Blackwell's Five-Minute Veterinary Consult: Reptile and Amphibian. Javier G. Nevarez

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       Examination of feces: unstained smears are useful but sensitivity of detection increases with an acid‐fast stain and is greatest with an IFA stain.

       Sensitivity may be increased if performed postprandially.

       An important limitation of these tests is their lack of specificity to differentiate Cryptosporidium spp.

       False positive results can occur in animals that have ingested food items (i.e., mice) infected with other Cryptosporidium spp. that are not pathogenic to reptiles.

       Serum antibody titers: can be assessed using an ELISA but antibodies take 6 weeks to develop. Best if combined with fecal or gastric lavage.ELISA positive, fecal positive—animal infected and shedding.ELISA negative, fecal negative—not infected.ELISA negative, fecal positive—recent infection (<6 weeks) or passing non‐reptilian Cryptosporidium spp.ELISA positive, fecal negative—has been infected at some point but not shedding or shedding at undetectable levels.

       PCR: a highly sensitive test that can be used for either fecal or lavage samples. Can also differentiate between Cryptosporidium spp.

       Gross: intestinal lesions may include mucosal thickening with mucus accumulation.

       Histopathology: intestinal lesions consist of a mixed inflammatory response with up to 80% of epithelial cells containing parasites.

       Force‐feeding with easily digestible proteins.

       Direct feeding by stomach tubing can be performed in some species; placement of an esophagostomy tube should be considered for chronic management.

       Supportive fluid therapy should be provided.

       Clients should be made aware of the insidious nature of infection, the unlikelihood of successful treatment, the risks that affected animals pose to the remaining collection, and the known zoonotic potential of some species of Cryptosporidium.

       Cryptosporidium oocysts are hardy and can persist in the environment for long periods, so thorough cleaning and disinfection is important.

       Methods for disinfection include:ammonia (5%) or formal saline (10%) solution contact for 18 hoursexposure to moist heat (45–60 degrees C) for 5–9 minutesfreezingthorough desiccation alone, or after any chemical application

       Trimethoprim sulfonamide 30 mg/kg PO SID for 14 days, then 1–3 times weekly for 3 months may reduce oocyst shedding but does not eliminate cryptosporidium organisms from the gastrointestinal mucosa.

       Paromomycin 100 mg/kg PO SID for 7 days; then twice weekly for 6 weeks; and 360 mg/kg q48h for 10 days resulted in complete resolution in experimentally infected bearded dragons (Pogona vitticeps).

       Hyperimmune bovine colostrum 1% body weight by volume PO once weekly for 6 weeks. Currently not available commercially.

       Euthanasia should be strongly considered for affected animals to limit spread.

       If euthanasia is not an option, diseased reptiles should be separated from the remaining collection and strict barrier nursing protocols enacted to prevent spread.

       C. pestis is a known zoonotic risk; C. ducismarci shows genetic similarities to other zoonotic Cryptosporidium spp.

       Caution should be used when working with suspected cases.

       ELISA = enzyme‐linked immunosorbent assay

       IFA = immunofluorescent antibody

       IM = intramuscular

       IV = intravenous

       PCR = polymerase chain reaction

       PO = per os

       SC = subcutaneous

      1 Cranfield MR, Graczyk TK. Cryptosporidiosis. In: Mader DR, ed. Reptile Medicine and Surgery. 2nd ed. St. Louis, MO: Elsevier Saunders; 2006:756–762.

      2 Fayer R. Taxonomy and species delimitation in Cryptosporidium. Exp Parasitol Jan 2010; 124(1): 90–‐97.

      3 Fayer R, Graczyk TK, Cranfield MR. Multiple heterogenous isolates of Cryptosporidium serpentis from captive snakes are СКАЧАТЬ