Automated enzymatic mitochondrial antibody assay for the diagnosis of primary biliary cirrhosis: applications of a routine diagnostic tool for the detection of antimitochondrial antibodies

BACKGROUND AND AIMS: An automated enzymatic mitochondrial antibody assay (EMA) kit for the diagnosis of primary biliary cirrhosis (PBC) has become commercially available recently. The aim of this study was to assess the clinical utility of the enzyme inhibition assay using this EMA kit for the diagnosis of PBC. METHODS: We tested the immunoreactivity of sera from 54 histologically confirmed Japanese PBC patients to the 2-oxo-acid dehydrogenase complex (2-OADC) enzymes by enzyme inhibition assay using commercially available TRACE (EMA) assay kit, and compared the results with those of indirect immunofluorescence, commercial enzyme-linked immunosorbent assay (ELISA) using MESACUP Mitochondria M2 kit, and immunoblotting on bovine heart mitochondria. RESULTS: Of the 54 sera, 43 (80%) were positive for antimitochondrial antibodies (AMA) by immunofluorescence, 39 (72%) for enzymatic inhibitory antibody to pyruvate dehydrogenase complex (PDC) by EMA, 33 (61%) for immunoglobulin G (IgG) class anti-PDC antibody by ELISA, and 53 (98%) for IgG, IgM, or IgA class antibodies against at least one of the 2-OADC enzymes by immunoblotting. Of these, 43 (80%) were positive for IgG, IgM, or IgA class antibodies against the E2 subunit of PDC (PDC-E2) by immunoblotting. Thirty-six of the 54 sera (67%) showed identical results in all of the four assays, and 40 (74%) were all negative or positive by EMA, ELISA, and immunoblotting in PDC-relevant reactivity. There was a significant correlation between the number of detected immunoglobulin classes of anti-PDC-E2 by immunoblotting and anti-PDC by EMA (P < 0.0001), and a significant inverse correlation between IgG class anti-PDC by ELISA and units of PDC activity by EMA (r = -0.87, P < 0.0001). CONCLUSIONS: Although EMA had lower sensitivity compared with immunofluorescence and immunoblotting, this assay should be included among the routine diagnostic tools for the detection of AMA specific to PBC in clinical laboratories because of its high specificity, objective read-out, and rapid turnaround time.     

Significance of Serum Vascular Endothelial Growth Factor Level in Patients with Idiopathic Pulmonary Fibrosis

Vascular endothelial growth factor (VEGF) is a key regulator of angiogenesis, which has been implicated in the pathogenesis of fibrotic lung diseases, including idiopathic pulmonary fibrosis (IPF). The aim of this study was to examine the clinical significance of the serum VEGF level for evaluating disease severity and progression. The levels of VEGF in serum were measured in 41 patients with IPF, 14 patients with lung cancer, and 43 healthy volunteers. We measured the serum levels of CRP, LDH, KL-6, SP-D, and the parameters obtained from arterial blood gas analysis and pulmonary function tests. High-resolution computed tomography (HRCT) was performed to determine the extent of the interstitial and the alveolar opacities. The ability of each biomarker to predict disease severity was estimated by measuring the area under the receiver operating characteristic curve (AUC). The VEGF levels of IPF patients with high alveolar–arterial difference of oxygen (AaDO₂) levels were significantly elevated than those with low AaDO₂ levels and those of healthy volunteers. When examined within the IPF group, a significant positive correlation was found between the VEGF levels and the HRCT interstitial score (p = 0.027) and the KL-6 levels (p = 0.037). Among several serum biomarkers, VEGF showed the largest AUC for predicting disease severity as defined by a high AaDO₂ value. There was an inverse correlation between the baseline VEGF level and the monthly change in percent predicted vital capacity. The serum VEGF level may reflect the severity of IPF and offer clinical benefits to predict the disease’s progression.     

Quantitative analysis of right ventricular function in patients with pulmonary hypertension using three-dimensional echocardiography and a two-dimensional summation method compared to magnetic resonance imaging

Magnetic resonance imaging (MRI) is considered the clinical reference standard for measuring the right ventricular (RV) volume and ejection fraction, although real-time 3-dimensional echocardiography (RT3DE) would be a preferred method owing to its convenience and availability for repetitive examinations. However, the feasibility, accuracy, and reproducibility of RT3DE have not been fully examined. The present study sought to validate the correlation of RT3DE with a 2-dimensional summation method compared to MRI for assessing the function of the right ventricle and to evaluate the RV function in patients with pulmonary hypertension (PH). Thirty patients with PH underwent both RT3DE and MRI. The right ventricle was reconstructed with RT3DE using a 2-dimensional summation method to analyze the MRI measurements. The RV end-diastolic volume, RV end-systolic volume, and RV ejection fraction were measured. Fifteen normal subjects underwent the same echocardiographic protocol for comparison. The RV end-diastolic volume index, RV end-systolic volume index, and RV ejection fraction measured using RT3DE correlated well with those measured using MRI (R = 0.96, p <0.001; R = 0.96, p <0.001; p = 0.93, and p <0.001, respectively). All inter- and intraobserver variability values for the RV end-diastolic volume, RV end-systolic volume, and RV ejection fraction were <17%. Both the RV end-diastolic volume index and the RV end-systolic volume index were significantly enlarged in those with PH compared to those in the normal subjects (RVEDVI 123 ± 42 ml/m2 vs 74 ± 12 ml/m2; RVESVI 86 ± 33 ml/m2 vs 26 ± 5 ml/m2 in those with PH and the normal subjects, respectively, p <0.0001). In contrast, the RV ejection fraction was significantly reduced in the patients with PH compared to that in the normal subjects (30 ± 12% vs 65 ± 6%, respectively, p <0.01). Thus, RT3DE with a 2-dimensional summation method might provide comparable and feasible measurements of the RV volume in patients with PH compared to MRI.     

Peripheral T-cell lymphoma, not otherwise specified: a report of 340 cases from the International Peripheral T-cell Lymphoma Project

The International Peripheral T-cell Lymphoma Project is a collaborative effort to better understand peripheral T-cell lymphoma (PTCL). A total of 22 institutions submitted clinical and pathologic material on 1314 cases. One objective was to analyze the clinical and pathologic features of 340 cases of PTCL, not otherwise specified. The median age of the patients was 60 years, and the majority (69%) presented with advanced stage disease. Most patients (87%) presented with nodal disease, but extranodal disease was present in 62%. The 5-year overall survival was 32%, and the 5-year failure-free survival was only 20%. The majority of patients (80%) were treated with combination chemotherapy that included an anthracycline, but there was no survival advantage. The International Prognostic Index (IPI) was predictive of both overall survival and failure-free survival (P < .001). Multivariate analysis of clinical and pathologic prognostic factors, respectively, when controlling for the IPI, identified bulky disease (≥ 10 cm), thrombocytopenia (< 150 × 10(9)/L), and a high number of transformed tumor cells (> 70%) as adverse predictors of survival, but only the latter was significant in final analysis. Thus, the IPI and a single pathologic feature could be used to stratify patients with PTCL-not otherwise specified for novel and risk-adapted therapies.     

Cardio-ankle vascular index could reflect plaque burden in the coronary artery

Cardio-ankle vascular index (CAVI) using the volume plethysmographic method is a noninvasive atherosclerotic indicator which is not influenced by blood pressure. Coronary intravascular ultrasound (IVUS) is a reliable technique to measure progression of atherosclerosis. The association between CAVI and IVUS has not been reported. The aim of this study was to evaluate the association between CAVI and the plaque burden measured by IVUS in the left main coronary artery (LMCA) in patients with coronary heart disease and normal LMCA. Cardio-ankle vascular index was significantly correlated with percentage plaque area (r = .649, P < .0001) measured by IVUS in the most diseased segment of LMCA. Cardio-ankle vascular index remained significant among cardiovascular disease risk factors included in the multiple regression analysis predicting percentage plaque area. Cardio-ankle vascular index was a good atherosclerotic indicator and associated with the plaque burden in nonculprit and angiographically normal LMCA.     

Double duct-to-mucosa pancreaticojejunostomy for bifid pancreatic duct

We report a pancreaticojejunostomy with double duct-to-mucosa anastomotic technique after pyloruspreserving pancreaticoduodenectomy for chronic pancreatitis with bifid pancreatic duct. A 49-year-old Japanese man was diagnosed preoperatively as having chronic pancreatitis with common bile duct stricture and pseudocyst of the pancreatic head. In a pancreaticoduodenectomy, the main pancreatic duct (7mm in diameter) and a secondary pancreatic duct (4mm in diameter) were identified intraoperatively at the transected surface. Pancreatography showed the main pancreatic duct as well as thesecondary pancreatic duct that drained the remaining dorsal pancreas, allowing us to diagnose bifid pancreatic duct. The pancreaticojejunostomy was performed in an end-to-side manner to create double duct-to-mucosa anastomoses and to approximate the pancreatic parenchyma and jejunal seromuscular layers. Although bifid pancreatic duct is a rare anatomical anomaly, it behooves every surgeon who performs pancreatic resections to be aware of this entity and the techniques for dealing with it.     

Association of plasma atrial natriuretic peptide, N-terminal proatrial natriuretic peptide, and brain natriuretic peptide levels with coronary artery stenosis in patients with normal left ventricular systolic function

PURPOSE: To examine whether coronary artery stenosis affects plasma levels of atrial natriuretic peptide (ANP), N-terminal proatrial natriuretic peptide (proANP), and brain natriuretic peptide (BNP) in patients with normal left ventricular systolic function. METHODS: We studied 104 consecutive patients with normal left ventricular function and suspected coronary artery stenosis. Plasma natriuretic peptide levels were measured by immunoradiometric assays. RESULTS: Plasma levels of ANP, N-terminal proANP, and BNP were higher in patients with (n = 65) than in those without (n = 39) coronary artery stenosis, whereas hemodynamic variables were similar. Patients who had coronary artery stenosis with only distal lesions (n = 36) had higher levels of all three natriuretic peptides than did patients with no coronary artery stenosis. N-terminal proANP levels were significantly higher in patients who had coronary artery stenosis with proximal lesions (n = 29) than in patients who had coronary artery stenosis with only distal lesions and those with no coronary artery stenosis. Multiple logistic regression analysis revealed that N-terminal proANP, but not ANP or BNP, was independently associated with coronary artery stenosis after adjusting for clinical and demographic variables (odds ratio per 100 fmol/mL increase = 1.9; 95% confidence interval: 1.9 to 2.6; P = 0.01). However, the sensitivity, specificity, and positive and negative predictive values of each peptide were not sufficiently high to be used for prediction. CONCLUSION: N-terminal proANP may be associated with clinically important coronary artery stenosis in patients with normal left ventricular systolic function, but its clinical usefulness may be limited.     

A novel missense mutation in the SCN5A gene associated with Brugada syndrome bidirectionally affecting blocking actions of antiarrhythmic drugs

Brugada syndrome is an inherited cardiac disorder caused by mutations in the SCN5A gene encoding the cardiac sodium channel alpha subunit, which can lead ventricular fibrillation and sudden death. Inattentive use of antiarrhythmic drugs potentially triggers fatal cardiac arrhythmias through further reduction of sodium current (I(Na)). We studied the molecular mechanism underlying a case of Brugada syndrome that showed no response to a class Ic antiarrhythmic drug. Molecular genetic studies of a patient with Brugada syndrome identified a novel mutation in SCN5A, which causes substitution of serine for asparagine (N406S) in S6 of domain I (IS6). The provocation test with pilsicainide, a class Ic antiarrhythmic drug, failed to exacerbate ST-segment elevation in this case. Electrophysiological analyses of the N406S-mutant channel expressed together with the beta1 subunit in HEK293 cells showed that the voltage dependence of activation was positively shifted by 16 mV and that intermediate inactivation was enhanced. Whereas tonic block by pilsicainide was not changed in the N406S channel, use-dependent block by pilsicainide was almost completely abolished, consistent with the clinical findings of the negative provocation test. In contrast, the N406S channel showed stronger use-dependent block by quinidine than the wild-type channel. We demonstrate a novel Brugada mutation N406S, which is associated with the discordant effects on blocking actions of antiarrhythmic drugs as well as the multiple channel gating defects. We emphasis that an antiarrhythmic drug may exert unpredicted effects in patients with channel mutations.     

Long‐term outcome of stereotactic body radiotherapy for patients with small hepatocellular carcinoma

Aim

To evaluate the long‐term outcome of stereotactic body radiotherapy in patients with small hepatocellular carcinoma who were ineligible for resection or ablation therapies.

Methods

A total of 65 patients with 74 hepatocellular carcinomas (median tumor size 16 mm) were enrolled in the present study. They were treated with the prescribed dose of 48 Gy in four fractions at the isocenter. We extended the observation period and analyzed long‐term outcomes, including overall survival, progression‐free survival, local control, and various prognostic factors, in these patients.

Results

The median follow‐up period was 41 months for all patients and 62 months for surviving patients. The 3‐ and 5‐year overall survival rates were 56.3% (95% confidence interval, 44.1–68.5%) and 41.4% (95% confidence interval, 28.7–54.1%), respectively. The 3‐ and 5‐year progression‐free survival rates were 25.4% (95% confidence interval, 14.0–36.8%) and 10.6% (95% confidence interval, 1.5–19.8%), respectively. The 3‐ and 5‐year local control rates were both 100% (95% confidence interval 100%). Liver toxicities exceeding grade 3 were observed in 15 patients (23.1%). The proportion of patients who had grade ≥3 toxicities did not increase. Adverse effects (grade ≤2) presented as significant prognostic factors of overall survival, while TNM stage (T1N0M0) was a significant prognostic factor of progression‐free survival after multivariate analysis.

Conclusions

Stereotactic body radiotherapy was effective for patients with small hepatocellular carcinomas who were ineligible for resection or ablation therapies. The incidence of grade ≥3 adverse effects did not increase, even after longer follow‐up times.     

Identification of subtype-specific genomic alterations in aggressive adult T-cell leukemia/lymphoma

Aggressive adult T-cell leukemia/lymphoma (ATLL) such as acute and lymphoma types are fatal diseases with poor prognosis. Although these 2 subtypes feature different clinicopathologic characteristics, no detailed comparative analyses of genomic/genetic alterations have been reported. We performed array-based comparative genomic hybridization for 17 acute and 49 lymphoma cases as well as real-time quantitative polymerase chain reaction (PCR) to identify the target genes of recurrently amplified regions. Comparison of the genome profiles of acute and lymphoma types revealed that the lymphoma type had significantly more frequent gains at 1q, 2p, 4q, 7p, and 7q, and losses of 10p, 13q, 16q, and 18p, whereas the acute type showed a gain of 3/3p. Of the recurrent high-level amplifications found at 1p36, 6p25, 7p22, 7q, and 14q32 in the lymphoma type, we were able to demonstrate that CARMA1 is a possible target gene of the 7p22 amplification for the lymphoma type but not for the acute type. Furthermore, we found BCL11B overexpression in the acute type regardless of the 14q32 gain/amplification, but no or low expression of the gene in the lymphoma type. These results suggest that acute and lymphoma types are genomically distinct subtypes, and thus may develop tumors via distinct genetic pathways.