[Is immediate allergy the source of hematuria in children]

The authors report 2 cases of children presenting with episodes of hematuria, frequently following attacks of asthma or of allergic rhinitis. In both children, a respiratory provocation test with a mite extract triggered off hematuria. One child had an IgA nephropathy. In the second, the renal biopsy was normal and the cause of the hematuria remains unknown. These case reports suggest the need to carry out a systematic search for microscopic hematuria in patients with asthma.