Necrotising fasciitis with extensive necrosis caused by Lactobacillus: A case report

Abstract

Background Necrotising fasciitis (NF) is a life-threatening soft-tissue infection that rapidly destroys the epidermis, subcutaneous tissue, and fascia. Despite their low virulence, Lactobacillus spp. can cause NF, and because of its rare incidence, there is limited knowledge about its molecular and clinicopathological characteristics. We report a rare case of NF in a patient with undiagnosed diabetes mellitus and severe obesity due to infection with two types of Lactobacillus spp. that manifested in extensive necrosis. Case presentation A 48-year-old woman was referred to our hospital with a complaint of difficulty in walking due to severe bilateral thigh pain. She presented with pale redness, swelling, and severe skin pain extending from the pubic region to the groin. The patient was morbidly obese, had renal dysfunction and had not been diagnosed having diabetes mellitus; her LRINEC (Laboratory Risk Indicator for Necrotising Fasciitis) score was 9, indicating a high risk of NF. An exploratory surgical incision was made and NF was diagnosed based on fascial necrosis. Emergent surgical debridement was performed, and cultures of the wound and abscess revealed two types of Lactobacillus spp.: Lactobacillus salivariusand L. iners. The patient was admitted to the intensive care unit (ICU), where antibiotics were administered and respiratory and circulatory managements were performed. Diabetic ketoacidosis was detected, which was treated by controlling the blood glucose level stringently via intravenous insulin infusion. The patient underwent a second debridement on day 11 and, skin suture and skin grafting on day 36. The patient progressed well, was transferred from the ICU to the general ward on day 41, and was discharged unassisted on day 73. Conclusions Lactobacillus spp. are rarely pathogenic to healthy individuals and can seldom trigger NF. However, these bacteria can cause rare infections such as NF in immunocompromised individuals, such as those with diabetes and obesity, and an early diagnosis of NF is imperative; surgical intervention may be required for prevention of extensive necrosis. The LRNEC score may be useful for the early diagnosis of NF even for less pathogenic bacteria such as the Lactobacillus.