Waterhouse-Friderichsen syndrome is characterized by bilateral adrenal hemorrhage and acute adrenal insufficiency. The most common causative organism is:

• A Staphylococcus aureus causing septic emboli
• B Pseudomonas aeruginosa in immunocompromised patients
• C Mycobacterium tuberculosis causing caseating granulomas
• D Neisseria meningitidis causing severe septicemia with DIC ✓

Explanation

Waterhouse-Friderichsen syndrome is most commonly caused by Neisseria meningitidis (meningococcemia) septicemia. Endotoxin-driven DIC leads to fibrin thrombi in adrenal sinusoids and bilateral hemorrhagic destruction of the adrenal cortex, causing acute Addisonian crisis. The petechial/purpuric rash, shock, and adrenal insufficiency constitute the classic triad. TB causes chronic adrenal insufficiency with caseating granulomas (Addison disease).

Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.