fear the low quantitative hCG

CONCERNED FOR ECTOPIC PREGNANCY?

--first trimester, vaginal bleeding, abdominal pain

--fear the low quant.

STUDY:

--by Kohn et al in 2003 from Acad EM
--looked at beta HCG levels in normal and abnormal early pregnancies

• 730 ED pt's (retrospective chart review)
• 253 abnormal IUP (mostly miscarriage)
• 381 normal IUP
• 96 Ectopics 

--Abnormal IUP and ectopic pregnancies had similar low beta HCG levels.

--Patients with HCG <1500 were twice as likely to have ectopic pregnancy (LR 2.24).

• 42% of the ectopics had HCG <1500
• only 7% of the normal IUP's had HCG <1500

BOTTOM LINE:

--Remember that the descriminatory beta HCG for TV US is >1500, making early pregnancy vs.ectopic with unclear ultrasound a tough decison without surgical pathology.

--HCG <1500 but non-diagnostic ultrasound, fear the ectopic

--stable patient: typical course of action is repeat HCG in 48 hrs

--unstable/borderline patient: have a low threshold of suspicion for ectopic

SCARY PARTING THOUGHT:

--case report of a ruptured ectopic with negative serum beta HCG

Submitted by S. Morris.

Reference(s): study, case report, picture