Acantocitúria no diagnóstico das hematúrias da nefropatia diabética, nefropatia hipertensiva e glomerulonefrites / Acanthocyturia in diagnose of hematuria of the diabeticnephropathy, hypertensive nephropathy, and glomerulonephritis

RESUMO

A presença de hematúria em pacientes diabéticos ou hipertensos sugere outra glomerulonefrite (GN) que não nefropatia diabética (ND) e nefropatia hipertensiva (NH) respectivamente. A biópsia renal seria indicada e realizada. A urinálise por microscopia de fase (MCF) permite diferençar a hematúria glomerular, definida como acantocitúria >5%, da hematúria não glomerular. Os autores admitiram a hipótese de que a acantocitúria é um achado raro na ND e NH, a qual sugere a presença de outra doença glomerular. Amostras de urina de 102 pacientes com o diagnóstico clínico de ND (n=18) e de NH (n-16), de pacientes com glomerulonefrite (n=25), comprovada por biópsia renal, e de um grupo controle (n=43) foram examinadas por MCF, buscando a presença de hematúria e acantocitúria. A hematúria glomerular foi prevalente na ND, NH e GN em relação ao grupo controle (p<0,05). Contudo, a acantocitúria >5% prevaleceu em somente 48% das GNs (p<0,05).

ABSTRACT

The presence of hematuria in diabetic and hypertensive patients has been thought to indicate other glomerulonephritides (GN) other than diabetic nephropathy (DN) or hypertensive nephropathy (HN). Renal biopsy should be obtained in such instances. Urinalysis by phase contrast microscopy (PCM) allows glomerular hematuria, which is defined as acanthocyturia >5%, to be differentiated from nonglomerular hematuria. The authors hypothesize that acanthocyturia is an uncommon finding in both DN and HN, its finding suggesting the presence of other glomerular disease. Urine samples of patients with a clinical diagnosis of DN (n=18) and of HN (n=16), of patients with biopsy-proven GN (n=25), and control subjects (n=43) were examined by PCM for the presence of hematuria and acanthocyturia. Glomerular hematuria was prevalent in DN, HN and GN relative to control subjects (p<0.05). However, acanthocyturia was prevalent only in GN (48%). In conclusion, acanthocyturia is uncommon in patients with clinically diagnosed DN and HN, but the finding of acanthocyturia >5% may be useful to differentiate DN and HN from other glomerular diseases.