In a third‑trimester pregnant woman presenting with leukocytosis, thrombocytopenia, mild hyperbilirubinemia, and pruritus, what further investigations and treatment are indicated?

Third Trimester Pruritus with Abnormal Labs: Immediate Workup and Management

Measure serum bile acids immediately—this patient likely has intrahepatic cholestasis of pregnancy (ICP), and you must determine the bile acid level to guide both treatment and delivery timing, as levels >100 μmol/L carry significant risk of stillbirth. 1

Critical First Step: Serum Bile Acid Testing

The combination of third-trimester pruritus with mildly elevated bilirubin (1.22 mg/dL) and transaminases (assuming "ot 240" refers to transaminases) strongly suggests ICP. Diagnosis requires serum bile acids >10 μmol/L in the setting of pruritus 1. The current labs show:

• WBC 14,100: Physiologic leukocytosis is normal in third trimester 2
• Platelets 132,000: Mild thrombocytopenia (5-10% of pregnancies) 3, 4
• Bilirubin 1.22 mg/dL: Consistent with ICP (typically <6 mg/dL) 1

Essential Differential Diagnosis Workup

Before confirming ICP, exclude these life-threatening conditions that require immediate delivery 1:

Rule Out Immediately:

• HELLP syndrome: Check LDH, peripheral smear for schistocytes, assess for hemolysis
• Pre-eclampsia: Blood pressure, proteinuria, symptoms (headache, visual changes, epigastric pain)
• Acute fatty liver of pregnancy (AFLP): Coagulation studies, glucose, ammonia
• Thrombotic thrombocytopenic purpura (TTP): If neurologic symptoms present, check ADAMTS13 activity 5

Additional Testing:

• Hepatitis C serology (HCV can present with elevated bile acids)
• Autoimmune markers: AMA, ANA, SMA for autoimmune hepatitis
• Liver ultrasound: Exclude extrahepatic biliary obstruction 6

Treatment Algorithm Based on Bile Acid Levels

If Bile Acids >10 μmol/L (Confirms ICP):

Start ursodeoxycholic acid (UDCA) 10-15 mg/kg/day in divided doses immediately 1. This reduces preterm birth and may prevent stillbirth 6.

Risk Stratification by Bile Acid Level:

Group 1: Bile acids <40 μmol/L

• Continue UDCA
• Weekly bile acid and LFT monitoring
• Consider delivery at 39 weeks 1

Group 2: Bile acids 40-100 μmol/L

• Continue UDCA
• Weekly bile acid monitoring (may rise with advancing gestation) 6
• Plan delivery at 36-39 weeks 1

Group 3: Bile acids >100 μmol/L ⚠️

• Deliver at 36 weeks or immediately if already past 36 weeks 1
• Stillbirth risk increases markedly after 35 weeks in this group 6

Additional Pruritus Management:

If UDCA insufficient, consider sequentially:

• Cholestyramine
• Rifampicin
• Guar gum or activated charcoal 6

Critical Monitoring Protocol

If initial bile acids are normal but pruritus persists:

• Repeat bile acids and LFTs every 2-3 weeks if <32 weeks gestation
• Weekly testing after 32 weeks (bile acids can rise with advancing gestation) 6

Common Pitfalls to Avoid

1. Don't dismiss mild thrombocytopenia: While gestational thrombocytopenia is common, combined with liver dysfunction it mandates ruling out HELLP/pre-eclampsia 3, 4

2. Don't delay bile acid testing: Pruritus alone warrants testing even if transaminases are only mildly elevated 1

3. Don't continue pregnancy to term with high bile acids: The stillbirth risk with bile acids >100 μmol/L after 35 weeks is unacceptable 1, 6

4. Don't stop UDCA abruptly: Discontinue at delivery, then taper over 2-4 weeks postpartum if symptoms persist 6

Postpartum Follow-Up

Verify that bile acids, transaminases, and bilirubin normalize within 3 months postpartum 1. If abnormalities persist beyond 6 weeks, investigate for underlying chronic liver disease 1. Consider genetic screening if there's family history of hepatobiliary disease or severe/early-onset presentation 6.