PD was first described in a young woman by Herbert Mayo in 1833 [10, 11]. Although PD is commonly diagnosed in the sacrococcygeal region, it can also occur in some other parts of the body such as the umbilicus, forehead, scalp, clitoris, interdigital area, penis, abdomen, neck, and axilla [12]. Previously, it was considered that PD is a congenital disease. Nowadays, although the pathophysiology of PD has not been clearly identified yet, it is considered an acquired disease [13–15]. PD is thought to originate from a granulomatous reaction caused by hair penetrating into the subcutaneous tissue [12, 16, 17]. According to Karydakis, three major factors contribute to the penetration of hair into the subcutaneous tissue: (i) the substance that penetrates, which consists of loose hair; (ii) a certain force that causes the penetration of hair, (iii) the susceptibility of the skin in the specific area [13]. The etiological factors of PD can be listed as; deep natal cleft, prolonged sitting (including traveling or driving), excessive body hair, poor local hygiene, and obesity [16–18].
There are several treatment methods for PD, but there is not a single definitive treatment modality [19]. Each treatment modality has its own advantages and disadvantages. The gold standard treatment method should provide less pain, shorter hospital stay, low complication, and recurrence rates, and quicker return to daily life [16, 20]. Surgical techniques involve skin closure after surgical resection of the sinus cavity from the presacral fascia layer. Various techniques have been performed for skin closure, these are Z-plasty, W-Plasty, V-Y Plasty, Karydakis technique, Bascom flap, Limberg flap, and marsupialization. These surgical techniques are often associated with increased morbidity, high recurrence rates, and long hospital stays [13, 18]. In addition, the tissue loss after these surgical interventions creates difficulty in managing the recurrent disease [19].
Excision of the sinus cavity and associated tracts followed by primary closure or secondary wound healing is the most preferred method for surgical treatment. Surgical procedures require general anesthesia and hospital stay as a disadvantage [21]. In addition to classical surgical techniques, currently, minimally invasive techniques such as sinotomy, sinusectomy, laser cauterization, fibrin sealant, and endoscopic-video-assisted treatments are performed as the primary treatment option [7, 13, 22].
Phenol treatment, injection of 80% phenol into the sinus tract, was described by Maurice and Greenwood in 1964 and is the most performed local treatment option [23]. Controlled chemical destruction of sinus epithelium is aimed via the phenol injection. Silver nitrate (SN) usage is another chemical cauterization technique with the same treatment principles as phenol injection. SN causes destruction, stimulates fibrosis, and closure of the sinus tract via granulation with no need for excision. It also reduces the microbial burden inside the tract through its antimicrobial effect. There is not any proven serious, permanent side effect of SN. While silver metal combinations are toxic to pathogens, their toxicity is lower in healthy tissues [24, 25].
Sozen et al. [12] and Kurt et al. [26] showed lower recurrence rates after SN application on umbilical PD. Kanat et al. [16] reported a study with a single-session application of SN on 45 patients. In this study, monthly follow-up of patients was done, and if any orifice was observed during the follow-up, the application was repeated. Complete wound healing with no discharge and no pain at the end of 12 months was considered as a cure. The results showed a success rate of over 90% in a median 29-month follow-up. Kocamaz et al. [24] compared the results of phenol application (50 patients) and SN application (40 patients) in their study. Similar to the study of Kanat et al. [16], in the SN group, a single session SN application was performed for each patient, monthly routine follow-up was done, and the cure was described as complete wound healing with no discharge, pain, or complaints at the end of the 12-month follow-up. The success rate of SN application was found 95% which was the same as the phenol application.
In this study, we performed SN application in three sessions, different from the literature, and the number of patients was parallel to the literature. While the duration of SN stick application was not specified by Kanat et al. [16], Kocamaz et al. [24] reported this as one to two minutes. This was about 10 seconds in our study. Postprocedural pain status and analgesic usage were not mentioned in other studies. The reason for the high analgesic usage rates in our study might be the shorter SN stick application time on tissue or the lack of local anesthesia usage at the second and third sessions.
The importance of orifice dilatation or the excision of the pit was emphasized and recommended in order to clean the hair in the sinus and to perform the treatment without damaging the skin around the orifice in some other chemical cauterization studies [21,27,28]. Hair removal is a common point of all PD treatment options, and it is important for preventing recurrence. This can be done with creams, waxing, epilators, shaving, and laser depilation [21].
The limitations of this study were the limited number of patients and short follow-up.