Gilles Delage

Randomized, controlled trial of antibiotic therapy for Escherichia coli O157:H7 enteritis.

We undertook a prospective, controlled study to evaluate the effect of trimethoprim-sulfamethoxazole in children with proven Escherichia coli O157:H7 enteritis on the duration fo symptoms, on fecal excretion of pathogen, and on the risk of progression to hemolytic-uremic syndrome. There was no statistically significant effect of treatment on progression of symptoms, fecal pathogen excretion, or the incidence of HUS (2/22 vs 4/25; p = 0.67). Our results suggest that a multicentric trial using rapid diagnostic methods to permit early randomization should be carried out.

Epidemiological Features of Pertussis in Hospitalized Patients in Canada, 1991- 1997: Report of the Immunization Monitoring Program—Active (IMPACT)

To assess the morbidity associated with the continued high levels of pertussis, we studied all children <2 years of age who were admitted to the 11 Immunization Monitoring Program--Active (IMPACT) centers, which constitute 85% of Canadas tertiary care pediatric beds. In the 7 years preceding implementation of acellular pertussis vaccine, a total of 1,082 pertussis cases were reported, of which 49.1% were culture-confirmed. The median age of the patients was 12.4 weeks; 78.9% of cases were in children <6 months of age. Complications of pertussis were common: pneumonia was reported in 9.4% of cases, new seizures in 2.3%, and encephalopathy in 0.5%. There were 10 deaths (0.9%), all in children < or =6 months of age. Duration of hospitalization was longer (9.3 days vs. 4.9 days; P = .001) and intensive care was required more frequently (19.2% vs. 4.9%; P = .001) in infants under <6 months of age than in those > or =6 months. Pertussis continues to cause significant morbidity and occasional mortality in Canada, particularly in young infants.

Giant-cell pneumonia caused by parainfluenza virus.

IN 1959, Enders and collaborators I isolated measles virus from the lungs of patients dying of giant cell pneumonia. Since then, this virus has been firmly established as a causative agent of this disease in patients with leukemia ~ or immunodeficiency diseases? A recent pathology textbook describes measles virus as the sole agent responsible for giant cell pneumonia/ We describe two patients with a severe combined immunodeficiency syndrome in whom we found giant cell pneumonia caused by a parainfiuenza type 3 virus. CASE REPORTS

Performance of a multiplex PCR for the determination of Haemophilus influenzae capsular types in the clinical microbiology laboratory

To improve tools for the surveillance of invasive H. influenzae in the context of the drastic decrease of type b infections following the implementation of vaccination, a two-step PCR technique was developed to detect the capsule and type specific regions of H. influenzae. The technique of Falla et al (1994) was modified to amplify in a first step the capsule and type b regions by multiplex PCR. For non-b capsulated strains, the type a, c, d, e, and f loci were afterward detected simultaneously by an optimized touch-down PCR technique. An internal control of extraction and amplification (16S rDNA) was included for both PCR techniques. Overall, this technique was shown to perform as efficiently or better than the slide agglutination without risks of interpretation errors. Of the 138 H. influenzae strains tested, seven that had given doubtful results by the agglutination technique were unequivocally typed by PCR.

Rotavirus vaccine withdrawal in the United States: The role of postmarketing surveillance

On August 31, 1998, Rotashield (Wyeth Laboratories, Marietta, Pennsylvania) was licensed by the United States Food and Drug Administration for oral administration to infants at two, four and six months of age in the United States. This product is a live, attenuated rhesus rotavirusbased tetravalent vaccine (RRV-TV). Each dose of vaccine contains 1×10 plaque forming units of each of four strains: one is a rhesus rotavirus strain with human serotype 3 specificity, and the three other strains are single gene human-rhesus reassortants that contain the human gene for serotype 1, 2 and 4 antigens, respectively, along with other genes from the parent rhesus rotavirus strain. Shortly following licensure of the vaccine in the United States, the Advisory Committee on Immunization Practices (ACIP) (1) recommended routine immunization with three oral doses of RRV-TV for infants at age two, four and six months of age for the prevention of rotavirus disease in the United States. The rationale for recommending use of the vaccine was the following.

A Family Cluster of Chagas Disease Detected through Selective Screening of Blood Donors: A Case Report and Brief Review

Chagas disease is rare in Canada, and is most frequently observed among individuals who have resided in Latin America. The disease can enter a prolonged asymptomatic phase during which infected individuals do not experience symptoms, thus hindering its diagnosis – particularly in nonendemic regions such as Canada. This article describes a cluster of cases of Chagas disease among a single family, which was discovered on screening after two affected members of the family donated blood. The current state of screening programs for Trypanosoma cruzi are discussed, and suggestions for future directions are included.

Immune response to verotoxin 1 and 2 in children with Escherichia coli O157:H7 hemorrhagic colitis and classic hemolytic uremic syndrome.

OBJECTIVES To compare neutralizing antibody titres against verotoxin (vt)-1 and vt-2 between children with uncomplicated hemorrhagic colitis (hc) and those with classic hemolytic uremic syndrome (hus). vt antibody titres were also compared in children with hc who received trimethoprim-sulfamethoxazole with those who did not. DESIGN Prospective study. SETTING Tertiary pediatric hospital. POPULATION STUDIED Children with hc (n=41) or classic hus (n=12). INTERVENTIONS Serum antibodies against vt-1 and vt-2 were determined by quantitative neutralization. MAIN RESULTS Antibodies were detected in 40% (21 of 53) of serum samples for vt-1 and in 100% (53 of 53) of samples for vt-2. A positive immune response, defined as a fourfold increase in vt antibody titres or as a single titre of 1/64 or greater, was found in 0% (0 of 12) of patients with hus compared with 7% (three of 41) of those with hc for vt-1 (P=0.4); and in 17% (two of 12) of patients with hus compared with 22% (nine of 41) of those with hc for vt-2 (P=0.3). The rate of seroconversion against either vt-1 or vt-2 was comparable in treated and untreated patients with uncomplicated hc. CONCLUSIONS There was no evidence that neutralizing antibody levels against vt-1 or vt-2 in classic hus or after antibiotic therapy are substantially different from those in patients with uncomplicated hc.

Meningitis and Brain Abscess Due to Clostridium Perfringens And Clostridium Paraputrificum Following Orbital Trauma

An 8 year old boy developed cerebral abscess and purulent meningitis due to Clostridium perfringens and Clostridium paraputrificum after trauma to the left orbit. The patient made a satisfactory recovery with surgical treatment and antibiotic therapy. A review of the literature revealed that meningitis due to Clostridia is rare and usually related to penetrating trauma, and that penetrating trauma to the orbit is associated with significant central nervous system morbidity.