Abstract

To date we have identified 143 cases of fungal infections, comprising 19 species of fungi, in 24 species of marine mammals. Of these cases, 48% percent stranded with disease or developed an illness during rehabilitation, while 52% were residents of various zoological facilities. Of the latter, 42% had some type of preexisting disease, 52% were apparently healthy, and 6% were healthy neonates. Many of these fungal infections share clinical, hematologic, and biochemical aspects of bacterial infections. Clinical presentations are frustratingly nonspecific, ranging from chronic to fulminating, while laboratory findings demonstrate acute or chronic inflammation, just as with bacterial disease. With the exception of cryptococcal latex agglutination, the ELISA antigen method for histoplasmosis, and the diagnostically and prognostically useful serological tests for coccidioidomycosis, use of serology for diagnosis for mycoses is generally dismal. It is for this reason that biopsy and culture are the only definitive diagnostic methods.

In the recent years, a number of new antimycotic drugs have been introduced. These include itraconazole and fluconazole that appear to be somewhat effective against Aspergillus, Candida, and the endemic fungi, and the lipid formulations of the microencapsulated amphotericin B products that have limited efficacy against zygomycosis in humans and marine mammals. For all fungal infections, the time honored method is to treat longer than the time necessary to eliminate the organism. It is therefore important to rely on clinical signs, cultures, and follow-up diagnostic tests, such as blood work, endoscopy, and serology to help make the most informed decision on discontinuing therapy.

Unfortunately, diagnostic modalities have greatly lagged behind therapeutics, however with improvements in serodiagnostic tests for metabolic byproducts and cell wall constituents, as well as emerging methods involving molecular biological techniques, our ability to make timely antemortem diagnoses should greatly improve.