Peripheral neuropathy is an early complication of type 2 diabetes in adolescence

Abstract

To screen for microvascular complications in adolescents with type 2 diabetes mellitus (T2DM). Seven adolescents with T2DM were assessed for early secondary complications. Median duration of diabetes was 1.8 (0.8-3.0) yr. All were assessed as follows: blood pressure, ophthalmologic examination for diabetic retinopathy, renal function, full blood count and vitamin B12 levels (to exclude B12 malabsorption - a side effect of metformin), random urine for microalbuminuria, an electrocardiogram (ECG) rhythm strip and podiatry performed by an experienced podiatrist. Testing for peripheral neuropathy included foot pulse palpation, tendo-Achilles reflexes, plantar callus test, large nerve fibre function (vibration and threshold for light touch/pressure) assessed by a 128-Hz tuning fork, and by the standard 10-g Semmes-Weinstein monofilament test, and small nerve fibre function (pain) assessed by pinprick neurotip. Four adolescents had evidence of peripheral neuropathy on clinical examination, with abnormal large and small nerve fibre function. Six had plantar callus present, and four had weak but palpable posterior tibial pulses. All had normal tendo-Achilles reflex and normal response to vibration. None had diabetic retinopathy or hypertension. Renal function, full blood count (FBC), B12 levels and ECGs were normal. None of 120 adolescents with type 1 diabetes mellitus (T1DM) assessed by the same podiatrist had any signs of peripheral neuropathy. Unlike T1DM, peripheral neuropathy can be present soon after diagnosis in those with T2DM. Children with T2DM need surveillance for complications from the time of diagnosis.