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Pilonidal Cyst

Cysts Pilonidal

A pilonidal cyst is a fluid-filled swelling which occurs mainly in young males.


This condition normally occurs in the anorectal region and typically presents in any one of the following ways:

Usually, the cyst is asymptomatic; unless it becomes infected and there is complaint of foul smelling discharge along with severe pain and redness at the bottom of the spine. Even at the height of inflammatory symptoms, constitutional symptoms are mild. As the acute abscess resolves, chronic sinus tracts develop towards the skin [5].

If there is a chronic recurring sinus, it is commonly in the midline, about the level of the first piece of coccyx. There is a tuft of hair projecting from the mouth of the sinus. Discharge is often blood stained, and foul smelling from the sinuses. Secondary openings may be present on either side of the midline, sometimes far out onto the buttocks or in the perineum. A sinus can have has many as six openings. Chronic or recurrent abscesses with extensive branching tracts develop in few cases.

Most of the openings occur about 4-8cm away from the anal opening. Unlike a fistula in ano, the sinus passes upwards and forwards towards the sacrum and ends blindly near the bone [6].

Localized Pain
  • When to seek medical advice Call your healthcare provider right away if any of these occur: Pus continues to come from the cyst for 5 days after the incision Increasing redness, local pain, or swelling Fever of 100.4 F (38.0 C) or higher for more than[oregon.providence.org]
  • Pilonidal cysts are described as dermoid cysts containing hair follicles, sebaceous and sweat glands, clinically manifested by a classical inflammatory pattern: local pain, tenderness, heat and erythema 1 . Its etiology remains controversial 1-4 .[scielo.br]
Foul Smelling Discharge
  • Usually, the cyst is asymptomatic; unless it becomes infected and there is complaint of foul smelling discharge along with severe pain and redness at the bottom of the spine.[symptoma.com]
  • Some symptoms of infection include elevating pain around the incision, bleeding, and foul-smelled discharge. Your GP might be able to look for these signs early.[woundcaresociety.org]
Constitutional Symptom
  • Even at the height of inflammatory symptoms, constitutional symptoms are mild. As the acute abscess resolves, chronic sinus tracts develop towards the skin.[symptoma.com]
Recurrent Sinusitis
  • Complicated and recurrent sinuses require wider excision and flap reconstruction. Financial support and sponsorship Nil. Conflicts of interest There are no conflicts of interest. References 1.[ejs.eg.net]
  • Described cases have shown doctors the importance of the utmost vigilance when conducting the dermoscopy of pink nodules, which may suggest amelanocytic melanoma, basal and squamous cell carcinoma, pyogenic granuloma, lymphoma, pseudolymphoma and even[ncbi.nlm.nih.gov]
  • CONCLUSIONS: G-CSF administration, along with BMC mobilization, is feasible and well tolerated in patients undergoing surgery for SPC; clinical results compare favorably with those observed in controls not receiving G-CSF; the results suggest the potential[ncbi.nlm.nih.gov]
  • It suggests to me that these two conditions are part of a spectrum of conditions which have their origin in the way that the spine is formed in the embryo and the skin closes over it. But that is just my guess.[coccyx.org]
  • Breast Cancer Surgeries: Breast Biopsies: When initial tests suggest breast cancer, a breast biopsy is the next step. Our surgeons conduct a variety of biopsy types depending on the situation.[surgneenah.com]
  • Others suggest that bits of hair from other parts of the body can get caught in a small opening in the skin of the lower back and cause this same cycle of inflammation and infection.[luriechildrens.org]
  • The neuropsychological examination showed attention and concentration deficit followed by memory impairment associated with mental and physical lentification, tematic perseverations and conceptual and critical disabilities suggesting a fronto-temporo-lymbic[scielo.br]


Pilonidal cysts require no laboratory tests or imaging techniques. Simple clinical examination is enough for a diagnosis. Clinically, the physician will see a tender cystic swelling above the buttock, which will show all the signs of inflammation. There may be many openings to the cyst. Due to the inflammation, the surrounding skin may show slight cellulitis. It appears like a small cystic acne at the bottom of the spine. Pilonidal cysts cause severe pain if infected.


Treatment depends on the presentation of the case. Ideally, the treatment selected should be a simple procedure with minimum morbidity and faster recovery and healing.

Patients reporting for the first time with mild symptoms can sometimes be treated by conservative measures which include, cleaning of the tract, and removal of the hair from the affected area followed by frequent washing of the affected area. Good personal hygiene is a must.

Incase of an acute abscess, if the above conservative measures fail to bring about resolution of the abscess, the abscess should be opened by a small incision. All the granulation tissue, skin debris and hair should be removed. After complete cleaning of the tract, there is some prospect of curing the lesion. Sometimes post cleaning, phenol is injected into the tract to produce sclerosis of the tract. Wound care has to be done by washing the wound with warm water or Sitz bath. Skin will eventually heal and close provided the area is kept clean and free of hair. In a majority of cases, complete wound heals in one month [7].

For patients with recurrent and persistent pilonidal disease a more invasive form of surgery will be required. Procedures vary from unroofing the sinus tract to excision to possible closure with flaps. In general the difference in surgical techniques involves leaving the wound open after surgery to allow it to heal versus closure of wound during surgery [8].

Marsupialization [9] is another surgical technique that might be done where a slit is made on the abscess and the edges are sutured to form a contionus surface from outside to inside of the cyst, thus allowing the site to remain open and drain freely. Proper wound care and hygiene should be maintained post-surgery to prevent recurrence.


The prognosis in most cases of pilonidal cyst is excellent. Wound healing can be delayed or can get infected. Recurrence occurs in 50% cases.


A pilonidal cyst was considered to be congenital or inborn in nature, where a small depression forms above the buttocks. The origin was considered embryonic [2]. This postulate does not account for pilonidal cyst which occurs in other areas.

Currently, the most accepted theory regarding the etiology and origin is that of an ingrown hair or hair broken by friction against clothes or weight, which collects in the cleft between the buttocks. This hair shaft tends to invade the deeper layers of the skin. As a response to the hair as a foreign body, the body produces an inflammatory reaction. This leads to a hair filled abscess cavity.

Excessive pressure, friction and repeated trauma to the area facilitate entry of the hair shaft in to the layers of the skin.
Risk factors associated with this condition are obese and hirsute individuals. Inactive and prolonged periods of sitting can aggravate this cyst. Poor hygiene may increase the risk.


Pilonidal diseases affect about 26 cases per 100,000 people. There is a male preponderance, where males with this condition outnumber females by a ratio of 4:1. Men are at a higher risk because of their hirsute nature [3].

The age of incidence of appearance of pilonidal cyst is between early puberty till late twenties. It is very rare above 45 years of age.

Sex distribution
Age distribution


The main theory regarded by many is the penetration of the hair shaft into the subcutaneous layers of the skin. Follicular occlusion is considered the main cause. Folliculitis causes oedema which occludes the hair follicle; thus the hair follicle penetrates through the dilated hair follicle. A sinus tract develops which extends into the subcutaneous layers. A foreign body reaction leads to the formation of an abscess. Additional sinuses are common.

Histological sections show a dense inflammatory reaction in the dermis as well as epidermis. Along with inflammation there may be ulceration which can lead to erosion of the layers of the skin.

Histologically, the sinus tract is line by stratified squamous epithelium. Hair shafts are either found loose in the sinus or deeply embedded in the scar tissue. The etiology of foreign body reaction is supported by histology [4].

Cyst is lined with chronic granulation tissue and may contain hair and skin debris. Polymorphs infiltrating the wound may range from plasma cells to lymphocytes. Foreign body giant cells are common.


Proper hygiene should be maintained to prevent reappearance of pilonidal cyst. The area should be kept clean and dry and hair should be removed. Weight management is important.


A pilonidal cyst is a localised, fluid-filled swelling which almost always occurs along the coccyx near the natal cleft of the buttocks. The main contents of the cyst are hair shafts and skin debris. Hair penetrates into the deeper layers of the skin. Most of these cysts are asymptomatic, unless they become infected resulting in abscess and sinus formation. This results in severe pain and tenderness.

Pilonidal diseases include the entire spectrum of clinical presentation ranging from an asymptomatic cyst and sinus to a large painful abscess mainly of the sacrococcygeal region. Other lesser common sites of pilonidal cyst are axilla, navel and genitalia [1].

These cysts require surgical intervention, though chances of reoccurrence are common.

Patient Information

Pilonidal cyst is a small swelling that occurs at the bottom of the spine, in the cleft at the top of the buttocks. It causes severe pain if it becomes infected which results in severe foul smelling discharge. It may initially appear as a depression; once it gets infected it appears like a pimple.

It occurs more in men and rarely happens as age progresses. The exact origin is not known and is said to be mainly due to combination of various factors of excessive hair growth, pressure and prolonged sitting.

Pilonidal cyst may not be noticeable at first and will simply look like a pimple like depression, however once infection sets in, a fluid-filled swelling will be formed. There will be severe pain, redness and discharge which may be blood stained may ooze. A sinus tract will follow with many openings on the surface of the skin. These sinuses tend to appear repeatedly.

A medical health provider can easily diagnose the condition by a simple physical examination. Treatment depends on the severity, in case there is no symptoms conservative treatment in form of broad spectrum antibiotics is given. If severe infection is present along with pain, a small incision along with drainage is done. This is a simple and less invasive procedure.

Recurrent pilonidal sinuses require a surgery which mainly excises the entire cyst with the sinus tract. Post operative care is very important, to enable the wound to heal faster. Usually, a pilonidal cyst clears within 4-10 weeks.

Preventive measures in form of personal hygiene, hair removal and weight loss are recommended. Pilonidal cyst have very good recovery rate with correct medical care and preventive care.



  1. Rao AR, Sharma M, Thyveetil M, Karim OM. Penis: An Unusual Site for Pilonidal Sinus. Int Urol Nephrol. 2006;38(3-4):607-8. 
  2. da Silva JH. Pilonidal cyst: cause and treatment. Dis Colon Rectum. 2000 Aug;43(8): 1146–56.
  3. Hodges RM. Pilonidal sinus. The Boston Medical and Surgical Journal. 1880, 103: 485–586.
  4. Klass A. The So-Called Pilo-Nidal Sinus. Canadian Medical Association. 1956 Nov 1;75(9): 737–742.
  5. Timmons J. Diagnosis, treatment and nursing management of patients with pilonidal sinus disease. Nursing Standard. 2007 Sep 5;21(52):48-56; quiz 58.
  6. Abramson DJ. Outpatient Management of Pilonidal Sinuses: Excision and semiprimary closure technic. Mi Med. 1978 Nov; 143 (11): 753–7.
  7. Bascom J, Bascom T. Failed Pilonidal Surgery. Arch Surg. 2002 Oct;137 (10): 1146–50.
  8. McCallum IJD, King PM, Bruce J. Healing by primary closure versus open healing after surgery for pilonidal sinus: systematic review and meta-analysis. Br Med J. 2008;336:868-71.
  9. Roth RF, Moorman WL. Treatment of pilonidal sinus and cyst by conservative excision and W-plasty closure. Plast Reconstr Surg. 1977 Sep;60(3):412–15.

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Last updated: 2018-06-22 10:52