitises then reach for the ever faithful albendazole.
- as always if you want some cool images click through for what Google has to offer
- Rosen’s 8th Chapter 133