Review Question - QID 212577

A 25-year-old man presents to the emergency department for severe abdominal pain. The patient states that for the past week he has felt fatigued and had a fever. He states that he has had crampy lower abdominal pain and has experienced several bouts of diarrhea. The patient states that his pain is somewhat relieved by defecation. The patient returned from a camping trip 2 weeks ago in the Rocky Mountains. He is concerned that consuming undercooked meats on his trip may have caused this. He admits to consuming beef and chicken cooked over a fire pit. The patient is started on IV fluids and morphine. His temperature is 99.5°F (37.5°C), blood pressure is 130/77 mmHg, pulse is 90/min, respirations are 12/min, and oxygen saturation is 98% on room air. Laboratory studies are ordered and are seen below.

Hemoglobin: 10 g/dL
Hematocrit: 28%
Leukocyte count: 11,500 cells/mm^3 with normal differential
Platelet count: 445,000/mm^3

Serum:
Na+: 140 mEq/L
Cl-: 102 mEq/L
K+: 4.1 mEq/L
HCO3-: 24 mEq/L
BUN: 24 mg/dL
Glucose: 145 mg/dL
Creatinine: 1.4 mg/dL
Ca2+: 9.6 mg/dL
Erythrocyte sedimentation rate (ESR): 75 mm/hour

Physical exam is notable for a patient who appears to be uncomfortable. Gastrointestinal (GI) exam is notable for abdominal pain upon palpation. Ear, nose, and throad exam is notable for multiple painful shallow ulcers in the patient’s mouth. Inspection of the patient’s lower extremities reveals an erythematous, tender nodule. Cardiac and pulmonary exams are within normal limits. Which of the following best describes this patient’s underlying condition?