Childhood and Youth Onset Diabetes: A Single Centre Experience

Point Prevalence of Peripheral Neuropathy in Children and Adolescents with Type 1 Diabetes Mellitus

OBJECTIVE

To assess the point prevalence of peripheral neuropathy (PN) in children with type 1 diabetes mellitus (T1DM) and to determine their predictors.

METHODS

In this cross-sectional study, children aged 8-18 y with T1DM on insulin therapy for > 2 y and free from acute complications were enrolled. All participants were evaluated for symptoms of PN with diabetic neuropathy symptom (DNS) score and underwent a detailed neurological examination. Assessment of nerve dysfunction was done using nerve conduction studies (NCS). The disease-related factors that increase the risk of PN were determined.

RESULTS

Fifty children (52% boys) were enrolled with mean age of 12.2 ± 2.8 y and duration of diabetes 5.1 ± 2.1 y. No subject had clinical evidence or DNS score suggestive of PN. Twenty-eight (56%) children demonstrated subclinical neuropathy on NCS. Proportion of children with pure motor, pure sensory, and mixed motor-sensory neuropathy was 40%, 2%, and 14%, respectively. The peroneal nerve was the most common motor nerve affected. Poor glycemic control (HbA1c > 9%) and longer duration of diabetes (> 5 y) were significantly associated with the risk of PN (p value < 0.05).

CONCLUSION

A large proportion of children with T1DM have subclinical PN. Poor glycemic control and longer duration of diabetes are risk factors for nerve dysfunction. Neurophysiological studies should be performed in these children to facilitate early detection.

Heterogeneity in the aetiology of diabetes mellitus in young adults: A prospective study from north India

Background & objectives:

In contrast to Caucasians of European origin, the aetiology of diabetes mellitus (DM) in young adults in other ethnic groups, including Indians is likely to be heterogeneous and difficult to determine. This study was undertaken to determine the aetiology of diabetes in young Indian adults using a protocol-based set of simple clinical and investigation tools.

Methods:

In this prospective study, 105 Indian young adults with diabetes (age at onset 18-35 yr; duration <2 yr) were studied for a period of 1-3 years. Pancreatic imaging, fasting C-peptide, islet antibodies (against glutamic acid decarboxylase, tyrosine phosphatase and zinc transporter-8) and mitochondrial A3243G mutational analysis were performed in all patients. Four patients were screened for maturity-onset diabetes of the young (MODY) using next-generation sequencing.

Results:

Type 1 and type 2 diabetes mellitus (T1DM and T2DM) were equally frequent (40% each), followed by fibrocalculous pancreatic diabetes (FCPD, 15%). Less common aetiologies included MODY (2%), mitochondrial diabetes (1%) and Flatbush diabetes (2%). There was considerable phenotypic overlap between the main aetiological subtypes. Elevated islet antibodies were noted in 62 per cent of T1DM patients [positive predictive value (PPV) 84%; negative predictive value (NPV) 78%] while low plasma C-peptide (<250 pmol/l) was present in 56 per cent of T1DM patients [PPV 96% (after excluding FCPD), NPV 72%]. Using these tests and observing the clinical course over one year, a final diagnosis was made in 103 (99%) patients, while the diagnosis at recruitment changed in 23 per cent of patients.

Interpretation & conclusions:

The aetiology of diabetes in young adults was heterogeneous, with T1DM and T2DM being equally common. FCPD was also frequent, warranting its screening in Indian patients. Testing for islet antibodies and C-peptide in this age group had good PPV for diagnosis of T1DM.