Our data showed a female predominance among the patients. Eleven patients had involvement of more than one organ. Renal involvement was the most common manifestation. Fourteen patients underwent renal biopsy. Four patients had focal proliferative
glomerulonephritis with crescent formation. Two had necrotizing
glomerulonephritis with crescent formation. Two patients had minor glomerular abnormalities, 2 had
IgA nephropathy, one had
membranous nephropathy, one had focal proliferative
glomerulonephritis, one had granulomatous
interstitial nephritis, and the remaining one had focal segmental glomerular
sclerosis.
Immune complex glomerulonephritis was found in 3 patients. On indirect immunofluorescence, 17 patients were perinuclear-pattern
ANCA-positive, one was positive for atypical
ANCA, and one was positive for cytoplasmic-pattern-
ANCA. By ELISA, 4 patients were positive for both
myeloperoxidase (MPO)-
ANCA and proteinase-3 (PR3)-ANCA, one was positive for PR3-ANCA only, and the others were positive for MPO-
ANCA only. For the treatment of
vasculitis, 5 patients received
prednisone alone, 10 received
prednisone and
cyclophosphamide, and the remaining 4 did not receive
prednisone or
cyclophosphamide. During followup, 15 patients achieved remission, 3 patients died, and one patient depended on dialysis. In general, MPO-
ANCA concentration did not correlate with
disease progression, and a delayed decrease of MPO-
ANCA concentration was found in most patients who achieved remission.
CONCLUSION: Most patients with PTU-associated
ANCA-positive
vasculitis had good outcomes; however, severe cases existed. We suggest early recognition and adequate treatment are necessary to improve outcome.