Claudia Wallrauch

HIV incidence in rural South Africa: comparison of estimates from longitudinal surveillance and cross-sectional cBED assay testing.

Background The BED IgG-Capture Enzyme Immunoassay (cBED assay), a test of recent HIV infection, has been used to estimate HIV incidence in cross-sectional HIV surveys. However, there has been concern that the assay overestimates HIV incidence to an unknown extent because it falsely classifies some individuals with non-recent HIV infections as recently infected. We used data from a longitudinal HIV surveillance in rural South Africa to measure the fraction of people with non-recent HIV infection who are falsely classified as recently HIV-infected by the cBED assay (the long-term false-positive ratio (FPR)) and compared cBED assay-based HIV incidence estimates to longitudinally measured HIV incidence. Methodology/Principal Findings We measured the long-term FPR in individuals with two positive HIV tests (in the HIV surveillance, 2003–2006) more than 306 days apart (sample size n = 1,065). We implemented four different formulae to calculate HIV incidence using cBED assay testing (n = 11,755) and obtained confidence intervals (CIs) by directly calculating the central 95th percentile of incidence values. We observed 4,869 individuals over 7,685 person-years for longitudinal HIV incidence estimation. The long-term FPR was 0.0169 (95% CI 0.0100–0.0266). Using this FPR, the cross-sectional cBED-based HIV incidence estimates (per 100 people per year) varied between 3.03 (95% CI 2.44–3.63) and 3.19 (95% CI 2.57–3.82), depending on the incidence formula. Using a long-term FPR of 0.0560 based on previous studies, HIV incidence estimates varied between 0.65 (95% CI 0.00–1.32) and 0.71 (95% CI 0.00–1.43). The longitudinally measured HIV incidence was 3.09 per 100 people per year (95% CI 2.69–3.52), after adjustment to the sex-age distribution of the sample used in cBED assay-based estimation. Conclusions/Significance In a rural community in South Africa with high HIV prevalence, the long-term FPR of the cBED assay is substantially lower than previous estimates. The cBED assay performs well in HIV incidence estimation if the locally measured long-term FPR is used, but significantly underestimates incidence when a FPR estimate based on previous studies in other settings is used.

HIV prevalence and incidence in people 50 years and older in rural South Africa

To the Editor: Studies of HIV prevalence in sub-Saharan Africa usually focus on the age group 15 - 49 years. However, estimates of HIV prevalence in older people are required for health policy and planning. The health care and social needs of older HIV-infected individuals differ from younger people; e.g. because of different co-morbidities, different responses to antiretroviral treatment (ART), and the central role of older adults in African households. In South Africa, a nationally representative survey provided first insights into the burden of HIV in the population ≥ 50 years of age, reporting HIV prevalence in men/women as 10.4%/10.2% (in the age group 50 - 54 years), 6.2%/7.7% (55 - 59 years), and 3.5%/1.8% (≥ 60 years). However, the South African HIV epidemic is highly heterogeneous6 with substantial variation by geographic location and ethnic group, limiting the value of national averages.

Short course for focused assessment with sonography for human immunodeficiency virus/tuberculosis: preliminary results in a rural setting in South Africa with high prevalence of human immunodeficiency virus and tuberculosis.

In Africa, human immunodeficiency virus (HIV)–associated extrapulmonary tuberculosis (TB) is common and poses diagnostic difficulties. Ultrasound is useful to find suggestive signs such as effusions or abdominal lymphadenopathy. Because trained radiologists are scarce in resource-poor settings, even this simple and relatively inexpensive diagnostic tool is frequently unavailable to patients in district hospitals in sub-Saharan Africa. We developed a focused protocol for assessment with sonography for HIV/TB and trained physicians in a rural district hospital in South Africa. In this pilot study, high levels of confidence in identifying specific signs were rapidly achieved and ultrasound was introduced into routine clinical practice.

Abdominal tuberculosis: sonographic diagnosis and treatment response in HIV-positive adults in rural South Africa.

Summary Objective To investigate the diagnostic value of abdominal ultrasound in HIV-positive inpatients in a rural African setting. Methods This was a prospective case series over 3 months of adult HIV-positive patients with symptoms suggestive of abdominal tuberculosis (TB). Diagnostic ultrasound was performed for all patients: sonographic criteria included abdominal lymph node enlargement (>1.5 cm) and focal splenic lesions; ascites was a supportive finding. Further diagnostic studies, e.g., aspiration or biopsy were not routinely performed. TB treatment was initiated on the basis of clinical and sonographic features. The patients were contacted after 4 months to evaluate the clinical outcome. Results One hundred and eighty adult HIV-positive patients were screened; 30 (16.7%) showed sonographic signs of abdominal TB. The median CD4 count was 78 cells/mm3. Presenting symptoms were weight loss (86.7%), abdominal pain (76.7%), and diarrhea (60%). Abdominal lymph node enlargement was the diagnostic finding in almost all cases (96.7%); hypoechoic lesions of the spleen were seen in 50% and ascites in 73.3%. Follow-up information was available for 25 patients: 24% had died and the remaining 76% reported symptomatic improvement and weight gain. Conclusions Characteristic sonographic features of abdominal TB are common in HIV-infected inpatients in a rural African setting. Ultrasound should be introduced into clinical algorithms for the diagnosis of extrapulmonary TB.

Focused assessment with sonography for HIV-associated tuberculosis (FASH): a short protocol and a pictorial review

BackgroundUltrasound can rapidly identify abnormal signs, which in high prevalence settings, are highly suggestive of extra-pulmonary tuberculosis (EPTB). Unfortunately experienced sonographers are often scarce in these settings.MethodsA protocol for focused assessment with sonography for HIV-associated tuberculosis (FASH) which can be used by physicians who are relatively inexperienced in ultrasound was developed.ResultsThe technique as well as normal and pathological findings are described and the diagnostic and possible therapeutic reasoning explained. The protocol is intended for settings where the prevalence of HIV/TB co-infected patients is high.ConclusionFASH is suitable for more rapid identification of EPTB even at the peripheral hospital level where other imaging modalities are scarce and most of the HIV and TB care will be delivered in the future.

Diagnostic value of FASH ultrasound and chest X-ray in HIV-co-infected patients with abdominal tuberculosis.

In human immunodeficiency virus (HIV) co-infected tuberculosis (TB) patients with negative acid-fast bacilli smears, chest radiography (CXR) is usually the first imaging step in the diagnostic work-up. Ultrasound, also in the form of focused assessment with sonography for TB-HIV (FASH), is an additional imaging modality used to diagnose extra-pulmonary TB (EPTB). Findings from 82 patients with abdominal TB diagnosed by ultrasound were analysed and compared with CXR results. Enlarged abdominal lymph nodes were seen in 75.6% of the patients, spleen abscesses in 41.2% and liver lesions in 30.6%. CXR showed a miliary pattern in 21.9% of the patients; 26.8% of the CXR had no radiological changes suggestive of pulmonary TB. This patient group would benefit from ultrasound in diagnostic algorithms for HIV-associated EPTB.In human immunodeficiency virus (HIV) co-infected tuberculosis (TB) patients with negative acid-fast bacilli smears, chest radiography (CXR) is usually the first imaging step in the diagnostic work-up. Ultrasound, also in the form of focused assessment with sonography for TB-HIV (FASH), is an additional imaging modality used to diagnose extra-pulmonary TB (EPTB). Findings from 82 patients with abdominal TB diagnosed by ultrasound were analysed and compared with CXR results. Enlarged abdominal lymph nodes were seen in 75.6% of the patients, spleen abscesses in 41.2% and liver lesions in 30.6%. CXR showed a miliary pattern in 21.9% of the patients; 26.8% of the CXR had no radiological changes suggestive of pulmonary TB. This patient group would benefit from ultrasound in diagnostic algorithms for HIV-associated EPTB.

High uptake of HIV testing for tuberculosis patients in an integrated primary health care HIV/TB programme in rural KwaZulu-Natal

Tuberculosis (TB) is the leading cause of morbidity and mortality in the HIV-infected African population. The need for improved integration of HIV and TB services was highlighted by the World Health Organization (WHO) several years ago, but implementation of recommendations has been slow. HIV testing for TB patients is the gateway for combined HIV and TB treatment, care and prevention yet, in 2007, only 37% of TB patients in the WHO African region were tested for HIV. While some countries reported testing rates above 75%, a testing rate of only 39% was reported in South Africa, the country with the largest burden of HIV/TB co-infection. We describe our efforts to ensure high HIV testing rates in TB patients via an integrated programme at primary health care level in rural KwaZulu-Natal.

Point-of-Care Ultrasound Assessment of Tropical Infectious Diseases—A Review of Applications and Perspectives

The development of good quality and affordable ultrasound machines has led to the establishment and implementation of numerous point-of-care ultrasound (POCUS) protocols in various medical disciplines. POCUS for major infectious diseases endemic in tropical regions has received less attention, despite its likely even more pronounced benefit for populations with limited access to imaging infrastructure. Focused assessment with sonography for HIV-associated TB (FASH) and echinococcosis (FASE) are the only two POCUS protocols for tropical infectious diseases, which have been formally investigated and which have been implemented in routine patient care today. This review collates the available evidence for FASH and FASE, and discusses sonographic experiences reported for urinary and intestinal schistosomiasis, lymphatic filariasis, viral hemorrhagic fevers, amebic liver abscess, and visceral leishmaniasis. Potential POCUS protocols are suggested and technical as well as training aspects in the context of resource-limited settings are reviewed. Using the focused approach for tropical infectious diseases will make ultrasound diagnosis available to patients who would otherwise have very limited or no access to medical imaging.

Tuberculosis pericarditis with cardiac tamponade: management in the resource-limited setting.

We report a case of human immunodeficiency virus–associated pericardial tuberculosis complicated by cardiac tamponade. Emergency management and subsequent therapeutic interventions are described and then discussed with particular focus on resource-limited settings. The paucity of evidence to support clinical decisions is emphasized and the need for well designed diagnostic and therapeutic studies is highlighted.

Chest ultrasonography in patients with HIV: a case series and review of the literature

IntroductionPulmonary disease is common in HIV-infected patients. Diagnostic means, however, are often scarce in areas where most HIV patients are living. Chest ultrasonography has recently evolved as a highly sensitive and specific imaging tool for diagnosing chest conditions such as pneumothorax, pneumonia and pulmonary edema in critically ill patients. This article addresses the issue of imaging and differentiating common pulmonary conditions in HIV-infected patients by chest ultrasonography.MethodsWe report chest ultrasound features of five different common pulmonary diseases in HIV-infected patients (bacterial pneumonia, Pneumocystis jirovecii pneumonia, tuberculosis, cytomegalovirus pneumonia and non-Hodgkin lymphoma) and review the respective literature.ConclusionsWe observed characteristic ultrasound patterns especially in Pneumocystis jirovecii pneumonia and pulmonary lymphoma. Further exploration of chest ultrasonography in HIV-infected patients appears promising and may translate into new diagnostic approaches for pulmonary conditions in patients living with HIV.