Inflammatory Bowel Disease USMLE Step 1 Practice Question
A 19-year-old man presents with periumbilical pain that later localizes to the right lower quadrant, accompanied by nausea and low-grade fever. Vital signs show temperature 38.2°C, heart rate 92/min, blood pressure 118/76 mmHg, and respiratory rate 16/min. Physical examination reveals tenderness at McBurney point without rebound rigidity. Laboratory studies show WBC 11,200/μL with left shift. Abdominal imaging demonstrates appendiceal wall thickening. Which of the following best explains the initial periumbilical location of this patient's pain?
Answer choices
- AVisceral afferent fibers from the midgut enter at T10Correct answer
- BInflammation of the pudendal nerve
- CCompression of the ilioinguinal nerve
- DSomatic innervation from the obturator nerve
- EIrritation of the phrenic nerve
- FReferred pain from sympathetic fibers originating at L1-L2 spinal segments
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