Extensive necrotizing fasciitis in an immunocompetent neonate leading to rectovulvar and rectovaginal fistulae: A case report.

Background: Necrotizing fasciitis (NF) is a rare but life-threatening soft tissue infection in neonates, associated with high morbidity and mortality. Perineal involvement in female neonates is particularly uncommon and may lead to devastating complications. Case presentation: A 5-week-old previously healthy female infant presented with a 10-day history of a generalized rash that later localized to the perianal region and limbs, developing into ulceration. The condition evolved into extensive perineal necrosis complicated by rectovulvar and rectovaginal fistulae. Initial clinical features were suggestive of eczema herpeticum with secondary bacterial infection, and empirical antiviral and broad-spectrum antibiotic therapy was initiated. HSV PCR was not performed, however, HSV-1/2 IgG levels were markedly elevated. Blood and peritoneal swab cultures were negative, while ulcer biopsy and wound swab cultures grew Conclusion: This case highlights that severe perineal necrotizing fasciitis can occur in immunocompetent neonates and may be complicated by rare rectovulvar and rectovaginal fistulae. Early recognition, multidisciplinary care, and timely fecal diversion are critical to achieving favorable outcomes, even in the absence of identifiable immunodeficiency.