A 32-year-old man comes to the office due to a rash on his neck. The rash has been present for 6 months and is associated with mild pain and tenderness. The patient has tried a number of emollients, cleansers, and astringent products without relief. Medical history is unremarkable. He does not use tobacco, alcohol, or illicit drugs. Examination findings are shown in the image below: Which of the following is the most likely diagnosis?

Question

A 32-year-old man comes to the office due to a rash on his neck.  The rash has been present for 6 months and is associated with mild pain and tenderness.  The patient has tried a number of emollients, cleansers, and astringent products without relief.  Medical history is unremarkable.  He does not use tobacco, alcohol, or illicit drugs.  Examination findings are shown in the image below:  Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

This patient has small, painful papules in the beard area consistent with pseudofolliculitis barbae (PB). PB is caused by penetration of the hair shaft into interfollicular skin, either through the lateral wall of the follicle (transfollicular penetration) or by curving back down into the skin after exiting the follicle (extrafollicular penetration). PB occurs in all ethnic groups but is most prevalent in black men due to tightly curled facial hair. Shaving with multiblade razors, which cut hair below the skin surface and leave an angled tip to the hair shaft, further increases the risk. The diagnosis of PB is usually apparent on clinical presentation. Complications include hyperpigmentation, secondary bacterial infection, and, occasionally, keloid formation. Discontinuation of shaving is first-line treatment and results in improvement in a few weeks. Subsequently, adjustment of shaving routine (eg, single blade, warm compresses prior to shaving) or use of alternative shaving methods (eg, hair clippers to leave hair longer) can be adopted. Chemical depilatories, laser hair removal, and topical eflornithine (which slows hair growth) can also be used. (Choice A) Inflammatory acne can present with small, tender papules on the neck. However, it usually also involves the face and most commonly presents in the adolescent years. (Choice B) As noted, PB can be complicated by secondary bacterial infection. However, bacterial folliculitis presents acutely with localized erythema and pustule formation. (Choice C) Lichen planus presents with purplish papules and plaques. It is typically pruritic rather than painful and is much more common on the extremities than the neck. purplish papules and plaques (Choice E) Seborrheic dermatitis presents with erythematous patches associated with greasy scales. It most commonly affects the scalp, ears, eyebrows, and nasolabial folds. greasy scales (Choice F) Tinea barbae can present with papules in the beard area, but the papules are typically scaly or pustular, are often pruritic, and frequently occur in an annular pattern. Educational objective: Pseudofolliculitis barbae presents with small, painful papules in the beard area. It is caused by penetration of the hair shaft into interfollicular skin, often due to shaving of tightly curled hair. Complications include hyperpigmentation, secondary bacterial infection, and keloid formation. Management includes discontinuation of shaving or use of alternative shaving techniques. References: Pseudofolliculitis barbae: a review of current treatment options. (http://www.ncbi.nlm.nih.gov/pubmed/30909328)

A 32-Year-Old Man Comes to the Office Due to a Rash