Necrotizing fasciitis is an illness that ascends quickly and affects the fascia, subcutaneous tissues, and deeper skin layers. To combat this infection, strong antibiotics are used along with prompt debridement. Frequent usage of such drugs is connected to antibiotic-associated diarrhea and colonic illnesses like colitis. High-spectrum antibiotic usage over an extended period of time can alter the gut microbiota, which promotes the growth of commensal bacteria including Staphylococcus aureus and Clostridioides difficile (previously known as Clostridium difficile) resulting in complications such as toxic megacolon. C. difficile infection can result in extreme inflammation and colon dilatation leading to toxic megacolon. In order to effectively treat necrotizing fasciitis, a timely diagnosis and vigorous management are essential; failing of which may have fatal consequences such as sepsis and even mortality. We present a case of a 56-year-old male, suffering from necrotizing fasciitis of the left lower limb which further complicated to toxic megacolon and caused mortality of the patient. Timely presentation and early diagnosis can be helpful in better prognosis, which in the context of this case was delayed; had the patient presented to the hospital earlier, there were chances of preventing mortality.

BACKGROUND: Clostridioides difficile (C. difficile) is the major pathogen causing antibiotic-associated diarrhea. There are a variety of symptoms associated with C. difficile infection (CDI) in adults, including self-limiting diarrhea, pseudomembranous colitis, toxic megacolon, septic shock, and even death from the infection. However, the infant\'s intestine appears to be completely resistant to the effects of C. difficile toxins A and B with rare development of clinical symptoms.
METHODS: In this study, we reported a 1-month-old girl with CDI who was born with neonatal hypoglycemia and necrotizing enterocolitis. Her symptom of diarrhea occurred after extensive use of broad-spectrum antibiotics during hospitalization and was accompanied by elevated white blood cell, platelet, and C-reactive protein levels, and repeated routine stool examinations were abnormal. She was recovered by norvancomycin (an analogue of vancomycin) and probiotic treatment. The results of 16 S rRNA gene sequencing also demonstrated the recovery of intestinal microbiota with the enrichment of Firmicutes and Lactobacillus.
CONCLUSIONS: Based on the literature review and this case report, clinicians should also pay attention to diarrhea caused by C. difficile in infants and young children. More strong evidence is needed to explain the true prevalence of CDI in this population and to better understand the C. difficile-associated diarrhea in infants.

Using an ambidirectional case-control study, we found that the odds of Clostridioides difficile infection (CDI) were 3.38 (P = .01) times higher for patients with multidrug-resistant organism (MDRO) colonization compared to those without. MDRO colonization or infection 1-12 months before CDI testing significantly increased risk of positive CDI diagnosis (odds ratio 4.71, P = .02 and odds ratio = 5.03, P = .05, respectively) independent of antibiotic use, age, and comorbidity status. MDRO colonization and infection are associated with CDI, most significantly if they precede CDI.

Nowadays, Klebsiella oxytoca is described as a causative organism for antibiotic-associated hemorrhagic colitis (AAHC). Here we report two cases of pediatric AAHC, from which K. oxytoca was cultured after starting amoxicillin-clavulanate or amoxicillin treatment. The patients developed severe abdominal pain and a large amount of bloody diarrhea. K. oxytoca was obtained in intestinal fluid culture of a boy through the colonoscopy. On the other hand, colonic tissue culture and intestinal fluid culture were negative of the other patient. K. oxytoca was detected in stool culture when he was admitted. These cases showed characteristic endoscopic findings of segmental hemorrhagic colitis, and both boys recovered spontaneously within 2-3 days after they stopped taking the antibiotics. Therefore, in children who develop relatively large amount of bloody diarrhea after antibiotic treatment, we should consider AAHC caused by K. oxytoca.