Mycobacterium Avium Complex (MAC) - Opportunistic Infections
Mycobacterium avium complex, or MAC as it’s more commonly known, is an extremely serious opportunistic infection for someone who is HIV positive.
It’s caused by very common bacteria which in a person with a healthy immune system would cause no real problems. They would be able to fight it off before any symptoms occurred. However in someone whose immune system is shot to pieces thanks to HIV these tiny bacteria, which are related to tuberculosis, can prove deadly.
For something that can do so much damage to someone with HIV, it’s an incredibly common bacterium. It can be found in water, food, soil and dust. It gets into the body through the mouth - either transferred from the hands or by breathing in infected soil or dust.
MAC is usually only found in people whose CD4+ count goes below 50 and up to 50% of people with full blown AIDS develop it.
The symptoms are extremely unpleasant. A very high fever is common accompanied by chills, stomach ache, severe tiredness and worst of all constant diarrhea. Anaemia is common and because of the diarrhea, weight loss and dehydration are guaranteed.
The infection can be localized, attacking just one part of the body. But if treatment is left too late it can spread throughout the whole body.
It usually infects the intestines, lungs, liver, spleen and bone marrow first. When the bacteria spreads it can be responsible for hepatitis, pneumonia and several blood infections.
It’s important to remember though that there are quite a few opportunistic infections that can cause these symptoms and this can sometimes make Mycobacterium avium complex difficult to diagnose.
Diagnosis is usually based on taking samples blood, saliva or urine to see whether the bacteria are present. It may then take several weeks to culture any bacteria and identify the problem. In the meantime doctors may decide to treat the infection as MAC, as a precautionary measure, using a combination of antibiotics. Both azithromycin and clarithromycin have both been found to be very successful in clearing up the infection.
But once the infection has been tackled it’s essential that preventative treatment continues otherwise the illness will return and thanks to an increasingly tired immune system it will probably get worse each time.
Continuing with azithromycin and clarithromycin has proved effective in preventing a reoccurrence of the infection. Rifabutin has been shown to reduce the rate at which people develop MAC by as much as 50%. However rifabutin does have some serious side effects such as rashes, fever, kidney and liver damage and stomach pains.
Because MAC is a common bacterium it can be very difficult to avoid it. As with other opportunistic infections, the best way to keep this one at bay is to take strong anti HIV medication to keep your CD4+ count above 100.