A perineal groove is a rare and usually uncomplicated congenital malformation of the perineum characterized by a wet sulcus that extends from the posterior fourchette to the anus. Of 12 previously described cases, only 1 has been reported in the dermatology literature.1- 6
A 4-month-old term white girl was referred to pediatric dermatology by her pediatrician and a pediatric surgeon for evaluation of a congenital perineal lesion. The mother’s pregnancy was unremarkable, and the infant was healthy. The lesion had been stable and uncomplicated since birth. Barrier creams were attempted for presumed diaper dermatitis without response. Physical examination showed a well-demarcated, erythematous, superficial ulcer anterior to the anus (Figure, A). A fungal culture was negative. At the 1-month follow-up, the ulcer remained unchanged. The infant underwent 1 treatment with pulsed-dye laser for the possible diagnosis of ulcerated hemangioma, which led to improvement in the erythema. Six months later, when the ulceration remained largely unchanged, a skin biopsy was performed. Histologic specimens showed hyperkeratosis, hypergranulation, fibrosis, and vascular dilatation. Abdominal and pelvic ultrasonography was performed to rule out associated anomalies, and the findings were normal. A diagnosis of perineal groove was ultimately made clinically without further intervention. The lesion remained asymptomatic and stable at last follow-up, patient age, 16 months.
A, Well-demarcated, erythematous, superficial ulcer anterior to the anus in patient 1. B, Well-demarcated, erythematous ulcer anterior to the anus in patient 2.
A 6-month-old and otherwise healthy white girl was sent to pediatric dermatology clinic by her pediatrician for evaluation of a stable, asymptomatic perineal lesion noted at age 2 months. The mother had an unremarkable pregnancy history except for diet-controlled gestational diabetes. The infant had been treated with multiple barrier and antifungal creams without improvement. Physical examination showed a well-demarcated, erythematous ulcer anterior to the anus (Figure, B). Cultures for bacteria and fungus were negative. The diagnosis of perineal groove was made clinically. A skin biopsy and imaging were offered, but the parents declined. At age 14 months, the lesion was less pronounced and remained asymptomatic.
A perineal groove is a rare congenital anomaly that occurs mostly in female patients, with only 1 reported case in a male patient.1 While the exact pathogenesis remains unclear, a perineal groove may result from faulty development of the embryonic cloaca, the perineal raphe’s failure to fuse, or a defect in the development of the uroanal septum.3,4
A perineal groove may initially be confused with an ulcerated hemangioma, irritant dermatitis, infection, lichen sclerosis, perianal pyramidal protrusion, trauma, or sexual abuse, often rendering the diagnosis difficult. The diagnosis is made clinically, with biopsy rarely performed. While histologic findings vary, nonkeratinizing squamous epithelium with an intervening area of rectal type or transitional epithelium has been reported from excision specimens.1,3
Imaging for associated regional anomalies may be considered, although such anomalies are believed to be rare. In the literature, there is 1 case of a perineal groove associated with hypospadias and a bifid scrotum, 1 with an ectopic anus, and another with an associated urinary tract anomaly.1,2,6
A perineal groove may persist or resolve spontaneously within a year of presentation.3,4 While most lesions remain asymptomatic, rare complications of constipation, urinary tract infections, and skin infections have been reported.2 Treatment is generally not needed unless lesions cause recurrent problems such as infections or mucous drainage.4,6 Surgery may also be considered for cosmetic reasons. If surgical treatment is pursued, it is recommended only after the age of 2 years, when the potential for self-healing has passed.2
We report 2 cases of perineal groove to increase awareness of this unusual malformation. Understanding that a perineal groove as a minor perineal anomaly will help avoid misdiagnosis and prevent extensive evaluations or unnecessary surgical procedures.
Corresponding Author: Lucia Diaz, MD, Department of Dermatology, The University of Texas Medical School at Houston, 6655 Travis St, Ste 600, Houston, TX 77030 (Lucia.firstname.lastname@example.org).
Published Online: September 11, 2013. doi:10.1001/jamadermatol.2013.4613.
Conflict of Interest Disclosures: None reported.
Diaz L, Levy ML, Kalajian A, Metry D. Perineal GrooveA Report of 2 Cases. JAMA Dermatol. 2014;150(1):101-102. doi:10.1001/jamadermatol.2013.4613