Risk factors for negative sputum acid-fast bacilli smears in pulmonary tuberculosis: results from Dakar, Senegal, a city with low HIV seroprevalence.

SETTING: Two teaching hospitals in Dakar, Senegal, a West African country with a low prevalence of human immunodeficiency virus (HIV) infection. OBJECTIVE: To determine whether patients with HIV-associated pulmonary tuberculosis have fewer acid-fast bacilli (AFB) in their sputum as assessed by routine microscopy, and to correlate the findings with systematically obtained clinical, radiographic and laboratory variables. DESIGN: Prospective study from November 1995 to October 1996 of 450 consecutive patients diagnosed with pulmonary tuberculosis. RESULTS: Tuberculosis was diagnosed in 380 patients (84.4%) by positive bacteriology, in 61 (13.6%) by a favorable response to anti-tuberculosis chemotherapy, and in nine (2.0%) by the presence of a miliary radiographic pattern. Forty (8.9%) patients were HIV-seropositive. AFB-negative smears were found in 14/40 (35.0%) of the HIV-seropositive patients with pulmonary tuberculosis compared with 71/410 (17.3%) of the seronegative patients (risk ratio [RR] = 2.02, 95% confidence interval [CI] 1.26-3.24, P = 0.01). Multivariate analysis revealed that AFB smear negativity was associated with absence of cavitation (P = 0.002), lack of cough (P = 0.005), the presence of HIV seropositivity (P = 0.02), a CD4+ cell count above 200/mm3 (P = 0.02), and age over 40 years (P = 0.03). CONCLUSIONS: Compared with HIV-seronegative patients with pulmonary tuberculosis, seropositive patients in Dakar, Senegal, are more likely to have negative sputum-AFB smears. This phenomenon has now been observed in seven of eight sub-Saharan African countries with varying HIV seroprevalence from which reports are available.

Tuberculosis-associated severe CD4+ T-lymphocytopenia in HIV-seronegative patients from Dakar. SIDAK Research Group.

OBJECTIVES: To determine the frequency and associated features of severe CD4+ T-lymphocytopenia (<300 cells/mm(3)) in HIV-seronegative patients with tuberculosis. METHODS: Statistical analysis of 430 consecutively enrolled HIV-seronegative inpatients with tuberculosis in two teaching hospitals in Dakar, Senegal. RESULTS: The mean CD4 + cell count was 602+/-318.3 cells/mm(3). CD4 + cell counts were below 300 cells/mm(3)in 62 patients (14.4%). Patients with fewer than 300 CD4+ cells/mm(3)differed from those with higher counts in being less likely to have a positive smear for acid-fast bacilli; in having a higher frequency of extrapulmonary involvement (pleural effusion, adenopathy and miliary disease) and oral candidiasis; and in having smaller tuberculin reactions, lower haemoglobin levels, less cavitation and less patchy infiltration. After adjustment for gender and age, all differences remained except miliary disease. CONCLUSIONS: A substantial percentage (14.4%) of HIV-seronegative hospitalized patients for tuberculosis in a West African country presented with severe CD4 + T-lymphocyte depletion and had clinical and radiographic features indicative of more advanced disease and accompanying immunodepression. These results and those already published suggest that tuberculosis should be regarded as one of the diseases associated with a subgroup of patients with "idiopathic CD4 + T-lymphocytopenia".

Sexually transmitted diseases and risk of HIV infection in men attending a sexually transmitted diseases clinic in Dakar, Senegal.

This cross-sectional study was carried out among male outpatients with symptoms of STDs at the STD reference centre at the Institute of Social Hygiene (IHS), Dakar, Senegal, from March 1989 through May 1991. This study was used to determine the prevalence of STDs and HIV among male patients attending an STD clinic and to identify their socio-demographic characteristics and risk factors. A total of 975 patients were enrolled in the study. The most common syndromes were urethritis (76%) and genital ulcers (22%). Considering single infections, the major STD agents were Neisseria gonorrheae (N.gonorrheae, 30%), Chlamydia trachomatis (C.trachomatis, 15%), Treponema pallidum (T.pallidum, 12%), and Haemophilus ducreyi (H.ducreyi, 7%). HIV prevalence was 2.6 percent (25/975). After multivariate analysis, the risk factors associated with HIV infection were a history of sex with prostitutes (odds ratio [OR] = 8.6, 95% confidence interval [CI] = 2.0-37.8), unprotected sexual contact (OR = 5.6, 95% CI = 1.2-25.0), a history of urethritis (OR = 3.4, 95% CI = 1.3-8.9), current STDs due to H.ducreyi or T.pallidum (OR = 6.1, 95% CI = 2-18.8), and mixed STD infection (OR = 5.3, 95% CI = 1.3-21.8). HIV prevalence was quite low in this population compared to similar studies of STD patients from other sub-Saharan African countries. Neisseria gonorrheae and Chlamydia trachomatis were the leading causes of STDs. A history of risky sexual behaviour, previous STDs, current genital ulcers, and mixed STD infections were associated with HIV infection. Further studies are necessary to determine changes in the relationship of STDs and HIV infection in this population.

[Importance of culture media choice in the isolation of Haemophilus ducreyi. Experience in Senegal]. / Importance du choix d'un milieu de culture dans l'isolement de Haemophilus ducreyi. Expérience du Sénégal.

Genital ulcerations typify one of the major reasons clients seek STD consultation in developing countries. The usual etiologies are syphilis, chancroid and herpes. The ideal diagnostic approach is to undertake complete laboratory examination that are rarely possible in structure destitute of laboratory analysis possibilities which is the case for most of the STD transmission agents. Chancroid is caused by Haemophilus ducreyi, a short Gram negative bacteria. The bacteriological diagnosis is based on direct examination, isolation and identification of the bacteria. The nutritive exigence of the bacteria required 3 medium of isolation (PPLO base Pasteur), GC base (GIBCO) and Muller Hinton base (Becton & Dickinson, with "chocolate" agar) have been tested from the chancre samples of 108 male patients who had a median age of 31 years. Direct exams were positive in 66 cases (61%) and culture exams positive in 53 cases (49%). The Muller Hinton base with "chocolate" agar produced the best results and seems to be the medium of choice for isolated strains in Senegal. The culture mediums currently used in Europe are apparently inappropriate for the germ culture in Senegal. We have also observed that all the isolated strains were producers of beta-lactamase. Antibiotic treatment before the sample swab is taken seems to have an inhibiting effect on the culture. Direct examination with a sensibility of 94.3% and a specificity of 70.9% remains sufficient in routine presumptive diagnosis in endemic areas.

[Viral markers of acute hepatitis: A, B, C, D, and E in Dakar. October 92 - October 93]. / Marqueurs viraux des hépatites aiguës: A, B, C, D et E à Dakar. Octobre 92-Octobre 93.

Inside of 95 patients presented in Hospital with presumed hepatitis: 77 were recruted with liver cytolysis (Amino-Transferases AT > 80 UI/ml) and included in this study. Study of serologic viral markers (A, B, C, D and E type) permited to prove viral acute hepatitis infection and 49 patients were recruted inside the 77 cytolytic cases. Inside these 49 cases: 44% presented enteritic contamination with HAV/HEV markers, 36% with HBV markers: HBs/HBc, 6% with HBs/HBe markers, 10% with HDV marker, 4% with HCV marker. 28 patients presented any viral acute hepatitis marker and in this case can be evocated other hepatitis origin: viral hepatitis type (EBV), CMV, chronic hepatitis evolution, malaria hepatitis or toxic hepatitis.

[Preliminary study of pneumocystis carinii pneumonia diagnosed by induced expectoration in HIV positive patients in Dakar]. / Etude préliminaire de la pneumopathie à Pneumocystis carinii diagnostiquée par expectoration induite chez des patients VIH positifs à Dakar.

Rapid noninvasive diagnosis of Pneumocystis carinii from induced liquefied sputum is a very easy and not costly method. It was using for a first time at the Infectious Diseases Department at Dakar in 27 HIV seropositive patients from July to November 1992. Six cases of Pneumocystis carinii pneumonia (PCP) was diagnosed, with a prevalence of 22.2%. In this study PCP was found in both HIV-1 and HIV-2 patients. Clinical and radiological aspects are not specific. PCP was also found in patients with CD4 below than 200 per cubic millimeter. Co-infection with Mycobacterium tuberculosis is possible.

PIP: Between July and November 1992, in Senegal, health workers took sputum samples from 27 HIV-positive patients (19 men and 8 women) aged 20-66 at the infectious disease service of Fann University Hospital Center in Dakar so researchers could determine the prevalence of Pneumocystis carinii pneumonia among HIV-positive patients and specify the characteristics of P. carinii pneumonia among HIV-positive patients in Dakar. The simple, effective, and low-cost technique used was coloration of the sputum with Toluidine O. 70.3% had HIV-1 infection, 26% had HIV-2 infection, and 3.7% had both HIV-1 and HIV-2 infection. 55.5% had CD4 counts under 200/cu. mm. 40.7% had higher CD4 counts. The CD4 count could not be measured in one patient. Six (22.2%) tested positive for P. carinii. Four of the patients with P. carinii pneumonia were HIV-1 positive. The other two were HIV-2 positive. 83.3% had fever and were becoming thinner. 33.3% had a cough. 16.6% had difficulty breathing. One patient with P. carinii infection was asymptomatic. Two pneumocystis patients had diffuse interstitial infiltration and perihilar infiltration. Another patient also had pulmonary tuberculosis. The CD4 count for 80% of HIV-infected patients who tested positive for P. carinii pneumonia was less than 200/cu. mm.

[Pneumocystosis in HIV infected patients presenting with acid-fast bacilli negative pneumopathy at the Central University Hospital at Dakar]. / La pneumocystose chez les sujets infectés par le VIH presentant une pneumopathie à BAAR négative au CHU de Fann à Dakar.

Pneumocystosis is an opportunist parasitic disease which occurs currently at Europe and United States in HIV infected patients. In Africa, the disease is not current. Pneumocystosis has been detected in the Fann medical universitary center at Dakar from HIV infected patients with acido alcoholo resistant bacilli negative pneumopathy. Analysis of broncho alveolar liquid(BAL) of 29 patients after Giemsa and Blue of Toluidin O staining allowed isolating of two cases of pneumocystosis. A man and a woman were the patients. They were HIV1 positive with at X ray bilateral interstitial syndrome. The CD4 lymphocytes count of the one was lower than 200/mm3 and for the other it was higher than 200/mm3.

[Severe acute colitis: two fatal cases in Dakar]. / La colite aiguë grave : deux observations mortelles à Dakar.

OBJECTIVE: Severe acute colitis (SAC) is one of the major complications of inflammatory bowel disease (IBD), especially ulcerative colitis, and it is life-threatening. Although IBD is considered rare in sub-Saharan Africa, we report 2 fatal cases of SAC in Senegalese patients with ulcerative colitis in Dakar. CASES: One patient was a 73-year-old man and the other a 35-year-old woman. In both cases, the diagnosis was preceded by a chronic dysenteric syndrome (febrile in the woman). Despite antibiotic treatment for potential infectious colitis, both patients' condition worsened. Second-line treatment of parenteral corticosteroids did not prevent the occurrence of intestinal perforation for the man, who developed multiorgan failure. The woman developed toxic megacolon during antibiotic treatment, and it was fatal despite bolus corticosteroids: cardiovascular collapse with shock (case 2) occurred before emergency surgery could begin. Conclusion: in subtropical zones where infectious colitis predominates, it is important to consider the diagnosis of SAC in patients with ulcerative colitis and to begin appropriate treatment despite the fear of infection and the difficulty of accessibility to endoscopic exploration.

AIDS caused by HIV1 and HIV2 infection: are there clinical differences? Results of AIDS surveillance 1986-97 at Fann Hospital in Dakar, Senegal.

OBJECTIVE: To compare the clinical manifestations observed in AIDS patients infected with HIV2 and HIV1 infection. METHODS: The medical records of AIDS patients hospitalized between January 1986 and July 1997 at the Department of Infectious Diseases of Fann Hospital, Dakar, were reviewed. RESULTS: 599 hospitalizations (76%) were HIV1 seropositive patients, 137 (17%) were HIV2 seropositive patients and 54 (7%) were patients serologically dually reactive to HIV1 and HIV2. There was no significant difference in medium CD4 lymphocyte count between patients with HIV1 and HIV2 infection. Chronic diarrhoea and diarrhoea caused by bacterial infections were more frequently observed in HIV2-infected individuals. Oral candidiasis and chronic fever were more often noted in patients with HIV1 infection. Bacterial and cryptococcal meningitis was only observed among patients with HIV1 infection. CONCLUSIONS: Certain clinical differences were observed comparing AIDS patients with HIV1 and those with HIV2 infection. As there is no clear physiopathological explanation for these differences, additional studies with larger numbers of AIDS patients are needed to determine whether these differences are real.