A 35-year-old man comes to the urgent care center with 2 days of pain in the intergluteal area made worse with sitting. For the last several years, he has had staining of the underwear in that area with clear fluid. The patient has no other symptoms or medical conditions. His temperature is 37 C (98.6 F). Physical examination shows mild swelling and tenderness at the midline immediately below the coccyx with a small sinus opening.

Which of the following is the most likely diagnosis?

Question

A 35-year-old man comes to the urgent care center with 2 days of pain in the intergluteal area made worse with sitting. For the last several years, he has had staining of the underwear in that area with clear fluid. The patient has no other symptoms or medical conditions. His temperature is 37 C (98.6 F) . Physical examination shows mild swelling and tenderness at the midline immediately below the coccyx with a small sinus opening.

Which of the following is the most likely diagnosis?

Quizplus · Accepted Answer

This patient's presentation suggests intergluteal pilonidal disease, a skin and/or subcutaneous infection near the natal cleft of the buttocks. Risk factors for pilonidal disease include obesity, local trauma, prolonged sitting, and family history. Patients typically develop stretching of the natal cleft that damages the underlying hair follicles and creates an opening (pore or sinus) that can become infected. Patients can be asymptomatic or develop sudden onset of mild intergluteal pain with sitting or bending. Chronic disease can present with a tender mass or sinus with purulent, mucoid, or bloody drainage. Diagnosis is made clinically without the need for imaging or laboratory studies. Initial management in most cases consists of incision and drainage, although many patients will benefit from surgical excision. (Choice A) Condylomata acuminata (genital warts) is due to human papillomavirus and usually presents as skin-colored, white, or gray verrucous and filiform papules. Although the papules can occur in the anal/perianal area, they are usually not associated with sinus tract formation. Condylomata acuminata (Choice B) Crohn disease can be associated with perianal complications such as fissures, tags, or abscesses. However, this patient has no other findings (eg, gastrointestinal bleeding, diarrhea, anal pain) to suggest Crohn disease. Crohn disease (Choice C) Hidradenitis suppurativa typically presents with chronic, painful, swollen, and inflamed lesions in intertriginous areas (eg, axillae, inguinal region). Although it can cause perirectal disease with purulent drainage and sinus tracts similar to pilonidal disease, hidradenitis suppurativa usually does not affect the gluteal cleft area. Hidradenitis suppurativa (Choice D) Perianal abscess typically presents with severe anal or rectal pain, systemic findings (eg, fever, malaise), and perianal erythema with fluctuance. However, pilonidal disease typically involves the coccyx region instead of the perianal area. Educational objective: Pilonidal disease is a skin and/or subcutaneous infection near the natal cleft of the buttocks. Patients can be asymptomatic or develop sudden onset of mild intergluteal pain with sitting or bending. Chronic disease can present with a tender mass or sinus with purulent, mucoid, or bloody drainage. __________ References: Pilonidal sinus disease. (http://www.ncbi.nlm.nih.gov/pubmed/23911903)

A 35-Year-Old Man Comes to the Urgent Care Center with 2