1. Discussion and Conclusion
HIV treatment guideline changes: implications for predicting network restructuring needs and distribution of CD4 testing platforms to laboratories across South Africa
Naseem Cassim1,2, Lindi M. Coetzee1,2 and Deborah K. Glencross1,2
1National Health Laboratory Service (NHLS) National Priority Programme, Johannesburg, South Africa
2University of the Witwatersrand, Johannesburg, South Africa
ID:
Introduction
Results
In 2015/16, the National Health Laboratory Service (NHLS) provided 3.44 million CD4 tests through the integrated tiered service delivery model (ITSDM) that matches service demands with appropriate technology [1,2]. Services however need to be flexible to meet changing antiretroviral HIV/AIDS (ART) guidelines [5]. The aim of this study was to predict changes in flow cytometer platforms influenced by ART guideline changes and international treatment goals.
Methods
Historical CD4 test volumes for 2015/16 were extracted from the corporate data warehouse (CDW) to establish a base-case (scenario one) and three forecasted scenarios, applying secondary information obtained from NDOH HIV/AIDS fact sheet distributed at the 7th South Africa AIDS Conference, the 90/90/90 initiative targets and District Heath Information System (DHIS) reported data [3,4]. Scenario-2 is based on the assumption that 90% of all HIV+ individuals receive CD4 testing. Scenario-3 assumed CD4 testing is offered only to ART-naïve individuals, while in scenario-4 CD4 testing is offered only to new patients being initiated on ART. The forecasted annual volumes for each scenario were used to project daily laboratory volumes to assign flow cytometry platforms. Daily laboratory volumes were calculated and categorized into tiers: (i) Tier-2, (ii) Tier-3, (iii) Tier-4 and (iv) >300 Tier-5. Platforms were allocated matching CD4 tiers based on predicted volumes of tests. Laboratories performing samples/day use the Aquios system, whilst metro-laboratories (>300 samples/ day) utilize the fully automated CellMek/MPL platform (both Beckman Coulter (Miami, FL) [1,2]. Although not currently used, field-laboratories performing tests/day could efficiently utilise point-of-care (POC) CD4 technologies to meet low-end service needs at the Tier-2 level, i.e. FacsPresto (Becton Dickinson, Franklin Lakes, NJ) [1,2].
Figure 1: Logic diagram illustrating data sources and assumptions used to generated CD4 test volumes across our scenarios
In 2015/16, 3.4 million CD4 samples were performed within the NHLS network (Scenario One). This decreases to 2.56 million and 678 thousand in scenario’s three and four respectively. Scenario two increases CD4 volumes significantly to 5.67 million.
Discussion and Conclusion
Figure 2: Allocation of testing platforms to laboratories using pre-defined daily thresholds
In the base-case, eight laboratories were re-assigned as Tier-2 field-laboratories using a POC platform, with 10 laboratories allocated the Aquios platform and 32 the CellMek/MPL platform. For Scenario-2, 35 and 12 laboratories were allocated to the Aquios and MPL/CellMek platforms respectively with no POC. In Scenario-3 and Scenario-4, the Aquios system is allocated to 14 and 26 laboratories respectively. The POC platform was allocated to 25 laboratories in Scenario-4, decreasing to 10 and 5 for Scenario-2 and Scenario-3 respectively.
Dramatic changes in annual CD4 volumes will result in platform changes at multiple laboratories from the base case scenario. This will require CD4 platform restructuring to align testing demands and capacity requirements. This would also necessitate staff re-training, competency assessment, instrument verifications and new laboratory information system (LIS) interface development. Switching CD4 platforms at a laboratory requires close national coordination.
References
Glencross DK, Cassim N, Coetzee LM, editors. Strategies for Full CD4 Services in South Africa using the Integrated Tiered Service Delivery Model (ITSDM). 7th SA AIDS Conference; 2015.
Glencross DK, Coetzee LM, Cassim N. An integrated tiered service framework based on testing demands can ensure accessible, scalable and affordable CD4 services across a national programme, in laboratories and at the point of care. PloS one
National Department of Health (NDOH). HIV & AIDS 2014/15 Data Fact Sheet. 7th South African AIDS Conference; Durban/South Africa2015.
Joint United Nations Programme on HIV/AIDS (UNAIDS) : An ambitious treatment target to help end the AIDS epidemic 2014 [Available from:
National Department of Health. National Consolidated Guidelines for the Prevention of Mother-to-Child Transmission of HIV (PMTCT) and the Management of HIV in Children, Adolescents, and Adults. Pretoria, South Africa: Government of South Africa; 2015.
Figure 3: Allocation of test volumes to flow cytometry platforms using pre-defined daily thresholds
In the base case, 92% of CD4 volumes were allocated to the Cellmek/MPL platform. This increases to 93% in Scenario-2 due to higher annual volumes. CD4 testing is offered using the Aquois platform in 13% and 76% for Scenario’s 3 and 4 respectively. In scenario-4, 18% of testing with be offered using the Presto platform.
Acknowledgements
We would like to acknowledge Kathryn Schnippel, Sithembile Mojalefa, Neo Mokone, Sherry Drury and the CDW for providing the required data.
DISCLAIMER: the opinions expressed here are those of the authors and not necessarily that of the NHLS