Pilonidal disease

Pilonidal cysts can be itchy and often very painful, and typically occur between the ages of 15 and 35. or the genital region, though these locations are much rarer. Signs and symptoms may include: • Intermittent pain/discomfort or swelling above the anus or near the tailbone • Opaque yellow (purulent) or bloody discharge from the tailbone area • Unexpected moisture in the tailbone region • Discomfort sitting on the tailbone, doing sit-ups, or riding a bicycle—any activities that roll over the tailbone area Some people with a pilonidal cyst will be asymptomatic. Pilonidal sinus Pilonidal sinus (PNS): a sinus tract, or small channel, that may originate from the source of infection and open to the surface of the skin. Material from the cyst drains through the pilonidal sinus. A pilonidal cyst is usually painful, but if it is a draining sinus, the pressure is relieved and the patient might not feel pain. == Causes ==

Hair insertion is the causative agent of pilonidal cysts. An analysis of 624 patients' cyst hair found that 74% of the hair was rootless, and resembled spiky, razor-cut hair rather than intact body hair. although hairs found in pilonidal sinus tracts have more often been found to originate from the head. Excessive sitting is thought to predispose people to the condition, as sitting increases pressure on the coccygeal region. Trauma is not believed to cause a pilonidal cyst; however, such an event may result in inflammation of an existing cyst. There are cases where this has occurred months after a localized injury to the area. Pilonidal cysts may be caused by a congenital pilonidal dimple. Excessive sweating can also contribute to the formation of a pilonidal cyst: moisture can fill a stretched hair follicle, which helps create a low-oxygen environment that promotes the growth of anaerobic bacteria, often found in pilonidal cysts. The presence of bacteria and low oxygen levels hamper wound healing and exacerbate a developing pilonidal cyst. ==Differential diagnosis==

A pilonidal cyst can resemble a dermoid cyst, a kind of teratoma (germ cell tumor). In particular, a pilonidal cyst in the gluteal cleft can resemble a sacrococcygeal teratoma. Correct diagnosis is important because all teratomas require consultation with an oncologist and complete surgical excision, if possible without any spillage. == Treatment ==

If there is an infection, treatment is generally by incision and drainage just off the midline because incisions in the midline have a hard time healing well. The evidence for elective treatment of pilonidal sinus disease is poor. The most commonly performed surgery is for the pilonidal sinus complex to be surgically excised with the wound often left open to heal. Post-surgical wound packing may be necessary, and packing typically must be replaced daily for four to eight weeks. In some cases, two years may be required for complete granulation to occur. Sometimes the cyst is resolved via surgical marsupialization. A 2018 literature review of 740 records of surgeries that included recurrence rates found that primary midline closure surgeries resulted in a 67.9% recurrence rate within 20 years, and recommended that they should be discontinued due to the high recurrence rate. Incision and drainage had a recurrence rate of 25.9% within 2 years, up to 40.2% in 5 years. Phenol treatment has a recurrence rate of 14.1% at 2 years and 40.4% at 5 years. Surgeons can also excise the sinus and repair it with a reconstructive flap technique, such as a "cleft lift" procedure or Z-plasty, usually done under general anesthetic. This approach is especially useful for complicated or recurring pilonidal disease, leaves little scar tissue, and flattens the region between the buttocks, reducing the risk of recurrence. Pilonidal cysts can recur, and do so more frequently if the surgical wound is sutured in the midline, as opposed to away from the midline, which obliterates the natal cleft and removes the focus of shearing stress. An incision lateral to the intergluteal cleft is therefore preferred, especially given the poor healing of midline incisions in this region. Minimally invasive techniques with no wound and rapid return to full activities have been reported but await double-blind randomized trials. Another technique is to treat the pilonidal sinus with fibrin glue. This technique is of unclear benefit as of 2017 due to insufficient research. The evidence for any treatment is of low quality, and care must be taken not to overinterpret any study in this field. In some cases, the wounds are left open after surgery to heal naturally instead of being closed with stitches. There are a lot of different dressings and topical agents (creams or lotions) that are available to help these open wounds heal. A 2022 systematic review brought together evidence from 11 studies that compared dressings and topical agents for treating open wounds after surgical treatment for pilonidal sinus of the buttocks. The authors concluded that: platelet rich plasma may help wounds to heal quicker compared to sterile gauze; Lietofix skin repair cream may help wounds to heal by 30 days compared to iodine (which helps to reduce bacteria in the wound); but it is not clear whether hydrogel dressings (designed to keep the wound moist) reduce the time it takes wounds to heal compared with cleaning the wound with iodine. File:Pilonidal Cyst.png|Excised pilonidal cyst File:Trephine surgery 1.png|Trephine/biopsy punch minimally invasive surgery for pilonidal disease (1) File:Trephine surgery 2.png|Trephine/biopsy punch minimally invasive surgery for pilonidal disease (2) File:Pilonidal cyst 2 days after surgery.jpg|Pilonidal cyst two days after traditional closed surgery File:Pilonidal cyst and fistula.jpg|alt=Pilonidal disease removed|Anatomy of pilonidal disease removed after trephine or biopsy punch surgery: pilonidal fistula (top) and pilonidal cyst (bottom) == Etymology ==

Pilonidal means 'nest of hair' and is derived from the Latin words for 'hair' () and 'nest' (). The condition was first described by Herbert Mayo in 1833. R. M. Hodges was the first to use the phrase pilonidal cyst to describe the condition in 1880. The condition was widespread in the United States Army during World War II. The condition was termed "Jeep seat" or "Jeep riders' disease", because a large portion of people who were being hospitalized for it rode in Jeeps, and prolonged bumpy rides in the vehicles were believed to have caused the condition due to irritation and pressure on the coccyx. == References ==