Pilonidal cysts and boils are two conditions that cause noticeable changes in or on the skin. Each of these disorders has its own symptoms, underlying causes and typical locations.
Pilonidal cysts are pockets within the skin typically filled with skin debris, hair and abnormal tissue, according to the Mayo Clinic. In almost all cases, they occur at the top of the buttocks in the area of the tailbone.
Boils (furuncles) form as a result of an infection that affects the hair follicles and nearby skin, according to the U.S. National Library of Medicine. Although they can occur anywhere on the body, they most commonly form on the neck, face, armpit, thighs and buttocks.
Pilonidal Cyst Causes
The Mayo Clinic lists potential causes of pilonidal cysts that include an autoimmune reaction to loose hairs that penetrate the skin’s surface and the rupture of hair follicles in the skin.
Boils most commonly result from broken hair follicles in the presence of Staphylococcus aureus bacteria. Infection from other bacteria and fungi may also occur.
Pilonidal Cyst Symptoms
Pilonidal cysts may occur without obvious symptoms, but may also become infected, with symptoms including pain, redness, swelling and pus formation.
Symptoms of boils include pain and a raised nodule filled with dead tissue and pus.