Management of Renal Disease: utility of a joint HIV-renal clinic

Abstract

Although there has been a decrease in the incidence of HIV-associated nephropathy, the incidence of chronic kidney disease (CKD) is increasing in patients attending HIV clinics. Traditional risk factors for CKD, including diabetes, hypertension and coinfection with hepatitis C virus, are overrepresented in this population, making it difficult to distinguish the contribution of HIV infection 1. HIV-infected patients are at risk of renal dysfunction caused by HIV and by antiretroviral treatment (ART) toxicity. In particular, tenofovir disoproxil fumarate (TDF) has been associated with proximal renal tubular dysfunction 2. In 2014 locally in Brighton we had a cohort of 2150 HIV-infected patients, 90% of whom were on ART with 910 of 1935 (47.0%) on regimens including TDF. In addition to using a written protocol for monitoring renal function in patients on antiretrovirals (ARVs) and a standardized operating policy for investigation of abnormal blood tests and urinalysis, we run a ‘one-stop shop’ HIV-renal specialist clinic with an HIV physician and renal physician working together seeing referrals from the general HIV clinic. This study aimed to investigate the utility of this clinic and to describe renal disease in this cohort. We reviewed all patient records of patients seen in a specialist HIV-renal clinic between 2012 and 2014. Demographics, HIV history, number of visits, the indication for referral and outcome information were collected using a standardized proforma. Sixty-five patients, with a median age of 51 years (28–88 years) and a median duration of HIV infection of 163 months (20–335 months), were seen. Forty-two were taking TDF for a mean of 55.8 months (9–122 months). A total of 42 of 65 patients were reviewed once with a median number of visits of 1 (1–4). There were 98 appointments, 54 of which were virtual. The did-not-attend (DNA) rate was 11.4%. Referred patients were categorized as having: proteinuria on TDF (38 of 65 patients; 59%), proteinuria not on TDF (12 of 65 patients; 18%) and raised creatinine without proteinuria (15 of 65 patients; 23%). Of the 38 patients on TDF with proteinuria, five (13.2%) had TDF toxicity diagnosed and TDF was discontinued immediately, and 27 continued with close monitoring with a further seven subsequently discontinuing; the total number discontinuing was 12 of 38 (32%). Addition or up-titration of medications for poorly controlled hypertension was the commonest intervention overall in the joint HIV-renal clinic (23 of 65 patients; 35.4%), in particular in the non-TDF proteinuria group (eight of 12 patients; 66.7%). Renal calculi were a frequent contributor to renal dysfunction and four of 65 patients (6%) had a new glomerular diagnosis after undergoing renal biopsy [two had focal segmental glomerulosclerosis, one had immunoglobulin A (IgA) nephropathy and one had glomerulonephritis with granulomata]. In four patients (6%), the creatinine rise was attributed to nonsteroidal anti-inflammatory drug (NSAID), creatine or protein supplement usage. TDF toxicity was the commonest reason for referral but only a minority of referred patients (13.2%) needed to discontinue immediately. Optimizing blood pressure control was the most frequent outcome, suggesting that this is an underappreciated priority among HIV physicians.