Review Question - QID 214446

A 56-year-old man presents to the emergency department with complaints of cough. The patient reports productive cough and episodes of subjective fever shortly after returning from his cruise trip to Mexico 4 days ago. He endorses associated chills, headache, diarrhea, and general malaise. He denies hemoptysis, chest pain, or hematochezia. His past medical history is significant for diabetes and psoriasis for which he takes infliximab. A chest radiograph is shown in Figure A. Laboratory studies are shown below.

Serum:
Na+:128 mEq/L
Cl-: 101 mEq/L
K+: 3.7 mEq/L
HCO3-: 23 mEq/L
Urea nitrogen: 10 mg/dL
Glucose: 87 mg/dL
Creatinine: 0.8 mg/dL
Alkaline phosphatase: 34 U/L
Aspartate aminotransferase (AST, GOT): 8 U/L
Alanine aminotransferase (ALT, GPT): 10 U/L

What characteristic best describes the organism that caused this patient’s symptoms?