Pseudofolliculitis barbae

Pseudofolliculitis barbae (PFB), is a medical term for persistent irritation caused by shaving. Pseudofolliculitis barbae was first described in 1956. Pseudofolliculitis barbae (PFB), is a medical term for persistent irritation caused by shaving. Pseudofolliculitis barbae was first described in 1956. Razor burn is a less serious condition caused by shaving, characterized by mild to moderate redness and irritation on the surface of the skin. Unlike PFB, it is usually transient and there is no infection involved. There is also a condition called folliculitis barbae. The difference between the two is the cause of the inflammation in the hair follicles. Folliculitis barbae is caused by viral or bacterial infections, where pseudofolliculitis is caused by irritation from shaving and ingrown hairs. A related condition, pseudofolliculitis nuchae, occurs on the back of the neck, often along the posterior hairline, when curved hairs are cut short and allowed to grow back into the skin. Left untreated, this can develop into acne keloidalis nuchae, a condition where hard, dark keloid-like bumps form on the neck. Both occur frequently in black men in the military, where it is so common that services often have widely known protocols for management Pseudofolliculitis barbae (PFB) is most common on the face, but it can also happen on other parts of the body where hair is shaved or plucked, especially areas where hair is curly and the skin is sensitive, such as genital shaving (more properly termed pseudofolliculitis pubis or PFP). After a hair has been shaved, it begins to grow back. Curly hair tends to curl into the skin instead of straight out the follicle, leading to an inflammation reaction. PFB can make the skin look itchy and red, and in some cases, it can even look like pimples. These inflamed papules or pustules can form especially if the area becomes infected. This is especially problematic for some men who have naturally coarse or tightly curling thick hair. Curly hair increases the likelihood of PFB by a factor of 50. If left untreated over time, this can cause keloid scarring in the beard area. Pseudofolliculitis barbae can further be divided into two types of ingrown hairs: transfollicular and extrafollicular. The extrafollicular hair is a hair that has exited the follicle and reentered the skin. The transfollicular hair never exits the follicle, but because of its naturally curly nature curls back into the follicle causing fluid build-up and irritation. A common polymorphism in a keratin gene (K6hf) has been linked to PFB, suggesting that it may be a genetic risk factor. This sequence change leads to an amino acid substitution in the highly conserved helix initiation motif of the K6hf rod domain. Carriers of the A12T polymorphism are six times more likely to develop PFB compared with people homozygous for the wild-type K6hf sequence. This suggests K6hf mutation structurally weakens the companion layer separating the inner and outer root sheath and increases the chances that a beard hair will in-grow.