Susceptibilities to co-trimoxazole of pathogens isolated from blood and stool specimens in Abidjan, Ivory Coast, 1994 to 1996

Antimicrobial drug resistance among clinically relevant bacterial isolates in sub-Saharan Africa: a systematic review

BACKGROUND

Little is known about the prevalence of antimicrobial resistance (AMR) amongst bacterial pathogens in sub-Saharan Africa (sSA), despite calls for continent-wide surveillance to inform empirical treatment guidelines.

METHODS

We searched PubMed and additional databases for susceptibility data of key pathogens for surveillance, published between 1990 and 2013. Extracted data were standardized to a prevalence of resistance in populations of isolates and reported by clinical syndrome, microorganism, relevant antimicrobial drugs and region.

RESULTS

We identified 2005 publications, of which 190 were analysed. Studies predominantly originated from east sSA (61%), were hospital based (60%), were from an urban setting (73%) and reported on isolates from patients with a febrile illness (42%). Quality procedures for susceptibility testing were described in <50% of studies. Median prevalence (MP) of resistance to chloramphenicol in Enterobacteriaceae, isolated from patients with a febrile illness, ranged between 31.0% and 94.2%, whilst MP of resistance to third-generation cephalosporins ranged between 0.0% and 46.5%. MP of resistance to nalidixic acid in Salmonella enterica Typhi ranged between 15.4% and 43.2%. The limited number of studies providing prevalence data on AMR in Gram-positive pathogens or in pathogens isolated from patients with a respiratory tract infection, meningitis, urinary tract infection or hospital-acquired infection suggested high prevalence of resistance to chloramphenicol, trimethoprim/sulfamethoxazole and tetracycline and low prevalence to third-generation cephalosporins and fluoroquinolones.

CONCLUSIONS

Our results indicate high prevalence of AMR in clinical bacterial isolates to antimicrobial drugs commonly used in sSA. Enhanced approaches for AMR surveillance are needed to support empirical therapy in sSA.

Reducing mortality with cotrimoxazole preventive therapy at initiation of antiretroviral therapy in South Africa

OBJECTIVE

To assess the effectiveness of cotrimoxazole preventive therapy (CPT) among individuals with CD4 cell count above 200 cells/microl and varying WHO clinical stages in reducing mortality during combination antiretroviral therapy (cART).

DESIGN

A cohort study.

METHODS

Using proportional hazards modeling, we compared mortality during the first 12 months after cART initiation among patients receiving CPT with patients not receiving CPT. We adjusted for clinic level confounding throughout.

RESULTS

We included 14 097 patients starting cART between January 2003 and January 2008, 62% of whom were men, the median CD4 cell count was 132 cells/microl, and 1289 died (11%). The baseline median CD4 cell count was lower (118 vs. 153 cells/microl) among the 7508 patients who received CPT compared with the 6589 patients who did not. In adjusted multivariate modeling, stratifying for baseline CD4 cell count and WHO stage, CPT reduced mortality overall (hazard ratio 0.64, P < 0.001) and for all individuals with CD4 cell count below 200 cells/microl or WHO clinical stage 3 or 4 conditions but did not reduce mortality for patients with both CD4 cell count above 200 cells/microl and WHO clinical stage 1 or 2.

CONCLUSION

We demonstrated a 36% reduction in mortality extending to patients associated with CPT when used with cART that extended to patients with CD4 cell count above 350 cells/microl in a setting with minimal malaria and high rates of cotrimoxazole-resistant bacteria. This provides important additional data toward efforts to increase CPT provision among all cART initiators in resource limited settings.

Daily Trimethoprim-Sulfamethoxazole Prophylaxis Rapidly Induces Corresponding Resistance Among IntestinalEscherichia coliof HIV-Infected Adults in Kenya

Background. Trimethoprim-sulfamethoxazole (TMP-SMZ) has been recommended by World Health Organization (WHO) as daily prophylaxis for Africans with AIDS to prevent opportunistic infections. Daily TMP-SMZ may reduce its susceptibility to commensal intestinal Escherichia coli (E coli), increasing the burden of TMP-SMZ-resistant pathogens. Methods. Participants received either daily TMP-SMZ (CD4 <350 cells/mm3) or daily multivitamins (MVIs; CD4 ≥350 cells/mm3) for 6 months. Stool was collected at baseline, 2 weeks, 2 months, and 6 months. A random E coli was tested for susceptibility. Results. Baseline prevalence of TMP-SMZ resistance ranged from 71% to 81% and was not different across CD4 strata. At 2 weeks, prevalence of TMP-SMZ-resistant E coli increased significantly from 78% to 98% (P < .001) among persons taking daily TMP-SMZ and did not change among persons taking MVIs. Conclusions. Daily prophylaxis with TMP-SMZ induced in vivo resistance to the drug after 2 weeks. Empiric therapy for diarrhea with agents other than TMP-SMZ should be considered for HIV-infected persons receiving daily TMP-SMZ prophylaxis.

Effect of trimethoprim-sulfamethoxazole prophylaxis on antimicrobial resistance of fecal Escherichia coli in HIV-infected patients in Tanzania

BACKGROUND

Trimethoprim-sulfamethoxazole (SXT) reduces morbidity and mortality among HIV-infected persons in Africa, but its impact on antimicrobial resistance is of concern.

METHODS

HIV-uninfected (group A), HIV-infected but not requiring SXT (group B), and HIV-infected and eligible for SXT (group C) adults were recruited into a prospective observational cohort study in Moshi, Tanzania. Stool was examined for Escherichia coli nonsusceptible to SXT at baseline and at weeks 1, 2, 4, and 24. General estimating equation models were used to assess differences in susceptibility over time and cross-resistance to other antimicrobials.

RESULTS

Of 181 subjects, 118 (65.1%) were female and the median (range) age was 36 (20 to 72) years. At baseline, E. coli nonsusceptible to SXT was isolated from 23 (53.5%) of 43 patients in group A, 25 (67.6%) of 37 patients in group B, and 37 (64.9%) of 57 patients in group C. The odds ratios (P value) for SXT nonsusceptibility in group C at weeks 1, 2, 4, and 24 compared with baseline were 3.4 (0.013), 3.0 (0.019), 2.9 (0.030), and 1.5 (0.515), respectively. SXT nonsusceptibility was associated with nonsusceptibility to ampicillin, chloramphenicol, ciprofloxacin, and nalidixic acid (P <or= 0.006).

CONCLUSION

In Tanzania, carriage of fecal E. coli nonsusceptible to SXT is common before SXT prophylaxis. Initiation of SXT leads to further loss of susceptibility to SXT and to other antimicrobials.

Review of human immunodeficiency virus type 1-related opportunistic infections in sub-Saharan Africa

Understanding the natural history of human immunodeficiency virus type 1 (HIV-1) and opportunistic infections in sub-Saharan Africa is necessary to optimize strategies for the prophylaxis and treatment of opportunistic infections and to understand the likely impact of antiretroviral therapy. We undertook a systematic review of the literature on HIV-1 infection in sub-Saharan Africa to assess data from recent cohorts and selected cross-sectional studies to delineate rates of opportunistic infections, associated CD4 cell counts, and associated mortality. We searched the MEDLINE database and the Cochrane Database of Systematic Reviews and Cochrane Clinical Trials Register for English-language literature published from 1990 through April 2002. Tuberculosis, bacterial infections, and malaria were identified as the leading causes of HIV-related morbidity across sub-Saharan Africa. Of the few studies that reported CD4 cell counts, the range of cell counts at the time of diagnosis of opportunistic infections was wide. Policies regarding the type and timing of opportunistic infection prophylaxis may be region specific and urgently require further study.

HIV disease and respiratory infection in children

Over one million children world-wide are living with HIV infection and respiratory disease is the commonest cause of morbidity and mortality in these children. The initial presentation of respiratory infection is usually in infancy or early childhood. There is enormous potential to prevent childhood HIV infection that is being realised in industrialised countries but not yet elsewhere. Increasingly, therefore, the burden of HIV disease is in children living in or from non-industrialised countries. This review describes and contrasts the pattern of respiratory infection from both regions. This pattern has changed with the implementation of PCP prophylaxis and the availability of potent antiretroviral therapy for children in resource-rich countries, such as the UK. More data are required from resource-poor regions such as tropical Africa, but it is clear that the major differences reflect greater background risk for respiratory infection and very limited management options rather than specific aetiology.

Primary prevention with cotrimoxazole for HIV-1-infected adults: results of the pilot study in Dakar, Senegal

OBJECTIVES

To assess the efficacy and tolerance of chemoprophylaxis with cotrimoxazole compared with placebo among HIV-1-infected adults.

DESIGN

Randomized, double-blind, placebo-controlled clinical trial in the urban community of Dakar, Senegal.

METHODS

Eligibility criteria were age greater than 15 years, HIV-1 or HIV-1 and HIV-2 dual seropositivity, CD4 cell count lower than 400 copies/mm3, no progressive infection, no previous history of intolerance to sulphonamide, lack of severe anemia or neutropenia, and renal or hepatic failure. Written informed consent was obtained. Recruited patients received 80 mg of trimethoprim and 400 mg of sulphamethoxazole daily or a matching placebo. The main outcomes were survival and the occurrence of clinical events defined as Pneumocystis carinii pneumonia, cerebral toxoplasmosis, bacterial pneumonia, infectious enteritis, bacterial meningitis, urinary tract infection, bacterial otitis and sinusitis, and pyomyositis.

RESULTS

Between September 1996 and March 1998, 297 patients were screened, and 100 were randomized in the study. Demographic, clinical, and biological characteristics of the two groups were similar as was the mean length of follow-up (7.7 months for the cotrimoxazole group vs. 8.0 months for the placebo group). There was no significant difference between the two groups in survival (hazard ratio = 0.84; 95% confidence interval [CI]: 0.36-1.94) in the probability of severe event occurrence, defined as death or hospital admission (hazard ratio = 1.10; 95% CI: 0.57-2.13), or in the probability of clinical event occurrence (hazard ratio = 1.19; 95% CI: 0.55-2.59). Adjustment for initial CD4 cell count did not change these results. A low dose of cotrimoxazole was tolerated well clinically as well as biologically; only one treatment interruption occurred as the result of a moderate cutaneous eruption (grade 2).

CONCLUSION

Our study does not show a beneficial effect of chemoprophylaxis with low-dose cotrimoxazole on survival or occurrence of opportunistic or nonopportunistic infections for HIV-1-infected patients in Dakar, Senegal.

Early chemoprophylaxis with trimethoprim-sulphamethoxazole for HIV-1-infected adults in Abidjan, Côte d'Ivoire: a randomised trial. Cotrimo-CI Study Group

BACKGROUND

In sub-Saharan Africa, various bacterial diseases occur before pneumocystosis or toxoplasmosis in the course of HIV-1 infection, and are major causes of morbidity and mortality. We did a randomised, double blind, placebo-controlled clinical trial at community-health centres in Abidjan, Côte d'Ivoire, to assess the efficacy of trimethoprim-sulphamethoxazole (co-trimoxazole) chemoprophylaxis at early stages of HIV-1 infection.

METHOD

843 HIV-infected patients were screened and 545 enrolled in the study. Eligible adults (with HIV-1 or HIV-1 and HIV-2 dual seropositivity at stages 2 or 3 of the WHO staging system) received co-trimoxazole chemoprophylaxis (trimethoprim 160 mg, sulphamethoxazole 800 mg) daily or a matching placebo. The primary outcome was the occurrence of severe clinical events, defined as death or hospital admission irrespective of the cause. Analyses were by intention to treat.

FINDINGS

Four of the randomised patients were excluded (positive for HIV-2 only). 120 severe events occurred among 271 patients in the co-trimoxazole group and 198 among 270 in the placebo group. Significantly fewer patients in the co-trimoxazole group than in the placebo group had at least one severe event (84 vs 124); the probability of remaining free of severe events was 63.7% versus 45.8% (hazard ratio 0.57 [95% CI 0.43-0.75], p=0.0001) and the benefit was apparent in all subgroups of initial CD4-cell count. Survival did not differ between the groups (41 vs 46 deaths, p=0.51). Co-trimoxazole was generally well tolerated though moderate neutropenia occurred in 62 patients (vs 26 in the placebo group).

INTERPRETATION

Patients who might benefit from co-trimoxazole could be recruited on clinical criteria in community clinics without knowing the patients CD4-cell count. This affordable measure will enable quick public-health intervention, while monitoring bacterial susceptibility and haematological tolerance.

Efficacy of trimethoprim-sulphamethoxazole prophylaxis to decrease morbidity and mortality in HIV-1-infected patients with tuberculosis in Abidjan, Côte d'Ivoire: a randomised controlled trial

BACKGROUND

There is a high incidence of opportunistic infection among HIV-1-infected patients with tuberculosis in Africa and, consequently, high mortality. We assessed the safety and efficacy of trimethoprim-sulphamethoxazole 800 mg/160 mg (co-trimoxazole) prophylaxis in prevention of such infections and in decrease of morbidity and mortality.

METHODS

Between October, 1995, and April, 1998, we enrolled 771 HIV-1 seropositive and HIV-1 and HIV-2 dually seroreactive patients who had sputum-smear-positive pulmonary tuberculosis (median age 32 years [range 18-64], median CD4-cell count 317 cells/microL) attending Abidjan's four largest outpatient tuberculosis treatment centres. Patients were randomly assigned one daily tablet of co-trimoxazole (n=386) or placebo (n=385) 1 month after the start of a standard 6-month tuberculosis regimen. We assessed adherence to study drug and tolerance monthly for 5 months and every 3 months thereafter, as well as rates of admission to hospital.

FINDINGS

Rates of laboratory and clinical adverse events were similar in the two groups. 51 patients in the co-trimoxazole group (13.8/100 person-years) and 86 in the placebo group (25.4/100 person-years) died (decrease In risk 46% [95% CI 23-62], p<0.001). 29 patients on co-trimoxazole (8.2/100 person-years) and 47 on placebo (15.0/100 person-years) were admitted to hospital at least once after randomisation (decrease 43% [10-64]), p=0.02). There were significantly fewer admissions for septicaemia and enteritis in the co-trimoxazole group than in the placebo group.

INTERPRETATION

In HIV-1-infected patients with tuberculosis, daily co-trimoxazole prophylaxis was well tolerated and significantly decreased mortality and hospital admission rates. Our findings may have important implications for improvement of clinical care for such patients in Africa.