Mao-Hung Lo

Urinary arginine methylation index associated with ambulatory blood pressure abnormalities in children with chronic kidney disease.

Arginine (ARG) metabolites are interrelated and are involved in chronic kidney disease (CKD) and cardiovascular disease. Twenty-four-hour ambulatory blood pressure monitoring (ABPM) appears to correlate with cardiovascular outcomes. We investigated the relationship between ARG metabolites, and their combined ratios in urine, and the ABPM profiles of children and adolescents with CKD. This cross-sectional study included 45 children and adolescents (age, 5-18 years) with stage 1 to 4 CKD. Each child underwent office blood pressure (BP) measurements, 24-hour ABPM, and urinary ARG metabolite determinations. Seventy percent of children with CKD had abnormal 24-hour ABPM profiles, including nocturnal hypertension, increased BP load, and nondipping nocturnal BP. The urinary ARG-to-asymmetric dimethylarginine (ADMA) ratio was lower, and the ADMA-to-symmetric dimethylarginine (SDMA) ratio was higher in children with advanced CKD (stages 2-4) than those with stage 1 CKD. CKD patients with BP abnormalities also had reduced urinary ARG and dimethylamine (DMA) levels. The higher urinary (ADMA+SDMA)-to-ARG ratios were correlated to ABPM abnormalities, including increased systolic BP load and non-dipping nocturnal BP. ABPM abnormalities were significantly associated with a high urinary (ADMA+SDMA)-to-ARG ratio, suggesting the possible involvement of methylated ARG in the development of hypertension among children with CKD.

Homocysteine and Arginine-to-Asymmetric Dimethylarginine Ratio Associated With Blood Pressure Abnormalities in Children With Early Chronic Kidney Disease

BACKGROUND Less attention has been paid to evaluating subclinical cardiovascular disease (CVD) in the early stage of pediatric chronic kidney disease (CKD). Ambulatory blood pressure monitoring (ABPM) and arterial stiffness are the earliest detectable assessments of subclinical CVD. Asymmetric dimethylarginine (ADMA) is an analog of L-arginine (ARG) that inhibits nitric oxide (NO) production; thus the ARG-to-ADMA ratio (AAR) is an index of NO. Homocysteine (HCY) is a risk factor for CVD and it can be metabolized to L-cysteine (CYS). Given that HCY and ADMA/NO are closely linked and related to hypertension, we therefore investigated whether ARG and HCY metabolites, arterial stiffness parameters, ABPM profile, and left ventricular hypertrophy (LVH) are interrelated in children and adolescents with early CKD. METHODSANDRESULTS This cross-sectional study included 57 pediatric patients with CKD stages 1-3. Two-thirds of the children with CKD stages 1-3 exhibited BP abnormalities accessed by ABPM. Children with CKD stages 2-3 had higher HCY, but lower CYS levels. The plasma HCY level was increased in children with LVH and abnormal ABPM. Systolic BP positively correlated with biomarkers AAR, HCY, and CYS. LV mass positively correlated with AAR, HCY, and CYS. CONCLUSIONS BP abnormalities were prevalent and associated with AAR, HCY, and CYS in children with early CKD. Our data highlighted the effect of NO and the HCY pathway on CKD-related hypertension.

Drug reaction with eosinophilia and systemic symptoms syndrome associated myocarditis: a survival experience after extracorporeal membrane oxygenation support

Myocarditis that develops because of the drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a life‐threatening disease. We report a case of DRESS‐associated myocarditis with cardiac failure that required extracorporeal membrane oxygenation (ECMO) for cardiovascular support.

Impact of Transcatheter Closure of Atrial Septal Defects in Pediatric Patients on Body Weight

BACKGROUND/PURPOSE Pediatric patients with atrial septal defect (ASD) may have failure to thrive. This study aimed to investigate body weight changes in pediatric patients after transcatheter closure of ASD. METHODS From June 2003 to September 2008, we enrolled 60 pediatric patients who underwent transcatheter closure of ASD. Changes in body weight percentile, heart rate, and resolution of right ventricular hypertrophy were compared before and after ASD closure. Patients were divided into two groups according to initial weight percentile: group A, <50(th) percentile (n = 39) and group B, ≥50(th) percentile (n = 21). Echocardiography and routine weight measurements were performed before the procedure and at 3, 6, and 12 months during follow-up. Clinical presentations, laboratory data, and outcomes were measured. RESULTS Increased body weight percentile (41±4 vs. 48±4, p<0.01), lower heart rate (100±2 beats/min vs. 89±2beats/min, p<0.01), and resolution of right ventricular hypertrophy (59/60 vs. 1/60, p<0.01) were achieved after ASD closure at the 12-month follow-up. Patients in group A were significantly younger (4.6±0.5 years vs. 7.0±0.9 years, p = 0.016), had a higher pulmonary/systemic blood flow ratio (2.2±0.1 vs. 1.8±0.l, p = 0.044), a largerratio of ASD diameter/body surface area (25.0±1.4 vs. 16.4±1.9, p<0.01), and higher percentage of weight gain increase ≥ 5 percentile compared with patients in group B (22/39 vs. 6/21, p = 0.039). CONCLUSION Transcatheter closure of ASD positively affects weight gain. An increase of 7 percentile weight was observed at 1 year of follow-up. Patients with a younger age, higher pulmonary/systemic blood flow ratio, and a larger ratio of ASD diameter/body surface area may have better weight gain after ASD closure.