Hair follicles, the tiny pores in skin from which hairs emerge and grow, can get infected – the condition is called Folliculitis. We diagnose it by observing that a patient’s “rash” really involves mainly the follicles. The follicles turn red, and may even have pus. Often the spaces of skin in-between are unaffected, but if extensive, they too may be red. Folliculitis often itches, though not always. See the pictures below.
The most common germs are bacteria, which can be treated with antibiotics. Almost everyone gets a mild folliculitis from time to time, which goes away on its own; consequently, all we recommend in such cases are hygiene (soap & water), or maybe putting warm / hot compresses on the area, at least 3-4 times a day, every hour if they feel like it and have nothing else to do. We tell patients to test the heat on their forearm first, so as not to burn themselves.
The most common bacteria is Staphylococcus aureus (“Staph”), so when we make the diagnosis, we use whatever medications work for it, depending on what drug resistance exists locally. Oral antibiotics work best, but we only prescribe them if the folliculitis is extensive or actively spreading. For people who are taking long courses of antibiotics for other reasons, we may suspect the bacteria E. coli; if the folliculitis began soon after using hot tubs or heated swimming pools, Pseudomonas may be responsible, Severely immunocompromised persons might have any bacteria or other germ.
Sometimes the condition is caused by fungi. We’d consider this, and use anti-fungal medications, if regular treatment didn’t work. One common place for fungal folliculitis is the beard, or in moist areas like on the back of a bedridden person. As noted above, severely immunocompromised persons also get this.
Some examples of Folliculitis: