Urinalysis Findings in IgA Vasculitis

Red Blood Cell Morphology

Dysmorphic RBCs are the hallmark finding in IgA vasculitis with renal involvement, indicating glomerular bleeding, according to the American Academy of Family Physicians 2
Red cell casts are virtually pathognomonic for glomerular bleeding, though they are relatively insensitive markers and may not always be present, as noted by the American Academy of Family Physicians 2
Accurate determination of RBC morphology requires inverted phase contrast microscopy for optimal visualization, as recommended by the American Academy of Family Physicians 2

Moderate proteinuria (1-3 g/day) is typical in IgA vasculitis with renal involvement, as reported in Kidney International 1
Significant proteinuria is defined as total protein excretion greater than 1,000 mg per 24 hours, which should prompt thorough evaluation or nephrology referral, according to the American Academy of Family Physicians 2
Microscopic hematuria is the most common finding, often accompanied by dysmorphic RBCs and red cell casts, as noted in Kidney International 1
Urine dipstick will be positive for blood in the setting of glomerular hematuria, as reported in Kidney International 4

While hematuria and proteinuria are present during active disease and can resolve completely, their persistence does not necessarily imply ongoing active disease, as noted in Kidney International 4
The presence of significant proteinuria (>1,000 mg/24 hours), red cell casts, renal insufficiency, or predominance of dysmorphic RBCs should prompt evaluation for renal parenchymal disease or nephrology referral, according to the American Academy of Family Physicians 2