Targeted exome sequencing in South Indian patients with Familial hypercholesterolemia.

BACKGROUND: Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder with elevated LDL-C levels which can ultimately lead to premature Coronary Artery Disease (CAD). OBJECTIVES: In presence of limited genetic data on FH in India, the present study was aimed to determine the mutation spectrum in Indian FH patients using a targeted exome sequencing. METHODS: 54 FH cases (31 index cases + 23 extended family members) were categorized according to Dutch Lipid Clinic Network Criteria (DLCNC). Targeted exome sequencing was performed using 23 gene panel associated with lipid metabolism. RESULTS: All subjects showed the presence of family history of CAD, 38(70%) patients had corneal arcus whereas only 06(11%) subjects had xanthomas. As per the DLCNC, definite, probable, possible and unlikely FH were 48%, 30%, 11% and 11% respectively. Mutations were observed in 12 of the 23 gene panel with CETP, APOA5, EPHX2 and SREBP2 genes were identified for the first time in Indian FH patients. All 19 mutations including a novel frame-shift mutation in LDLR gene were reported for the first time in Indian FH patients. These mutations were identified in 28(52%) subjects and interestingly ∼73% of the clinically identified FH patients didn't harbour mutations in FH classical genes (LDLR, ApoB, PCSK9). CONCLUSION: This is the first study in the South Indian FH patients to perform targeted exome sequencing. Absence of mutations in the FH classical genes strongly indicates the polygenic nature of FH, further underscoring the importance of targeted exome sequencing for identifying mutations in genetically diverse Indian population.

Shortcomings on genetic testing of Familial hypercholesterolemia (FH) in India: Can we collaborate to establish Indian FH registry?

Familial hypercholesterolemia (FH) is a common autosomal dominant disorder that affects ∼1 in 250-500 individuals globally. The only prevalence study in India shows FH in 15% of patients with premature CAD in North Indians. There are only 6 genetic studies in India of the total mutations, 32% are LDLR mutations, 4% are ApoB, 2% are PCSK9 mutations and the mutational spectrum for 37% is unknown. This calls for widespread genetic screening which could help identify definite FH patients. European Atherosclerosis Society-Familial Hypercholesterolemia Studies Collaboration (EAS- FHSC) has taken an initiative to develop a worldwide registry of FH. India is also a part of the collaboration and 3 groups from Mumbai, Delhi and Chennai are actively contributing to this registry. We believe this review might help to understand the Indian scenario of FH and investigators across India can contribute in managing FH in India and further help in the detection, diagnosis and treatment.

Screening of PCSK9 and LDLR genetic variants in Familial Hypercholesterolemia (FH) patients in India.

Familial Hypercholesterolemia (FH) is an autosomal, dominant, inherited disorder characterized by severely elevated LDL-cholesterol (LDL-C) levels with high risk for Coronary Artery Disease (CAD). There are limited genetic studies especially on genes other than Low Density Lipoprotein receptor (LDLR) conducted in Indian population. Thus, our aim was to screen the entire Proprotein Convertase Subtilisin/Kexin type 9 gene (PCSK9) gene & hotspot exons 3, 4 and 9 of LDLR gene in FH cases and controls. 50 FH cases were categorized into definite, probable and possible cases according to Dutch Lipid Network Criteria (DLNC) who were gender matched with 50 healthy controls. All 12 exons of PCSK9, and hotspot exons 3, 4 & 9 of LDLR gene were screened through High Resolution Melt (HRM) curve analysis. Enzyme linked immunosorbent assay was performed to measure circulating PCSK9 levels. Total cholesterol and LDL-C were significantly high in all three groups of cases. Total 8 nonpathogenic variants in exon 1, 5, 7 and 9 of the PCSK9 gene were detected. In LDLR gene, 3 known pathogenic and 1 benign variant were found in exon 3 & 4. In FH cases, PCSK9 levels were significantly high compared to controls (P = 0.0001), and were directly correlated to LDL-C (P = 0.0001) and Total Cholesterol (P = 0.0001). Our study is first to screen the entire PCSK9 gene in western part of India. Since no pathogenic variants were identified, it is possible that PCSK9 variants are clinically less relevant. However, 3 known pathogenic variants were found in the LDLR gene. These findings support our understanding of the genetic spectrum of FH in India.

Circulating miRNA-33: a potential biomarker in patients with coronary artery disease.

BACKGROUND: Circulating microRNAs (miRNA) are present in body fluids in stable, cell-free form. Likewise, these miRNAs can be identified in various stages of coronary artery disease (CAD) such as inflammation, endothelial dysfunction, proliferation and atherosclerosis among others. miRNA expression levels can be identified. AIMS AND OBJECTIVES: To determine the expression of circulating miRNAs (miR-126, miR-92, miR-33, miR-145 and miR-155) in CAD patients of Indian origin. MATERIAL AND METHODS: miRNA profiling analysis in blood plasma was performed by quantitative real-time-PCR (qRT-PCR) in 60 angiographically verified subjects including 30 CAD patients and 30 age- and gender-matched controls. Association between the expression of all five circulating miRNAs and clinical characteristics of patients with CAD were analysed using Medcalc statistics. The severity of CAD was assessed using SYNTAX score (SS). RESULTS: Expression of plasma miR-33 increased by 2.9 folds in CAD patients than in control group (p value ≥0.002) also it was found that miR-33 expression levels in mild cases (SS: ≤22) were significantly higher than CAD controls. There was a modest negative correlation between miR-33 and total cholesterol/high density lipoprotein ratio, triglycerides and very low density lipoprotein. CONCLUSION: The study reports a significant association between increased levels of plasma miR-33 and CAD. Thus, plasma miR-33 appears to be a promising non-invasive biomarker, but requires further validation in a large cohort.

Dose-response relationship of transcutaneous spinal direct current stimulation in healthy humans: A proof of concept study.

BACKGROUND: Non-invasive transcranial direct current stimulation has been shown to modulate cortical excitability in various studies. Similarly, recent preliminary studies suggest that transcutaneous spinal direct current stimulation (tsDCS) may engender a modulation effect on spinal and cortical neurons. OBJECTIVE: The purpose of this study was to evaluate the dose-response effects of tsDCS in healthy subjects and thereby lay groundwork for expanding treatment options for patients with spinal cord injury (SCI). METHODS: Nine healthy subjects received each of the following 2 tsDCS conditions: Anodal and cathodal, in random order with at least 1 week washout period between each session. In order to test safety and dose response, various current intensities were used (2, 2.5 and 3 mA) for 20 minutes. The active electrode was placed vertically over T10-T11, and the reference electrode was placed over the left shoulder. To evaluate corticospinal excitability, motor evoked potentials over soleus muscle elicited by transcranial magnetic stimulation were measured. To assess spinal cord excitability, H- and M- wave over soleus muscle to calculate Hmax/ Mmax ratio were measured. RESULTS: Linear regression showed a dose response with cathodal tsDCS on motor evoked potentials measured from the left leg as well as with anodal tsDCS on Hmax/ Mmax ratio measured from the left leg. CONCLUSIONS: These findings indicate tsDCS effects are dose-dependent. These effects should be investigated in a larger sample.

Familial Hypercholesterolemia (FH) Awareness Amongst Physicians in Mumbai, India.

BACKGROUND: Familial Hypercholesterolemia (FH) is a common genetic disorder affecting low density lipoprotein cholesterol (LDL-C) metabolism. Prolong exposure to elevated LDL-C results in the development of atherosclerotic lesions and a substantially increased risk of Coronary Artery Disease (CAD). In contrast, early detection and effective treatment of FH can result in a significant improvement in clinical outcomes. Despite these data, FH remains largely underdiagnosed and untreated. OBJECTIVE: To assess the awareness, knowledge, and clinical practices of FH by General Physicians (GPs) in Mumbai. METHODS: Physicians were requested to complete a survey comprising Multiple Choice questions (MCQs) on FH. The questionnaire inquired about; familiarity and awareness of the disorder, clinical description, prevalence, inheritance and their opinions on FH clinical services. RESULTS: Of the 79 GPs surveyed, 31% of them correctly described FH and only 28% knew about its prevalence. 51% perceived themselves to have an above moderate familiarity with this disorder. 46% of them were aware of the risk of cardiovascular disease (CVD) associated with FH. 80% of GPs were unsure or unaware of whether they had FH patients under their care. 50% and 33% of physicians identified statins as monotherapy and statin & ezetimibe as a combination therapy for FH respectively. CONCLUSION AND INTERPRETATION: Immediate attention should be focused on increasing awareness and knowledge about FH in India. Establishment of lipid clinic network will aid in improving care and clinical practices.

Time configuration of combined neuromodulation and motor training after stroke: A proof-of-concept study.

BACKGROUND: Intensive motor training is a therapeutic intervention that supports recovery of movement function after stroke by capitalizing on the brain's capacity for neuroplastic change. Peripheral nerve stimulation and transcranial direct current stimulation are neuromodulation techniques that can upregulate neuroplasticity and, in turn, enhance outcomes of motor training after stroke. Few studies have investigated possible adjuvant effects between peripheral nerve stimulation, transcranial direct current stimulation, and intensive motor training. OBJECTIVE: This proof-of-concept study investigated whether timing variations in neuromodulation paired with robot-assisted motor training effect differential outcomes for subjects with chronic, moderate-to-severe upper extremity impairment after stroke. METHODS: Ten subjects in the chronic phase (>12 months after stroke) of recovery completed the study. Subjects received 10 daily sessions of transcranial direct current stimulation either at the start (n = 4) or at the end (n = 6) of peripheral nerve stimulation preceding intensive motor training. Pre-post changes in motor function (Fugl-Meyer Assessment; Stroke Impact Scale) and neuroplasticity (transcranial magnetic stimulation) were assessed by condition. RESULTS: Significant improvement in Stroke Impact Scale (p = 0.02) and no change in Fugl-Meyer Assessment were associated with the start condition. No changes in Stroke Impact Scale and Fugl-Meyer Assessment were associated with the end condition. Only 1 subject in the start group had measurable neuroplastic responses and demonstrated an increase in ipsilesional cortical map volume. Only 1 subject in the end group had measurable neuroplastic responses and demonstrated a decrease in ipsilesional cortical map volume. Opposite shifts in ipsilesional cortical centers of gravity occurred relative to condition. CONCLUSION: In cases of moderate-to-severe impairment after stroke, transcranial direct current stimulation at the start, rather than the end, of peripheral nerve stimulation prior to motor training may effect better functional outcomes. Future research with a larger sample size is needed to validate the findings of this proof-of-concept study.

Troponin T and Heart Type Fatty Acid Binding Protein (h-Fabp) as Biomarkers in Patients Presenting with Chest Pain.

Acute coronary syndrome (ACS) is a term for a range of clinical signs and symptoms suggestive of myocardial ischemia. It results in functional and structural changes and ultimately releasing protein from injured cardiomyocytes. These cardiac markers play a major role in diagnosis and prognosis of ACS. This study aims to assess the efficacy of heart type fatty acid binding protein (h-FABP) as a marker for ACS along with the routinely used hs-TropT. In our observational study, plasma h-FABP (cut-off 6.32 ng/ml) and routinely done hs-Trop T (cutoff 0.1 and 0.014 ng/ml) were estimated by immunometric laboratory assays in 88 patients with acute chest pain. Based on the clinical and laboratory test findings the patients were grouped into ACS (n = 41) and non-ACS (n = 47). The diagnostic sensitivity, specificity, NPV, PPV and ROC curve at 95 % CI were determined. Sensitivity of hs-TropT (0.1 ng/ml), hs-TropT (0.014 ng/ml) and h-FABP were 53, 86 and 78 % respectively and specificity for the same were 98, 73 and 70 % respectively. Sensitivity, specificity and NPV calculated for a cut-off combination of hs-TropT 0.014 ng/ml and h-FABP was 100, 51 and 100 % respectively. These results were substantiated by ROC analysis. Measurement of plasma h-FABP and hs-TropT together on admission appears to be more precise predictor of ACS rather than either hs-Trop T or h-FABP.

Estimating the clinical impact of bringing a multimarker cardiac panel to the bedside in the ED.

OBJECTIVES: We examined the use of point-of-care (POC) testing of cardiac biomarkers against standard core laboratory testing to determine the time-savings and estimate a cost-benefit ratio at our institution. METHODS: We prospectively enrolled 151 patients presenting to the emergency department undergoing evaluation for acute coronary syndrome and conducted both central laboratory troponin T (TnT) testing at baseline and 6 hours as well as POC assays of creatine kinase MB, troponin I (TnI), and myoglobin at baseline and 2 hours. Sensitivity/specificity was calculated to measure the ability of the POC-accelerated pathway to identify enzyme elevations at rates parallel to our core laboratory. The time-savings were calculated as the difference between the median of the current protocol and the accelerated POC pathway. RESULTS: Troponin T tests were elevated in 12 patients, which were all detected by the accelerated pathway yielding a relative sensitivity of 100%. Time-saving between the accelerated pathway and core laboratory showed a saving of 390 minutes (6.5 hours). The accelerated POC pathway would have benefited 60% (95% confidence interval [CI], 52%-68%) of our patients with an estimated cost of $7.40 (95% CI, $6.40-$8.70) per direct patient care hour saved. CONCLUSION: Our data suggest that the use of an accelerated cardiac POC pathway could have dramatically impacted the care provided to a large percentage of our patients at a minimal cost per direct patient care hour saved.

Rapidly developing hyperglycemia during treatment with olanzapine.

OBJECTIVE: To report a case of rapidly occurring hyperglycemia that occurred in a geriatric patient 3 days after treatment with olanzapine. CASE SUMMARY: An 89-year-old man was admitted for dementia with behavioral disturbance and psychosis and was started on olanzapine 2.5 mg twice daily. Due to paranoia and agitation, the dose was increased to 5 mg twice daily after 2 days. Subsequently, he developed hyperglycemia (fasting blood glucose 138 mg/dL) that resolved when olanzapine was stopped and recurred (fasting blood glucose 150 mg/dL) after 2 days of rechallenge with olanzapine 2.5 mg twice daily. In addition, his overall medical status worsened, as he developed concurrent acute renal failure and became more confused and lethargic. The hyperglycemia once again resolved with discontinuation of the drug. DISCUSSION: We postulate that the rapid onset of hyperglycemia and the resulting medical sequelae were due to olanzapine. An objective causality assessment revealed that the adverse drug event was probable. There have been numerous case reports of hyperglycemia with olanzapine in the literature, but none reported hyperglycemia within days of initiation of the medication. Although weight gain often coincides with hyperglycemia in patients taking atypical antipsychotics, it does not seem to be a necessary causal factor. Recent data in animal studies have indicated that olanzapine and clozapine rapidly impair whole-body insulin sensitivity in a dose-dependent manner. CONCLUSIONS: Clinicians treating elderly patients with olanzapine should be aware of the potential for rapidly developing hyperglycemia and monitor such patients accordingly.

A retrospective review of enteroclysis in patients with obscure gastrointestinal bleeding and chronic abdominal pain of undetermined etiology.

Our purpose was to determine the diagnostic utility of enteroclysis in the evaluation of obscure gastrointestinal bleeding and abdominal pain of unknown etiology. This is a retrospective review of 97 consecutive patients (mean age, 54.1+/-17.5 [SD] years; 49 male and 48 female) who underwent enteroclysis at Temple University Hospital from January 1994 to October 2001 for the evaluation of obscure GI bleeding or chronic abdominal pain of undetermined etiology. Prior to enteroclysis all patients had an EGD and colonoscopy, which were nondiagnostic for their symptoms. Sixty-three patients (64.9%) had enteroscopy performed prior to enteroclysis that was also negative. Enteroclysis results were defined as positive based on anatomical or functional abnormalities. Analysis of the data included the percentage yield of positive exams, the percentage of positive results per symptom category, and the percentage of patients with a change in clinical management based on positive enteroclysis results. Ninety-seven patients underwent enteroclysis. The indications for enteroclysis were obscure GI bleeding in 67 patients (69.1%) and chronic abdominal pain in 30 patients (30.9%). The number of positive exams was 19 (19.6%). Fourteen of the 67 patients with the indication of GI bleeding had a positive exam (21%), while 5 of the 30 patients with chronic abdominal pain had a positive result (16.7%). There was a change in clinical management due to the enteroclysis results in 10 patients: 7 patients with GI bleeding (10%) and 3 patients with chronic abdominal pain (10%). Positive enteroclysis findings included adhesions (7), filling defects and masses (5), strictures (2), small bowel diverticulosis (1), mucosal abnormalities (3), and a motility disorder (1). The overall positive yield for enteroclysis was 19.6%, with a yield of 16.7% for chronic abdominal pain and 21% for gastrointestinal bleeding. Enteroclysis results changed the clinical management in approximately 10% of the patients.