The mucous membranes that line the nose and pharynx, and the white blood cells in the lungs, should normally trap any fungal spores. Antibodies also respond to fungal infections. But there are times when fungi can overcome the immune response of the body and cause a lung infection. Fortunately, there are medications available for such times.
Prednisone
Prednisone is a synthetic corticosteroid, or a manufactured steroid hormone. The human body naturally makes corticosteroids in the adrenal cortex, the outer section of the adrenal gland. Prednisone works in the same way as the natural corticosteroids. As part of the response to infection, the body starts what is called an inflammatory response and releases white blood cells to the infected area. Sometimes, the response is too great or lasts for too long. Prednisone fights inflammation by lowering the number of white blood cells that go to the affected area and the production of proteins involved in the inflammatory response. It is one treatment for allergic bronchopulmonary aspergillosis, according to Samuel Shelburne, M.D., Assistant Professor in the Department of Internal Medicine at Baylor College of Medicine in "Current Medical Diagnosis & Treatment." This is a lung infection caused by the Aspergillus fungus.
Azoles
The azole antifungal medications include itraconazole, voriconazole and fluconazole, among others. These three are the main azole medications used to treat fungal diseases of the lungs. The particular medication used depends upon the type of fungus infecting the lungs. An azole medication can be used to treat allergic bronchopulmonary aspergillosis, as well as the lung infections caused by the Coccidioides, Histoplasma, Cryptococcus and Blastomyces fungi, as written in "The Merck Manual for Healthcare Professionals" by Alan Sugar, M.D., Medical Director of the Infectious Disease Clinical Services and HIV/AIDS Program at Cape Cod Healthcare. All of the azoles interfere with an enzyme the fungi use to make ergosterol. Enzymes are proteins that speed up a process. Ergosterol is a substance in the fungi cell membrane, and without enough ergosterol, they die.
Amphotericin B
Like the azoles, the antifungal medication called amphotericin B is a treatment for allergic bronchopulmonary aspergillosis, the coccidioidomycosis, histoplasmosis, cryptococcosis and blastomycosis lung diseases. Amphotericin B attaches to the ergosterol in the cell membrane of the fungus and changes the permeability of the fungal cell. In other words, it changes what the fungus normally allows to enter and exit its cell. This also results in pores being created throughout the cell membrane. Too much water can now enter the fungal cell. In addition, substances that the fungus needs to keep within its cell, so it can carry out its daily activities, now leak out of the cell. The combined action kills the fungus.
References
- "Current Medical Diagnosis & Treatment 2010"; Stephen McPhee, M.D., Maxine Papadakis, M.D.; 2010
- The Merck Manual for Healthcare Professionals: Blastomycosis
- The Merck Manual for Healthcare Professionals: Coccidioidomycosis
- The Merck Manual for Healthcare Professionals: Cryptococcosis
- The Merck Manual for Healthcare Professionals: Histoplasmosis
