Umbilical Pilonidal Sinus, an Underestimated and Little-Known Clinical Entity: Report of Two Cases

Background

Umbilical pilonidal sinus (UPS) is still a little known entity, and only recently (2016) has there been a high-level evidence to support its occurrence. Although UPS is easily diagnosed, it is frequently overlooked in routine clinical practice due to lack of awareness of the condition by physicians.

Treatment of UPS depends on the disease severity, ranging from improved personal hygiene [1,2] to surgical excision of the affected part of the umbilical complex [3,4]. Extreme care is needed to avoid affecting the aesthetics of the umbilicus if surgery is required, particularly in women [3].

UPS is extremely uncommon in women; however, we report two cases, one in a man and one in a woman.

Case Report

SURGICAL TREATMENT:

Since previous conservative treatment attempts had failed, surgical interventions were decided for both cases, as previously described [3]. A written informed consent was obtained from both patients for the surgery. Following the administration of a single dose of prophylactic intravenous antibiotics, local anesthesia was performed under sedation. Skin incisions were made using a radio-surgical hand piece with a fine needle electrode tip attached. A precise circular skin incision was made 3 to 5 mm below the umbilical ostium through the sub-cutaneous fat toward the linea alba, posterior to the umbilicus. The inner third of the umbilical complex containing the pilonidal sinus and tracts was removed after detaching all deep connections to the fascial layer. The deep subcutaneous tissue was approximated with an absorbable purse-string suture. The skin was left to heal by secondary intention to avoid infection. A ball of gauze with antibiotic ointment was placed over the wound to re-shape the navel and was kept in place for two days.

Specimens were sent to the pathology department (Figure 1C) and diagnosis of UPS was confirmed histopathologically. Both patients were discharged within a few hours, with antibiotics and analgesics. Recommended wound care consisted of washing, drying, and dressing the wound daily. Wounds healed in 2–3 weeks with acceptable cosmetic results and high patient satisfaction (Figure 2). The patients were followed for more than two years without any signs of recurrence.

Discussion

More than 90% of UPS cases are young men with deep navels and abundant body hair [1–5]. Case 1 depicts these typical characteristics. UPS may also be observed in women with absent or minimal body hair and without a deep navel [1–3], as seen in our second case. Therefore, unless proven otherwise, in a patient presenting with a history of intermittent discharge, itching, pain, or bleeding from the umbilicus, and the presence of granulation tissue with or without protruding hair and periumbilical dermatitis (Figure 1), the diagnosis should be UPS, even in female patients. Laboratory and/or radiologic investigations are only reserved for complications or differential diagnosis from other pathologies, such as umbilical hernia, granuloma, dermoid cyst, urachal and omphalomesenteric anomalies, umbilical endometriosis, and benign and malignant neoplasms [6].

Approximately 85% of patients with UPS are 10–30 years old. UPS is very rare in other age groups [3]. High occurrence in young men could be because body hair growth naturally begins with puberty and peaks after age 20. Higher depth of the umbilicus makes it a natural target for hair accumulation. Additionally, softness, maceration, erosions, and wide pores make the umbilical skin very vulnerable to hair insertion. Once umbilical skin is penetrated by hair roots, a foreign body inflammatory response begins. Edema, moisture, and reduced skin integrity further facilitates the insertion of new hair shafts into the forming sinus tracts.

Asymptomatic disease discovered incidentally can be managed by improving personal hygiene which includes the shaving of the surrounding skin, extracting all protruding hairs, and keeping the umbilicus dry. For those presenting with acute abscess or severe infection, simple drainage and curetting of the abscess, removing hairs, and packing the wound daily with appropriate antibiotics is the preferred treatment [1,2,7]. Since the infection is usually polymicrobial, broad-spectrum antibiotics (i.e., sultamicillin 750 mg and ornidazole 500 mg twice per day orally) should be used for 1 or 2 weeks in conjunction with wound care until the infection subsides. In patients with symptomatic chronic intermittent disease, surgical treatment (ST) has shown to be more effective than conservative treatment [3,4]. Despite multiple attempts at CT, 28% patients present with recurrence and 32% do not heal at the two-year follow-up. However, ST has a better result, with 98% recurrence-free rate for the first attempt and 100% for the second attempt [3].

Due to the difficulties in making a correct diagnosis, there are patients who have undergone extreme surgical procedures including total umbilectomy and diagnostic laparoscopy [7]. However, total umbilectomy is not recommended, only the deeper third of navel, containing the sinus tracts and infected tissues should be removed with the aim of preserving the general appearance of umbilicus (Figure 2) [3]. Since the umbilicus is a component of cosmetic appearance for many people, it has been postulated that the preference of surgeons towards CT is reasonable [8]. However, surgeons’ fear of bad cosmetic appearance after ST may be eliminated with the umbilicus preserving surgical technique described here. Thus, it is important to inform patients objectively when reaching a joint decision with them on treatment options. UPS is diagnosed mainly by clinical examination; however, it must also be confirmed histopathologically. Because a spectrum of pathologies can affect the umbilicus and mimic UPS [6], all excised specimens should be sent for histopathologic examination, especially when dealing with a macroscopically suspicious lesion [8].

Conclusions

UPS could easily be misdiagnosed and mistreated due to its rarity and lack of awareness of the condition by physicians. Diagnosis is easy to establish with physical examination and a detailed history. Treatment of choice for chronic, intermittent cases is surgical removal of the affected portion; paying special attention to cosmetic appearance.