September 2018

Signalment (JPC #1622313):  Male boa constrictor

HISTORY:  This pet snake developed diarrhea that was unresponsive to ampicillin.

HISTOPATHOLOGIC DESCRIPTION:  Stomach, glandular portion:  Diffusely the gastric mucosa is thickened up to 2mm, forming papillary and frond-like projections (hyperplasia).  There are increased numbers of mucous cells that often separate, compress and replace gastric glandular epithelium (mucus hyperplasia and metaplasia).  Lining apical and luminal epithelium and free within the lumen are numerous 2-6 um diameter, round, pale amphophilic to basophilic protozoa with variably distinct 1-2 um basophilic nuclei.  Multifocally the lamina propria contains small numbers of lymphocytes, plasma cells and fewer heterophils.  Diffusely, gastric glands are separated by clear space and multifocally lymphatics are ectatic and contain an eosinophilic, amorphous substance (edema).  Occasionally gastric glands are distended by sloughed epithelial cells, cellular debris and few basophilic, 1 X 6 um bacilli.

MORPHOLOGIC DIAGNOSIS:  Stomach:  Gastritis, proliferative, chronic, diffuse, marked, with mucus neck cell hyperplasia and metaplasia and numerous free and apically attached protozoa, etiology consistent with Cryptosporidium sp., Boa constrictor (Boa constrictor), ophidian.

ETIOLOGIC DIAGNOSIS:  Gastric cryptosporidiosis

CAUSE:  Cryptosporidium serpentis

Signalment (JPC #3103340): 4-year-old intact male rhesus macaque

HISTORY: Animal was CD8 depleted, treated with anti-IL-15 monoclonal antibody and infected with simian immunodeficiency virus (SIV) to study CD4-T cell kinetics. Months after infection, animal became lethargic and anorexic with weight loss.

HISTOPATHOLOGIC DESCRIPTION: Bile duct, extrahepatic: There is circumferential biliary epithelial hyperplasia, characterized by piling up of epithelial cells with formation of prominent villar-like papillary projections which extend into the lumen. The mucosal epithelium ranges from cuboidal to columnar with large, prominent vesiculate nuclei, increased mitotic figures (up to three per HPF) and scattered apoptotic cells. Goblet cells are increased in number and multifocally replace epithelial cells (goblet cell hyperplasia and metaplasia).  Lining the apical and luminal epithelium and free within the lumen are multiple 2-6 um diameter, round, pale amphophilic to basophilic protozoa with variably distinct 1-2 um basophilic nuclei.  Multifocally the lamina propria contains moderate numbers of lymphocytes, plasma cells and fewer histiocytes and eosinophils admixed with mild hemorrhage which extends multifocally into the adjacent mesentery. There is mild periductal fibrosis.

MORPHOLOGIC DIAGNOSIS: Bile duct: Cholangitis, proliferative, chronic, circumferential, moderate, with goblet cell hyperplasia and metaplasia, periductal fibrosis and apical protozoa, etiology consistent with Cryptospordium sp., rhesus macaque (Macaca mulatta), nonhuman primate.

ETIOLOGIC DIAGNOSIS: Biliary cryptosporidiosis

CAUSE: Cryptosporidium sp.







hypertrophy and hyperplasia of crypt epithelium






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