Comprehensive validation of early diagnostic algorithms for myocardial infarction in the emergency department.

OBJECTIVE: To comprehensively evaluate diagnostic algorithms for myocardial infarction using a high-sensitivity cardiac troponin I (hs-cTnI) assay. PATIENTS AND METHODS: We prospectively enrolled patients with suspected myocardial infarction without ST-segment elevation from nine emergency departments in Japan. The diagnostic algorithms evaluated: (i) based on hs-cTnI alone, such as the European Society of Cardiology (ESC) 0/1-h or 0/2-h and High-STEACS pathways; or (ii) used medical history and physical findings, such as the ADAPT, EDACS, HEART, and GRACE pathways. We evaluated the negative predictive value (NPV), sensitivity as safety measures, and proportion of patients classified as low or high-risk as an efficiency measure for a primary outcome of type 1 myocardial infarction or cardiac death within 30 days. RESULTS: We included 437 patients, and the hs-cTnI was collected at 0 and 1 hours in 407 patients and at 0 and 2 hours in 394. The primary outcome occurred in 8.1% (33/407) and 6.9% (27/394) of patients, respectively. All the algorithms classified low-risk patients without missing those with the primary outcome, except for the GRACE pathway. The hs-cTnI-based algorithms classified more patients as low-risk: the ESC 0/1-h 45.7%; the ESC 0/2-h 50.5%; the High-STEACS pathway 68.5%, than those using history and physical findings (15-30%). The High-STEACS pathway ruled out more patients (20.5%) by hs-cTnI measurement at 0 hours than the ESC 0/1-h and 0/2-h algorithms (7.4%). CONCLUSIONS: The hs-cTnI algorithms, especially the High-STEACS pathway, had excellent safety performance for the early diagnosis of myocardial infarction and offered the greatest improvement in efficiency.

[Isolation of verotoxin-producing Escherichia coli from pediatric patients suffering from enteritis with bloody stool and intussusception].

We tried to isolate verotoxin-producing Escherichia coli (VTEC) on sorbitol-MacConkey (SMAC) agar and in part by the polymerase chain reaction (PCR) method from sporadic enteritis patients with bloody stools and intussusception patients who came to three pediatric clinics in the Fukuoka area from October 1990 to September 1994. VTEC O157:H7 strains were isolated from 6 (10.5%) of 57 patients with bloody stools, Campylobacter spp. 15 (26.3%), Salmonella spp. 14 (24.6%) and Yersinia enterocolitica 2. We were not able to detect VT genes by PCR from 11 of 20 patients from whose stools no causative bacteria were isolated. Massive fresh bloody stools following frequent watery diarrhea were typical of the VTEC enteritis patients. Only 1 patient had fever and 2 had leukocytosis, but the C-reactive protein in all of them was below 1+. The VTEC strains were isolated during the summer season, 1 in June, 2 in July, and 3 in September. Since in the area O157:H7 appeared to be the most prevalent VTEC serotype, SMAC is very useful for screening VTEC in bloody stools. VTEC seems to be a rare pathogen of intussusception because the organisms were detected from none of the 30 patients.

[A study for serodiagnosis of verotoxin-producing Escherichia coli (enterohemorrhagic E. coli) O157 by the bacterial agglutination technique].

We evaluated the usefulness of bacterial agglutination antibodies for serodiagnosis of verotoxin-producing Escherichia coli (enterohemorrhagic E. coli) O157 infections. We examined 50 serum samples from 50 control children (whiout diarrhea 31, with diarrhea 19), 24 samples from 8 diarrhea cases due to O157:H7, 37 samples from 14 cases of hemolytic uremic syndrome (HUS) for antibodies to heat-killed E. coli E32511 (O157:H.-) strain using the bacterial agglutination technique. Of the control sera all but one (x80) showed 20 > or = in the antibody. All the diarrhea patients due to O157:H7 showed a significant rise (x160-x5120) of the titers in the sera at 5-7 days on illness, after that the titers fell rapidly. Significant antibody rise (x160-x5120) was detected in twelve out of 14 HUS patients at the early stage of the illness which fell in the convalescent phase. The assay appeared to be a useful serodiagnostic technique because of its easiness and simplicity as well as because of its high sensitivity and specificity.

[Analysis of verotoxin-producing Escherichia coli (O157:H7) strains isolated in the Fukuoka area in 1994 by pulsed-field gel electrophoresis].

Nine verotoxin-producing Escherichia coli O157:H7 strains were isolated from 9 pediatric patients with sporadic enteritis between July and September 1994 at four clinics in the Fukuoka area. The patients included two families with two cases each. These strains were analyzed by pulsed-field gel electrophoresis for Xba I-digested DNA fragments. The restriction patterns were identical between each two strains within the two family outbreaks, but different among the seven strains of the distinct seven sporadic cases. It is strongly suggested that the seven sporadic cases were infected through distinct sources, and that the two family cases were due to a common source of infection or person to person infection.

Indirect hemagglutination assay for antibodies to Escherichia coli lipopolysaccharides O157, O111 and O26 in patients with hemolytic uremic syndrome.

We examined sera from 10 patients with hemolytic uremic syndrome (HUS) and 51 controls, with and without diarrhea, for antibodies to Escherichia coli lipopolysaccharides (LPS) O157, O111 and O26 using the indirect hemagglutination (IHA) assay. A significant rise (to a titer of > or = 2560) in IHA antibody to O157 LPS was detected in eight of the 10 HUS patients, to O111 in two patients, one of whom showed concomitantly an antibody rise to O157, but to O26 in no patients. The IHA titers fell rapidly after the acute phase of the illness. Of the control sera 15 (29.4%) non-specifically agglutinated uncoated sheep red blood cells (SRBC) at a titer of > or = 80, six (3.9%) at > or = 320 and the maximum was 640. In spite of the relatively low level of non-specific agglutination the IHA appeared to be a useful screening method to identify verotoxin-producing E. coli infections at the early stage of HUS because the titers were clearly higher than non-specific agglutination and the assay is easy to perform and gives results quickly. Artificial carriers are being considered for use in place of SRBC to diminish the non-specific hemagglutination.

Epidemiologic application of pulsed-field gel electrophoresis to an outbreak of Campylobacter fetus meningitis in a neonatal intensive care unit.

An outbreak of nosocomial Campylobacter fetus meningitis occurred in a neonatal intensive care unit (NICU). Eight C. fetus strains were isolated from 4 infants with meningitis, the mother of the index patient and 2 infants who were asymptomatic intestinal carriers. The pulsed-field gel electrophoresis (PFGE) pattern with the restriction endonucleases Smal and Sall were found to be identical for the nosocomial C. fetus isolates, but the patterns were different from those of sporadic strains. These nosocomial strains were strongly suspected to be a single strain. The finding revealed that the index patient was infected by the mother, and that the outbreak developed from this patient by cross-infection. This is the first confirmed nosocomial C. fetus meningitis outbreak spread by cross-infection in a NICU.