LAUSR

Pilonidal sinus disease (PS) is a well-known health problem, mostly in sacrococcygeal region. However, umbilicus as a location of PS is rare clinical entity or better said, often misdiagnosed [1–3]. In 1854, Warren described the first case of umbilical pilonidal sinus (UPS) as a hair cyst [4], and the term UPS was first described by Patey and Williams in 1956 [6]. The incidence and prevalence of UPS is between 0.1 and 0.6% [1, 6]. Although there are two theories in the pathogenesis of the disease, congenital and acquired, several authors of recent studies consider this disease acquired [2, 3, 5]. The UPS begins by hair penetrating the skin, leading to a foreign body reaction, which leads to inflammation (granulation tissue) and formation of the sinus [1–6]. Predisposing factors to develop UPS are male gender, young age, hairiness, family history of pilonidal disease, deep navel, poor personal hygiene, and wearing tight clothes (friction) [1–3, 6]. Body mass index is a questionable predisposing factor, depending on the study [1–3, 6, 7]. The most common symptoms and signs of UPS are wetness of the umbilicus, purulent discharge, pain, bleeding, itching, malodor, swelling, and dermatitis. The UPS can be diagnosed by careful clinical observation, but with unclear cases, computed tomography can be performed. Differential diagnose of the UPS include umbilical hernia, abscess, pyogenic granulomas, umbilicoliths, infection secondary to trauma, benign tumors (navi etc.), metastatic tumors (Sister Mary Joseph nodule etc.), omphalomesenteric duct remnants (Meckel’s diverticulum etc.), anterior cutaneous nerve entrapment syndrome, acute abdomen, and endometriosis in women [1–4, 6, 8]. There are several studies that support conservative treatment for UPS, and surgical treatment only in recurrent cases. Nevertheless, recent studies show the superiority of surgical treatment, especially minimally invasive surgery [1–3, 6, 7, 9].