Pseudofolliculitis barbae: Review and update on new treatment modalities

Military Medicine, Jul 2003 by Garcia-Zuazaga, Jorge

Pseudofolliculits barbae, PFB, is a common cutaneous disease encountered frequently in medical practice. PFB represents a chronic inflammatory condition of the hair follicle caused by ingrown hairs producing an inflammatory foreign body reaction. The pathogenesis of PFB is multifactorial. Factors such as hair type and direction of hair growth play a role in the initial inflammatory reaction. In the armed forces, PFB represents a real challenge for both the physician and the patient. The combat environment, with the recent threat of biological and chemical weapons, requires the servicemen to be cleanshaven for appropriate gas mask fitting around the face. This article will review the etiology, pathogenesis, classification, and newer treatment modalities in the management of PFB.

Introduction

Pseudofolliculitis barbae (PFB) is a common cutaneous infection affecting individuals with tightly coiled hair. It is a chronic inflammatory condition of the hair follicle caused by ingrown hairs producing an inflammatory foreign body reaction. Strauss and Kligman first described this disorder in 1956. ' They made observation of a typical skin condition commonly seen in African American men and exacerbated by shaving. Other terms that have been used to describe pseudofolliculitis barbae include pilli incarnati, chronic sycosis barbae, and folliculitis barbae traumatica.

As the name implies, PFB is not a true folliculitis; the basis for its etiology is a foreign body inflammatory reaction produced by curved hairs reentering the skin and eliciting an inflammatory response.2 Improper shaving techniques are usually the precipitating stimulus of PFB. If severe, this condition may result in permanent scarring and occasionally keloid formation.

PFB in the Military

In the Armed Forces, treatment and prevention of PFB represents a real challenge for the physician. The combat environment, with the recent threat of biological and chemical weapons, requires the servicemen to be clean shaven for appropriate gas mask fitting around the face.3 Furthermore, with the military's strict uniform and grooming standards requiring clean-shaved personnel, some individuals with PFB have a significant dilemma when it comes to retention and advancement of their military careers.

Interestingly, the treatment and disposition of those service members with uncontrolled PFB varies among each branch of the Armed Forces. For example, the Department of the Navy allows for a permanent "no-shave" status for those individuals with severe PFB by recommendation of their commanding officers. However, these patients need to maintain their beard neatly groomed and clip the hair to maximum of Vis-inch long.

The United States Marine Corps has a different approach to disposition of patients with severe PFB. A member that has failed the PFB treatment protocol will be recommended for administrative separation at the convenience of the government.

Epidemiology

PFB is prevalent in any ethnic group predisposed to tightly coiled hair.2,4 The exact prevalence of PFB is unknown. Some studies cite that approximately 45 to 83% of the African American male population may suffer from the condition.2,4 PFB is also seen in Hispanic and Caucasian individuals, but on a much lesser scale.

Pathogenesis

The pathogenesis of PFB is multifactorial. The culprit is the curved hair follicle and, consequently, the curved hair shaft, which grows back into the skin surface or pierces the follicular wall when the hair is cut very short.4 Factors such as gross hair type, the orientation of the hair follicle, and the direction of hair growth all play a role in the initial inflammatory process.

Hair types

There are four gross hair types: wavy, helical, straight, and spiral.5 Most of the African American population has helical or spiral-shaped hair. In 1973, Steggerda and Seigert6 concluded that as the hair grows within the follicle, coils grown from spiralshaped hairs diminish in diameter as they grow outward toward the epidermis. This fact may explain the higher prevalence of PFB among African American men and women.

Hair Follicle

The hair follicular network plays a big role in the development of PFB. Microscopic studies of hair follicles suggest that each follicle has a different orientation toward the epidermis. "Hair follicles of blacks are curved and sit at on oblique angle, with the concavity toward the epidermis."4 During the process of shaving, the hair develops a needle-like tip, which may curve down and reenter the skin.

There are two follicular mechanisms involved in the pathogenesis of PFB, both inciting a foreign body inflammatory reaction: extrafollicular and transfollicular penetration.2-5

Extrafollicular penetration occurs when the hair shaft reenters the epidermis after curving downward and exiting the hair follicle.

Transfollicular penetration is the end result of improper shaving techniques such as stretching the skin taut during shaving, hair plucking, or tweezing. Applying skin tension during shaving causes the pointed hair tip to retract under the skin as tension is released. These hair tips then pierce the follicular wall entering the dermis, leading to a marked foreign body inflammatory response. Shaving techniques that allow for retraction of the hair back into the follicle (i.e., shaving against the grain and the use of a double-edge razor) could eventually lead to transfollicular penetration in PFB-susceptible individuals.7