Long-term follow-up of microscopic polyangiitis, 17-year experience at a single center.
BACKGROUND
Long-term prognoses of Wegener granulomatosis (WG) and Churg-Strauss syndrome (CSS) are known; however, few data exist on long-term prognoses for microscopic polyangiitis (MPA). Our aim was to analyse the prognoses of MPA.


METHODS
Cohort study with retrospective selection of patients. Twenty-two patients admitted to our Hospital (1990-2006) with biopsy-proven MPA were studied. The start date for entry into the study was the date of diagnosis. Statistical analysis was performed to look for prognostic factors for survival.


RESULTS
MPA patients were followed-up for a median of 78 (5-131) months. MPA patients were treated with cyclophosphamide (Cy) plus corticosteroid (Cs) (59%) or Cs alone (41%). Seven MPA patients died. Cumulative MPA patient survival at 1, 5, and 10 years were 85% (75-95%), 85% (75-95%), and 74% (60-88%) in those treated with Cy plus Cs and 50% (32-68%), 36% (14-58%), and 0% (0-30%) in those treated with Cs alone, respectively (P=0.04). Disease extent index <5 (P=0.02) and age <65 years (P=0.02) were associated with improved survival rates in MPA patients treated with Cy. Five MPA (23%) patients relapsed after a median of 54 months (35-93). No variables were related to relapses. Despite treatment, 11MPA (50%) patients developed end-stage renal disease after a median of 9 months (0-53).


CONCLUSIONS
Most MPA patients had life-threatening renal or lung involvement at diagnosis. Patients not treated with immunosuppressants had a poorer prognosis. The long-term prognosis of MPA patients who survived 6 months post diagnosis was good, although renal survival rates are low.
Servicio de Medicina Interna Virgen de la Vega, Hospital Universitario de Salamanca, Paseo de San Vicente, 58-182, 37007, Salamanca, Spain.
María
M
Borao-Cengotita-Bengoa
Luis
L
Corral-Gudino
Javier
J
Del Pino-Montes
Jose Luis
JL
Lerma-Márquez
D000305:Adrenal Cortex Hormones / Q000627:therapeutic use*; D000328:Adult; D000368:Aged; D015331:Cohort Studies; D003520:Cyclophosphamide / Q000627:therapeutic use*; D018450:Disease Progression; D004359:Drug Therapy, Combination; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D008297:Male; D055953:Microscopic Polyangiitis / Q000188:drug therapy* / Q000401:mortality*; D008875:Middle Aged; D011379:Prognosis; D012008:Recurrence; D012189:Retrospective Studies; D013030:Spain / Q000453:epidemiology; D013997:Time Factors
D000305:Adrenal Cortex Hormones; D007166:Immunosuppressive Agents; D003520:Cyclophosphamide