Tuberculosis burden in an urban population: a cross sectional tuberculosis survey from Guinea Bissau.

BACKGROUND: Little is known about the prevalence of pulmonary tuberculosis (TB) in low income countries. We conducted a cross sectional survey for pulmonary TB and TB symptoms in Bissau, Guinea-Bissau, in an urban cohort with known HIV prevalence. TB surveillance in the area is routinely based on passive case finding. METHODS: Two cohorts were selected based on a previous HIV survey, but only 52.5% of those enrolled in the adult cohort had participated in the HIV survey. One cohort included all adults living in 384 randomly selected houses; in this cohort 8% (135/1687) were HIV infected. The other included individuals 50 years or older from all other houses in the study area; of these 11% (62/571) were HIV infected. Symptom screening was done through household visits using a standardised questionnaire. TB suspects were investigated with sputum smear microscopy and X-ray. RESULTS: In the adult cohort, we found 4 cases among 2989 individuals screened, giving a total TB prevalence of 134/100,000 (95% CI 36-342/100,000). In the >50 years cohort, we found 4 cases among 571 individuals screened, giving a total prevalence of 701/100,000 (191-1784/100.000). Two of the eight detected TB cases were unknown by the TB program. Of the total TB cases five were HIV uninfected while three had unknown HIV status. The prevalence of TB symptoms was 2.1% (63/2989) and 10.3% (59/571) in the two cohorts respectively. CONCLUSIONS: In conclusion we found a moderately high prevalence of pulmonary TB and TB symptoms in the general population, higher among elderly individuals. By active case finding unknown cases were detected. Better awareness of TB and its symptoms needs to be promoted in low income settings.

Vitamin D as supplementary treatment for tuberculosis: a double-blind, randomized, placebo-controlled trial.

RATIONALE: Vitamin D has been shown to be involved in the host immune response toward Mycobacterium tuberculosis. OBJECTIVES: To test whether vitamin D supplementation of patients with tuberculosis (TB) improved clinical outcome and reduced mortality. METHODS: We conducted a randomized, double-blind, placebo-controlled trial in TB clinics at a demographic surveillance site in Guinea-Bissau. We included 365 adult patients with TB starting antituberculosis treatment; 281 completed the 12-month follow-up. The intervention was 100,000 IU of cholecalciferol or placebo at inclusion and again 5 and 8 months after the start of treatment. MEASUREMENTS AND MAIN RESULTS: The primary outcome was reduction in a clinical severity score (TBscore) for all patients with pulmonary TB. The secondary outcome was 12-month mortality. No serious adverse effects were reported; mild hypercalcemia was rare and present in both arms. Reduction in TBscore and sputum smear conversion rates did not differ among patients treated with vitamin D or placebo. Overall mortality was 15% (54 of 365) at 1 year of follow-up and similar in both arms (30 of 187 for vitamin D treated and 24 of 178 for placebo; relative risk, 1.19 [0.58-1.95]). HIV infection was seen in 36% (131 of 359): 21% (76 of 359) HIV-1, 10% (36 of 359) HIV-2, and 5% (19 of 357) HIV-1+2. CONCLUSIONS: Vitamin D does not improve clinical outcome among patients with TB and the trial showed no overall effect on mortality in patients with TB; it is possible that the dose used was insufficient. Clinical trial registered with www.controlled-trials.com/isrctn (ISRCTN35212132).

Serum 25-hydroxyvitamin D in a West African population of tuberculosis patients and unmatched healthy controls.

BACKGROUND: Little is known regarding vitamin D deficiency (VDD) in African populations and in tuberculosis (TB) patients. VDD has been shown to be associated with TB. OBJECTIVE: We aimed to compare the degree of vitamin D insufficiency (VDI) and VDD in TB patients and healthy adult controls in a West African population. DESIGN: An unmatched case-control study was performed at a Demographic Surveillance Site in Guinea-Bissau. Serum 25-hydroxyvitamin D(3) [25(OH)D(3)] concentrations were measured in 362 TB patients and in 494 controls. RESULTS: Hypovitaminosis D [25(OH)D(3)

Chlamydia antibody response in healthy volunteers immunized with nonchlamydial antigens: a randomized, double-blind, placebo-controlled study.

Serological analysis is often used for the diagnosis of chlamydial infections. However, an increase in Chlamydia antibodies has been reported in patients with parvovirus and Mycoplasma infections. Whether this antibody response is the result of dual infection or nonchlamydial antigen stimulation is unknown. In a randomized study, 48 healthy volunteers either were immunized against yellow fever, polio, diphtheria, and tetanus (the group receiving intervention with nonchlamydial antigen) or received saline injections (the placebo group). The change in antibody levels was compared between the 2 groups. The Chlamydia recombinant lipopolysaccharide enzyme-linked immunosorbent assay (Medac) showed an increase in the antibody titer in the intervention group, compared with that in the control group (for immunoglobulin M, P=.004; for immunoglobulin A, P=.038; and for immunoglobulin G, P=.056), but no differences between study groups was found when the C. pneumoniae enzyme immunoassay (EIA; ThermoLabsystems), the C. pneumoniae EIA (Medac), and the microimmunofluorescence test (MRL) were used. An increase in antibodies to Chlamydia organisms can be measured after exposure to nonchlamydial antigens, depending on the test used.

Activation of the respiratory burst by Pneumocystis carinii. Efficiency of different antibody isotypes, complement, lung surfactant protein D, and mannan-binding lectin.

The effect of opsonization of Pneumocystis carinii with different antibody classes, complement, mannan-binding lectin (MBL), and lung surfactant protein D (SP-D) on respiratory burst activation was studied. Antibodies were obtained by affinity chromatography, complement from a hypogammaglobulinaemic patient, and phagocytic cells from blood donors. Respiratory burst activation was measured by chemiluminescence (CL). With freshly isolated neutrophils the combination of antibodies and complement but not antibody alone, had opsonizing properties. With neutrophils cultured for 20 h, however, IgG increased the CL response. In macrophages P. carinii opsonized with IgG alone induced a CL response proportional to the antibody titre used. With IgA an effect, albeit lower, was also seen, whereas IgM alone was inefficient. The combined effect of antibodies and complement increased the response significantly for all three antibody classes, IgG and complement giving the largest response. Binding of MBL to P. carinii and Candida albicans was demonstrated; however, only the former stimulated activation of the respiratory burst. SP-D did not bind to either microorganism and had no effect on the respiratory burst. It is concluded that IgG, IgA and complement are important opsonizing factors in infections involving P. carinii. The relative importance varies with the type of phagocytic cell studied.

The occurrence of Chlamydia pneumoniae, Mycoplasma pneumoniae, and herpesviruses in otitis media with effusion.

In a previous report we found Chlamydia (C.) pneumoniae to be present in middle ear fluids (MEE) from older children with otitis media with effusion (OME). However, OME is a disease of younger children the present study was conducted in toddlers. MEEs (n = 150) and nasopharynx samples (n = 83) from children with OME was analyzed by PCR for the presence of C. pneumoniae and Mycoplasma (M.) pneumoniae. C. pneumoniae was not present in any and M. pneumoniae only in one of the MEEs, and these pathogens could be demonstrated in one and two nasopharynx samples, respectively. Further, 133 MEEs were analyzed by PCR for the presence of the 8 human herpesviruses, and all samples were found to be negative. We conclude that neither C. pneumoniae or M. pneumoniae, or any of the 8 human herpesviruses seems to play a major role in the pathogenesis of OME in early childhood OME.

[Atherosclerosis and Chlamydia pneumoniae]. / Aterosklerose og Chlamydia pneumoniae.

Chlamydia pneumoniae could be associated with the risk of developing atherosclerosis and an increased risk of thromboembolic complications. However, the evidence of an association seems to be declining and there is no evidence of causality. The effect of antibiotic treatment in cardiovascular disease has been explored in epidemiologic studies and in randomised controlled trials. Data suggest a protective but short-lasting effect of macrolide antibiotics on cardiovascular disease. The effect could be the result of anti-bacterial as well as anti-inflammatory properties. Ongoing larger and longer lasting treatment trials could provide better measures of the effects of antibiotic treatment, although they will not clarify the role of C. pneumoniae. Currently, there is no indication for treating cardiovascular disease with antibiotics.

Chlamydia pneumoniae and cardiovascular disease.

Chlamydia pneumoniae has been detected in atherosclerotic plaques, while seropositivity to this organism confers a slightly increased risk of coronary events. However, no aetiological link has been established; a major difficulty when investigating this link is the lack of a gold standard for diagnosing chronic vessel infection. The outcomes of case-control studies and prospective trials of macrolides in treatment and prevention of cardiovascular disease have been ambiguous but suggest a short-term preventive effect. Whether this is due to the antimicrobial or anti-inflammatory activity of the macrolides is unknown. Larger and longer prospective trials currently under way may provide better insight into the association of C. pneumoniae with cardiovascular disease. At present, there is no justification for treating cardiovascular disease with antibiotics.