Renal Abnormalities in Leprosy

Abstract

We have evaluated laboratory and clinical manifestations of renal disease in 96 patients with leprosy, looking for a sensitive and early marker for detection and possibly follow-up of nephropathy in these patients. Microscopic hematuria was observed in 21.9% of the cases (with dysmorphic erythrocytes in 71.4% of them). Abnormal microalbuminuria and urinary β₂-microglobulin were found in 15.8 and 19.8% of the cases, respectively. We have observed a high frequency of hematuria, abnormal microalbuminuria and elevation of urinary β₂-microglobulin in these patients still with normal serum creatinine.

Renal involvement in leprosy: retrospective analysis of 461 cases in Brazil

“…The biopsy findings of these patients showed nephritis of all kinds in all patients, except in six who had no renal abnormality. Hematuria was a common finding in a study performed in patients from São Paulo, Brazil, where it was found in 21 of 96 patients [31]. Proteinuria was not frequent in these patients, being detected in only two, with one reaching nephrotic levels [31].…”

“…In a study performed by Kirsztajn et al [31], no obvious alteration of renal function was detected in the analysis of serum creatinine. These same authors proposed the dosing hematuria, microalbuminuria and ß 2 -microglobulin to detect the earliest alterations of renal involvement in leprosy [31]. Acute renal failure can occur in leprosy, the main cause of this being the occurrence of acute tubular necrosis as a result of sepsis observed in the end stages of the disease [7].…”

“…Hematuria was a common finding in a study performed in patients from São Paulo, Brazil, where it was found in 21 of 96 patients [31]. Proteinuria was not frequent in these patients, being detected in only two, with one reaching nephrotic levels [31]. The presence of these abnormalities in urinalysis suggests glomerular injury.…”

“…Leprosy patients with renal injury have a large spectrum of clinical manifestations, which range from asymptomatic disease to classical nephrotic syndrome [7]. In a study performed by Kirsztajn et al [31], no obvious alteration of renal function was detected in the analysis of serum creatinine. These same authors proposed the dosing hematuria, microalbuminuria and ß 2 -microglobulin to detect the earliest alterations of renal involvement in leprosy [31].…”

“…The exact pathogenesis of renal lesions in leprosy is still uncertain [18]. Glomerular lesions can be caused by immune-complexes, which develop during the reactional states, mainly in the erythema nodosum leprosum [20,31,32]. This conclusion is supported by clinical and laboratorial findings, such as visualization of immune complexes and a decrease of serum complement in some cases [5,7,[21][22][23][24][25].…”