MKSAP quiz: Screening after diagnosis
This month's quiz asks readers to choose screening tests for a 55-year-old man who was diagnosed with type 2 diabetes mellitus based on two HbA1c measurements of 7.8%.
A 55-year-old man is evaluated during a follow-up visit after he was diagnosed with type 2 diabetes mellitus based on two HbA1c measurements of 7.8%. His medical history is significant for dyslipidemia and hypertension. Medications are aspirin, atorvastatin, and lisinopril.
On physical examination, vital signs are normal. BMI is 33. The general physical examination, including nondilated eye examination, is normal.
The patient will initiate therapeutic lifestyle modifications, and metformin will be started.
In addition to spot urine albumin-creatinine ratio testing, which of the following screening tests should be done now?
A. Comprehensive foot examination and dilated eye examination
B. Fasting plasma glucose and 2-hour 75-g oral glucose tolerance test
C. Serum B12 and folate concentrations
D. 24-Hour urine protein and creatinine measurement
MKSAP Answer and Critique
The correct answer is A. Comprehensive foot examination and dilated eye examination. This item is available to MKSAP 18 subscribers as item 62 in the Endocrinology and Metabolism section. More information about MKSAP 18 is available online.
This patient requires a comprehensive foot examination and dilated eye examination. Patients with diabetes mellitus require monitoring for complications. A thorough foot examination should be done annually in patients with type 2 diabetes. Although this patient had an unremarkable visual foot inspection, he has not yet had a comprehensive foot examination, which is indicated at the time of diagnosis of type 2 diabetes and then annually thereafter. A comprehensive foot examination includes inspection of the skin, assessment of foot deformities, neurologic assessment (10-g monofilament testing with at least one other nerve assessment—pinprick, temperature, vibration, or ankle reflexes), and vascular assessment including pulses in the legs and feet. In patients with type 1 diabetes mellitus, a dilated comprehensive eye examination 5 years after diagnosis is appropriate; however, in patients with type 2 diabetes, a dilated comprehensive eye examination is indicated at time of diagnosis.
Prediabetes and diabetes can be diagnosed based on the elevated results from one of the following screening tests repeated on two separate occasions: fasting plasma glucose, 2-hour postprandial glucose during an oral glucose tolerance test, or hemoglobin A1c. This patient has two abnormal hemoglobin A1c measurements and additional testing with a fasting plasma glucose test and oral glucose tolerance test for the purposes of diagnosis is not warranted.
Although long-term use of metformin may be associated with vitamin B12 deficiency and periodic measurement of vitamin B12 levels should be considered in metformin treatment patients, B12 and folate measurements are not recommended at time of initiation of metformin therapy.
Annual screening for albuminuria in patients with type 2 diabetes should be undertaken starting at the time of diagnosis; this is done on a random spot urine sample as planned in this patient, not a 24-hour urine collection for protein and creatinine.
Key Point
- Screening for dyslipidemia, hypertension, a dilated eye examination, spot urine albumin-creatinine ratio, and a comprehensive foot examination should be performed at the time of diagnosis of type 2 diabetes.