Cloacibacillus sp., a Potential Human Pathogen Associated with Bacteremia in Quebec and New Brunswick.

Bacteremia due to Cloacibacillus species is poorly described. We present three cases involving either Cloacibacillus evryensis or Cloacibacillus porcorum. The isolates were identified by 16S rRNA gene sequencing and were susceptible to antibiotics commonly used for anaerobic infections. The clinical significance of these organisms as potential emerging pathogens is discussed.

Surviving the sex trade: a comparison of HIV risk behaviours among street-involved women in two Canadian cities who inject drugs.

In Canada, very little is known about the factors and processes that cause drug-related harm among female intravenous drug users (IDUs). Women who inject drugs and participate in the survival sex trade are considered to be at increased risk for sexual and drug-related harms, including HIV infection. Between September 1999 and September 2000, women participating in the VIDUS cohort in Vancouver and the St. Luc Cohort in Montreal completed interviewer-administered questionnaires. Analyses were conducted to compare the demographic characteristics, sexual risk behaviours, risky injection practices and drug use patterns among women who self-identified as participating in the sex trade with those who did not identify as participating in the sex trade. Logistic regression was used to identify factors independently associated with exchanging sex for money or drugs. HIV prevalence at the study visit (September 1999-2000) was 29% for sex trade workers and 29.2% for non-sex trade workers. While patterns of sexual risk were similar, the risky injection practice and drug use patterns between sex trade workers and non-sex trade workers were markedly different. Logistic regression analysis of cross-sectional data revealed that independent behaviours associated with the sex trade included: greater than once per day use of heroin (adjusted OR 2.7), smokeable crack cocaine (adjusted OR = 3.3) and borrowing used syringes (adjusted OR = 2.0). Creative, client-driven interventions are urgently needed for women who trade sex for money or for drugs.

Sex-specific determinants of HIV infection among injection drug users in Montreal.

BACKGROUND: Sex-specific issues have not been extensively addressed in studies of HIV prevalence, despite the strong implications of differences between men and women in the risk of HIV transmission. The objective of this study was to examine sex-specific behaviours associated with HIV infection among injection drug users in Montreal. METHODS: A total of 2741 active drug users (2209 [80.6%] men) were recruited between 1988 and 1998. Information was sought on sociodemographic characteristics, drug-related behaviour and sexual behaviour, and participants were tested for HIV antibodies. Sex-specific independent predictors of HIV prevalence were assessed by stepwise logistic regression. RESULTS: The overall prevalence of HIV among study subjects was 11.1%; the prevalence was 12.0% among men and 7.5% among women. In multivariate models, a history of sharing syringes with a known seropositive partner (odds ratio [OR] for men 2.44, 95% confidence interval [CI] 1.72-3.46; OR for women 3.03, 95% CI 1.29-7.13) and of sharing syringes in the past 6 months (OR for men 0.61, 95% CI 0.44-0.85; OR for women 0.32, 95% CI 0.14-0.73) were independently associated with HIV infection. Other variables associated with HIV infection were homosexual or bisexual orientation, cocaine rather than heroin as drug of choice, frequency of injection drug use, and obtaining needles at a pharmacy or through needle exchange programs (for men only) and obtaining needles at shooting galleries and being out of treatment (for women only). INTERPRETATION: These results support the hypothesis that risk factors for HIV seropositivity differ between men and women. These sex-related differences should be taken into account in the development of preventive and clinical interventions.

Surveillance of invasive Streptococcus pneumoniae infection in the province of Quebec, Canada, from 1996 to 1998: serotype distribution, Antimicrobial susceptibility, and clinical characteristics.

In the province of Quebec, Canada, from 1996 to 1998, 3,650 invasive Streptococcus pneumoniae infections were reported. A total of 1,354 isolates were serotyped and tested for antimicrobial susceptibility. The distribution of serotypes remained stable over the 3 years, with serotypes 14, 6B, 4, 9V, 23F, and 19F accounting for 61% of the isolates. Overall, 90% of isolates were included in the current 23-valent vaccine and 67% were included in the 7-valent conjugate vaccine. We were able to determine that resistance to penicillin and to other antibiotics is increasing.

Risk behaviour change and HIV infection among injection drug users in Montreal.

OBJECTIVE: To investigate the independent association between changes in risk behaviour and HIV seroconversion risk among Montreal injection drug users (IDU). DESIGN: A longitudinal study of risk behaviour change and the maintenance of low-risk practices. At baseline and semi-annually, subjects were tested for HIV, and questionnaires on risk behaviour were completed. RESULTS: A total of 833 IDU were recruited from January 1992 to June 1998, and completed a minimum of three visits. Large fluctuations in risk behaviour were observed, and the risk of HIV infection appeared to be dependent upon the consistency of risk behaviour practised. IDU who consistently engaged in risky behaviour were at high risk of HIV infection. IDU who attempted to practise low-risk behaviour but experienced relapses to risky behaviour were also at considerable risk of infection. IDU who managed to maintain low-risk practices were at minimal risk. Using Cox regression analysis, the hazard ratio (HR) of HIV seroconversion among IDU who consistently and inconsistently shared needles with an HIV-positive partner was 8.17 (95% CI 3.59-18.59) and 2.63 (95% CI 1.33-5.17), respectively, relative to non-needle sharers. Corresponding HIV incidence rates were 30.42 per 100 person-years (py) among consistent sharers, 13.78 per 100 py among inconsistent sharers and 2.51 per 100 py among non-sharers. CONCLUSION: Although some HIV risk reduction was evident, behaviour change seems to be effective only in IDU who adopt and maintain low-risk practices. Additional strategies may be needed to assist IDU in the maintenance of low-risk practices.

Trends in antimicrobial resistance among clinical isolates of the Bacteroides fragilis group from 1992 to 1997 in Montreal, Canada.

The objective of the present study was to analyze the susceptibility profiles of 911 clinical strains of the Bacteroides fragilis group isolated from 1992 to 1997 in our institution in order to monitor susceptibility changes over time. Whereas the rates of resistance to metronidazole, imipenem, piperacillin-tazobactam, ticarcillin-clavulanic acid, penicillin, piperacillin, and cefoxitin remained essentially unchanged, there was a significant increase in the rates of resistance to clindamycin, which rose from 8.2% in 1992 to 19.7% in 1997 (P < 0.0004).

Update on Pan-American activities in the field of anaerobes: Canada.

During the past 15 years, important contributions have been made to the field of anaerobes in Canada. Studies on the importance of the intestinal flora as a source of vitamin K for humans, investigations of the mechanisms of synergy in polymicrobial infections, and extensive research on the field of immunocompetence of surgical patients have provided interesting and valuable information. Several clinical and epidemiological studies of anaerobic infections have been carried out. Rapid methods have been developed for the identification and susceptibility testing of clinical isolates. National and regional surveys have been conducted on the susceptibility patterns of the Bacteroides fragilis group. Studies on the mechanism of action of metronidazole and on the mechanisms of resistance of Bacteroides species have also been carried out. The Canadian Infectious. Disease Society has published position papers on therapy with cefotetan, ceftizoxime, and imipenem and on antimicrobial prophylaxis in surgical patients.

Clindamycin resistance in the Bacteroides fragilis group: association with hospital-acquired infections.

A retrospective study was conducted to assess the relationships between clindamycin resistance in members of the Bacteroides fragilis group, previous antimicrobial therapy, and the context for the development of infection, whether in the community or during hospitalization. Eighty-five clindamycin-resistant clinical strains (one isolate per patient) isolated from January 1988 to October 1994 were matched (one to one) with clindamycin-susceptible isolates recovered during the same period, and the charts of the patients from whom the isolates were recovered were reviewed retrospectively. Of the clindamycin-resistant strains, 65% were recovered from patients with hospital-acquired infections compared with 40% of the clindamycin-susceptible strains (odds ratio [OR], 2.75; 95% confidence interval [CI], 1.41-5.38; P = .002). Prior antimicrobial therapy for > or = 48 hours was also associated with clindamycin resistance (OR, 2.33; 95% CI, 1.16-4.70; P = .02). However, clindamycin resistance remained associated with hospital-acquired infections independent of prior antimicrobial therapy (Mantel-Haenszel weighted average OR, 2.22; 95% CI, 1.03-4.89; P = .04). Clinicians should consider the risks for clindamycin resistance when treating hospital-acquired infections caused by members of the B. fragilis group.

High rates of HIV infection among injection drug users participating in needle exchange programs in Montreal: results of a cohort study.

Needle exchange programs (NEPs) are designed to prevent human immunodeficiency virus (HIV) transmission among injection drug users. Although most studies report beneficial effects in terms of behavior modification, a direct assessment of the effectiveness of NEPs in preventing HIV infection has been lacking. A cohort study was conducted to assess the association between risk behaviors and HIV seroprevalence and seroincidence among injection drug users in Montreal, Canada. The association between NEP use and HIV infection was examined in three risk assessment scenarios using intensive covariate adjustment for empirical confounders: a cross-sectional analysis of NEP use at entry as a determinant of seroprevalence, a cohort analysis of NEP use at entry as a predictor of subsequent seroconversion, and a nested case-control analysis of NEP participation during follow-up as a predictor of seroconversion. From September 1988 to January 1995, 1,599 subjects were enrolled with a baseline seroprevalence of 10.7%. The mean follow-up period was 21.7 months. The adjusted odds ratio for HIV seroprevalence in injection drug users reporting recent NEP use was 2.2 (95% confidence interval 1.5-3.2). In the cohort study, there were 89 incident cases of HIV infection with a cumulative probability of HIV seroconversion of 33% for NEP users and 13% for nonusers (p < 0.0001). In the nested case-control study, consistent NEP use was associated with HIV seroconversion during follow-up (odds ratio = 10.5, 95% confidence interval 2.7-41.0). Risk elevations for HIV infection associated with NEP attendance were substantial and consistent in all three risk assessment scenarios in our cohort of injection drug users, despite extensive adjustment for confounders. In summary, in Montreal, NEP users appear to have higher seroconversion rates then NEP nonusers.

Serogroup-specific epidemiology of Streptococcus pneumoniae: associations with age, sex, and geography in 7,000 episodes of invasive disease.

A study sample of 7,010 episodes of invasive Streptococcus pneumoniae disease was obtained by combining 13 existing datasets. Disease episodes due to each of 12 pneumococcal serogroups (1, 3-9, 14, 18, 19, and 23) were then compared with episodes in a constant internal control group to describe serogroup-specific variations in disease frequency by age, sex, and geographic origin. The results are presented as odds ratios (with 95% confidence intervals) derived by logistic regression, with adjustment for the major confounders, including dataset of origin. Variation in the male:female ratios between serogroups is small, suggesting that capsular characteristics are an unlikely explanation for the male preference of S. pneumoniae. Serogroups associated with higher nasopharyngeal prevalence (e.g., 19 and 24) are relatively more common in Europe and North American, while the invasive serotypes 1 and 5 are much more common in South America. The custom of reporting serogroup frequencies in two age groups, children and adults, conceals much of the variation in the age distributions across the whole span of life. The reduction of risk associated with serogroups 6, 14, 18, 19, and 23 beyond childhood follows different gradients, being most abrupt in serogroups 14 and most gradual in serogroup 18. The relative risk of disease with serotype 1 declines steadily throughout life, while with serotypes 3 and 8 it increases over middle age. Serogroups 7 and 23 are found unusually frequently in the third decade of life. Because of the wide differences in the epidemiology of individual serogroups of S. pneumoniae, it is questionable whether pneumococcal infection should continue to be classified as a single disease entity.

Clinical usefulness of intravenous human immunoglobulins in invasive group A Streptococcal infections: case report and review.

The spectrum of invasive Streptococcus pyogenes (group A streptococcus) infections includes bacteremia, toxic shock syndrome, and necrotizing fasciitis or myositis. We report the successful use of intravenous immunoglobulins in conjunction with antibiotics and surgery in a case of necrotizing myositis, toxic shock, and bacteremia. A literature review revealed that three other patients with invasive group A streptococcal infections had been treated with immunoglobulins: one adult patient had toxic shock syndrome, one had necrotizing fasciitis, and one child had septic arthritis. On the basis of this report and the review, we suggest that intravenous immunoglobulins may be useful in the treatment of all forms of invasive group A streptococcal infections associated with toxic shock syndrome.

Hepatitis B, C, and D virus infections in patients with chronic hepatitis, cirrhosis, and hepatocellular carcinoma: a comparative study in Niger.

Eighty-nine Sahelian African patients with chronic active hepatitis (CAH) (14), cirrhosis (49), hepatocellular carcinoma (HCC) (26), and 47 controls were tested for hepatitis B virus (HBV, hepatitis B surface antigen [HBsAg]) and hepatitis D virus (HDV, anti-HDV antibody). Seventy-three percent of the patients were positive for HBsAg versus 29.8% of the controls (P < 0.0001). With anti-HDV test, 55.0% of the patients were positive versus 17.0% of the controls (P < 0.0001). To assess the prevalence of antibody to hepatitis C virus (HCV), we used an enzyme-linked immunosorbent assay for screening (anti-HCV2): 19.1% of the patients were positive versus 6.4% of the controls (P < 0.05). An association between HBsAg and anti-HDV-positive test results was found in 46.1% of the patients versus 6.4% of the controls (P < 0.0001). A combination of HBsAg and anti-HCV2-positive test results was found in 13.5% of the patients versus 2.2% of the controls (P < 0.05). Anti-HDV and anti-HCV2 test results were positive in 13.5% of the patients versus 2.2% of the controls (P < 0.05). Triple-positive test results (HBsAg, anti-HDV, and anti-HCV2) were found in 11.2% of the patients but in none of the controls (P < 0.025). Triple-negative test results were found in 14.6% of the patients versus 57.4% of the controls (P < 0.0001). The predominant association of the chronic HBV infection with CAH, cirrhosis, and HCC is confirmed in Sahelian Africa. The HDV superinfection (chronic HBV plus HDV infections) may be a major etiology.(ABSTRACT TRUNCATED AT 250 WORDS)

Longitudinal study of susceptibilities of species of the Bacteroides fragilis group to five antimicrobial agents in three medical centers.

A total of 579 clinical isolates of the Bacteroides fragilis group collected from three Canadian hospitals were tested for susceptibility to five antimicrobial agents by using an agar dilution method. During the 4-year survey, isolates from intra-abdominal infections were collected from the following sites: abdominal abscesses (48%), peritoneal fluid (39%), blood (10%), and bile (3%). B. fragilis was the most prevalent species (35.4%), followed by B. thetaiotaomicron (19.2%), B. ovatus (15.9%), and B. vulgatus (11%). No metronidazole- or imipenem-resistant strains were found during the survey. Resistance profiles varied among the different species tested: 7.8, 2.9, and 7.3% of B. fragilis strains (n = 205) and 68.1, 17.2, and 9.4% of non-B. fragilis strains (n = 373) were resistant to cefotetan, cefoxitin, and clindamycin, respectively. B. fragilis and B. vulgatus demonstrated lower resistance rates than B. thetaiotaomicron, B. ovatus, B. distasonis, and B. caccae. During the study, rates of resistance to cefotetan and clindamycin fluctuated but rates of resistance to cefoxitin increased, particularly at one center. These data indicate a need to determine the susceptibility patterns of the B. fragilis group periodically at each hospital.

Illicit use of methadone among i.v. drug users in Montreal.

Few studies have been done on the prevalence of illicit methadone use. Five hundred fifty-nine IV drug users recruited in various ways in Montreal were interviewed concerning their drug use as part of a longitudinal study on HIV infection. Of this number, 133 had heroin as their drug of preference and 426 cocaine. Among the cocaine group, 202 also used heroin. The lifetime prevalence of any illicit methadone use was 59.4% in the heroin group, 26.7% in the cocaine/heroin group, and 3.6% in the cocaine-only group. The 6-month (preceding the interview) prevalence of any illicit use was 42.1%, 6.9%, and 1.3%, respectively, and the prevalence of at least weekly illicit use during that period was 6.3%, 2.0%, and 0%, respectively. The prevalence of illicit methadone use is significant in the population studied. Whether this level of use will be affected by more stringent control on methadone prescription and dispensation remains to be demonstrated.

Seroprevalence of and risk factors for HIV-1 infection in injection drug users in Montreal and Toronto: a collaborative study.

OBJECTIVE: To determine the prevalence of antibodies to HIV-1 and risk factors for HIV-1 infection among injection drug users. DESIGN: Questionnaire survey. A venous blood sample was taken for HIV-1 antibody testing. SETTING: Montreal and Toronto. PARTICIPANTS: A total of 810 subjects who had used injection drugs in the previous 6 months recruited mainly from treatment centres and from the street in Montreal (425 subjects) and from treatment centres in Toronto (385 subjects) between September 1988 and September 1990. The overall participation rate was 82%. OUTCOME MEASURES: HIV-1 seropositivity, sociodemographic and behavioural risk factors for HIV-1 infection. RESULTS: The overall seroprevalence rate of HIV-1 infection was 4.8% (95% confidence limits [CL] 3.5 and 6.5). In Montreal the rate was 8.2% (95% CL 6.0 and 11.2), and in Toronto 1.0% (95% CL 0.4 and 2.6) (p < 0.001). Seropositive subjects were significantly older (p = 0.041) and were more likely to have a history of imprisonment (p = 0.006) than seronegative subjects. In univariate analysis seropositivity was associated with the following behaviours: more frequent cocaine use (p < 0.001), injecting drugs in "shooting galleries" (p = 0.002), sharing equipment with a person known to be HIV-1 seropositive (p = 0.006), "booting" fresh blood (p = 0.004), homosexual or bisexual orientation (p = 0.006), engaging in prostitution (p < 0.001) and, for men, number of male sexual partners in the previous 6 months (p = 0.007). In multivariate analysis the determinants of HIV-1 seropositivity were Montreal as the city of recruitment (odds ratio [OR] 6.7, 95% CL 2.32 and 19.42), engaging in prostitution (OR 2.13, 95% CL 1.01 and 4.75), a history of imprisonment (OR 3.51, 95% CL 1.33 and 9.29) and sharing equipment with a person known to be HIV-1 seropositive (OR 4.43, 95% CL 1.43 and 13.74). CONCLUSIONS: Our findings show that HIV-1 is circulating among injection drug users in Montreal and Toronto and that both drug use and sexual behaviours are implicated in the transmission of infection in the populations studied. Adapted preventive programs should be developed to prevent further spread of HIV-1 infection in this population.

Susceptibilities of beta-lactamase-positive and -negative strains of Campylobacter coli to beta-lactam agents.

The percentages of susceptibility of 28 strains of Campylobacter coli to beta-lactam agents were 96% for amoxicillin and ampicillin, 57% for ticarcillin, 4% for cefoxitin and cefuroxime, 61% for cefotaxime, and 11% for ceftazidime. None of the strains were susceptible to penicillin G, piperacillin, cefazolin, cephalothin, cefamandole, and cefoperazone. All strains were susceptible to imipenem and ciprofloxacin, and 21% were susceptible to erythromycin. A beta-lactamase was detected in 68% of the strains by cefinase disks and by the nitrocefin method. The beta-lactamase-positive strains were significantly less susceptible to amoxicillin, ampicillin, and ticarcillin than the beta-lactamase-negative strains (P < or = 0.003). Clavulanic acid (0.25 microgram/ml) but not sulbactam and tazobactam (2 micrograms/ml) lowered to susceptible levels the amoxicillin and ampicillin MICs of the only strain of C. coli resistant to amoxicillin, ampicillin, and ticarcillin.