Pilonidal disease

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Pilonidal disease
Other namesPilonidal cyst, pilonidal abscess, pilonidal sinus, sacrococcygeal cyst / fistula
Pilonidal abscess.jpg
Acute pilonidal disease (abscess) in the upper gluteal cleft
Specialty General surgery, colorectal surgery
Symptoms Pain, swelling, redness, drainage of fluid [1]
Usual onsetYoung adulthood [2]
CausesIngrown hair in the natal cleft
Risk factors Obesity, family history, greater amounts of hair (hirsutism), not enough exercise [2]
Diagnostic method Based on symptoms and examination [2]
Differential diagnosis Hidradenitis suppurativa, perianal abscess, folliculitis [2]
PreventionShaving the area [1]
Treatment Incision and drainage, [2] surgical removal
Frequency3 per 10,000 per year [2]

Pilonidal disease is a type of skin infection which typically occurs as a cyst between the cheeks of the buttocks and often at the upper end. [1] [3] Symptoms may include pain, swelling, and redness. [1] There may also be drainage of fluid, but rarely a fever. [1] [2]

Contents

Risk factors include obesity, family history, prolonged sitting, greater amounts of hair, and not enough exercise. [2] The underlying mechanism is believed to involve a mechanical process where hair and skin debris get sucked into the subcutaneous tissues through skin openings called pits. [2] Diagnosis is based on symptoms and examination. [2]

If there is infection, treatment is generally by incision and drainage just off the midline. [1] [2] Shaving the area and laser hair removal may prevent recurrence. [1] [4] More extensive surgery may be required if the disease recurs. [1] Antibiotics are usually not needed. [2] Without treatment the condition may remain long term. [1]

About 3 per 10,000 people per year are affected, and it occurs more often in males than females. [2] Young adults are most commonly affected. [2] The term pilonidal means 'nest of hair'. [1] The condition was first described in 1833. [1]

Signs and symptoms

Two pilonidal fistulous openings (circled) that have formed in the gluteal cleft. Two pilonidal cysts in the natal cleft.jpg
Two pilonidal fistulous openings (circled) that have formed in the gluteal cleft.

Pilonidal cysts can be itchy and often very painful, and typically occur between the ages of 15 and 35. [5] Although usually found near the coccyx, the condition can also affect the navel, armpit, the cheek, [6] or the genital region, [7] though these locations are much rarer.

Signs and symptoms may include: [8]

Some people with a pilonidal cyst will be asymptomatic. [9]

Pilonidal sinus

Pilonidal sinus (PNS): is a sinus tract, or small channel, that may originate from the source of infection and open to the surface of the skin. [10] 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 patient might not feel pain.

Causes

Hair insertion is the causative agent of pilonidal cysts. [11] [12] 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. [11] One proposed cause is ingrown hair, [13] 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 can occur months after a localized injury to the area.

Pilonidal cysts may be caused by a congenital pilonidal dimple. [14]

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 forming pilonidal cyst. [15]

Differential diagnosis

Relative incidence of cutaneous cysts. Pilonidal cyst is labeled near top. Relative incidence of cutaneous cysts.jpg
Relative incidence of cutaneous cysts. Pilonidal cyst is labeled near top.

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 infection, treatment is generally by incision and drainage just off the midline because incisions in the midline have a hard time healing well. [1] [2] Following five simple rules has been known to prevent recurring inflammations for some people and avoid surgery: 1. Avoiding chairs and car seats that put pressure on the coccyx; 2. Being of average weight, preferably with low BMI; 3. Keeping the area clean; 4. Keeping the area dry by wearing exclusively cotton garments; 5. Keeping the area completely hair free, for example, by regularly using an IPL hair removal device. [16]

The evidence for elective treatment of pilonidal sinus disease is poor. [17] 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. [18]

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. [19] 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. [19] A 2024 study involving 667 people found that, compared with tissue-removing surgery, minor procedures (such as draining and pit-picking) were associated with less pain, fewer complications and a faster recovery. However, minor surgeries were less likely to resolve the condition. [20] [21]

Surgeons can also excise the sinus and repair 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. [15] This approach typically results in a more rapid recovery than the traditional surgery, however there are fewer surgeons trained in the cleft lift procedure and it consequently may not be as accessible to patients, depending on their location. Meta-analysis shows recurrence rates were lower in open healing than with primary closure (RR 0.60, 95% CI 0.42 to 0.87), at the expense of healing time. [22] 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 randomised trials. [23]

Another technique is to treat pilonidal sinus with fibrin glue. This technique is of unclear benefit as of 2017 due to insufficient research. [24] The evidence for any treatment is of low quality, and care must be taken not to over interpret any study in this field. [17]

Since the 2010s, a number of minimally invasive techniques have been developed, with the purpose of minimising the impact of surgery on patients and of achieving less pain and shorter recovery times. [25]

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 for helping these open wounds to 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. [26] 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. [26]

Endoscopic pilonidal treatment, which uses a small camera to guide the surgeon in removing hair, is a newer method of treatment that has minimal pain and quick healing compared to surgery. A literature review of 497 patients found that the average endoscopic operation time was 34.7 minutes, and the average healing time was 32.9 days. Failure occurred in 8% of patients, who had persistent disease or recurrence. [27]

Etymology

Pilonidal means 'nest of hair' and is derived from the Latin words for 'hair' (pilus) and 'nest' (nidus). [5] The condition was first described by Herbert Mayo in 1833. [28] R. M. Hodges was the first to use the phrase pilonidal cyst to describe the condition in 1880. [29] [30]

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.

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References

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  4. ↑ "Pilonidal Cyst Laser Hair Removal". Cure Pilonidal Cyst. Archived from the original on 2022-07-06. Retrieved 2021-08-23.
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  6. ↑ Adhikari BN, Khatiwada S, Bhattarai A (February 2021). "Pilonidal sinus of the cheek: an extremely rare clinical entity-case report and brief review of the literature". Journal of Medical Case Reports. 15 (1): 64. doi: 10.1186/s13256-020-02561-z . PMC   7874666 . PMID   33563340.
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  8. ↑ Sternberg J. "What Is Pilonidal Disease". Archived from the original on November 11, 2014. Retrieved November 14, 2014.
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  10. ↑ "PNS Acronyms". thefreedictionary.com. Archived from the original on 2018-01-04. Retrieved 2018-01-03.
  11. 1 2 Bosche F, Luedi MM, van der Zypen D, Moersdorf P, Krapohl B, Doll D (February 2018). "The Hair in the Sinus: Sharp-Ended Rootless Head Hair Fragments can be Found in Large Amounts in Pilonidal Sinus Nests". World Journal of Surgery. 42 (2): 567–573. doi:10.1007/s00268-017-4093-5. PMID   28639004. S2CID   4705771.
  12. ↑ Karydakis GE (May 1992). "Easy and successful treatment of pilonidal sinus after explanation of its causative process". The Australian and New Zealand Journal of Surgery. 62 (5): 385–389. doi:10.1111/j.1445-2197.1992.tb07208.x. PMID   1575660.
  13. ↑ "Pilonidal Cyst: Causes". Mayo Clinic. December 5, 2012. Archived from the original on October 25, 2008. Retrieved February 8, 2013.
  14. ↑ da Silva JH (August 2000). "Pilonidal cyst: cause and treatment". Diseases of the Colon and Rectum. 43 (8): 1146–1156. doi:10.1007/bf02236564. PMID   10950015. S2CID   189796851.
  15. 1 2 Bascom J, Bascom T (October 2002). "Failed pilonidal surgery: new paradigm and new operation leading to cures". Archives of Surgery. 137 (10): 1146–50, discussion 1151. doi:10.1001/archsurg.137.10.1146. PMID   12361421.
  16. ↑ Shafigh Y, Beheshti A, Charkhchian M, Rad FS (April 2014). "Successful treatment of pilonidal disease by intense pulsed light device". Advances in Clinical and Experimental Medicine. 23 (2): 277–282. doi: 10.17219/acem/37077 . PMID   24913119.
  17. 1 2 Brown SR, Lund JN (December 2019). "The evidence base for pilonidal sinus surgery is the pits". Techniques in Coloproctology. 23 (12): 1173–1175. doi:10.1007/s10151-019-02116-5. PMC   6890656 . PMID   31754976.
  18. ↑ Patel H, Lee M, Bloom I, Allen-Mersh TG (March 1999). "Prolonged delay in healing after surgical treatment of pilonidal sinus is avoidable". Colorectal Disease. 1 (2): 107–110. doi:10.1046/j.1463-1318.1999.00030.x. PMID   23577714. S2CID   206172705.
  19. 1 2 Stauffer VK, Luedi MM, Kauf P, Schmid M, Diekmann M, Wieferich K, et al. (February 2018). "Common surgical procedures in pilonidal sinus disease: A meta-analysis, merged data analysis, and comprehensive study on recurrence". Scientific Reports. 8 (1): 3058. Bibcode:2018NatSR...8.3058S. doi:10.1038/s41598-018-20143-4. PMC   5814421 . PMID   29449548.
  20. ↑ Brown, Steven; Hind, Daniel; Strong, Emily; Bradburn, Mike; Din, Farhat Vanessa Nasim; Lee, Ellen; Lee, Matthew J.; Lund, Jonathan; Moffatt, Christine; Morton, Jonathan; Senapati, Asha; Shackley, Philip; Vaughan-Shaw, Peter; Wysocki, Arkadiusz Peter; Callaghan, Tia (2024-07-17). "Treatment options for patients with pilonidal sinus disease: PITSTOP, a mixed-methods evaluation". Health Technology Assessment. 28 (33): 1–113. doi:10.3310/KFDQ2017. ISSN   2046-4924.
  21. ↑ "Pilonidal sinus: what type of surgery is best?". NIHR Evidence. 17 October 2024.
  22. ↑ Al-Khamis A, McCallum I, King PM, Bruce J (January 2010). "Healing by primary versus secondary intention after surgical treatment for pilonidal sinus". The Cochrane Database of Systematic Reviews. 2010 (1): CD006213. doi:10.1002/14651858.CD006213.pub3. PMC   7055199 . PMID   20091589.
  23. ↑ Hardy EJ, Herrod PJ, Doleman B, Phillips HG, Ranat R, Lund JN (November 2019). "Surgical interventions for the treatment of sacrococcygeal pilonidal sinus disease in children: A systematic review and meta-analysis". Journal of Pediatric Surgery. 54 (11): 2222–2233. doi:10.1016/j.jpedsurg.2019.02.058. PMID   30940347. S2CID   88464026.
  24. ↑ Lund J, Tou S, Doleman B, Williams JP (January 2017). "Fibrin glue for pilonidal sinus disease". The Cochrane Database of Systematic Reviews. 1 (1): CD011923. doi:10.1002/14651858.CD011923.pub2. PMC   6464784 . PMID   28085995.
  25. ↑ Basso L, Pietroletti R, Micarelli A, Bicaj A, Costi U, Crocetti D, et al. (August 2022). "The impact of experience on recurrence rates after biopsy punch excision for pilonidal disease". Colorectal Disease. 24 (8): 984–991. doi:10.1111/codi.16126. PMC   9541250 . PMID   35344244.
  26. 1 2 Herrod PJ, Doleman B, Hardy EJ, Hardy P, Maloney T, Williams JP, Lund JN, et al. (Cochrane Wounds Group) (May 2022). "Dressings and topical agents for the management of open wounds after surgical treatment for sacrococcygeal pilonidal sinus". The Cochrane Database of Systematic Reviews. 2022 (5): CD013439. doi:10.1002/14651858.CD013439.pub2. PMC   9121912 . PMID   35593897.
  27. ↑ Emile SH, Elfeki H, Shalaby M, Sakr A, Giaccaglia V, Sileri P, Wexner SD (September 2018). "Endoscopic pilonidal sinus treatment: a systematic review and meta-analysis". Surgical Endoscopy. 32 (9): 3754–3762. doi:10.1007/s00464-018-6157-5. PMID   29603009. S2CID   4472852.
  28. ↑ Lanigan M (September 27, 2012). "Pilonidal Cyst and Sinus". Medscape . WebMD. Archived from the original on October 22, 2008. Retrieved February 8, 2013.
  29. ↑ Hodges RM (1880). "Pilonidal sinus". The Boston Medical and Surgical Journal . 103 (21): 485–586. doi:10.1056/NEJM188011181032101. Archived (PDF) from the original on 2021-08-28. Retrieved 2020-02-10.
  30. ↑ Kanerva L, Elsner P, Wahlberg JE, Maibach HI, eds. (2000). Handbook of occupational dermatology. Berlin: Springer. ISBN   3-540-64046-0.
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