A 49-year-old man seeks a prescription for erectile dysfunction. He is 168 cm (5 feet 6 inches) tall and weighs 93 kg (body mass index 33). On physical examination, there are bilateral carotid bruits and a midline palpable abdominal pulsatile mass. Decreased hair is noted over the lower extremities, and a 1-cm shallow ulceration is present in the skin over the right first metatarsal head. He has decreased sensation to light touch and pinprick in the lower extremities. Laboratory findings include hemoglobin, 12.9 g/dL; hematocrit, 42%; WBC count, 8950/ mm3; and creatinine, 1.7 mg/dL. Which of the following laboratory findings is most likely to be present in this man?
Hemoglobin A1c elevation occurs in diabetes mellitus. The patient has complications of type 2 diabetes mellitus that are typical of obesity: a "diabetic foot" as a consequence of peripheral neuropathy and decreased sensation, advanced atherosclerosis with carotid arterial occlusion, and an atherosclerotic aortic aneurysm. Autonomic dysfunction with neuropathy can lead to erectile dysfunction. The oligo- clonal bands of IgG are characteristic for multiple sclerosis, which usually has more focal CNS involvement. Cushing disease owing to an ACTH-secreting pituitary adenoma leads to truncal obesity, skin that is easily bruised, and possibly to secondary diabetes mellitus, but not to advanced atherosclerosis. Hyperchromocysteinemia is a risk factor for atherosclerosis, but not for neuropathy. Anti-parietal cell antibodies occur in pernicious anemia with vitamin B12 deficiency, which can lead to decreased sensation in the lower extremities, but not to atherosclerotic complications.
Oligoclonal IgG bands in CSF
Hemoglobin A1c, 8.8%
Plasma ACTH, 119 pg/mL
Plasma homocysteine, 23 mmol/L
Misc.