VPT 421: Veterinary Toxicology (2+0)

DIAGNOSIS AND TREATMENT

Diagnosis

• Clinical signs are easily recognized in cases of marked photosensitivity but are similar to the primary actinic effects of sunburn in early or mild cases.
• Reference to the specific diseases in which photosensitization is an objective sign may assist in diagnosis of the underlying disease.
• Evaluation of serum liver enzymes and liver biopsies may be necessary to confirm the presence of hepatic disease.
• Examination of blood, feces, and urine for porphyrins can also be performed.

Treatment

• Treatment involves mostly palliative measures. While photosensitivity continues, animals should be shaded fully or, preferably, housed and allowed to graze only during darkness.
• The severe stress of photosensitization and extensive skin necrosis can be highly debilitating and increase mortality.
• Corticosteroids, given parenterally in the early stages, may be helpful. Secondary skin infections and suppurations should be treated with basic wound management techniques, and fly strike prevented.
• The skin lesions heal remarkably well, even after extensive necrosis.
• The prognosis and eventual productivity of an animal is related to the site and severity of the primary lesion and/or hepatic disease, and to the degree of resolution.