- Published on
Infectious disease and microbiology – Pilonidal abscess
A pilonidal abscess is an infection of a pilonidal cyst, usually located in the postanal or sacrococcygeal region within the natal cleft. Pilonidal disease is now considered an acquired condition rather than congenital and ranges from asymptomatic pits to painful abscesses and chronic draining sinuses.
The disease is relatively common, with approximately 70,000 new cases annually in the United States. It occurs most often in young adults between 18 and 30 years of age and is significantly more common in males than females, with a male-to-female ratio of about 3:1. Higher rates are reported in Mediterranean populations, whereas the disease is relatively uncommon in East Asia, Oceania, and sub-Saharan Africa.
Several risk factors contribute to pilonidal disease, including male gender, obesity, excessive body hair, poor hygiene, and a deep natal cleft. Although prevention is difficult, maintaining good perianal hygiene and regular hair removal may reduce recurrence and progression.
The pathogenesis involves the formation of a hair follicle pit in the natal cleft, which enlarges and fills with keratin and debris. Hair penetration into the skin triggers a foreign body inflammatory reaction, leading to infection of the surrounding subcutaneous tissue. Chronic disease may result in sinus tract formation, with the direction of hair insertion influencing the tract pattern.
The exact microbial causes are variable, but infections are usually polymicrobial and involve organisms from the skin flora and bowel flora, including anaerobic bacteria.
Clinically, patients typically present with a painful, tender, warm, fluctuant swelling in the sacrococcygeal area during acute infection. Chronic disease may produce persistent or intermittent drainage from midline pits or sinus tracts, with symptoms waxing and waning over weeks.
Diagnosis is mainly clinical and based on physical examination. Characteristic findings include midline pits in the gluteal cleft, usually located approximately 5 cm above the anus. Acute abscesses, chronic sinus tracts, or minimal inflammation may be present. An anorectal examination is important to exclude other conditions.
The differential diagnosis includes both infectious and noninfectious disorders such as perianal abscess, hidradenitis suppurativa, necrotizing fasciitis, furunculosis, herpes simplex infection, syphilis, tuberculosis, anal fistulas, Crohn disease, coccygodynia, and radiation proctitis.
Management depends on the severity and chronicity of disease. Antibiotics alone have a limited role but may be useful in patients with associated cellulitis, systemic illness, or immunosuppression. When used, therapy should include anaerobic coverage. Meticulous local hygiene and hair removal are recommended as supportive measures.
For minimally symptomatic disease, nonsurgical therapies such as phenol or fibrin glue injection combined with hygiene and hair control may be attempted. However, the mainstay of treatment for most acute or chronic cases is surgical management. Limited excision with an off-midline incision and removal of the sinus pits is often sufficient and allows quicker recovery with acceptable recurrence rates. More extensive recurrent or complicated disease may require wide excision and reconstruction with flattening of the natal cleft, although this approach carries higher morbidity.
The overall prognosis is excellent, though recurrence is relatively common and may necessitate repeat or more extensive surgery. Rare complications include large abscesses leading to sepsis and shock, and in very long-standing untreated disease, the development of carcinoma arising from a chronic pilonidal sinus.
A pilonidal abscess is an infection of a pilonidal cyst, usually located in the postanal or sacrococcygeal region within the natal cleft. Pilonidal disease is now considered an acquired condition rather than congenital and ranges from asymptomatic pits to painful abscesses and chronic draining sinuses.
The disease is relatively common, with approximately 70,000 new cases annually in the United States. It occurs most often in young adults between 18 and 30 years of age and is significantly more common in males than females, with a male-to-female ratio of about 3:1. Higher rates are reported in Mediterranean populations, whereas the disease is relatively uncommon in East Asia, Oceania, and sub-Saharan Africa.
Several risk factors contribute to pilonidal disease, including male gender, obesity, excessive body hair, poor hygiene, and a deep natal cleft. Although prevention is difficult, maintaining good perianal hygiene and regular hair removal may reduce recurrence and progression.
The pathogenesis involves the formation of a hair follicle pit in the natal cleft, which enlarges and fills with keratin and debris. Hair penetration into the skin triggers a foreign body inflammatory reaction, leading to infection of the surrounding subcutaneous tissue. Chronic disease may result in sinus tract formation, with the direction of hair insertion influencing the tract pattern.
The exact microbial causes are variable, but infections are usually polymicrobial and involve organisms from the skin flora and bowel flora, including anaerobic bacteria.
Clinically, patients typically present with a painful, tender, warm, fluctuant swelling in the sacrococcygeal area during acute infection. Chronic disease may produce persistent or intermittent drainage from midline pits or sinus tracts, with symptoms waxing and waning over weeks.
Diagnosis is mainly clinical and based on physical examination. Characteristic findings include midline pits in the gluteal cleft, usually located approximately 5 cm above the anus. Acute abscesses, chronic sinus tracts, or minimal inflammation may be present. An anorectal examination is important to exclude other conditions.
The differential diagnosis includes both infectious and noninfectious disorders such as perianal abscess, hidradenitis suppurativa, necrotizing fasciitis, furunculosis, herpes simplex infection, syphilis, tuberculosis, anal fistulas, Crohn disease, coccygodynia, and radiation proctitis.
Management depends on the severity and chronicity of disease. Antibiotics alone have a limited role but may be useful in patients with associated cellulitis, systemic illness, or immunosuppression. When used, therapy should include anaerobic coverage. Meticulous local hygiene and hair removal are recommended as supportive measures.
For minimally symptomatic disease, nonsurgical therapies such as phenol or fibrin glue injection combined with hygiene and hair control may be attempted. However, the mainstay of treatment for most acute or chronic cases is surgical management. Limited excision with an off-midline incision and removal of the sinus pits is often sufficient and allows quicker recovery with acceptable recurrence rates. More extensive recurrent or complicated disease may require wide excision and reconstruction with flattening of the natal cleft, although this approach carries higher morbidity.
The overall prognosis is excellent, though recurrence is relatively common and may necessitate repeat or more extensive surgery. Rare complications include large abscesses leading to sepsis and shock, and in very long-standing untreated disease, the development of carcinoma arising from a chronic pilonidal sinus.
0 Comments
