An 85-year-old man presented to Mayo Clinic in late summer 2003 with a 1-week history of increased shortness of breath on exertion. Two weeks prior to presentation, he had been on a canoeing trip in Montana. He had no known animal, insect, or tic exposure while there and had no significant rash. The patient had observed that his exercise tolerance had decreased prior to this presentation from walking 2 miles daily to only 3 to 4 blocks, mainly due to dyspnea. He had been hospitalized 6 months prior to presentation with community-acquired pneumonia. On that admission, he was diagnosed with chronic lymphocytic leukemia (CLL) B-cell type. He had not undergone pharmacologic treatment for CLL. His medications on presentation were doxazosin mesylate 4 mg daily, atenolol 50 mg daily, amlodipine 10 mg, and sertraline 50 mg daily. On presentation, he denied cough, weight loss, chest pain, or sputum production. He had chills and was found to have a fever of 38.9 °C. He was admitted to the medical service at St. Marys Hospital. His blood pressure was 144 mm Hg systolic and 76 mm Hg diastolic, his respiratory rate was 24 with 94% oxygen saturation on room air, and he appeared in mild respiratory distress with increased rate and work of breathing. He had bilateral crackles and reduced breath sounds on lung auscultation. He was alert and his cranial nerves were normal, as was his muscle strength. His muscle stretch reflexes were normal and symmetric. He had a wide-based, unsteady gait. He had no myoclonus, asterixis, or tremor. A chest x-ray showed bibasilar infiltrates or atelectasis. A CT angiogram of the chest showed lymphadenopathy and atelectasis or infiltrate in the right base, but was negative for pulmonary embolus. He was started on cefepime and doxycycline and later levofloxacin was added. His …