Introduction
Histoplasmosis is a disease that can occur in cats when they ingest or inhale the fungus Histoplasma capsulatum. This type of fungus exists in nature in many areas, and cats that are exposed to the fungus do not always develop the histoplasmosis disease. However in some cases the fungus becomes lodged in the body and the resulting disease develops.
Histoplasmosis can be a very difficult disease to diagnose, and the condition can be deadly. The good news is that once the disease has been identified it can be successfully, and permanently, treated.
Treating Histoplasmosis
In cases where the fungus has spread throughout the body, also known as disseminated histoplasmosis, the standard treatment is the antifungal medication itraconazole. The medication is given orally twice a day, often for many months. In mild cases of histoplasmosis, the anti-fungal medication ketoconazole is normally prescribed. This medication is given orally twice a day for 4-6 months.
Itraconazole can cause side effects such as vomiting, diarrhea, lethargy, and abdominal pain. Ketoconazole can cause stomach upset and so it is generally given with food. Itraconazole is an extremely expensive medication, and so this medication is generally only prescribed in cases where it is absolutely necessary.
In severe cases of histoplasmosis when the disease has progressed to a point where the cat’s life is in danger, the anti-fungal medication amphotericin B or amphotericin B lipid complex is administered intravenously. Amphotericin B can cause damage to the kidneys, and in many instances doctors expect some kidney damage to occur if this medication is used. However in some cases it may be the only cat’s chance for survival. If the medication is administered properly, and the cat’s kidneys are flushed and monitored, than damage to the kidneys can be reduced or avoided.