CLINICAL PICTURE: A 55-year-old man presented with intermittent low back pain which was progressively worsening, fever, anorexia, low back pain and a 10-kg weight loss. He had underlying diabetes mellitus and ischaemic heart disease. He gave a history of travel to caves for worship. Clinically, the most significant findings included nodular lesions in the anterior fauces and left palatoglossal region. Computed tomographic scan revealed bilateral adrenal masses. Biopsies were taken from the palatal nodules, which revealed histiocytes with numerous histoplasma organisms.
TREATMENT: He was commenced on itraconazole 200 mg daily for a period of 9 months. There was a dramatic initial response with settling of his fever and this was followed by subjective improvement in his well-being.
OUTCOME: He is presently on follow-up and has completed 9 months of itraconazole therapy with resolution of all his symptoms and has gained about 10 kg of weight.
OBJECTIVES: To evaluate thermotolerance and antifungal susceptibility of feline Malaysian Sporothrix isolates, compare microdilution (MD) and E-test results, and investigate changes in susceptibility during azole therapy.
METHODS: Sporothrix schenckii sensu stricto was isolated from 44 cats. Thermotolerance was determined via culture at 37°C for 7 days. Susceptibility to itraconazole (ITZ), ketoconazole (KTZ) and terbinafine (TRB) was assessed in 40 isolates by MD; to amphotericin B (AMB), KTZ, ITZ, fluconazole (FLC) and posaconazole (POS) by E-test. Results were statistically compared by Pearson's Product Moment. In eight ketoconazole treated cats, susceptibility testing to itraconazole and ketoconazole was repeated every two months for six months.
RESULTS: Thermotolerance was observed in 36 of 44 (82%) isolates. Assuming that isolates growing at antifungal concentrations ≥4 mg/mL were resistant, all were resistant on E-test to FLC and AMB, 11 (28%) to POS, 6 (15%) to ITZ and 1 (3%) to KTZ. On MD, 27 of 40 (68%) were resistant to TRB, 2 (5%) to ITZ and 3 (8%) to KTZ. There was no correlation between E-test and MD results (KTZ r = 0.10, P = 0.54, and ITZ r = 0.11, P = 0.48). MD values for ITZ and KTZ did not exceed 4 mg/L during KTZ therapy.
CONCLUSION: The majority of feline isolates in Malaysia are thermosensitive. Lack of correlation between E-test and MD suggests that the E-test is unreliable to test antifungal susceptibility for Sporothrix spp. compared to MD. KTZ was the antifungal drug with the lowest MIC. Prolonged KTZ administration may not induce changes in antifungal susceptibility.