The clinical and pathological characteristics of Chinese elderly patients with anti-neutrophil cytoplasmic autoantibodies associated small vessel vasculitis

Abstract

Background: Anti-neutrophil cytoplasmic autoantibodies (ANCA) are serological markers of ANCA-associated small vessel vasculitis (AASV) which is one of common autoimmune diseases in Caucasian elderly population.

Objective: To analyze the clinical and pathological characteristics of Chinese elderly patients with AASV.

Methods: One-hundred forty one Chinese patients with AASV over 65 years old, diagnosed between 1997 and 2001 in the Institute of Nephrology of Peking University First Hospital, were retrospectively studied and their clinical and pathological data were analyzed.

Results: Patients diagnosed with AASV patient increased chronologically with the yearly ratio in 2000 and 2001 significantly (P < 0.05) higher than that in 1998 and before. Of the 141 patients, 72 were male and 69 were female with an average age of 68.2 years. 13 of the 141 were cytoplasmic ANCA (cANCA) positive and all recognized proteinase 3 (PR3). The other 128 were perinuclear ANCA (pANCA) positive and 120/128 recognized MPO, 8/128 recognized both PR3 and MPO. Less than 50% of the patients were correctly diagnosed within 3 months. Clinically, 78% of the patients had fever and fatigue, 52.5% had body weight loss, 96.4% had kidney involvement, of which 75% had elevated serum creatinine and 30.8% had acute renal failure. 76.6% had lung involvement, over half of them had hemoptysis or lung infiltrates. Other clinical manifestations included arthralgia (48.2%), muscle pain (39.7%), gastrointestinal symptoms (39.7%), eye involvement (28.3%) and ENT involvement (31.2%). In laboratory examinations, 94.4% of the patients had anemia, 62.4% had increased WBC count, 93.6% had increased ESR and 55.1% had increased CRP.

Conclusions: More and more patients with AASV were diagnosed in Chinese elderly. Kidney was the most vulnerable organ to be involved and lung was the most important extra-renal organ to be affected. For elderly patients with multi-organ damage, an ANCA test should be performed in order to make an early diagnosis and start therapy in time.