SERUM NEOPTERIN LEVEL IN PEDIATRIC PATIENTS WITH TYPE 1 DIABETES MELLITUS: RELATION TO DIABETIC NEUROPATHY

Abstract

Diabetes mellitus is a chronic metabolic disorder characterized by high plasma glucose caused by an impairment of insulin production, insulin action or both. Type 1 diabetes mellitus is potentially associated with serious microvascular and macrovascular complications. Diabetic peripheral neuropathy is the most common chronic complication of diabetes mellitus, with an incidence rate of about 50%. Early detection of sensory diabetic neuropathy remains a challenge in children because nerve conduction screening is painful, not commonly available and assesses only non-nociceptive large fibre function. Neopterin is a marker of inflammation and cellular immune response. High levels of neopterin were found in neurological diseases and type 2 diabetes. In view of these data, we measured the levels of neopterin in children and adolescents with type 1 diabetes and assessed its relation to glycemic control as well as its possible association with peripheral neuropathy and nerve conduction studies. This cross sectional study was carried out on 60 children and adolescents with type 1 diabetes mellitus (27 males and 33 females) attending the Pediatric Diabetes Clinic, Pediatric Hospital, Ain Shams University. Another group of 30 age- and sex-matched healthy individuals; 12 males and 18 females were enrolled as controls. The mean age of patients was 12.5 ± 3.1 years (range, 6-17 years) while that of controls was 11.8 ± 2.7 years (range, 6-15 years). All the included patients were subjected to: (i) detailed medical history with special emphasis on age at onset of diabetes, disease duration, insulin therapy and chronic diabetic complications (retinopathy, neuropathy, nephropathy, or cardiovascular ischemic events); (ii) thorough clinical examination laying stress on anthropometric measures, blood pressure, fundus examination and neurological assessment through performing neuropathy disability score; (iii) Nerve conduction studies were done for motor nerve conduction of posterior tibial nerve, common peroneal nerve, median nerve and ulnar nerve and sensory nerve conduction of median and ulnar nerves; (iv) Laboratory investigations including measurement of mean fasting and random blood glucose (FBG), routine liver and Kidney function tests, fasting lipid profile and mean HbA1c%. Determination of serum neopterin levels by enzyme linked immunosorbent assay (ELISA). In the current work, it was observed that the frequency of diabetic peripheral neuropathy in patients with type 1 diabetes according to neuropathy disability score was 40 (66.7%) patients out of 60, while nerve conduction studies detected that 30 (50%) patients out of 60 had this complication. The highest rate of motor abnormality was found in the right and left common peroneal nerves followed by the left tibial nerve while the highest rate of sensory abnormality was found in the left median nerve.