Molecular and clinicopathologic characterization of pediatric histiocytoses

The spectrum of somatic mutations in pediatric histiocytoses and their clinical implications are not fully characterized, especially for non-Langerhans cell histiocytosis (-LCH) subtypes. A cohort of 415 children with histiocytosis from the French histiocytosis registry was reviewed and analyzed for BRAFV600E . Most BRAFWT samples were analyzed by next-generation sequencing (NGS) with a custom panel of genes for histiocytosis and myeloid neoplasia. Of 415 case samples, there were 366 LCH, 1 Erdheim-Chester disease, 21 Rosai-Dorfman disease (RDD), 21 juvenile xanthogranuloma (JXG, mostly with severe presentation), and 6 malignant histiocytosis (MH). BRAFV600E was the most common mutation found in LCH (50.3%, n = 184). Among 105 non-BRAFV600E -mutated LCH case samples, NGS revealed mutations as follows: MAP2K1 (n = 44), BRAF exon 12 deletions (n = 26), and duplications (n = 8), other BRAF V600 codon mutation (n = 4), and non-MAP-kinase pathway genes (n = 5). Wild-type sequences were identified in 17.1% of samples. BRAFV600E was the only variant significantly correlated with critical presentations: organ-risk involvement and neurodegeneration. MAP-kinase pathway mutations were identified in seven RDD (mostly MAP2K1) and three JXG samples, but most samples were wild-type on NGS. Finally, two MH samples had KRAS mutations, and one had a novel BRAFG469R mutation. Rarely, we identified mutations unrelated to MAP-kinase pathway genes. In conclusion, we characterized the mutational spectrum of childhood LCH and clinical correlations of variants and subtypes. Variants responsible for JXG and RDD were not elucidated in more than half of the cases, calling for other sequencing approaches.

Outbreak of an acute aflatoxicosis in Tanzania during 2016

In June 2016, an outbreak of an unknown disease was reported to affect clusters of families in two regions of the central part of Tanzania. A rapid epidemiological survey was conducted in the affected villages, with a detailed house-to-house survey in selected households. A total of 68 cases occurred between 14 May and 14 November 2016, of which 20 died, making a case fatality rate of 30%. Over 50% of the cases were below the age of 15 years. The cases presented with jaundice (n=60), abdominal pain (n=59), vomiting (n=56), diarrhoea (n=34) and ascites (n=32). The responsible food item appeared to be home grown maize. The rate ratio indicated that the occurrence of illnesses was associated with ingestion of food contaminated with high levels of aflatoxins (contamination range: 10-51,100 μg/kg and 2.4-285 μg/kg for case and control households, respectively). Serum aflatoxin biomarker indicated that cases were more likely to have higher than 1000 pg/mg aflatoxin-albumin adduct level in their sera compared to controls (Odds Ratio = 13.5; 95% confidence intervals = 1.5-165.3; range of aflatoxin-albumin adduct level = 36- 32,800 pg/mg for cases and 10-4020 pg/mg for controls). Beside aflatoxins, maize samples were also contaminated with high levels of fumonisins (range of contamination; 945-12,630 μg/kg) with 8 of 10 samples analysed from case households co-contaminated with both toxins at levels above the maximum limit of 5 or 10 μg/kg set for AFB1 or total aflatoxins and 2,000 μg/kg for fumonisins. Clinical presentation and high levels of aflatoxin in food samples coupled with high levels of serum aflatoxin-albumin adducts among the cases support the causal role of aflatoxins.

CDKN2A Depletion Causes Aneuploidy and Enhances Cell Proliferation in Non-Immortalized Normal Human Cells

Aneuploidy is a common feature of cancer cells and may contribute to cellular transformation and cancer development. In this study, we found that significant down-regulation of CDKN2A, CHEK2, CDCA8, TP53BP1, and CCNDBP1 led to chromosome imbalances in two diploid non-immortalized human cell lines; however, only CDKN2A inhibition enhanced cell proliferation and additionally up-regulated three cell cycle control genes: CDCA8, AURKA, and CCND. These results confirm that CDKN2A is a tumor suppressor gene driving human cancer development by inducing cell aneuploidy and cell cycle up-regulation.

Motivations to participate in a Phase I/II HIV vaccine trial: A descriptive study from Dar es Salaam, Tanzania

Background

The search for an efficacious HIV vaccine is a global priority. To date only one HIV vaccine trial (RV144) has shown modest efficacy in a phase III trial. With existing different HIV-1 subtypes and frequent mutations, multiple trials are needed from different geographical sites particularly in sub-Saharan Africa where most HIV infections occur. Thus, motivations to participate in HIV vaccine trials among Tanzanians need to be assessed. This paper describes the motives of Police Officers who showed great interest to volunteer in HIVIS-03 in Dar es Salaam, Tanzania.

Methods

A descriptive cross-sectional study was conducted among Police Officers who showed interest to participate in the HIVIS-03, a phase I/II HIV vaccine trial in Dar es Salaam. Prior to detailed training sessions about HIV vaccine trials, the potential participants narrated their individual motives to participate in the trial on a piece of paper. Descriptive analysis using content approach and frequency distributions were performed.

Results

Of the 265 respondents, 242 (91.3 %) provided their socio-demographic characteristics as well as reasons that would make them take part in the proposed trial. Majority, (39.7 %), cited altruism as the main motive. Women were more likely to volunteer due to altruism compared to men (P < 0.01). Researchers’ explanations about HIV/AIDS vaccine studies motivated 15.3 %. More men (19.6 %) than women (1.7 %) were motivated to volunteer due to researchers’ explanations (P < 0.001). Also, compared to other groups, those unmarried and educated up to secondary level of education were motivated to volunteer due to researchers’ explanation (P < 0.05). Other reasons were: desire to become a role model (18.6 %); to get knowledge for educating others (14.0 %); to cooperate with researchers in developing an HIV vaccine (9.5 %); to get protection against HIV infection (7.0 %), and severity of the disease within families (6.2 %). These results were supported by testimonies from both men and women.

Conclusions

Participation in an HIV vaccine trial in a Tanzanian context is likely to be influenced by altruism and comprehensive education about the trial. Gender differences, marital status and education level need to be considered to enhance participation in future HIV vaccine trials.

Pharmacokinetic and pharmacogenomic modelling of the CYP3A activity marker 4β-hydroxycholesterol during efavirenz treatment and efavirenz/rifampicin co-treatment

OBJECTIVES

To assess the effect of the major efavirenz metabolizing enzyme (CYP2B6) genotype and the effects of rifampicin co-treatment on induction of CYP3A by efavirenz.

PATIENTS AND METHODS

Two study arms (arm 1, n = 41 and arm 2, n = 21) were recruited into this study. In arm 1, cholesterol and 4β-hydroxycholesterol were measured in HIV treatment-naive patients at baseline and then at 4 and 16 weeks after initiation of efavirenz-based antiretroviral therapy. In arm 2, cholesterol and 4β-hydroxycholesterol were measured among patients taking efavirenz during rifampicin-based tuberculosis (TB) treatment (efavirenz/rifampicin) just before completion of TB treatment and then serially following completion of TB treatment (efavirenz alone). Non-linear mixed-effect modelling was performed.

RESULTS

A one-compartment, enzyme turnover model described 4β-hydroxycholesterol kinetics adequately. Efavirenz treatment in arm 1 resulted in 1.74 (relative standard error = 15%), 3.3 (relative standard error = 33.1%) and 4.0 (relative standard error = 37.1%) average fold induction of CYP3A for extensive (CYP2B6*1/*1), intermediate (CYP2B6*1/*6) and slow (CYP2B6*6/*6) efavirenz metabolizers, respectively. The rate constant of 4β-hydroxycholesterol formation [mean (95% CI)] just before completion of TB treatment [efavirenz/rifampicin co-treatment, 7.40 × 10(-7) h(-1) (5.5 × 10(-7)-1.0 × 10(-6))] was significantly higher than that calculated 8 weeks after completion [efavirenz alone, 4.50 × 10(-7) h(-1) (4.40 × 10(-7)-4.52 × 10(-7))]. The CYP3A induction dropped to 62% of its maximum by week 8 of completion.

CONCLUSIONS

Our results indicate that efavirenz induction of CYP3A is influenced by CYP2B6 genetic polymorphisms and that efavirenz/rifampicin co-treatment results in higher induction than efavirenz alone.

Nutritional status of HIV-infected women with tuberculosis in Dar es Salaam, Tanzania

SETTING

Tuberculosis (TB) treatment clinics in Dar es Salaam, Tanzania.

OBJECTIVE

To quantify anthropometrics and intake of en-ergy and protein among human immunodeficiency virus (HIV) positive women with TB.

DESIGN

HIV-positive women with newly diagnosed TB were assessed on their anthropometric characteristics and dietary intake. Energy and protein intake were determined using Tanzania food composition tables and compared with standard recommendations. Patients were re-evaluated after 4-6 months of anti-tuberculosis treatment.

RESULTS

Among 43 women, the baseline median CD4 count was 209 cells/µl (range 8-721); 19 (44%) had a CD4 count of <200; 20 (47%) were on antiretroviral therapy. Body mass index was <18.5 kg/m(2) in 25 (58%); the median food insecurity score was 6. The median level of kcal/day was 1693 (range 1290-2633) compared to an estimated need of 2658; the median deficit was 875 kcal (range -65-1278). The median level of protein/day was 42 g (range 27-67) compared to 77 g estimated need; the median protein deficit was 35 g (range 10-50). The median weight gain among 29 patients after 4-6 months was 6 kg.

CONCLUSION

HIV-positive women with TB have substantial 24-h deficits in energy and protein intake, report significant food insecurity and gain minimal weight on anti-tuberculosis treatment. Enhanced dietary education together with daily supplementation of 1000 kcal with 40 g protein may be required.

New vaccines for the prevention of tuberculosis in human immunodeficiency virus infection

The prevention of human immunodeficiency virus (HIV) associated tuberculosis (TB) remains challenging. Several vaccines against TB have advanced to clinical trials in patients with HIV infection. The DarDar Trial, a large, randomized, placebo-controlled efficacy trial conducted in Tanzania, has demonstrated that a multiple dose series of an inactivated whole cell mycobacterial vaccine is safe in HIV and can prevent HIV-associated TB in patients with childhood bacille Calmette-Guérin vaccination and CD4 counts of ≥200 cells/mm(3). These developments offer promise that in the not too distant future immunization with an effective vaccine against TB can be added to other strategies for the prevention of HIV-associated TB. This expanded approach is referred to as the Five 'I's': intensified case finding, infection control, isoniazid preventive therapy (IPT), initiation of antiretroviral therapy (ART), and immunization against TB. We encourage additional studies of new TB vaccines in HIV, and propose a strategy to reduce the risk of TB by integrating IPT, ART and immunization into routine HIV care. At the time of HIV diagnosis, patients with CD4 counts of ≥200 cells/mm(3) could receive immunization, IPT and, as appropriate, ART. In patients presenting with lower CD4 counts or already on ART, immunization could be initiated at CD4 counts of ≥200 cells/mm(3) to add to the protection afforded by IPT and ART.

Completion of isoniazid preventive therapy and survival in HIV-infected, TST-positive adults in Tanzania

SETTING

The World Health Organization recommends the use of isoniazid preventive therapy (IPT) for human immunodeficiency virus (HIV) infected patients with a positive tuberculin skin test (TST). However, due to concerns about the effectiveness of IPT in community health care settings and the development of drug resistance, these recommendations have not been widely implemented in countries where tuberculosis (TB) and HIV co-infection is common.

OBJECTIVE

To evaluate the effectiveness of IPT on survival and TB incidence among HIV-infected patients in Tanzania.

DESIGN

A cohort study nested within a randomized trial of HIV-infected adults with baseline CD4 counts of ≥ 200 cells/μ l was conducted to compare survival and incidence of active TB between TST-positive subjects who did or did not complete 6 months of IPT in the period 2001-2008.

RESULTS

Of 558 TST-positive subjects in the analytic cohort, 488 completed 6 months of IPT and 70 did not. Completers had a decrease in mortality compared to non-completers (HR 0.4, 95%CI 0.2-0.8). However, the protective effect of IPT on the incidence of active TB was non-significant (HR 0.6, 95%CI 0.3-1.3).

CONCLUSION

Completion of IPT is associated with increased survival in HIV-infected adults with CD4 counts ≥ 200 cells/μ l and a positive TST.

Disseminated tuberculosis in human immunodeficiency virus infection: ineffective immunity, polyclonal disease and high mortality

BACKGROUND

Disseminated tuberculosis (TB) is a major cause of death in patients with the acquired immune-deficiency syndrome (AIDS), but its pathogenesis and clinical features have not been defined prospectively.

METHODS

Human immunodeficiency virus (HIV) infected adults with a CD4 count ≥ 200 cells/μl and bacille Calmette-Guérin scar underwent immunologic evaluation and subsequent follow-up.

RESULTS

Among 20 subjects who developed disseminated TB, baseline tuberculin skin tests were ≥15 mm in 14 (70%) and lymphocyte proliferative responses to Mycobacterium tuberculosis were positive in 14 (70%). At the time of diagnosis, fever ≥2 weeks plus ≥5 kg weight loss was reported in 16 (80%) patients, abnormal chest X-rays in 7/17 (41%), and positive sputum cultures in 10 (50%); median CD4 count was 30 cells/μl (range 1-122). By insertion sequence (IS) 6110 analysis, 14 (70%) blood isolates were clustered and 3/8 (37%) concurrent sputum isolates represented a different strain (polyclonal disease). Empiric TB treatment was given to eight (40%) patients; 11 (55%) died within a month.

CONCLUSIONS

Disseminated TB in HIV occurs with cellular immune responses indicating prior mycobacterial infection, and IS6110 analysis suggests an often lethal combination of reactivation and newly acquired infection. Control will require effective prevention of both remotely and recently acquired infection, and wider use of empiric therapy in patients with advanced AIDS and prolonged fever.

Low BMI and falling BMI predict HIV-associated tuberculosis: a prospective study in Tanzania

BACKGROUND

Low body mass index (BMI) is a known risk factor for tuberculosis (TB) in people without human immunodeficiency virus (HIV), but there are no prospective studies linking BMI to the risk of HIV-associated TB.

DESIGN

In HIV-infected adults with CD4 counts ≥ 200 cells/μl receiving placebo in a TB booster vaccine trial in Dar es Salaam, Tanzania, we measured BMI at baseline and Year 1, and related baseline BMI and change in BMI to the risk of developing TB.

RESULTS

We documented 92 cases of TB among 979 subjects followed for a mean of 3.2 years. Compared to subjects who did not develop TB, subjects who developed TB had a lower baseline BMI (23.2 vs. 24.6 kg/m(2), P = 0.006), and a greater BMI decline from baseline to Year 1 (-0.4 vs. 0.6 kg/m(2), P < 0.001). In multivariate analyses, baseline BMI was associated with the risk of developing TB (hazard ratio [HR] per kg/m(2) 0.94, 95%CI 0.90-0.99, P = 0.028), as was the change in BMI from baseline to Year 1 (HR per kg/m(2) 0.79, 95%CI 0.71-0.87, P < 0.001). Subjects with a baseline BMI < 17 kg/m(2) were more likely to develop TB (HR 3.72, 95%CI 1.16-12.0, P = 0.028).

CONCLUSION

Low and falling BMI predict HIV-associated TB.

Enhancing adherence to antiretroviral therapy at the HIV clinic in resource constrained countries; the Tanzanian experience

OBJECTIVE

To evaluate various strategies aimed at improving adherence to antiretroviral therapy (ART).

METHODS

Patients initiated on ART at Muhimbili National Hospital HIV clinic were randomly assigned to either regular adherence counseling, regular counseling plus a calendar, or regular counseling and a treatment assistant. Patients were seen monthly; during these meetings self-reported adherence to treatment was recorded. Disease progression was monitored clinically and immunologically.

RESULTS

Of the 621 patients randomized, 312 received regular counseling only, 242 regular counseling and calendars, while 67 had treatment assistants in addition to regular counseling. The mean (SD) follow-up time was 14.5 (4.6) months. During follow-up 20 (3.2%) patients died, and 102 (16.4%) were lost to follow-up; this was similar in all groups. In 94.8% of all visits, patients reported to have adhered to treatment. In only 39 (0.7%) visits did patients report a < or = 95% adherence. There were no differences in adherence (P = 0.573) or differences in CD4 count and weight changes over time in the interventions.

CONCLUSIONS

Good adherence to ART is possible in resource constrained countries. Persistent adherence counseling in clinic settings by itself may be effective in improving adherence to ART.

Expression of cystic fibrosis transmembrane conductance regulator in the human distal lung

The determination of the expression of cystic fibrosis transmembrane conductance regulator (CFTR) in the lung is essential for a full understanding of the normal lung physiology and the pathogenesis of the lung disease in cystic fibrosis (CF). However, studies on the expression of CFTR in the distal adult human lung have yielded conflicting results despite functional evidence of expression of CFTR in bronchiolar and alveolar epithelial cells. We used 2 high-affinity monoclonal anti-CFTR antibodies, MAb24-1 and MAb13-1, to determine the expression of CFTR in samples of bronchiolar and alveolar tissues obtained from the same non-CF individuals. CFTR immunostaining was detected in the epithelium of bronchiolar and alveolar tissues. The staining pattern was similar with both antibodies. In bronchioles, CFTR labeling was present mostly in ciliated cells; in alveoli, CFTR labeling was detected in both type I and type II cells. We conclude that CFTR is expressed in human bronchiolar and alveolar epithelial cells. The potential importance of CFTR expression in alveoli should be further investigated, particularly with respect to the CF lung disease and the physiology of the alveolar region.

Echocardiographic patterns of juvenile rheumatic heart disease at the Kenyatta National Hospital, Nairobi

OBJECTIVE

To describe the echocardiographic features of children with rheumatic heart disease seen at the Kenyatta National Hospital.

DESIGN

A retrospective study.

SETTING

The Kenyatta National Hospital Heart Unit.

SUBJECTS

Patients aged 20 years and less with echocardiographic diagnosis of rheumatic heart disease.

RESULTS

Two hundred and twenty four echocardiograms were analysed. Seventy six point four of cases were aged between 5 and 15 years, while on 3% were less than five years. The combinations mitral and aortic regurgitation was the most common lesion followed by isolated mitral regurgitation. Isolated aortic regurgitation was as rare as isolated mitral stenosis in the paediatric age group 1.8% and 2.7% respectively. When seen in the younger age group, the leaflet morphology in mitral regurgitation was predominantly thickening and clubbing of the leaflets while in the older children the pathology was of marked fibrosis of the sub-valvular apparatus. Leaflet prolapse and commissural fusion was the major pathology in aortic regurgitation. Pulmonary hypertension was the most common complication commonly seen in mitral valve disease. Calcification was a rare encounter in this age bracket.

CONCLUSIONS

Rheumatic heart disease in the paediatric age commonly presents as isolated mitral regurgitation or in combinations of mitral and aortic regurgitation. The complications of pulmonary hypertension was predominant in mitral valve disease. Valvular calcification is rare in juvenile rheumatic heart disease.

Estimation of CD4 T-lymphocyte counts from percent CD4 T-lymphocyte determinations in HIV-1-infected subjects in sub-Saharan Africa

The relationship between CD4 percent and CD4 count has been reported to be different in industrialized countries compared to sub-Saharan Africa, where often only the former is reliable. CD4 determinations from an open cohort of hotel workers in Dar es Salaam followed between 1990 and 1998 were evaluated. T-lymphocyte determinations were offered once a year to 190 HIV-1 seropositive, 80 seroconverters and 495 sex and age matched HIV-seronegative subjects. After log transformation of the CD4 percent and CD4 counts a good fit to a linear regression curve was found, R(2) 0.697. The CD4 percent corresponding to a CD4 count of 200 cells/mm(3) was found to be 9.8%. CD4 percent determination can be useful to estimate CD4 counts, but needs to be locally standardized. The CD4 percent in Africa corresponding to AIDS defining CD4 counts seems to be lower than in the industrialized world.

Dropouts in a long-term follow-up study involving voluntary counseling and HIV testing: experience from a cohort of police officers in Dar Es Salaam, Tanzania

BACKGROUND

Results of most population-based studies primarily are derived from people who responded positively and thereby continued to participate in such studies. It is, however, equally important to know the characteristics of study subjects who drop out to learn the reasons that kept them from continuing to participate in the study, especially because they had initially agreed to participate in such a study. In studies with long-term follow-up, reasons for nonresponse may provide invaluable information that may be gathered through continued contact with study subjects who have withdrawn from the study.

OBJECTIVES

To determine characteristics of study participants who withdrew from an ongoing study of police officers, which involved counseling and HIV testing, and to determine reasons for their discontinued participation.

METHODS

Demographic characteristics of a cohort of police officers who had been participating in a study to determine their suitability for HIV vaccine trials were analyzed. Characteristics of those who did not return for the second survey of appointments for HIV testing were compared with those who continued their participation. A randomly selected sample of 132 police officers who did not participate in the second survey of HIV testing were asked why they did not return. Answers were obtained from 84 people who had discontinued their participation.

RESULTS

Of eligible police officers, 2087 (72.1%) responded to the call for follow-up appointments, whereas 807 (27.9%) did not return. Those who did not return to participate in the second survey had significantly higher rates of HIV seropositivity (17.2%) than those who did return (13.5%) (p <.05). The rate of return in unmarried participants was worse (p <.05) than the rate among married participants. Rates of sexual contacts with partners other than their spouses and levels of alcohol consumption did not differ between the two groups. Reasons for dropping out of the study included fear of knowing results of HIV testing in 54.6%, lack of time to continue in 34.5%, and fears about job security in 3.6%.

CONCLUSION

Fears of finding out that one might be seropositive need to be answered at recruitment, and practical arrangements must be made to facilitate further follow-up. A bias for lower incidence might be introduced in vaccine trials if participants thought to be at highest risk for HIV infection discontinue participation.

Isoniazid prophylaxis for tuberculosis prevention among HIV infected police officers in Dar es Salaam

OBJECTIVE

To determine the acceptability, compliance and side effects of isoniazid (INH) prophylaxis against tuberculosis among HIV infected police officers (PO) in Dar es Salaam.

DESIGN

A nested study from a prospective follow up of a cohort of police officers.

SETTING

Dar es Salaam, Tanzania.

SUBJECTS

One hundred and forty three HIV-1 infected police officers.

MAIN OUTCOME MEASURES

Acceptance and compliance to INH prophylaxis.

RESULTS

Of the 400 HIV-1 infected officers, 143 (35.7%) came forward for post-test counselling and HIV test results. Sixty per cent (87/143) of them accepted to be on INH prophylaxis. However only 42.5% (37/87) came forward for evaluation regarding their suitability for INH prophylaxis. During the evaluation, eight (21.6%) of 37 otherwise asymptomatic PO were found to have active pulmonary tuberculosis (TB). Eventually only 29 PO were actually started on INH, and only 16 (55.2%) of them completed the six months course. No serious side effects were observed. One PO developed TB two months after loss to follow up before completing the six months.

CONCLUSIONS

There was low acceptability of and poor compliance with INH prophylaxis among the HIV-1 infected PO despite being educated on the benefits of prophylaxis. The prevalence of PTB among asymptomatic HIV-1 infected PO was high, and therefore persons with HIV infection should be examined for TB even in the absence of symptoms.

The prevalence and incidence of HIV-1 infection and syphilis in a cohort of police officers in Dar es Salaam, Tanzania: a potential population for HIV vaccine trials

OBJECTIVES

To assess the suitability of a cohort of police officers in Dar es Salaam for HIV vaccine trials by determining the prevalence and incidence of HIV-1 infection, active syphilis and their associated factors.

DESIGN AND SETTING

An open cohort study of police officers in Dar es Salaam, Tanzania.

METHODS

Recruitment of police officers began in 1994. A standardized questionnaire was completed at enrolment and subsequent visits. HIV antibodies were determined using two consecutive enzyme-linked immunosorbent assays. Samples repeatedly discordant on the two tests were tested by a Western blot assay. Treponema pallidum antibodies were first determined by Venereal Disease Research Laboratory (VDRL) test and reactive sera were confirmed by Treponema pallidum hemagglutination test.

RESULTS

At the end of 1996 a total of 2850 police officers had been recruited of whom 2733 (96%) consented to be tested for HIV. The overall HIV-1 seroprevalence at recruitment was 13.8% (378 of 2733). Females had a significantly higher HIV-1 seroprevalence, 18.0% (55 of 306), as compared to males, 13.3% (323 of 2427), P< 0.05. From a total of 2215 married police officers, 585 (26.4%) responded to a question on extramarital sex within the previous 3 months of whom 36.2% (212 of 585) admitted to have had at least one extramarital sexual intercourse. Condoms were not used during these encounters by 178 of 212 (84.0%). As of 31st December 1998, among the 1524 males observed for 2553 person-years (PYAR), 50 had seroconverted and among 200 females observed for 357 PYAR, eight had seroconverted. The overall crude HIV-1 incidence was thus 19.9/1000 PYAR; 19.6 and 22.4/1000 PYAR for males and females, respectively. The overall prevalence and incidence of active syphilis were 3.1% (88 of 2850) and 8.6/1000 PYAR (26 of 3149), respectively. Males had a higher prevalence of active syphilis, 84 of 2525 (3.3%) than females, five of 325 (1.5%), P = 0.09.

CONCLUSIONS

There was high risk sexual practice including low condom use in this cohort of police officers. The incidence and prevalence of HIV infection were high. Police officers in Dar es Salaam are therefore a potential population group for HIV vaccine evaluation.

Diagnosis of tuberculosis in sputum negative patients in Dar es Salaam

OBJECTIVE

To determine diagnostic criteria for tuberculosis among sputum smear acid fast bacilli negative patients with chronic cough, based on symptoms, signs and simple laboratory tests.

DESIGN

A two-month prospective follow up study.

SETTING

Muhimbili Medical Centre, Dar es Salaam, Tanzania.

SUBJECTS

One hundred and seventy- eight consecutive patients admitted between 1st November, 1994 and 31st March, 1995 with chronic productive cough.

MAIN OUTCOME MEASURES

Sputum smear acid fast bacilli (AAFB) negative with TB, discriminating ability of clinical and laboratory parameters.

RESULTS

Forty three (24.2%) were sputum smear positive for acid fast bacilli (AAFB). In 90 (50.6%) patients, AAFB could be isolated in specimen other than sputum and in 45 (25.3%) no AAFB could be isolated. In a univariate analysis of all symptoms, signs and laboratory test results, cough of four or more weeks, haemoptysis, oral candidiasis, chest consolidation, pleural effusion, mid zone and upper zone chest x-ray opacities were significantly different between sputum AAFB negative TB and non TB patients. Discriminant analysis revealed six highly significant variables: Mantoux reaction, pleural effusion, Kaposi's lesion, cervical lymphadenopathy, matted lymph node, mid zone and upper zone CXR infiltrates. From these variables an equation was derived to calculate the probability that a sputum smear negative patient had tuberculosis. Then a scoring system was developed that classified correctly 84% of cases of sputum AAFB negative patients into tuberculosis or non tuberculosis.

CONCLUSION

In sputum smear AAFB negative patient clinically suspected to have tuberculosis, Mantoux reaction, cervical lymphadenopathy, matted lymph nodes, absence of mid lower zone infiltration on CXR and presence of pleural effusion could be used for presumptive diagnosis, but they would not make a therapeutic trial unnecessary.

Survival time of patients with acquired immune deficiency syndrome: experience with 274 patients in Dar-es-Salaam

To determine the survival time once acquired immune deficiency syndrome (AIDS) has developed, we analysed case records of 274 patients confirmed to have died of the disease. Of the 274 patients 193 were males and 81 females (M:F 2:1). The duration of symptoms ranged from a few weeks to two years but over 70% had apparently enjoyed good health until 2-3 months before diagnosis. Weight loss, severe weakness, chronic diarrhoea, prolonged fevers and oro-pharyngeal candidosis were the commonest features. Kaposi's sarcoma (KS) was the presenting feature in 2 (0.7%) patients. Frequent concurrent illnesses included tuberculosis (19%), unspecified (23%) and skin lesions other than KS (24%). In 31 (11.3%) patients no concurrent illness was detected. The survival after one week was 63.5% and 7.5% at the end of three months. These results indicate that due to a combination of factors survival of AIDS patients in developing countries is much shorter than in developed countries.