Shivaram Shastri

Idiopathic chronic pancreatitis in India: phenotypic characterisation and strong genetic susceptibility due to SPINK1 and CFTR gene mutations.

Objective To study the genetic predisposition, phenotype and prognosis of idiopathic chronic pancreatitis (CP). Design Prospective observational and case–control study. Setting Tertiary care academic centre. Patients Consecutive patients with CP. Interventions Detailed mutational analysis was done for the cationic trypsinogen, SPINK1 and CFTR genes with single-strand conformational polymorphism or restricted fragment length polymorphism, and sequencing. Clinical and disease characteristics of idiopathic versus alcoholic CP, and early onset versus late onset idiopathic CP were compared. Response to multimodality treatment (medical, endoscopic and/or surgical) and prognosis were analysed. Main outcome measures Genetic mutations, phenotypic characterisation and prognosis of idiopathic CP. Results Of the 411 patients with CP, 242 had idiopathic aetiology (age 27.50±11.85 years; 154 men). Malnutrition and cassava were not risk factors. SPINK1 N34S mutation was present in 42% of patients with idiopathic CP (vs 4% controls, p<0.001) and 17% of patients with alcoholic CP (p=0.016 compared with controls). In the CFTR gene, nine patients with idiopathic CP had mutations and 41 patients had polymorphisms (50% vs 10% controls, p<0.001). Diabetes developed in 35.53% of patients with idiopathic CP. About 85% of patients had significant pain relief with therapy. The probability of surviving for 35 years after onset of idiopathic CP was 83%. The typical features of tropical calcific pancreatitis were seen only in 5.8% of patients. Conclusion Strong genetic susceptibility due to SPINK1 and CFTR gene mutations, and comparative phenotype of idiopathic CP in India suggest that the term ‘tropical calcific pancreatitis’ is a misnomer.

Screening of families with autosomal recessive non-syndromic hearing impairment (ARNSHI) for mutations in GJB2 gene: Indian scenario

Several studies have reported that mutations in the GJB2 gene (coding for connexin26) are a common cause of recessive non‐syndromic hearing impairment. A GJB2 mutant allele, 35delG, has been found to have a high prevalence in most ethnic groups. Though mutations in the GJB2 gene have been shown to cause autosomal recessive deafness in Indian families, the frequencies of the various mutations are still unknown. In the present study, we analyzed 45 Indian families belonging to three different states, namely, Karnataka, Tamil Nadu, and Delhi with non‐syndromic hearing impairment and an apparently autosomal recessive mode of inheritance. All the families were initially screened for three mutations (W24X, W77X, and Q124X) by using allele‐specific PCR primers; mutations were confirmed by DNA sequencing. Families that were heterozygous or negative for tested mutations of the GJB2 gene were sequenced directly to identify the complementary mutation and other mutations in GJB2. Four families were homozygous for W24X, constituting around 8.8%. In two families, the affected individuals were compound heterozygotes for W24X; one family (DKB16) carried 35delG with W24X while the other family (DKB7) carried R143W with W24X. We suggest that W24X is a common allele among the mutations screened, causing autosomal recessive non‐syndromic hearing impairment (ARNSHI) in the Indian population.

Association of spink1 Gene Mutation and cftr Gene Polymorphisms in Patients With Pancreas Divisum Presenting With Idiopathic Pancreatitis

Background Pancreas divisum has been associated with idiopathic pancreatitis. However, the causal association remains controversial. Objective To study the gene mutations in patients with pancreas divisum presenting with idiopathic pancreatitis. Methods All consecutive patients with pancreas divisum presenting with recurrent pancreatitis were included in the study. Fifty healthy volunteers, 30 patients with chronic pancreatitis, and 14 patients with idiopathic recurrent acute pancreatitis without pancreas divisum served as controls. Patients and controls were tested for cationic trypsiongen gene, CFTR gene and SPINK1 gene mutations. Results Of the 12 patients with pancreas divisum and idiopathic pancreatitis, 4 had SPINK1 N34S gene mutation—3 were heterozygous and 1 was homozygous, and 1 had P55S mutation compared with 1 of 50 healthy controls with N34S mutation (P=0.001). The frequency of SPINK1 mutation was similar among patients with pancreas divisum and pancreatitis (41.6%), chronic pancreatitis (43.3%), and recurrent acute pancreatitis without pancreas divisum (35.7%). Five patients with pancreas divisum had polymorphisms in the CFTR gene. Conclusion Patients with pancreas divisum presenting with idiopathic pancreatitis had a higher frequency of SPINK1 gene mutation compared with healthy controls, which might be responsible as the sole-factor or a co-factor in causing pancreatitis in them.

Long-term daily high and low doses of azithromycin in children with cystic fibrosis: A randomized controlled trial

BACKGROUND Long-term administration of azithromycin (AZM) in children with cystic fibrosis (CF) has improved outcomes. However, the doses and schedule of administration are not very well studied in children with CF. METHODS A randomized controlled trial was conducted to compare the effect of two doses of azithromycin (5mg/kg/day and 15mg/kg/day) on FEV(1) and pulmonary exacerbations in children with cystic fibrosis. Enrolled children were randomly allocated to receive daily azithromycin (5mg/kg/day or 15mg/kg/day) for 6months. Clinical assessment and FEV(1) measurement were performed monthly. RESULTS 56 children (28 in high dose group and 28 in low dose group) were enrolled. 47 (24 and 23 children in low and high dose groups) completed 12months of follow up. There was no difference in clinical scores, FEV(1), pulmonary exacerbation rates between two groups at baseline, 6months and at 12months. Per protocol analysis revealed that pulmonary exacerbation increased after discontinuing AZM and there was significantly more increase after 12months of enrolment in children getting high dose azithromycin. There was no improvement in FEV(1) in either group at the end of treatment period. Children tolerated daily low as well as high dose AZM well for 6months. There was no significant side effect of azithromycin. CONCLUSION In this randomized controlled trial, we did not find differences in the effect of 2 doses (5mg/kg/day or 15mg/kg/day) of AZM on change in percentage predicted FEV(1), clinical scores, Pseudomonas colonization rates, pulmonary exacerbations and need for antibiotics. There was increase in exacerbations after stopping azithromycin in both the groups. Our results also suggest that the decrease in the incidence of LRTI persists only till 6months after discontinuing azithromycin.

Glutaric Acidemia Type 1-Clinico-Molecular Profile and Novel Mutations in GCDH Gene in Indian Patients

Glutaric acidemia I (GA I, #231670) is one of the treatable, autosomal recessively inherited metabolic disorders. Macrocephaly, acute encephalitis-like crises, dystonia and characteristic frontotemporal atrophy are the hallmarks of this disease. In this communication, we present the clinical, biochemical and molecular profile of seventeen GA I patients from 15 unrelated families from India and report seven novel mutations in GCDH gene (c.281G>A (p.Arg94Gln), c.401A>G (p.Asp134Gly), c.662T>C (p.Leu221Pro), c.881G>C (p.Arg294Pro), c.1173dupG (p.Asn392Glufs*5), c.1238A>G (p.Tyr413Cys) and c.1241A>C (p.Glu414Ala)). Out of these, c.662T>C (p.Leu221Pro) in exon 8 and c.281G>A (p.Arg94Gln) allele in exon 4 were low excretor alleles, whereas c.1241A>C (p.Glu414Ala), c.1173dupG and c.1207C>T (p.His403Tyr) in exon 11 were high excretor alleles. We conclude that c.1204C>T (p.Arg402Trp) is probably the most common mutant allele. Exons 11 and 8 are the hot spot regions of GCDH gene in Indian patients with GA I. An early diagnosis and timely intervention can improve the underlying prognosis. Molecular confirmation is helpful in providing genetic counselling and prenatal diagnosis in subsequent pregnancy.

Association of Angiotensin-Converting Enzyme Insertion(I)/Deletion (D) Genotype in Alzheimer's Disease Patients of North Indian Population

ABSTRACT Several lines of evidence support for the role of angiotensin-converting enzyme (ACE) in Alzheimers disease (AD) patients. Most human genetic studies have focussed on ACE insertion (I)/deletion (D) polymorphism and have yielded conflicting results. We have evaluated the association of ACE polymorphism with serum ACE activity in 95 AD patients and 110 healthy controls from north Indian population. In Alzheimers patients a higher frequency of D allele was detected (I/D ratio 0.53:0.47) compared with the control group (I/D ratio 0.54:0.45), the difference being not statistically significant (p > .05). AD patients were found to be more homozygous for the D allele (26.3%) compared with controls (20.8%). The observed genotype distribution was in agreement with Hardy- Weinberg equilibrium. We observed that the D/D genotype is more in patients with a higher serum ACE activity. The D allele and the D/D genotype in AD patients may influence increased risk of cognitive impairment.

Zinc Supplementation for One Year Among Children with Cystic Fibrosis Does Not Decrease Pulmonary Infection

BACKGROUND: Children with cystic fibrosis may have a deficiency of micronutrients, including zinc, which may affect their susceptibility to infections. There is a paucity of data on zinc supplementation among children with cystic fibrosis. We hypothesized that a pharmacologic dose of zinc administered daily for 12 months would reduce the need for antibiotics by 50%. METHODS: This double-blind randomized placebo-controlled trial was conducted among children with cystic fibrosis to assess the effect of zinc supplementation on the need for antibiotics and pulmonary function tests. The children, age 5–15 y, of either sex, received either 30-mg zinc tablets or similar looking placebo tablets daily in addition to standard care. They were followed up every month for a period of 12 months and whenever they had pulmonary exacerbations. Their serum zinc was estimated at baseline and at 12 months of enrollment. During each visit, the children underwent a pulmonary function test and sputum culture. RESULTS: Of a total of 43 children screened, 40 were enrolled, and of them, 37 completed the study. The median (interquartile range) number of days of the administration of antibiotics over 12 months of follow-up among the children receiving zinc was 42 (14–97) d. In the placebo group, it was 38 (15–70) d (P = .79). There were no significant differences in the percent-of-predicted FEV1 or change in FEV1 values at 12 months (P = .44). The number of children in whose respiratory specimens Pseudomonas was isolated was similar for the 2 groups at different time intervals. The adverse events reported were similar in the 2 groups. CONCLUSION: We did not find any significant difference in the need for antibiotics, pulmonary function tests, hospitalization, colonization with Pseudomonas, or the need for antibiotics for children with cystic fibrosis receiving zinc supplementation of 30 mg/d.

Influence of MDR1 and CYP3A5 genetic polymorphisms on trough levels and therapeutic response of imatinib in newly diagnosed patients with chronic myeloid leukemia

&NA; Polymorphisms in genes coding for imatinib transporters and metabolizing enzymes may affect imatinib pharmacokinetics and clinical response. Aim of this study was to assess the influence of polymorphisms in MDR1 and CYP3A5 genes on imatinib trough levels, cytogenetic and molecular response in patients with CML. Newly diagnosed patients with chronic‐phase CML started on imatinib therapy were enrolled and followed up prospectively for 24 months. The following single nucleotide polymorphisms were genotyped; C1236T, C3435T, G2677T/A in MDR1 gene and A6986G in CYP3A5 gene. Genotyping was done using PCR‐RFLP method and validated by direct gene sequencing. Trough levels of imatinib were measured using LC–MS/MS. Cytogenetic response was assessed by conventional bone‐marrow cytogenetics. Molecular response was assessed by qRTPCR using international scale. A total of 173 patients were included, out of which 71 patients were imatinib responders, while 102 were non‐responders. Marked inter‐individual variability in trough levels of imatinib was seen. Patients with GG genotype for CYP3A5‐A6986G (P = 0.016) and TT genotype for MDR1‐C3435T (P = 0.013) polymorphisms had significantly higher trough levels of imatinib. Patients with AA genotype for CYP3A5‐A6986G [RR = 1.448, 95% CI (1.126, 1.860), P = 0.029] and CC genotype for MDR1‐C1236T [RR = 1.397, 95% CI (1.066, 1.831), P = 0.06] & MDR1‐C3435T [RR = 1.508, 95% CI (1.186, 1.917), P = 0.018] polymorphisms were at high risk for failure of imatinib therapy. Patients with CGC haplotype for MDR1 polymorphisms had significantly lower imatinib trough levels and were at a higher risk of imatinib failure [RR = 1.547, 95% CI (1.324, 1.808), P < 0.001]. GG vs. non‐GG genotype for CYP3A5‐A6986G [adjusted OR: 0.246; 95% CI (0.116, 0.519); P < 0.001] and TT vs. non‐TT genotype for MDR1‐C1236T [adjusted OR: 0.270; 95% CI (0.110, 0.659); P = 0.004] & MDR1‐C3435T [adjusted OR: 0.289; 95% CI (0.135, 0.615); P = 0.001] polymorphisms were independent factors predicting imatinib response in multivariate analysis. To conclude, MDR1 and CYP3A5 genetic polymorphisms significantly influence plasma trough levels and therapeutic response of imatinib in patients with CML. Genotyping of these polymorphisms could be of value to individualize the therapy and optimize the clinical outcomes. Graphical abstract Figure. No caption available.

Prevalence of UGT1A6 polymorphisms in children with epilepsy on valproate monotherapy

BACKGROUND Valproate is a commonly used anticonvulsant drug. Uridine 5΄-diphospho (UDP)-glucuronosyltransferase (UGT) contributes to around 50% of valproate metabolism and its polymorphisms may be important for explaining the considerable variation in valproate levels in patients with epilepsy. AIM This study was aimed to analyze the genetic polymorphisms of UGT1A6 in Indian children with epilepsy and their potential influence on the pharmacokinetics of valproate. SETTING AND DESIGN This cross-sectional study was carried out in the Department of Pediatrics, All India Institutes of Medical Sciences (AIIMS), New Delhi, between March 2011 and July 2012. MATERIALS AND METHODS Children aged 3-12 years diagnosed with epilepsy on valproate monotherapy for at least 1 month were enrolled. They underwent a detailed clinical examination. The UGT1A6 polymorphisms were detected by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Random samples were checked by genetic sequencing. The steady-state plasma concentrations of valproate were measured by High Performance Liquid Chromatography (HPLC) and associated with UGT1A6 polymorphisms. RESULTS A total of 80 children were studied. The prevalence of UGT1A6 T19G was as follows: TT (45%), TG (38.8%), and GG (16.3%); that of UGT1A6 A541G was: AA (48.8%), AG (38.8%), and GG (12.5%); and that of UGT1A6 A552C was: AA (43.8%), AC (40%), and CC (16.3%). The association between valproate doses or standardized serum valproate concentration and the various UGT1A6 genotypes could not be studied reliably in this small study population. CONCLUSIONS The frequencies of UGT1A6 geneotypes and alleles were reported in the study population.

Do polymorphisms in MDR1 and CYP3A5 genes influence the risk of cytogenetic relapse in patients with chronic myeloid leukemia on imatinib therapy

Abstract Influence of polymorphisms in the genes coding for imatinib transporters and metabolizing enzymes on cytogenetic relapse in patients with chronic myeloid leukemia (CML) is not known. One hundred and four patients (52 cases with cytogenetic relapse and 52 controls without relapse) with chronic-phase CML on imatinib therapy and have completed 5 years of follow-up were enrolled. The following single nucleotide polymorphisms (SNPs) were genotyped; C1236T, C3435T, G2677T/A in MDR1 gene and A6986G in CYP3A5 gene, using PCR-RFLP method and validated by direct gene sequencing. Imatinib trough levels were measured using LC-MS/MS. Patients with CC genotype for MDR1-C1236T polymorphism were at significantly higher risk for cytogenetic relapse [OR =4.382, 95% CI (1.145, 16.774), p = .022], while those with TT genotype for MDR1-C3435T polymorphism had significantly lower risk of relapse [OR =0.309, 95% CI (0.134, 0.708), p = .005]. Imatinib trough levels were lower in patients with relapse compared to those without relapse (1551.4 ± 1324.1 vs. 2154.2 ± 1358.3 ng/mL; p = .041). MDR1-C3435T genotype [adjusted-OR: 0.266; 95% CI (0.111, 0.636); p = .003] and trough levels (p = .014) were independent predictors of relapse in multivariate analysis. To conclude, C1236T and C3435T polymorphisms in MDR1 gene and trough levels significantly influence the risk of cytogenetic relapse. MDR1-C3435T genotype might emerge as a potential biomarker to predict the risk of cytogenetic relapse in patients with CML.