Microscopic description and IHC:

Bacterial tetrads are seen in the lumen of the specimen. The tetrads are basophilic, large and do not appear to have an underlying effect on the gastric mucosa, which otherwise appears unremarkable.

Discussion:

Sarcina spp. are associated with delayed gastric emptying (as found on EGD in this patient). Although they are not linked to adenocarcinoma or ulceration, they are not harmless. In addition to being a marker of delayed gastric emptying, Sarcina are gas-producing microorganisms and can give rise to emphysematous gastritis and possible perforation.

References:

Sarcina organisms in the gastrointestinal tract: a clinicopathologic and molecular study. Lam-Himlin D, Tsiatis AC, Montgomery E, Pai RK, Brown JA, Razavi M, Lamps L, Eshleman JR, Bhagavan B, Anders RA. Am J Surg Pathol. 2011 Nov;35(11):1700-5.

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