Urine erythrocyte morphology in patients with microscopic haematuria caused by a glomerulopathy

Abstract

The evaluation of urinary erythrocyte morphology (UEM) has been proposed for patients with isolated microscopic haematuria (IMH) to early orientate the diagnosis towards a glomerular or a nonglomerular disease. However, to date, the role of this test in patients with IMH has very rarely been investigated. Sixteen patients (ten children, six adults) with persistent IMH classified as glomerular on the basis of repeated UEM evaluations (55 urine samples, two to eight per patient) were submitted to renal biopsy. This showed a glomerular disease in 14/16 patients (87.5%) (nine thin basement membrane disease; three Alport syndrome; two other), whereas in two patients, no abnormalities were found. Of four microscopic criteria investigated to define a IMH as glomerular, >80% dysmorphic erythrocytes were not found in any sample, >or=40% dysmorphic erythrocytes alone were seen in seven samples (12.7%), >or=5% acanthocytes alone in 15 samples (27.3%) and erythrocytic casts in six samples (10.9%). There was >or=40% dysmorphic erythrocytes associated with >or=5% acanthocytes in 25 samples (45.5%). Sensitivity and positive predictive values in diagnosing a glomerular haematuria were 59.2% and 90.6%, respectively, for >or=40% dysmorphic erythrocytes, 69.4% and 85% for >or=5% acanthocytes/G1 cells and 12.2% and 100% for erythrocytic casts. Our findings demonstrate that the evaluation of UEM is useful to identify patients with an IMH of glomerular origin.

The role of molecular genetics in diagnosing familial hematuria(s)

“…It has been reported that the frequency of MH can be as high as 1%, although different reports have mentioned frequencies as high as 20% of the general population [1]. It is unknown what portion of MH in the general population is of hereditary nature.…”

Diagnostic Value of Urinary Dysmorphic Erythrocytes in Clinical Practice

“…Although dipstick testing is easy to perform in general practice, the morphology of urinary red blood cells (RBC) has been advocated as a fine diagnostic tool to differentiate between glomerular and nonglomerular causes of hematuria [6,7,8]. In glomerular hematuria, the variation in size and shape of the urinary RBC is increased, and such RBC are generally called dysmorphic RBC (dRBC).…”

Non-nephronal hematuria misdiagnosed as C1q nephropathy: Look before you leap

“…Distinctive features of glomerular hematuria include red cell casts, protein excretion exceeding 500 mg/day at a time when there is no gross bleeding, a dysmorphic appearance of most (>80%) red cells (particularly if >5% acanthocytes), brown to cola-colored urine with gross hematuria and lower mean corpuscular volume (MCV) of RBC based on coulter analysis of urine. [3–5] Although helpful if present, the absence of these findings does not exclude glomerular disease. When persistent hematuria is essentially the only manifestation of glomerular disease, one of three disorders is most likely namely Ig-A nephropathy, Alport syndrome, and thin basement membrane nephropathy (gross hematuria unusual).…”