Identification?
Monday, May 18, 2020
Case of the Week 591
This weeks case was generously donated by Dr. Michele Bloomer. The following object was removed from the eye socket of an adult patient. According to the surgeon, there were numerous similar-appearing objects present, but only 1 was submitted to the laboratory. About 1 month prior, the patient had undergone surgery to remove his eye as it was involved by a large cancerous growth that had extended from his eyelid.
Identification?
Identification?
That poor man. Looks like dipteran larvae.
ReplyDeleteIt seems most consistent with a larval Lucilia serricata.
ReplyDeleteFor sure a case of myasis. The thin but almost complete peritreme and three straight slits agree with an identification of Lucilia so.
ReplyDeleteFlorida Fan
A verse from one of my favorite poets
ReplyDeleteThe Lord in his wisdom created the fly
But then forgot to tell us why
Ogden Nash
For sure a larva of a Dipteran. Three posterior respiratory slits means it is an L3 larva. There are a lot of genera/species that I can rule out, based on the morphology of the posterior spiracles (not Oestrus ovis, not Lund’s fly, etc), but pinpointing is difficult as my determination keys are not in lockdown with me at home... (not ill, just teleworking)...
ReplyDeleteIt looks like a "classical" case of ophthalmomyiasis due to necrotic, most probably infected tumor around/inside the eye (facultative myiasis), when females of (most probably) Lucilia sericata laid eggs. Apparently, the patient was left long enough without supervision, when the larvae developed to the third instar stage (as said also from the others...three slits). We do not see the anterior spiracula and not the cephalosceleton. The intestine is full of brownish material showing that they were also feeding on blood or decaying necrotic material, which they partially liquefy with their proteolytic enzymes, extracorporially. Allow me to say what I suggest to all physicians and veterinarians in these situation, do not use any toxic chemical or systemic treatment such as ivermectin to kill the larvae. If there are remains of larvae in the deep layers of the tumor/eye, they will decay and cause additional problems to the patient. Use only sterile water, suction and forceps to remove them and do not forget that they will leave the patient anyway (as long as they are alive) in the coming 24-48 hrs to go to a dry place to pupate and later become flies.
ReplyDeleteInteresting case...still a Musca domesticated larva (house fly might have contaminated the cancer if its open) be a chance too!
ReplyDeleteI will go with a case of OcularMyasis
Based on spiracles, I would say that this is the third-instar larva of Phormia sp.
ReplyDeleteAppears to me a L3 larva of Cochliomyia hominivorax. Given the conformation of the spiracles and it´s open peritreme, and the dorsal tracheal trunks.
ReplyDeleteBernardino, I reexamined the case and I see your point. The peritreme is incomplete. You're right.
ReplyDeleteFlorida Fan
Florida fan, i might be wrong since the tracheal trunks are unclear and this can be a Phormia regina larva, as mentioned before. Let´s see.
ReplyDeleteI most humbly request graduate credit for Dr. Mumcuoglu's mini course on qpthalmomyiasis.
ReplyDeleteThis is not ocular or opthalmomyiais; this is facultative myiasis, it just happens to be near the eye. The culprit appears to be Phormia sp., possibly P. regina, but I prefer to confirm these from examination of the specimen.
ReplyDelete