Clinical illness as a marker for initiation of HIV antiretroviral therapy in a rural setting, Rakai, Uganda

A Quality Management Approach to Implementing Point-of-Care Technologies for HIV Diagnosis and Monitoring in Sub-Saharan Africa

Technology advances in rapid diagnosis and clinical monitoring of human immunodeficiency virus (HIV) infection have been made in recent years, greatly benefiting those at risk of HIV infection, those needing care and treatment, and those on antiretroviral (ART) therapy in sub-Saharan Africa. However, resource-limited, geographically remote, and harsh climate regions lack uniform access to these technologies. HIV rapid diagnostic tests (RDTs) and monitoring tools, such as those for CD4 counts, as well as tests for coinfections, are being developed and have great promise in these settings to aid in patient care. Here we explore the advances in point-of-care (POC) technology in the era where portable devices are bringing the laboratory to the patient. Quality management approaches will be imperative for the successful implementation of POC testing in endemic settings to improve patient care.

HIV/AIDS Clinical Manifestations and their Implication for Patient Clinical Staging in Resource Limited Settings in Tanzania

BACKGROUND

Tanzania HIV/AIDS management follows WHO clinical staging which requires CD4 counts as complement. Lacking CD4 counts facilities in rural health facilities remains a challenge. Simplified and sensitive clinical staging based on local clinical patterns is useful to ensure effective care without CD4 counts.

OBJECTIVES

To assess whether local HIV clinical manifestations can be used to guide HIV management in settings with limited access to CD4 counts in Tanzania.

METHODS

A Cross-sectional study conducted at Tumbi and Chalinze health facilities documented clinical manifestations and CD4 counts in 360 HIV/AIDS patients. Simplified management groups comprised of severe and moderate disease were formed based on clinical manifestations and CD4 counts results. Symptoms with high frequency were used to predict severe disease.

RESULTS

A Weight loss (48.3%) and chronic cough (40.8 %) were the most reported manifestations in the study population. More than 50% of patients presented with CD4≤200. Most symptoms were found to be highly sensitive (71% to 93%) in predicting severe immunosuppression using CD4<200 cut-off point as a 'Gold standard'. Chronic diarrhoea presented in 10.6%, and predicted well severe immunosuppression either alone (OR 1.95, 95%CI, 0.95-4.22) or in combination (OR 4.21, 95%CI 0.92-19.33) with other symptoms. Basing strictly on WHO clinical staging 30.8% of patients were detected to be severely immunosuppressed (Stage 4). While using our proposed management categories of severe and moderate immunosuppression 70% of patients were put into the severe immunosuppression group, consistent with CD4 cut-off count of≤350.

CONCLUSIONS

HIV/AIDS clinics managing large cohorts should develop validated site specific guidelines based on local experiences. Simplified guidelines are useful for resource constrained settings without CD4 counting facilities.

T-cell enumeration from dried blood spots by quantifying rearranged T-cell receptor-beta genes

Significant hurdles remain to large-scale implementation of medical interventions in the developing world due to the lack of a modern diagnostic infrastructure. This is especially pertinent to the international roll-out of antiretroviral drugs to treat HIV, which ideally includes a CD4 T-cell count to determine eligibility. We designed a novel technique to estimate mature T-cell numbers by calculating the amount of rearranged T-cell receptor beta genes from dried blood spots of HIV-infected individuals in the United States and Uganda. It was observed that the rearranged T-cell receptor beta count correlated well with total lymphocyte counts from both study populations (Baltimore R=0.602, Uganda R=0.497; p<0.001) and the ability for this measurement to determine antiretroviral initiation was similar to total lymphocyte counts, which can be used to determine eligibility in HIV+children. This technique as well as other dried blood spot based technologies could increase the diagnostic and monitoring capabilities in resource-limited settings.

Estimating the capacity for ART provision in Tanzania with the use of data on staff productivity and patient losses

BACKGROUND

International targets for access to antiretroviral therapy (ART) have over-estimated the capacity of health systems in low-income countries in Sub-Saharan Africa. The WHO target for number on treatment by end 2005 for Tanzania was 10 times higher than actually achieved. The target of the national Care and Treatment Plan (CTP) was also not reached. We aimed at estimating the capacity for ART provision and created five scenarios for ART production given existing resource limitations.

METHODS

A situation analysis including scrutiny of staff factors, such as available data on staff and patient factors including access to ART and patient losses, made us conclude that the lack of clinical staff is the main limiting factor for ART scale-up, assuming that sufficient drugs and supplies are provided by donors. We created a simple formula to estimate the number of patients on ART based on availability and productivity of clinical staff, time needed to initiate vs maintain a patient on ART and patient losses using five different scenarios with varying levels of these parameters.

FINDINGS

Our scenario assuming medium productivity (40% higher than that observed in 2002) and medium loss of patients (20% in addition to 15% first-year mortality) coincides with the actual reported number of patients initiated on ART up to 2008, but is considerably below the national CTP target of 90% coverage for 2009, corresponding to 420,000 on ART and 710,000 life-years saved (LY's). Our analysis suggests that a coverage of 40% or 175,000 on treatment and 350,000 LY's saved is more achievable.

CONCLUSION

A comparison of our scenario estimations and actual output 2006-2008 indicates that a simple user-friendly dynamic model can estimate the capacity for ART scale-up in resource-poor settings based on identification of a limiting staff factor and information on availability of this staff and patient losses. Thus, it is possible to set more achievable targets.

Use of WHO clinical stage for assessing patient eligibility to antiretroviral therapy in a routine health service setting in Jinja, Uganda

In a routine service delivery setting in Uganda, we assessed the ability of the WHO clinical stage to accurately identify HIV-infected patients in whom antiretroviral therapy should be started. Among 4302 subjects screened for ART, the sensitivity and specificity (95% CI) of WHO stage III, IV against a CD4 count < 200 x 106/l were 52% (50, 54%) and 68% (66, 70%) respectively. Plasma viral load was tested in a subset of 1453 subjects in whom ART was initiated. Among 938 subjects with plasma viral load of 100,000 copies or more, 391 (42%, 95% CI 39, 45%) were at WHO stage I or II. In this setting, a large number of individuals could have been denied access to antiretroviral therapy if eligibility to ART was assessed on the basis of WHO clinical stage. There is an urgent need for greater CD4 count testing and evaluation of the utility of plasma viral load prior to initiation of ART to accompany the roll-out of ART.