A 62-year-old male came to my office recently complaining of blurred vision for the last two weeks.
Earlier that day, he had been diagnosed with atrial fibrillation by his primary-care practitioner (PCP), and was prescribed a systemic beta blocker (carvedilol, Coreg) and was referred to a cardiologist.
His thyroid function studies had also been “slightly abnormal”—a longstanding issue. He complained about the blurry vision to his PCP, who told him it was likely due to hypothyroidism.
The patient’s previous medical history included having been treated for prostate cancer two years ago as well as a recent prostate specific antigen (PSA) value of zero
Upon questioning, he noted that he had been under great stress during the holidays and had been losing weight despite excess consumption of calories.
He also said that he had been drinking more water than usual. I asked him if his blood glucose had been measured earlier that day, and he was not sure.
With his most recent glasses (updated months earlier), the patient was 20/200 in each eye, which was easily corrected to 20/20 with a 3.00 D increase in myopic correction.
The patient is 73 inches tall and weighs 165 lbs, giving him a body mass index (BMI) of 21.77 kg/m2.
I checked his blood glucose in-office, which measured 515 mg/dl. A point-of-care glycosylated hemoglobin (A1C) was completed (measuring 14 percent, equivalent to an estimated mean glucose of 355 mg/dl over the last eight to 12 weeks). Clearly, this patient has diabetes.
Game over—right? Nothing more to do but refer the patient back to the PCP and get started on treatment, right?
I sent the patient to a local pharmacy to buy a home blood glucose meter and to text me a few more of his values that evening.
All were above 500 mg/dl. Given the patient’s low BMI, symptoms, and profound hyperglycemia, I was suspicious that he had latent autoimmune diabetes of adulthood (LADA), a type 1 diabetes that develops later in life, or—less likely but far more worrisome—pancreatic cancer given his prior medical history.
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