Escherichia coli O121:H19 infection identified on microagglutination assay and PCR.

Non-O157 Shiga toxin-producing Escherichia coli (STEC) strains are increasingly recognized as foodborne pathogens that trigger hemolytic uremic syndrome (HUS). The detection and isolation of these strains is important, but distinguishing their bacteriological profiles is difficult. A 2-year-old girl developed HUS with mild renal involvement 22 days after consuming barbecued meat. Clinical and laboratory findings gradually improved without specific treatment. Because neither enterohemorrhagic E. coli (EHEC) nor Shiga toxins were detected in stool cultures in a clinical laboratory and the patient tested negative for circulating antibodies to O157 lipopolysaccharide, the case was initially diagnosed as probable atypical HUS. Subsequent serodiagnostic microagglutination assay and polymerase chain reaction-based molecular testing, however, indicated the presence of the EHEC O121:H19 strain with stx2. Thus, to correctly diagnose and treat HUS, a system for detecting non-O157 STEC in a clinical setting is urgently needed.

Initial intravenous immunoglobulin therapy without aspirin for acute Kawasaki disease: a retrospective cohort study with a Bayesian inference.

OBJECTIVE: To clarify the necessity of acetylsalicylic acid (ASA) administration combined with intravenous immunoglobulin (IVIG) therapy in the treatment of acute Kawasaki disease. DESIGN: Retrospective cohort study. SETTING: Multicentre. PARTICIPANTS: This study included 735 patients with Kawasaki disease aged ≤10 years and hospitalised between 4 and 10 days of illness in eight Japanese hospitals from January 2016 to December 2020. EXPOSURES: High-dose (HD) ASA was administered with initial IVIG to 333 patients in 6 hospitals (HD group). ASA was not administered routinely to 402 patients in the other two hospitals, and low-dose ASA was only administered when patients developed coronary artery lesions or pericardial effusion (non-HD group). PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the presence of coronary artery lesions, defined as a coronary artery diameter >+2.5 SD of body surface area within 1 month of onset. The secondary outcome was responsiveness to the initial IVIG therapy. Adjusted risk ratios for the outcomes were calculated using modified Poisson regression models. Bayesian analysis was conducted to estimate the posterior probability of the treatment effect of HD ASA under several prior distributions. RESULTS: The incidence of coronary artery lesions was not significantly higher in the HD group than in the non-HD group (12/333 (3.6%) vs 15/402 (4.0%)). The proportion of non-responders to initial IVIG was similar between the two groups (HD group: 78/333 (23%); non-HD group: 83/402 (22%)). In the Bayesian analysis, considering a difference of ≤2% to be of no clinical importance, there was only a 9.3% chance of reduced risk of coronary artery lesions in the HD group compared with the non-HD group even with a strongly enthusiastic prior for HD treatment. CONCLUSIONS: Compared with HD ASA treatment, treatment without ASA in the acute phase of Kawasaki disease was not associated with increased complications from Kawasaki disease.

Enantioselective synthesis of (S)-2-cyano-2-methylpentanoic acid by nitrilase.

The nitrilase gene of Rhodococcus rhodochrous J1 was expressed in Escherichia coli using the expression vector, pKK223-3. The recombinant E. coli JM109 cells hydrolyzed enantioselectively 2-methyl-2-propylmalononitrile to form (S)-2-cyano-2-methylpentanoic acid (CMPA) with 96 % e.e. Under optimized conditions, 80 g (S)-CMPA l(-1) was produced with a molar yield of 97 % at 30 °C after a 24 h without any by-products.