Pilonidal Sinus at Lateral Aspect of Neck

Pilonidal sinus disease is seen most commonly in the sacro-coccigeal area. Umbilical pilonidal sinus is a rare form of the condition with few studies about its clinical course and management. The current review is to highlight the presentation and management of umbilical pilonidal sinus. Literature review revealed 25 papers which contained 385 patients complaining from umbilical pilonidal sinus. Chronic discharging sinus and pain were the two most common presenting symptoms. Both conservative and surgical management were effective methods of therapy.


Introduction
The term of pilonidal is coming from Latin words hair (pilus) and nest (nidus). Pilonidal disease (PND) was first described by Hodges in 1880 and is diagnosed by the presence of a characteristic epithelial tract (the sinus) located in the skin of the natal cleft, a short distance behind the anus and commonly containing hair. During Second World War, PND was common in jeep drivers, for that known as Jeep Disease. PND is considered an acquired disease, which mostly seen in the sacrococcygeal region. The disease is frequently seen in young men, people with poor hygiene and those spend most of their time sitting such as drivers and students. It is clinically presented by a classical inflammatory pattern including: local pain, heat, tenderness, fluctuation and erythema. It may also present with local discharge. Uncommon areas include groin, interdigital web, umbilicus, nose, inter mammary area, suprapubic region, clitoris, prepuce, penis, occiput, and on the feet. PND of the neck is a very rare condition. To best of our knowledge, only three cases have been reported in the literature. The aim of this study is to report a case of neck PND occurring in a young man.

Case Report
A 37-year-old male employer from Sulaimaniya presented complaining of intermittent pain and discharge from mid left lateral neck of several months duration, there is a sinus on neck with discharge, he received antibiotics several times, there are periods of remission when there is no pain and discharge and then reappearing after few days.
No diabetic, no hypertensive multiparous. Under local anesthesia, excision and primary closure done and sent for histopathology. After 5 days he comes back, and the sutures removed, after 2 month the patient comes for follow up, wound completely healed with no pain or discharge.
Histopathology shows pilonidal sinus (grooly two pieces of tissue the largest skin and fibro-fatty dark grey, 2 × 1 × 0.5 cm. dissection reveals a sinus tract with hair tuft and necrotic debris, the smallest 0.5 × 0.5 cm.
Microscopic section show skin, subcutaneous tissue and adnexa predominantly few hair follicles, with subcutaneous fatty layer and skeletal muscle bundle, upper dermis showing intense chronic inflammatory infiltrates, deep dermis showing granulation tissue formation with mixed intense inflammation extending deep into subcutaneous fibrofatty layer with prominent necrosis and necrotic and cellular dermis accumulation are seen. Prominent foreign body granuloma formation in the deep dermis and subcutaneous layers with haemorrhages and haemosiderin laden macrophages are seen, no atypia, no malignancy Pictures is consistent with PNS of neck.

Discussion
Eryilmaz et al. suggested predisposing factors for UPS such as hairiness, young age, male sex and poor personal hygiene [1]. The current review confirmed some of these risk factors for developing UPS. According to the result of this review, UPS mostly occurs in male patients (85.5%). The average age of presentation is 36.5 years. Usually PNS occur in hair dressers and drivers as the latter have history of prolonged sitting and the former work manually with and frequently expose to hairs [2]. UPS does not have specific job prediction. It is reported to occur in student, drivers, hair dressers, tailors. Thus, in spite of the fact that several authors did not report the job of their patients which again may indicate that the job does not have impact on the aetiology and development of the disease [3][4][5].
The most common presenting symptom of UPS is chronic discharging sinus (58.4%), rarely associated with bleeding; this is the same scenario of PNS occurring in other areas [6]. According to the literature, there is no standard treatment for UPS. Some authors remove the tuft of hair only, while others offer hair removal, curetting of the cavity, and silver nitrate application for granulomas for non-operative treatment [7]. According to this review, more than half UPS cases are managed conservatively (54.3%). For cases that are resistant to conservative management, surgical excision would be the definitive treatment with reconstruction of the umbilicus [8][9][10].
The strange finding of this review is the residency of the patients. Almost all cases of UPS were reported to occur in Middle East countries. About 90% of UPS occurred in Iran (40.5%), Iraq (34.8%) and Turkey (14.8%) [11][12][13][14][15][16]. High incidence of UPS in these 3 countries may be explained by the cultural and traditional factors. People in these areas believe that umbilicus is a delicate structure and it is dangerous to be manipulated too much! This leads to accumulation of hairs and dirty material with subsequent chronic infection and inflammation and hair penetration. However, more studies with higher statistical power are necessary to confirm and explain this finding. Kareem et al. [11] reported the largest case series of UPS which contained data about 134 patients from Iraq with age range from 17 to 36 years. The number of male patients was 121 and others (13 patients) were female. Surgical intervention was only indicated in two patients [11]. The second largest case series was reported in Iran by Shirangi et al. [16]. It included 60 patients with male to female ratio 55:5. Umbilictomy and reconstruction strategy was used in 30 patients while only excision was performed in others [16]. Sporadically, cases of UPS reported in countries other than Middle East [17][18][19][20]. Haj et al. [20] published the report of 12 patients complaining from UPS from Israel. The paper contained eight males and four females ranging from 18 to 30 years old [20]. All of them were treated with excision under general anesthesia. Ponten et al. [18] reported 3 cases of UPS from Nederland, two male and one female, with age 25, 27, 52 years respectively. Two cases were managed with excision of umbilicus and primary closure while the other treated conservatively [18][19][20].

Conclusion
In conclusion, UPS are more common in male and in Middle East countries especially in Iran, Iraq and Turkey. Chronic discharging sinus and pain are the two main presenting symptoms. Conservative management is the standard method of therapy. When resistant to conservative therapy, surgical excision and reconstruction is the alternative effective management.