Fungi (singular is fungus) are a kind of germ. Most fungi are harmless to humans, but there are several that can cause harmful infections, especially in HIV+ people.

Candidiasis is a very common fungal infection usually caused by Candida albicans. This yeast-like fungus is found in all healthy people. The immune system and bacteria normally found in the body generally keep Candida under control.

When it gets out of control, Candida can cause problems in the mouth, throat, or vagina. This can happen when the immune system is weakened by HIV or when you take antibiotics (which can kill the helpful bacteria).

The medications used to fight Candida are anti-fungal drugs called “azoles.” Examples are Nizoral (ketoconazole), Diflucan (fluconazole), or Sporanox (itraconazole). Azoles should not be used in pregnant women. In addition, many of the anti-fungal drugs interact with HIV drugs.

Candidiasis can come back repeatedly. Some doctors prescribe anti-fungal drugs on a long-term basis, but this can lead to drug-resistant Candida that is more difficult to treat.

• Whitish coating of the tongue and/or the inside of the cheeks
• Usually occurs with CD4 cell count less than 300
• May affect appetite
• More likely to occur in diabetics and when steroid medications (prednisone or certain asthma inhalants) are being taken

Treatment:

• Local treatment with clotrimazole troches (lozenges) or nystatin liquid
• Systemic (body-wide) treatment using oral anti-fungal medications
• In most severe cases, amphotericin B is used, but it can have serious side effects
• Alternative treatment: Mouthwash derived from tea-tree oil (not the oil itself—this can be very irritating!)

• May occur with high CD4 cell counts (around 500), but more likely to develop at lower CD4 counts
• So common in HIV+ women that any woman who is undiagnosed but gets recurrent vaginal yeast infections should consider being screened for HIV
• Symptoms include itching, burning, and pain around the vagina, labia, or anal area and thick, curd-like vaginal discharge
• HIV+ women often have recurring yeast infections that are difficult to treat
• Antibiotics, steroids, birth control pills, and foods high in sugars or starches (breads, pastas, and alcohol) all promote the growth of Candida
• Douching reduces levels of helpful bacteria in the vagina and is not recommended for HIV+ women

Treatment:

• Local treatment with over-the-counter creams like Monistat or Gyne-Lotrimin or prescription anti-fungal creams (HIV+ women often need longer courses of treatment)
• For difficult-to-treat infections, use prescription oral anti-fungal drugs
• Alternative treatment: Acidophilus (in supplements or yogurt)

• Usually occurs at very low CD4 cell counts (less than 100)
• An AIDS-defining opportunistic infection
• Major symptom is painful swallowing (dysphagia)
• Often diagnosed via gastrointestinal endoscopy
• Possible in anyone who has thrush and a low CD4 cell count

Treatment:

• Systemic therapy with azoles, fluconazole is generally used

The fungus Cryptococcus neoformans is very common. It is found in soil and bird droppings. While most people have been exposed to this fungus, they generally have immune systems that are healthy enough to prevent Cryptococcus from causing disease.

In immune-compromised people, especially HIV+ people with less than 100 CD4 cells, Cryptococcus can cause a serious infection called meningitis in the lining of the spinal cord and brain. If it is not treated correctly, cryptococcal meningitis can cause coma or death.

Symptoms:

• Fever
• Headache
• Vision problems
• Confusion
• Nausea
• Vomiting

Let your doctor know if you experience any of these symptoms. (Bacterial, not cryptococcal, meningitis causes a stiff neck.)

Diagnosis:

• Lumbar puncture (spinal tap) to gather a specimen of the cerebrospinal fluid (CSF), the fluid that surrounds the brain and spine
• Blood tests will usually show a high level of serum cryptococcal antigen

Treatment:

• In most cases, a two-week regimen of intravenous amphotericin B and 5-flucytosine is used
• Afterwards, fluconazole is used for maintenance
• In milder cases of meningitis, oral fluconazole is sometimes used from the beginning

Histoplasmosis is caused by infection with the Histoplasma capsulatum fungus, which is common in the soil of the Midwest river valleys, the Caribbean, and Central and South America.

In a healthy person, the infection is usually confined to the lungs, causing only mild symptoms. In HIV+ people with low CD4 cell counts (below 200), the infection can be life threatening. However, histoplasmosis is not a common disease in HIV+ people.

Symptoms:

• Fever
• Fatigue
• Shortness of breath
• Cough
• Weight loss

Diagnosis:

• Confirmation of the organism in sample of blood, sputum, or other tissue

Treatment:

• Initial intravenous amphotericin B, then change to maintenance therapy with oral itraconazole (sometimes fluconazole)

Aspergillosis is caused by Aspergillus, a very common group of fungi. In people with healthy immune systems, it usually causes mild or moderate lung problems. In people with suppressed immune systems, it can be life threatening. Aspergillosis was more common in the earlier days of AIDS. It is rarely seen in HIV+ people today

Symptoms:

• Pain in the sinuses, nose, or ear canal
• Facial swelling
• Pneumonia-type symptoms such as cough, difficulty breathing, and fever

Diagnosis:

• Material (sputum, nasal secretions) is stained and cultured for the organism

Treatment:

• Traditional: Intravenous amphotericin B
• New (and possibly improved): Oral antifungal voriconazole

Fungal infections can be very common, and in some cases, very serious for HIV+ people. However, on-going medical care allows for the effective prevention or early diagnosis and treatment of these infections. In addition, most of the more serious fungal infections are more likely to occur in HIV+ people with low CD4 cells (especially less than 100). One way to prevent fungal infections from occurring is to keep the immune system healthy by using HIV drugs when necessary and seeing your doctor on a regular basis. 

1		Bartlett, J.G. (2003). Management of opportunistic infections and other complications of HIV infection. Medical Management of HIV Infection, Online Edition. Ch. 5: Retrieved July 2003 from http://hopkins-aids.edu/publications/book/book_toc.html
2		Herbrecht R. et. al. (2002). Voriconazole versus amphotericin B for primary therapy of invasive aspergillosis. New England Journal of Medicine, 347. 408-415.
3		Powderly, W.G. (2001). Manual of HIV Therapeutics, Second Edition. Philadelphia: Lippincott, Williams & Wilkins.