CLINICIAN’S NOTEBOOK 5-minute Guide to Disease

MADS BERTELSEN ■ GRAHAM CRAWSHAW

THE AMPHIBIAN PATIENT IS mammography units. Ultrasonogra- often presented late in the disease phy may help identify coelomic process, and the presenting signs are masses or fluid accumulation and commonly limited to anorexia, weight assist in guiding transcutaneous loss and/or fluid retention. A review aspiration or biopsy. Laparoscopy, of the husbandry and feeding history using a small fiberoptic arthroscope, should be part of any workup. Diag- offers internal visualization. nostic information may be obtained in Careful post mortem examination of a manner similar to that used with diseased specimens followed by other vertebrates, although the small histopathologic examination is crucial size of many patients limits the quan- in diagnosing and treating problems tity and usefulness of diagnostic affecting several . Common samples. Mads Bertelsen, DVM clinical manifestations, selected [email protected] Thorough physical examination may differential diagnoses and diagnostic Veterinary Resident reveal fractures, impactions, swellings, options are presented in Table 2. Zoo/Wildlife Medicine and Pathology masses, fluid accumulations or skin Graham Crawshaw, BVetMed, Once a tentative or final diagnosis has and eye abnormalities. Blood can be MRCVS, Dipl ACZM been made, may be collected from peripheral superficial Toronto Zoo subjected to standard surgical and Scarborough, Ontario veins, but collection is generally more medical treatment. Amphibians have Canada reliable from the heart. Although low metabolic rates but high rates of [email protected] hematologic and biochemical values fluid turnover, placing them between vary and only limited normal values mammals and in the pharma- are available, analysis of the blood cokinetic spectrum. Oral, subcuta- sample may offer important diagnos- neous and topical/transcutaneous are tic clues. Fresh feces should be exam- Table 1. Common Drugs the most common treatment routes. ined for the presence, identification, Successfully Used in Amphibians and number of protozoan and meta- Adult amphibians are carnivorous, zoan parasites and ova. Analysis (e.g., and nutritional support may be pro- Fenbendazole or Nematode moxidectin/ infections cytologic evaluation and assessment vided by tube feeding commercially ivermectin of total protein content) and culture of available cat foods or formulas. Fluid Metronidazole Protozoan coelomic and subcutaneous fluid therapy may be accomplished by infections should be pursued in the presence of placing the in a shallow pool Enrofloxacin, Bacterial fluid accumulation. Skin scrapings, of clean water or, for more immediate amikacin or infections exfoliative cytology, fine-needle aspi- effect, by subcutaneous or intraperi- trimethoprim-sulfa preparations rates and biopsies are other useful toneal injection of 3 parts nonlactated diagnostic tools. Radiographs may be balanced electrolyte solution to 1 part Itraconazole Fungal infections obtained with standard equipment or, 5% dextrose. Optimizing ambient Furosemide Promote fluid excretion preferably, by using high-definition temperature and humidity will aid in x-ray equipment, such as dental or recovery.

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Table 2. Differential Diagnosis for Clinical Signs in Amphibians

SYSTEM CLINICAL SIGNS DIFFERENTIAL DIAGNOSIS DIAGNOSTICS

General Anorexia Inadequate husbandry (temperature, humidity, food History, review husbandry/diet, physical exam, offered, crowding), physiologic causes (behavioral or fecal exam, gastric lavage, hematology, environmentally induced), generalized infection (viral, radiography, ultrasonography, endoscopy, bacterial, fungal), chytridiomycosis, GI parasitism, GI laparoscopy, laparotomy impaction, ocular/CNS disease

Emaciation Husbandry, malnutrition, GI impaction, GI parasitism, History, review husbandry/diet, physical exam, pulmonary parasitism, chronic infection, failure, fecal exam, hematology, radiography, neoplasia ultrasonography, endoscopy, laparoscopy, laparotomy

Coelom Firm swelling Gastric or intestinal impaction, overeating, bacterial Palpation, transillumination, fecal exam, enlargement septicemia (“red leg”), coelomic mass (abscess, radiography, ultrasonography, gastric lavage, granuloma, neoplasia), organomegaly, retained ova, aspirate and cytology, biopsy, endoscopy, peritonitis, cystitis laparoscopy, laparotomy

Edema/ascites Renal disease, heart failure, heart failure, Palpation, transillumination, aspirate and bacterial septicemia (“red leg”), viral disease, cytology, fluid analysis (total protein), peritonitis, hepatic failure, hypoproteinemia, bacterial culture, hematology retained ova

Organomegaly Hepatitis, splenitis, bacterial septicemia, chlamydiosis, Palpation, transillumination, radiography, mycobacteriosis, fungal infection ultrasonography, aspirate and cytology, laparoscopy, laparotomy, bacterial/fungal culture, biopsy

Skin Discoloration Bacterial septicemia (“red leg”), thermal burns, Skin scraping, wet mount, cytology, excessive UV light exposure, chytridiomycosis or other bacterial/fungal culture, biopsy fungal infection, viral infection, chlamydiosis, gas bubble disease (aquatic )

Ulceration Trauma, bacterial dermatitis, bacterial septicemia, Skin scraping, wet mount, cytology, mycobacteriosis, chlamydiosis, fungal infection, bacterial/fungal culture, biopsy excessive UV light exposure, nematodiasis, gas bubble disease (aquatic species)

Rectal prolapse in a Colorado River toad (Bufo alvarius). Fungal dermatitis (chromomycosis) in an Eyelash leaf (Ceratobatrachus guentheri).

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SYSTEM CLINICAL SIGNS DIFFERENTIAL DIAGNOSIS DIAGNOSTICS Skin Masses Mycobacteriosis, fungal infection, protozoan cyst, Aspirate and cytology, bacterial/fungal cestodes, mites, mineral deposit, neoplasia culture, biopsy

Focal hyperplasia Chytridiomycosis or other fungal disease, Skin scraping, biopsy nematodiasis

Cottony growth Saprolegniasis (aquatic species) Skin scraping, wet mount, biopsy Gastrointestinal Prolapse of cloaca, Tenesmus, GI parasitism, GI foreign body, Aspirate, biopsy, fecal exam, radiography, rectum, bladder or gastroenteritis, peritonitis, retained ova, neoplasia ultrasonography, reduce prolapse and oviduct reevaluate

Gastric prolapse GI parasitism, toxins, terminal illness Fecal exam, reduce prolapse and reevaluate

Regurgitation GI parasitism, gastroenteritis, GI impaction, GI foreign Fecal exam, radiography, ultrasonography body, toxicosis

Diarrhea/mucoid GI parasitism, gastroenteritis, GI foreign body Fecal exam, bacterial culture stool

Lack of stool GI impaction, GI foreign body, GI parasitism Radiography, ultrasonography Musculoskeletal Masses Abscess, granuloma, mycobacteriosis, protozoan cyst, Radiography, aspirate and cytology, biopsy cestodiasis, metabolic bone disease, neoplasia

Skeletal abnormali- Fracture, trauma, metabolic bone disease (Ca/P Review husbandry/diet, radiography ties imbalance, vitamin D deficiency), spindly leg syn- drome, developmental malformation (secondary to malnutrition, toxicosis)

Ocular Ocular Trauma, bacterial conjunctivitis, bacterial keratitis, History, ophthalmic exam, cytology, bacterial abnormalities panophthalmitis, corneal ulcer, corneal lipidosis, culture, hematology, plasma cholesterol corneal edema, cataract

Central nervous CNS signs, head Trauma, thiamine deficiency, bacterial / chlamydial Empirical treatment system tilt, paresis/paralysis meningitis, toxicosis, septicemia, terminal illness

"Spindly leg syndrome" in a green-and-black poison dart frog Cutaneous granulomas caused by Mycobacterium chelonia in a Puerto (Dendrobates auratus). Rican crested toad (Peltophryne lemur).

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Bacterial dermatitis (Aeromonas sp.) in a Puerto Rican crested toad Massive fluid retention caused by chronic renal failure in a White's (Peltophryne lemur). tree frog (Litoria caerulea).

Lipid keratopathy in a White's tree frog (Litoria Bite wound in a Colorado River toad (Bufo Massive pericardial effusion in a Surinam toad caerulea). alvarius) inflicted by a Mexican beaded lizard (Pipa pipa) with idiopathic myocardial fibrosis. (Heloderma horridum).

Subcutaneous cestode (Spargana) in a Blood collection by cardiac puncture in a Bacterial septicemia (“Red leg”) in a Bell’s (Dyscophus antongilii). young Colorado River toad (Bufo alvarius). horned frog (Ceratophrys ornata).

For an in-depth review of diseases, diagnostics and therapeutics of amphibians, readers are referred to Wright KM, Whitaker BR (eds): Amphibian Medicine and Captive Husbandry. Malabar, FL, Krieger Publishing, 2001, www.krieger-publishing.com.

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