Candida (Thrush)

Candida is a common fungus (yeast) that is normally controlled by the immune system but can grow in mucous membranes or elsewhere in your body causing symptoms known as candidiasis (thrush).

Both HIV-negative and positive people may experience candidiasis.

Among people with HIV, mild candidiasis in the mouth is relatively common even when their CD4 cell count is well between 200 and 400. On the gums, tongue, inner cheek and/or upper throat (oropharyngeal candidiasis), Candida grows in white clumps that can be scraped away, or causes red patches called erythema. Oesophageal candidiasis (in the gullet) is more serious and counts as an AIDS-defining illness. These forms of candidiasis can make it painful to eat.

Genital candidiasis may occur in the vagina in women, under the foreskin in men, causing itching or slight pain. In people with advanced HIV infection, Candida may grow in other parts of the body, such as the lungs (pulmonary candidiasis).

It is easy to diagnose candidiasis in the mouth or oesophagus by inspecting the lesions. Doctors may take a tissue sample or smear to test for the fungus when other parts of the body are affected.

Treatment
Candidiasis responds well to anti-fungal drugs. There are several tablet-form drugs available such as ketoconazole (Nizoral), itraconazole (Sporanox) and fluconazole (Diflucan). Some are available in other forms, such as liquid solution for oral candidiasis, creams for skin or nail infections and pessaries for vaginal candidiasis. You may also be offered anti-fungal lozenges such as clotrimazole, nystatin (Nystan) or amphotericin. Some of these preparations are available ‘over the counter’ at your local pharmacy.

Anti-fungal tablets can cause side effects such as nausea, vomiting and rashes. Itraconazole and ketoconazole also interact with a number of other drugs used by people with HIV, so make sure your doctor or pharmacist explains about any potential interactions.

Some Candida strains become resistant to fluconazole, especially among people with low CD4 counts or who have taken it for long periods.

Prevention
Anti-fungal drugs may be effective at preventing candidiasis among people with low CD4 counts. However, doctors differ in their recommendations. Some do not favour using anti-fungal drugs as preventative therapy (prophylaxis), as they believe that it is easy to treat any attacks of candidiasis that do occur, and that prolonged exposure to the drugs is likely to encourage resistance.

Other doctors believe that anti-fungal prophylaxis is not more likely to cause resistance than treating intermittent episodes. They point out that prophylaxis may also help to prevent more serious fungal infections such as cryptococcal meningitis, although this is relatively rare in Britain.

Some complementary therapists may recommend avoiding sweet food, white flour and starchy foods. However, this is unproven so you should consult your dietician or doctor to ensure that you are getting enough calories in your diet, if you consider this option.