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

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       Most present with non‐specific signs such as anorexia, dehydration, and lethargy.

       Upper respiratory signs include bilateral nasal–ocular discharge, blepharedema, conjunctivitis, “pus” in conjunctival sacs (actually desquamated debris), swelling and closure of palpebral fissures due to squamous metaplasia and glandular hypertrophy, and secondary bacterial infections.

       Ulcerative stomatitis, glossal plaques, and glossitis may also be observed.

       Chelonian aural abscesses do not appear to be directly associated with hypovitaminosis A based on current findings, but squamous

       metaplasia may lead to secondary aural infections.

       Bacterial infection

       Hepatic/renal disease

       UVB/thermal burns

       Ocular trauma

       Water‐based toxins

       Poor overall husbandry/diet

       Improper conspecific arrangement

       Metabolic bone disease

       Presumptive diagnosis is based upon history, clinical presentation, and response to correct supplementation.

       Liver biopsy for histopathology and testing vitamin A levels can be performed, but there is a lack of normal values.

       Hepatic vitamin A levels are normally extremely high in carnivores, much lower in herbivores, and intermediate in insectivores and omnivores.

       Sex of animal, testing methodology, and reported units can affect results.

       Squamous metaplasia

       Epidermal ulceration

       Omnivores and carnivores can be fed whole prey still containing liver, or for semiaquatic turtles, can offer extruded diet with correct form of vitamin A.

       Supportive feeding, including esophageal feeding tubes may be needed until the reptile feels better and can actually see the food.

       For herbivores, feed plenty of leafy greens and red/orange/yellow vegetables.

       Treatment for insectivores is more complex.

       Invertebrates store retinols in the retina only, so invertebrates (or juvenile forms) without eyes have no vitamin A.

       Dusting invertebrates must be done immediately before feeding, as the vitamin powder is usually often self‐groomed off the invertebrate before the reptile has ingested it.

       Gut‐loading guidelines are still controversial but seem to still be the best option—especially consider the Li diet (see Suggested Reading).

       Consider feeding non‐toxic, wild‐caught invertebrates, as they generally have much higher levels of vitamin A than captive‐raised invertebrates.

       Proper education about correct diet for the species.

       Discuss correct formulation of vitamin A for the species.

       Correct invertebrates to offer and how to supplement them.

       Clear explanation of differences between water‐soluble and fat‐soluble vitamins.

       Parenteral treatment or oral supplementation of retinol forms to herbivores should be avoided.

       Use dietary carotenoids (non‐beta carotene) instead.

       For omnivorous, carnivorous, and insectivorous reptiles, parenteral vitamin A (usually has vitamin D3 as well): 500–5,000 iu/kg IM q7–14d for up to 4 treatments.

       Dosing must be done carefully to avoid over supplementation with vitamin A in the retinol form.

       Other treatment focuses on managing with systemic antibiotics/antifungals for secondary infections.

       Judicious topical use of silver sulfadiazine cream for epidermal ulcers can help.

       Removal of conjunctiva plugs or flushing nasolacrimal ducts (when present) can be beneficial symptomatic treatment.

       Re‐evaluate for improvement of clinical signs.

       Review owner’s diet plan

       Repeat liver biopsy if feasible