Allopurinol過敏症候群：南臺灣某醫學中心的經驗

Inpatients with Allopurinol Hypersensitivity Syndrome: Experiences At A Medical Center In Southern Taiwan

Allopurinol被認為是一個有效且安全的降尿酸禁物，但是偶爾仍然會產生嚴重的allpurinol過敏性症候群。分析本院二十二位診斷為al1purinol過敏性症候群的住院病人，腎功能不全及年紀較高（大於六十歲）似乎是導致Allopurinol過敏症候群的重要因素。因此，在治療合併腎功能不全及年紀較高的痛風病患時，應調降allopurinol的劑量。有三個案例僅僅服用了100 mg的allopurinol就引起Allopurinol過敏症候群並伴隨E型免疫球蛋白的升高，這似乎暗示著第一型的過敏反應可能扮演部分的角色。其中一位病患因為對al1opurinol過敏病史的忽略導致前後共經歷了五次的Allopurinol過敏症候群。對這些病人有必要給予特別的提醒如佩戴記載有Allopurinol過敏症候群病史的手鐲，就能減少重覆過敏的發生。有十二位病患因為無症狀的高尿酸血症而接受allopurinol的治療，在南臺灣這是很普遍的醫療行為，但卻不是使用allop叮inol真正的適應症。若臨床醫師遵循使用al1opurinol的正確的適應症，就可以降低Allopurinol過敏症候群的發生。

Allopurinol is considered an effective and safe uric-acid lowering drug but occasional severe allopurinol hypersensitivity syndrome (AHS) may develop. Reviewing the records of 22 inpatients with AHS at our hospital, impaired renal function and old age seem to play an important role in the development of AHS. Three cases developed AHS with elevation of total IgE level only 5-lO minutes after taking 100mg of allopurinol. This finding seems to imply that type I hypersensitivity could play a part in the development of AHS. One patient experienced 5 episodes of AHS due to the ignorance of AHS history at other hospitals or drug stores, which could be avoided by giving these patients Medic-Alert bracelets, noting the history of AHS. Twelve cases (54.5%) received allopurinol because of asymptomatic hyper-uricemia, which is a common practice in Southern Taiwan but not an established indication for starting allopurinol. The chances of developing AHS could be lowered if the clinicians follow the proper indications for the use of allopurinol. We suggest that allopurinol should be prescribed in cases that exhibit proper indications. And the dosage for patients with impaired renal function and/or older age should be adjusted.