In Waterhouse-Friderichsen syndrome, bilateral adrenal hemorrhage leads to acute adrenal insufficiency. The most common causative organism is:
- A Streptococcus pneumoniae
- B Staphylococcus aureus
- C Neisseria meningitidis ✓
- D Pseudomonas aeruginosa
Correct answer: C. Neisseria meningitidis
Explanation
Waterhouse-Friderichsen syndrome is bilateral adrenal hemorrhagic infarction complicating overwhelming septicemia, classically caused by Neisseria meningitidis. The endotoxin-mediated DIC causes fibrin microthrombi in adrenal sinusoids with subsequent massive hemorrhage and cortical destruction, leading to acute adrenal crisis (shock, hyponatremia, hyperkalemia). Petechial/purpuric skin rash accompanies meningococcemia.
Reference: Robbins & Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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