Long-term outcome of therapy for 59 cats and 11 dogs with cryptococcosis.
OBJECTIVE
To determine the outcome of therapy in cats and dogs with naturally occurring cryptococcosis. Design Retrospective study of 59 cats and 11 dogs at the University Veterinary Centre Sydney from 1986 to 2004.


METHODS
Following detailed analysis of case notes potential associations between patient characteristics, cryptococcal species, retroviral status (cats), disease severity and type of therapy were examined in relation to duration and success of therapy. Treatment protocols based on amphotericin B, fluconazole and itraconazole were compared.


RESULTS
Seventy-six percent of feline patients were successfully treated. For cats, the presence of central nervous system disease was the only factor found to influence outcome. Cats with neurological involvement, disseminated disease or refractory disease treated with amphotericin B containing protocols did as well, on average, as cats with less severe disease treated with azole monotherapy. Amphotericin B was thus an effective agent for treating severe cases of cryptococcosis. The median cumulative dose of amphotericin B for cats cured at the first attempt was 16 mg/kg (range 7 to 23 mg/kg). The median duration of treatment required to effect a cure at first attempt was significantly shorter for fluconazole (4 months; range 1 to 8 months) than for itraconazole (9 months; range 3 to 24 months; P = 0. 0191; Mann Whitney U test). The success rate for treatment of canine cases was 55%. No factor appeared to influence disease outcome in dogs. Large cumulative doses of amphotericin B could be administered via the subcutaneous route in both species and generally with minimal nephrotoxicity. Recrudescence occurred in a significant proportion of animals, in some cases despite a reduction of serum latex cryptococcal antigen agglutination test to zero.


CONCLUSIONS
Although the prognosis of cryptococcosis should be described as guarded, a majority of the canine and especially feline patients can be expected to be cured, although treatment is protracted and expensive.
O'Brien
C R
CR
Faculty of Veterinary Science, University of Sydney NSW 2006. cobrien@unimelb.edu.au
Krockenberger
M B
MB
Martin
P
P
Wigney
D I
DI
Malik
R
R
D000666:Amphotericin B / Q000009:adverse effects / Q000627:therapeutic use; D000818:Animals; D000981:Antiprotozoal Agents / Q000009:adverse effects / Q000627:therapeutic use*; D002371:Cat Diseases / Q000188:drug therapy*; D002415:Cats; D003457:Cryptosporidiosis / Q000188:drug therapy / Q000662:veterinary*; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D004305:Dose-Response Relationship, Drug; D005260:Female; D015725:Fluconazole / Q000009:adverse effects / Q000627:therapeutic use; D017964:Itraconazole / Q000009:adverse effects / Q000627:therapeutic use; D008297:Male; D011379:Prognosis; D012189:Retrospective Studies; D012720:Severity of Illness Index; D013997:Time Factors; D016896:Treatment Outcome
D000981:Antiprotozoal Agents; D017964:Itraconazole; D000666:Amphotericin B; D015725:Fluconazole