Prevalence of clinical, immunological and irological failure among children on Haart at the university teaching hospital, Lusaka, Zambia

Abstract

Background: There is increasing evidence that the current clinical and immunological monitoring tools are not sufficient to identify early enough patients who are failing on treatment. Development of resistance to the limited treatment options for children and premature switching are the dangers. The objective of this study was to review patient records to see how well WHO staging, CD4 profiles and viral load estimations relate in children on treatment at the University Teaching Hospital (UTH).
Methods: A retrospective chart review of all children aged between 0-19 years that started treatment between January 2004 and Dec 2010 was carried out at the UTH. Systematic sampling was done of every second child who received HAART for more than 24 weeks, with at least one viral load (VL) reading beyond 24 weeks of treatment. Six-monthly clinical (WHO staging) immunological (age- related CD4 count/%) and virological data were collected until last follow-up review or five years on treatment. The 2010 Zambian Pediatric Guidelines were used to gauge age-related clinical, immunological and virological failure (VL> 1,000).
Results: A total of 517 patient records were reviewed (table 1). Mean age at ART initiation was 7 years ((SD 4.7yrs). Mean time after ART initiation when first viral load test was done was 2.7 years (SD 1.5yrs). Of all the viral loads done, 64% (328) had a routine indication for patients on treatment nearing the 3 year mark (mean 2.7 years). In 40% of children the first viral load test result was above 1,000 after 24 weeks or more of treatment. A total of 482 patients had WHO staging done at the time first VL test was done. Of the 359 patients (table 2) with a clinical stage I/II (not severely immunosuppressed), 41% were failing virologically. On the other hand, 63% of the patients with clinical stage III/IV had a VL below 1,000. Table 3 shows that there were 509 patients who had an immunological staging done at the time first VL was done. Of the 106 patients who were failing immunologically, 28% were virologically well suppressed. On the other hand of the 403 who were immunologically doing fine, 32% were failing virologically.
Conclusions: Clinical staging and Immunological monitoring in children on ART does not accurately identify those that are failing. A push for routine, affordable virological testing is needed to identify treatment failures early to prevent development of ART resistance and to avoid premature switches to second line in those who are actually well suppressed.