懷孕試驗陰性的葡萄胎

False Negative Pregnancy Test in Patients with Hydatidiform Mole

文獻報告，葡萄胎患者應全部為人類絨毛膜性釋放激素（β-hCG）陽性，對月經出現不正常的婦女，一般以小便懷孕試驗便可以快速臆測得到結果，藉此再尋找出與懷孕相關的病因。一旦小便懷孕試驗呈偽陰性時，便會延誤正確診斷的時機，增加病患的風險。偽陰性可能是因為血清中β-hCG濃度太高（＞1,000,000 mIU/mL），產生一種高劑量的鉤狀效應（hook effect）。解決的方法是將血清或尿液經稀釋後再測量，便可得到正確的數據。特別當患者懷疑有臨床上葡萄胎的疾病時，醫師須知道其檢驗數值有可能不可靠，知道該如何處理。

In review of molar pregnancies, 100% of patients had excessively elevated human chorionic gonadotropin(β-hCG) level. In women presenting with disturbance of their menstrual pattern, a sensitive urinary pregnancy test is a quick and easily performed test which should distinguish pregnancy-related causes. However, urine pregnancy test may show negative in a particular condition. A false negative pregnancy test may delay the diagnosis and proper care of the patients, and the likely cause for false negative results were reported to be the high-dose hook effect. In each of these reports, the serum β-hCG levels were determined to be greater than 1,000,000 mIU/mL. Dilution of the serum or urine sample in the appropriate setting can prevent delays and complications from a falsely low or negative pregnancy test. Clinicians should understand the possibility of inaccurate results and should know how to respond.