Trichomycosis axillaris is a harmless overgrowth of bacteria on the hairs of the underarm. The condition produces hard nodules that stick to the hair, which are cosmetically unattractive. Antibacterial soap or shaving the hair can resolve the issue.
Corynebacterium bacteria generally cause the condition. Most of the time, Corynebacterium tenuis is the specific species involved. The bacteria grow together in a clump on the hair shaft. Trichomycosis axillaris is not dangerous in itself and is not a symptom of any serious condition.
Both men and women can have the condition. Women of many countries tend to shave under the arms, so it may be more prevalent in men in those areas for that reason. The condition can appear at any age from puberty onward. Found all over the world, trichomycosis axillaris is in countries with hot or cold climates.
Sometimes, trichomycosis axillaris simply causes the armpits to smell unpleasant, and the clumps of bacteria are not obvious. With a thorough inspection, the sufferer can see the clumps of bacterial growth on the hairs of the armpit. These can be yellow, black, or red and encircle the hair. The clump colors can also affect the color of the person's sweat and may stain the underarms of clothing.
The hair can look as if beads are present on it, or it may look thicker than normal. The clumps are most commonly yellow colored in temperate countries, although people in tropical countries may also have red or black clumps. Usually, the bacteria stay on the outside of the hair shaft, but in some rare cases, they get into the hair and destroy it.
Although the condition is harmless, the clumps can be unsightly. The simplest way to resolve the problem is to shave or cut the hairs of the armpit, thus removing the clumps of bacteria. Another way of keeping the issue under control is to use antiperspirants regularly to keep sweat production down.
Medication may also be useful to kill the bacteria. Erythromycin and clindamycin creams can help. Cleansing agents with benzoyl peroxide are another potentially useful preparation. If the sufferer can keep the underarms dry and clean, he or she can prevent the bacteria from growing out of control again.
A similar condition can also affect the hairs of the genital tract. In this case, it is called trichomycosis pubis. The genital and armpit regions are the regions generally affected because these areas are more moist than other parts of the body.