Clinician compliance with laboratory monitoring and prescribing guidelines in HIV-1-infected patients receiving tenofovir

S Afr Med J. 2016 Mar 9;106(4):52-3. doi: 10.7196/SAMJ.2016.v106i4.10153.

Abstract

Background: Tenofovir is part of the preferred first-line regimen for HIV-infected patients in South Africa (SA), but is associated with kidney toxicity. SA antiretroviral therapy (ART) guidelines recommend creatinine monitoring at baseline (ART start) and at 3, 6 and 12 months, and substituting tenofovir with zidovudine, stavudine or abacavir should creatinine clearance (CrCl) decrease to <50 mL/min.

Objective: To assess clinician compliance with tenofovir monitoring and prescribing guidelines.

Methods: We described the proportion of adult patients on tenofovir-based first-line ART who were screened for baseline renal impairment, were monitored according to the SA antiretroviral treatment guidelines, and were switched from tenofovir if renal function declined.

Results: We included 13 168 patients who started ART from 2010 to 2012. Creatinine concentrations were recorded in 11 712 (88.9%) patients on tenofovir at baseline, 9 135/11 657 (78.4%) at 3 months, 5 426/10 554 (51.4%) at 6 months, and 5 949/ 8 421 (70.6%) at 12 months. At baseline, 227 (1.9%) started tenofovir despite a CrCl <50 mL/min. While on tenofovir, 525 patients had at least one CrCl of <50 mL/min. Of 382 patients with ≥3 months' follow-up after a CrCl <50 mL/min, 114 (29.8%) stopped tenofovir within 3 months. Clinicians were more likely to stop tenofovir in patients with lower CrCl and CD4 count. Of 226 patients who continued to receive tenofovir and had further CrCls available, 156 (69.0%) had a CrCl ≥50 mL/min at their next visit.

Conclusions: Creatinine monitoring is feasible where access to laboratory services is good. Kidney function recovered in most patients who continued to receive tenofovir despite a CrCl <50 mL/min. Further research is needed to determine how best to monitor renal function with tenofovir in resource-limited settings.