Obstetrics Critical Illnesses

Q: All of the following favors the diagnosis of preeclampsia except?

A) Severe elevation of LDH
B) significant hypertension 
C) severe liver dysfunction 
D) severe elevation of AST 
E) illness after a gestation age of 20 weeks


Answer: A

In obstetric emergencies sometimes it is difficult to recognize the difference between look-alike clinical conditions. But few features are pathognomic to certain conditions.

Thrombotic thrombocytopenic purpura (TTP) is technically defined by a less than 10% activity of ADAMTS13 (but the test may take few weeks to be available). Similarly, hemolytic uremic syndrome (HUS) is dominant by a clinical feature of acute renal failure. 

One of the major differentiation between preeclampsia and TTP/HUS can be done on the basis of two relatively simple laboratory tests i.e. Lactate Dehydrogenase (LDH) and aminotransferase (AST). LDH is usually severely elevated in TTP/HUS while the severe elevation of AST is the feature of preeclampsia.

#obstetrics
#hepatology  



References: 

1.  Fyfe-Brown A, Clarke G, Nerenberg K, et al. Management of pregnancy-associated thrombotic thrombocytopenia purpura. AJP Rep 2013; 3:45. 

2. Allford SL, Hunt BJ, Rose P, et al. Guidelines on the diagnosis and management of the thrombotic microangiopathic haemolytic anaemias. Br J Haematol 2003; 120:556.