The CALVIH Study: How to Handle Renal Stones in Persons Living with HIV₁?

Background: Renal stone (RS) is a highly prevalent disease in our societies and is mostly secondary to lifestyle habits. HIV1 patients often experience RS, although specific risk factors are not known. Despite other priorities, comprehensive work-up should be offered to avoid recurrences (50% risk in 5 years). Purpose and Methods: The aim of the study is to describe how to handle RS in persons living with HIV1 and to suggest how the understanding of mechanisms involved in stone composition helps customize therapy and prevent recurrences. We prospectively performed a complete work-up in a cohort of 23 prevalent HIV1 patients referred to our highly-specialized center by HIV physicians. Results: Inclusion was secondary to a colic episode with spontaneous elimination of the stone (74%), bilateral (67%), not obstructive (67%);53% underwent urologic interventions. Mean age was 34 ± 16 years old and BMI was 22.5 ± 3 (one-third with metabolic syndrome). History of RS showed only one episode (22%), >one (74%) or >4 (4%). Estimated GFR was 78 ± 24 ml/min/1.73m2 (mean Cr 101 ± 24 μmol/L), and 5 were classified CKD stage 3. Stone analysis was only available for 7 patients and in 6/7 patients, and calcium metabolism was fully explored (2 absorptive hypercalciuria, 4 renal primitive hypercalciuria). Retained mechanism for RS was uric acid dependent for one, oxalic acid dependent for three and calcium dependent for three. Very few patients were exposed to known environmental risk factors for RS, 3 were/had been exposed to darunavir and 3 to atazanavir, 1 to efavirenz, 1 to acetazolamide, 2 to allopurinol. Conclusion: RS in HIV1 patients is mostly not related to ARV. Understanding of renal stone composition is critical to prevent recurrences by offering specific dietetic counselling and therapy. The role of HIV physicians is important due to the high prevalence of RS in the context of HIV disease.