ABSTRACT
BACKGROUND: There are very few reports pertaining to Indian patients with neonatal diabetes mellitus (NDM). Activating or gain of function mutations of KATP channel genes namely KCNJ11 and ABCC8 are most predominant cause of permanent neonatal diabetes mellitus (PNDM). OBJECTIVES: To identify the genotype-phenotype correlation of KATP channel gene defects in a large series of (n = 181) Indian PNDM patients. METHODS: Direct sequencing of all exons of KCNJ11 and ABCC8 genes in all 181 patients with PNDM were performed. Clinical and biochemical data were collected. RESULTS: We have identified the molecular basis of KATP -NDM in 39 out of 181 patients (22%). Of these, 20 had KCNJ11 mutations and 19 had ABCC8 mutations, thus comprising 51% of KCNJ11 and 49% of ABCC8. There were four novel mutations (D1128Tfs*16, Y1287C, S1422T, and H1537R) in ABCC8 gene. Three patients with KCNJ11 mutations had developmental delay with DEND syndrome. In patients with ABCC8 mutations developmental delay was seen in seven out of 19 (36.8%). Of this, three patients (15.7%) had DEND phenotype and four (21%) had iDEND. Of the 39 patients, 33 (84%) patients were shifted to sulfonylurea therapy (glibenclamide). Of this, 19(57.5%) patients harbored KCNJ11 mutations and 14(42.1%) ABCC8 mutations. CONCLUSIONS: This is the first largest study in NDM patients in India demonstrating the importance of KATP channel gene mutation screening in PNDM and efficacy of glibenclamide for Indian patients with KATP -PNDM. The success rate of transfer is more in patients with KCNJ11 mutations compared with those with ABCC8 mutations.
Subject(s)
Diabetes Mellitus/genetics , KATP Channels/genetics , Female , Genetic Association Studies , Humans , India , Infant , Infant, Newborn , Male , MutationABSTRACT
Fluorodeoxy glucose positron emission tomography/computed tomography (FDG PET/CT) is increasingly being used for diagnosing various malignancies and surveillance of cancer recurrence, staging and screening in high-risk individuals. Due to its high sensitivity in picking up small dysplastic lesions, incidental lesions are detected frequently. We present two patients who underwent PET CT as part of cancer screening and were incidentally detected with adenomatous colonic polyps. Colonoscopy and biopsy confirmed the diagnosis.
ABSTRACT
CONTEXT: Neonatal diabetes is a rare disorder with an incidence of 1 in 215,000-500,000 live births with 50% of them having permanent neonatal diabetes mellitus. CASE REPORT: We present a case of permanent neonatal diabetes mellitus due to a C96Y (c.287G>A; p.Cys96Tyr) heterozygous mutation in the insulin (INS) gene. Both the patient and his father (who had childhood-onset insulin-requiring diabetes) were found to be carriers of a heterozygous missense mutation C96Y in exon 3 of the INS gene. It has been hypothesized that these mutations disrupt the folding of the proinsulin molecule and result in a misfolded protein or retention of the protein in the endoplasmic reticulum, resulting in endoplasmic reticulum stress and beta cell apoptosis. Subjects with this form of diabetes will need lifelong insulin therapy. CONCLUSION: Insulin gene mutations appear to be an important cause of neonatal diabetes worldwide. This is the first report of a case from the Indian subcontinent. It is important to carry out genetic tests for mutations linked to pancreatic beta cell dysfunction in all patients with persistent neonatal diabetes mellitus in order to decide on therapy.
