Pilonidal sinus is a chronic inflammatory disease caused by the penetration of hair into the skin. Most often, it is located in the intergluteal area, but it may also develop at a different location. It is usually caused by the penetration of human hair, but animal hair can alaso cause it in rare cases. In the world publications, there are reports of the disease in other, often distant locations, e.g. the suprapubic area, armpit, foot, penis, umbilicus, eyelid, clitoris, intermammary cleft, nose, or scar after removing a Tenckhoff catheter. Usually, it is human hair that causes the formation of pilonidal sinus, but the literature also reports cases caused by animal hair in people who shear sheep. There is no other Polish publication describing pilonidal sinus of animal origin. The article presents a case of atypical pilonidal sinus caused by animal hair, located between the fingers of the patient who is professionally involved in shearing dogs. In the presented clinical case, treatment involved staged fistulotomy with the use of surgical thread. The patient was cured and full function of the hand was preserved. Staged fistulotomy is a safe procedure and can be used to treat pilonidal sinus of the hand.
