Identification and characterization of 20 novel pathogenic variants in 60 unrelated Indian patients with mucopolysaccharidoses type I and type II.

Mucopolysaccharidoses (MPS), a subgroup of lysosomal storage disorders, are caused due to deficiency of specific lysosomal enzyme involved in catabolism of glycosaminoglycans. To date more than 200 pathogenic variants in the alpha-l-iduronidase (IDUA) for MPS I and ∼500 pathogenic variants in the iduronate-2-sulphatase (IDS) for MPS II have been reported worldwide. The mutation spectrum of MPS type I and MPS type II disorders in Indian population is not characterized yet. In this study, we carried out clinical, biochemical, molecular and in silico analyses to establish the mutation spectrum of MPS I and MPS II in the Indian population. We conducted molecular analysis for 60 MPS-affected patients [MPS I (n = 30) (Hurler syndrome = 17, Hurler-Scheie syndrome = 13), and MPS II (n = 30) (severe = 18, attenuated = 12)] and identified a total of 44 [MPS I (n = 22) and MPS II (n = 22)] different pathogenic variants comprising missense, nonsense, frameshift, gross deletions and splice site variants. A total of 20 [MPS I (n = 14), and MPS II (n = 6)] novel pathogenic sequence variants were identified in our patient cohort. We found that 32% of pathogenic variants detected in IDUA were recurrent and 25% in MPS II. This is the first study revealing the mutation spectrum of MPS I and MPS II patients in the Indian population.

Global burden of genetic disease and the role of genetic screening.

It is estimated that 5.3% of newborns will suffer from a genetic disorder, when followed up until the age of 25 years. In developing, as compared to western countries, hemoglobinopathies and glucose-6-phosphate dehydrogenase deficiency have a higher incidence due to severe falciparum malaria in the distant past, and autosomal recessive disorders have a higher frequency due to greater proportion of consanguineous marriages. Chromosomal disorders have a combined frequency of 1 in 153 births, therefore screening for chromosomal disorders is essential, using biochemical markers, ultrasonography, and recently by non-invasive prenatal diagnosis based on cell-free fetal DNA in maternal plasma. Preconceptional counseling should be encouraged. For genetic disorders screening should be carried out, ideally after marriage, but before pregnancy. The disorders to be screened depend upon ethnicity. Metabolic disorders have a high incidence in developing countries due to greater rate of consanguineous marriages. Newborn screening is recommended to reduce the burden of these disorders, as many metabolic disorders can be treated. Hearing and critical congenital heart disease should both be screened in the newborn period.

Molecular analyses of novel ASAH1 mutations causing Farber lipogranulomatosis: analyses of exonic splicing enhancer inactivating mutation.

Farber lipogranulomatosis is a rare autosomal recessive lysosomal storage disorder caused by mutations in the ASAH1 gene. In the largest ever study, we identified and characterized ASAH1 mutations from 11 independent Farber disease (FD) families. A total of 13 different mutations were identified including 1 splice, 1 polypyrimidine tract (PPT) deletion and 11 missense mutations. Eleven mutations were exclusive to the Indian population. The IVS6+4A>G splice and IVS5-16delTTTTC PPT deletion mutations resulted in skipping of exon 6 precluding thereby the region responsible for cleavage of enzyme precursor. A missense mutation (p.V198A) resulted in skipping of exon 8 due to inactivation of an exonic splicing enhancer (ESE) element. This is the first report of mutations affecting PPT and ESE in the ASAH1 gene resulting in FD.

Trichohepatoenteric syndrome: founder mutation in asian indians.

Trichohepatoenteric syndrome (THES) is characterized by chronic diarrhea, dysmorphic facies and hair abnormalities. Hepatic involvement varies from no abnormality to cirrhosis and hemochromatosis. Recently, mutations in the tetratricopeptide repeat domain 37 (TTC37) gene were identified to cause THES. The c.2808G>A variation was suggested as a possible founder mutation among the South Asians. We further report 2 unrelated cases of Asian-Indian ethnicity (Gujrati) with THES, wherein targeted mutation analysis revealed the same mutation in homozygous form in both cases. These findings, as well as haplotype analysis, corroborate the founder mutation hypothesis amongst Asian Indo-Pakistani ethnic groups. A restriction enzyme-based method is also described to identify this founder mutation. One of our probands had multiple hepatic hemangiomas, a feature not previously observed in this syndrome.

Recombinant macrophage targeted enzyme replacement therapy for Gaucher disease in India.

OBJECTIVE: Gaucher disease in India has been reported only in a few case reports from India. The aim of the study was to assess the response to enzyme replacement therapy in Indian patients with Gaucher disease. DESIGN: Retrospective analysis of patients receiving CHO-derived recombinant macrophage-targetted glucocorebrosidase. SETTING: Five centers from India with experience in treating lysosomal storage disorders. PATIENTS: The diagnosis of Gaucher disease was confirmed by low glucocerebrosidase levels, though it was first made on splenectomy in 8 and on bone marrow examination in 9 patients. Twenty five of 52 patients diagnosed with Gaucher disease (17 Type I, 8 mild Type III) received treatment for >6 months. Indications for treatment included symptomatic anemia, thrombo-cytopenia, organomegaly, bone disease or mild neurological symptoms leading to impairment of quality of life. Patients with significant neurological involvement were excluded. The drug infusions were given intravenously every 15 days. MAIN OUTCOME MEASURES: Hemoglobin, platelet counts, liver and spleen volumes and growth parameters. RESULTS: 22 of the 25 children who survived were analyzed. After 6 months of treatment, the mean (range) increase in hemoglobin was 1.5 (-3.4 to 6.1) g/dL (P=0.01) and in platelet count was 32 x 10(9)/L (-98.5 x 109 to 145.5 x10(9))/L (P=0.02). The mean (range) increase in weight was 3 kg (-5.6 to 10.5) (P=0.04) and in height was 7.1 cm (0 to 26.5) (P=0.0003). Liver size decreased by a mean (range) of 38.5% (- 5.5 to 86.7) (P=0.0003) and the spleen size by 34.8% (0 to 91.7) (P=0.004). All patients had improvement in bone pains and in 2 patients, neurological symptoms improved with others remaining static. CONCLUSIONS: This is the first reported cohort of patients in India reporting our experience with imiglucerase enzyme replacement therapy for treatment of Gaucher Disease in India.

Rhizomelic chondrodysplasia punctata type 1: report of mutations in 3 children from India.

Rhizomelic chondrodysplasia punctata is a rare autosomal recessive disorder characterized by stippled epiphyses and rhizomelic shortening of the long bones. We report 3 subjects of rhizomelic chondrodysplasia punctata from India and the PEX7 mutations identified in them. The common PEX7-L292X allele, whose high frequency is due to a founder effect in the northern European Caucasian population, was not identified in these patients. Instead, 2 novel alleles are described, including 64_65delGC, which was present on a single PEX7 haplotype and could represent a common allele in the Indian population.

Patient comorbidity: relationship to outcomes of total knee arthroplasty.

One hundred six patients treated consecutively with total knee arthroplasty were evaluated to determine whether preoperative comorbidity (as measured by patient class, knee score, short form, anesthesia severity assessment, and number of medical comorbidities) correlated with perioperative and postoperative outcomes, including length of stay, total (and specific) hospital charges, and validated outcome scores. The length of stay for total knee arthroplasty was longer in patients who had lower preoperative knee scores and for patients with greater medical and musculoskeletal morbidity. Greater total hospital costs were associated with Class C patients and patients with poor anesthesia morbidity ratings. Patients who were debilitated medically and had four or more risk factors had decreased postoperative outcome scores. Preoperative medical and musculoskeletal morbidity influence the results of total knee arthroplasty. These findings may be useful to surgeons for optimizing resource utilization and outcomes in patients undergoing total knee arthroplasty. These data must be accounted for when contrasting total knee arthroplasty results between different surgeons and institutions.

ENTERIC FEVER - CULTURE AND SENSITIVITY PATTERN AND TREATMENT OUTCOME.

One hundred cases of enteric fever in the age group of 6 months to 12 years were analysed with respect to culture sensitivity pattern and treatment outcome. Patients were divided into 5 treatment groups - chloramphenicol, amoxycillin, trimethoprim-sulfamethoxazole + furazolidine, gentamicin + cephalexin and ciprofloxacin. Out of 91 culture positive cases, 100% were sensitive to ciprofloxacin followed by gentamicin (84.9%), cephalexin (83.6%), furazolidine (36.6%), trimethoprim-sulfamethoxazole (34.1%), chloramphenicol (34.0%) and amoxycillin (23.8%). In 60 cases resistant to chloramphenicol, resistance to other drugs varied from 20 to 88.3%. The treatment response was 100% to ciprofloxacin, 72.7% to chloramphenicol, 50% to gentamicin + cephalexin, 38.5% to trimethoprim-sulfamethoxazole + furazolidine and 12.5% to amoxycillin. Out of 48 cases who did not respond to initial regimen, 33 were treated successfully with ciprofloxacin and remaining with other drug regimens. Time taken for defervescence was shortest with gentamicin + cephalexin (4.6±2.0 days) followed by ciprofloxacin (6.1±2.5 days) and chloramphenicol (6.4±3.5 days). There were 3 deaths in this study.