Histoplasmose pulmonar grave em um gato doméstico: tratamento com Anfotericina B e Itraconazol / acute pulmonary histoplasmosis in a domestic cat treated with Amphotericin B and Itraconazole

ABSTRACT

Background: Histoplasmosis is a systemic mycosis whose etiologic agent is the fungus Histoplasma capsulatum. This fungal infection, which is the second most frequent systemic mycotic fungal disease in felines in the United States, has rarely been found in cats in Brazil. This paper reports on a case of acute pulmonary histoplasmosis in a domestic cat treated with oral itraconazole associated with amphotericin B administered subcutaneously. This treatment resulted in clinical remission of the patient’s symptoms, as evidenced by radiographic follow-ups.Case A domestic cat suffering from acute dyspnea was taken to a veterinary clinic. The animal was subjected to emergency oxygen therapy, and kept at rest through sedation with midazolam. A physical examination revealed normally colored mucosa, 8% dehydration, bristly fur, body condition score 2/9, tachypnea with respiratory rate of 100 breaths per minute and expiratory dyspnea. The radiographic examination showed marked opacification of all the pulmonary fields, with a mixed pattern (interstitial and alveolar) of heterogeneous appearance and diffuse distribution, which are changes consistent with an inflammatory infectious process (pneumonia). A cytological analysis of the pleural fluid revealed round to oval-shaped intracytoplasmic structures, varying in size from 2 to 4 μm, inside foamy macrophages, consistent with Histoplasma capsulatum. Based on the diagnosis of pulmonary histoplasmosis, and in view of the patient’s acute respiratory distress, it was decided to treat the cat using itraconazole associated with amphotericin B. Itraconazole was administered orally at a dose of 100 mg/cat every 24 h, while amphotericin B was administered subcutaneously at a dose of 0.5 mg/kg, combined with 100 mL of sodium chloride 0.9% and 100 mL of 5% glycated serum, with monitoring of serum concentrations of symmetric dimethylarginine (SDMA).[...]