[A study of serum and urinary immunoglobulins after forced lordosis].
We described transient low or non selective proteinuria after forced lordosis was as a characteristic of orthostatic proteinuria and the decrease in the urinary IgA/IgG ratio after lordosis was useful in confirming the diagnosis of the disease. In this study we examined the urinary excretion of IgG, IgA and IgG4, an anionic immunoglobulin, after forced lordosis in 44 orthostatic proteinuria children (group OA) and 24 chronic glomerulonephritis patient in stable stage (group GN). Urinary IgG4/IgG after lordosis was not significantly different between groups OA and GN. It showed that urinary IgG4/IgG ratio was not so useful in the differential diagnosis of this disease. In group OA, urinary IgA/IgG correlated significantly with serum IgA/IgG (y = 0.35X + 7.0, r = 0.354, p less than 0.05), and urinary IgG4/IgG also correlated significantly with serum IgG4/IgG (y = 1.22x + 0.14, r = 0.813, p less than 0.001). From these results it is suggested that proteinuria after forced lordosis in children with orthostatic proteinuria is composed of a transient low or non selective proteinuria in terms of both size and charge of protein. It seems more likely that the so-called heteroporous theory and sieving function theory explain the mechanism of orthostatic proteinuria.
Mihata
M
M
Department of Pediatrics, Hyogo College of Medicine, Japan.
D000293:Adolescent; D002648:Child; D005260:Female; D005921:Glomerulonephritis / Q000378:metabolism; D006801:Humans; D007070:Immunoglobulin A / Q000032:analysis; D007074:Immunoglobulin G / Q000032:analysis; D007136:Immunoglobulins / Q000032:analysis* / Q000652:urine; D008297:Male; D011187:Posture; D011507:Proteinuria / Q000378:metabolism
D007070:Immunoglobulin A; D007074:Immunoglobulin G; D007136:Immunoglobulins