BREATHITT VETERINARY CENTER DIAGNOSTIC ROUNDS


Digesting a case of Cryptosporidiosis Clenon G. Hendricks, DVM, MPH


Assistant Pathologist, Assistant Professor Murray State University Breathitt Veterinary Center


A 20 gram kingsnake (Lampropeltis getula) maintained in a warm room (per breeder) was found dead in its enclo- sure after a brief history of vomiting and abdominal bloat. Te animal was presented to the referring veterinarian two days later for evaluation. Tis was the second of the breeder’s nine snakes that died.


Te animal presented in poor postmortem preservation. On gross examination, the stomach was distended by gas and devoid of gastric contents. A direct smear of the gastric mucosa was obtained and submitted for carbol-fuchsin acid fast staining, which revealed numerous oocysts consistent with Cryptosporidium spp. Gross diagnoses were moderate diffuse gastric distention and generalized marked autolysis.


Samples of the liver, esophagus, stomach, intestines and colon were collected, fixed in 10% buffered neutral formalin, routinely processed and stained with hematoxylin and eosin for histologic examination. On histologic evaluation, forty percent of the faveolar spaces of the lung were collapsed and several faveoli contained moderate amount of fibrillar eosinophilic proteinaceous material. Marked autolysis hindered interpretation of changes within the liver, esophagus, stomach, intestines and colon. Histologic diagnoses consisted of moderate broncho- pneumonia with foreign material and marked autolysis.


Given the cytological finding of Cryptosporidium oocysts from the carbol-fuchsin stain of the gastric mucosa, a distended stomach on gross examination, and a history of abdominal bloat and vomiting, the final diagnosis was gastric cryptosporidiosis with severe gastric distention.


Discussion: Cryptosporidium spp. are apicomplexan parasites that affect a variety of animals including, avian, reptiles, and mammals. Infection by Cryptosporidium spp. has been reported in 57 species of reptiles, predominantly snakes and lizards2


. Although these organisms affect the gastrointestinal tract of reptiles, Cryptosporidium spp. has also been found in extra-intestinal sites such as ears of green iguanas (Iguana iguana).3


Currently, the four species


known to cause disease in reptiles are: Cryptosporidium serpentis, Cryptosporidium varanii, Cryptosporidium testu- dinis, and Cryptosporidium ducismarci.1


stomach, while C. varanii and C. ducismarci usually affects the intestines.1,3,4,5,6


A pathogen of snakes, C. serpentis causes mid-body or abdominal swelling and non-specific gastrointestinal symptoms due to mucosal hyperplasia, excessive mucus production and poor digestion.1,4


In the majority of


cases, prognosis is poor. A combination of quarantine, environmental monitoring and disinfection are the best prevention and control methods to recommend for breeding or multi-reptile settings.


Not all snakes infected with C. serpentis present with clinical disease1 ; however, several factors, including stress or concurrent disease might cause infected animals to present with clinical symptoms due to immunosuppression.1,6


Transmission of infective Cryptosporidium oocysts can occur directly through the fecal-oral route or predation, or indirectly via contaminated enviroment.1


After ingestion, the infective oocysts release sporozoites that infect


cells of the gastric mucosa. Following several stages of asexual reproduction within the host cells , the organism begins sexual reproduction with eventual production of oocysts, which may either infect adjacent host cells or shed into the environment through feces.1,6


becomes inflamed, gastric glands dilate, the amount of fibrous connective tissue increases in the lamina propria, and mucus production increases.1,4 cur.1


During the reproductive phases of C. serpents, host gastric mucosa Narrowing of the gastric lumen and gastroduodenal intussusception can oc-


Histologically, the organisms can be seen on the apical surface of the gastric mucosa.2,4


Polymerase chain reaction and immunofluoresecent (monoclonal) antibody testing (IFA) are the best tools to differentiate cryptosporidium species.1,6 technique to detect C. serpentis.1


Endoscopic biopsy of the gastric mucosa has been reported as a sensitive 28 KVMA News - Diagnostic Rounds


Diagnostic tests offered at BVC that can be performed in pre or post mortem Continued on pg. 29


In their preferred hosts, C. serpentis and C. testudinis usually affects the


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