[IgA nephropathy with crescentic glomerulonephritis and ANCA positive]

We present a case of IgA nephropathy diagnosed by renal biopsy that presents after 2 years of folow-up an impairment of the renal function associate histoligically to a crescentic glomerulonephritis. The immunologic determinations showed of high titers of antineutrophil cytoplamic antibodies (ANCA) (P-ANCA IgG antiMPO and P-ANCA IgA anti-MPO). The patient began treatment with haemodyalisis and one year later she received a cadaveric kidney transplantation with good result. Two years later she had normal urine sediment, negative proteinuria, normal renal function but high titers of IgG and IgA PANCA anti-MPO. In summary, we believe that the determination ANCA in acute renal failure due to IgA nephropathy can indicate the existence of a IgA crescentic glomerulonephritis superimposed or an associated small vessel vasculitis and it confers a worse prognosis. The positive maintenance of IgG P-ANCA anti-MPO IgG anti-MPO titers during the course suggests that the sequential determination of ANCA in this entity is not useful to the monitoring of the clinical activity.