Pilonidal sinus

Pilonidal sinus is a small hole or tunnel in the skin, usually at the top of the buttocks where they divide (the natal cleft). It can fill with fluid or pus, causing the formation of a cyst or abscess. It can also lead to the formation of a sinus tract, a channel underneath the skin that connects the cyst to the surface of the skin.

Causes

The exact cause of pilonidal sinus is not known, but it's thought to be caused by loose hairs that penetrate the skin. The body considers this hair as a foreign substance, and launches an immune response against it, which leads to the formation of a cyst around the hair.

Symptoms

Symptoms of pilonidal sinus include pain and swelling at the bottom of the spine, redness and warmth, pus or blood draining from the abscess, and a foul smell. In some cases, it can also cause a low-grade fever.

Diagnosis

Diagnosis of pilonidal sinus is usually based on the symptoms and a physical examination. In some cases, a biopsy may be performed to rule out other conditions.

Treatment

Treatment for pilonidal sinus depends on the severity of the condition. If the sinus is not infected, it can be managed with good hygiene and hair removal. If it's infected, it may need to be drained. In severe cases, surgery may be required to remove the sinus.

Prevention

Prevention of pilonidal sinus includes maintaining good hygiene, avoiding prolonged sitting, and removing hair in the area.

See also

• Cyst
• Abscess
• Sinus tract
• Biopsy