Risk factors for intolerance of oral 5-aminosalicylic acid preparations in pediatric ulcerative colitis.

BACKGROUND: No previous study of Japanese children with ulcerative colitis (UC) has reported the risk factors for intolerance of 5-aminosalicylic acid (5-ASA). We aimed to identify risk factors for intolerance of oral 5-ASA preparations in pediatric UC. METHODS: Patients with childhood-onset UC who were seen at our hospital between November 2003 and March 2020 were investigated. Intolerance of 5-ASA was defined as having clinical symptoms (pyrexia, abdominal pain, diarrhea, bloody stool) that worsened after starting oral administration of 5-ASA and improved after discontinuation of 5-ASA. Patient sex, age, body size, laboratory data, pediatric UC activity index scores, and colonoscopy-based determinations of the extent and severity of the affected lesion at initiation of 5-ASA of intolerant and tolerant groups were compared. RESULTS: Fifteen patients were in the intolerant group, and 37 were in the tolerant group. The leukocyte count, C-reactive protein level, and erythrocyte sedimentation rate were significantly higher in the intolerant group than the tolerant group; the albumin level in the intolerant group was significantly lower. All intolerant patients and 68% of tolerant patients had pancolitis (Paris classification E4). Patients with a large, affected area (Paris classifications E3 and E4) more frequently had intolerance to 5-ASA than patients with a small lesion. The cumulative Mayo endoscopic subscore (cMES), which is the sum of MES scores for six regions of the large intestine, was significantly higher in the intolerant group. CONCLUSIONS: Pediatric UC patients with more intense inflammation and a large lesion could have an increased risk of intolerance for 5-ASA.

Analysis of Haemophilus influenzae serotype f isolated from three Japanese children with invasive H. influenzae infection.

In Japan, publicly subsidized Haemophilus influenzae serotype b vaccines became available in 2011; consequently, the incidence of invasive H. influenzae infection in paediatric patients of less than 5 years of age decreased dramatically. In 2013, the first case of H. influenzae serotype f (Hif) meningitis in a Japanese infant was reported, and another case of Hif meningitis in a Japanese infant was observed in 2013. We experienced a fatal paediatric case of Hif bacteraemia in 2004; therefore, we conducted an analysis of the three Hif strains isolated from these three Japanese children with invasive Hif infections. All three strains were ß-lactamase-non-producing, ampicillin-sensitive strains, with MICs of 1 µg ml(-1) or less. However, one of the three strains showed slightly elevated MICs for ampicillin (1 µg ml(-1)), cefotaxime (0.25 µg ml(-1)) and meropenem (0.13 µg ml(-1)). A molecular analysis by multilocus sequence typing identified all three strains as sequence type (ST) 124, which is a predominant invasive Hif strain in many countries. SmaI-digested PFGE showed variable DNA fragmentation patterns among the strains, suggesting that some highly virulent strains have originated from a single ST124 clone and caused invasive Hif infections in Japan. Additional studies are needed to determine the factors that have led to the clonal expansion of virulent ST124 strains.