USMLE Step 1 Pearls

Question 1

Abdominal pain, ascites, hepatomegaly

Answer 1

Budd-Chiari syndrome
(post hepatic venous thrombosis)
- Associated with HCC (pg 370)
- Thrombosis or compression of hepatic veins with centrilobular congestion and necrosis –> congestive liver disease (hepatomegaly, varices, abdominal pain, eventual liver failure)
- Absence of JVD. Associated with hypercoagulable states, polycythemia vera, postpartum state, HCC. May cause nutmeg liver (mottled appearance)

Question 2

Abdominal pain, diarrhea, leukocytosis, recent antibiotic use

Answer 2

Clostridium difficile infection

• gram positive rod
• Examples include Fusobacterium, Clostridium, Bacteroides, and Actinomyces (FCBA - anaerobes Frankly Can’t Breathe Air)
• They lack catalase and/or superoxide dismutase and
  are thus susceptible to oxidative damage. Generally foul smelling (short-chain fatty acids), are diffciult to culture, and produce gas in tissue (CO2 and H2).
• Know clostridium tetani vs c. botulinum

Question 3

Achilles tendon xanthoma

Answer 3

Familial hypercholesterolemia ( LDL receptor signaling)