Risk of tuberculosis comparison in new users of antitumour necrosis factor-α and with existing disease-modifying antirheumatic drug therapy.

WHAT IS KNOWN AND OBJECTIVE: Patients with rheumatic disease are at risk for infections. Evaluating antitumour necrosis factor (anti-TNF) drug-associated risk of infections requires justification of baseline risk in the population at high risk of infection. We examined the incidence of active tuberculosis (TB) and its risk factors in patients with rheumatic disease started with anti-TNF-α therapy or with existing disease-modifying antirheumatic drug (DMARD) therapy. METHODS: A retrospective cohort study of anti-TNF-α therapy new users (anti-TNF-α group) and those starting with a DMARD after the failure of at least one other DMARD or who had added to existing DMARD treatment (DMARD group) for rheumatic disease in the largest medical setting in Taiwan from 1 January 2005 through 31 November 2013 was conducted to determine relative risk of TB between patient groups. Patients in the DMARD group were stratified into "mild" and "severe" disease severity as proxies for low and high background risk of infection. RESULTS AND DISCUSSION: A total of 3640 patients were enrolled (anti-TNF: 955; DMARD: 2685). The incidence of TB was 903.9/100 000 patient-years for anti-TNF-α new users and 391.7/100 000 patient-years for DMARD switchers. In Cox regression model, adjusted HR for TB in the anti-TNF-α group was higher than for the entire DMARD group (aHR, 2.41; 95% confidence interval [CI], 1.2-4.85), subgroup with mild disease (2.91; 1.31-6.47) and subgroup with severe disease (1.65; 0.68-4.03). Significant independent risk factors for TB were being male, age ≥60 years, history of respiratory disease, glucocorticoids dose >7.5 mg/d and living in a TB-prevalent region. WHAT IS NEW AND CONCLUSION: Anti-TNF-α therapy was independently associated with increased risk of TB in patients with mild disease, but it was not significantly correlated in patients with severe disease after adjusting for confounders.

High salt exacerbates programmed hypertension in maternal fructose-fed male offspring.

BACKGROUND AND AIMS: Consumption of food and drinks containing high fructose (HF), which is associated with hypertension, is increasing steeply. Moreover, increased salt intake significantly increases hypertension risk. We examined whether maternal HF and postnatal high salt (HS) intake had synergistic effects on blood pressure (BP) elevation in adult offspring and determined the underlying mechanisms. METHODS AND RESULTS: Pregnant Sprague-Dawley rats received regular chow or chow supplemented with 60% fructose during the entire pregnancy and lactation periods. Half of the male offspring received 1% NaCl in drinking water from weaning to 3 months of age. Male offspring were assigned to 4 groups (control, HF, HS, and HF + HS) and were sacrificed at 12 weeks of age. Offspring in HF and HS groups developed hypertension, indicating that HF and HS synergistically increased BP. Postnatal HS intake increased Ace expression and decreased Agtr1b and Mas1 expression in the kidneys. Renal mRNA levels of Ace and Agtr1a were significantly higher in HF + HS group than in control group. Renal levels of Na-K-2Cl cotransporter, type 3 sodium hydrogen exchanger, and Na(+)/Cl(-) cotransporter were higher in HS and HF + HS groups than in control group. CONCLUSION: Postnatal HS intake exacerbated prenatal HF-induced programmed hypertension. HF and HS induced programmed hypertension by differentially inducing renin-angiotensin system and sodium transporters in the kidneys. Better understanding of the effect of the relationship between HF and HS on hypertension development will help prevent hypertension in mothers and children exposed to HF and HS.

Maternal citrulline supplementation prevents prenatal dexamethasone-induced programmed hypertension.

Glucocorticoids are administered to premature infants to accelerate pulmonary maturation. In experimental model, prenatal dexamethasone (DEX) results in reduced nephron number and adulthood hypertension. Asymmetric dimethylarginine (ADMA), an endogenous inhibitor of nitric oxide synthase (NOS), can cause oxidative stress and is involved in the development of hypertension. L-citrulline can be converted to l-arginine (the substrate for NOS) in the body. Thus we intended to determine if maternal L-citrulline therapy can prevent prenatal DEX-induced programmed hypertension by restoration ADMA/nitric oxide (NO) balance, alterations of renin-angiotensin system (RAS) and sodium transporters, and epigenetic regulation by histone deacetylases (HDACs). Male offspring were assigned to four groups: control, pregnancy rats received intraperitoneal DEX (0.2 mg/kg body weight) daily on gestational days 15 and 16 (DEX), pregnancy rats received 0.25% L-citrulline in drinking water during the entire pregnancy and lactation period (CIT), and DEX + CIT. We found DEX group developed hypertension at 16 weeks of age, which was prevented by maternal L-citrulline therapy. Prenatal DEX exposure increased plasma ADMA concentrations and reduced renal NO production. However, L-citrulline reduced plasma ADMA level and increased renal level of NO in DEX + CIT group. Next, prenatal DEX-induced programmed hypertension is related to increased mRNA expression of angiotensin and angiotensin II type 1 receptor, and class I HDACs in the kidney. Prenatal DEX exposure increased renal protein abundance of Na(+)/Cl(-) cotransporter (NCC), which was prevented by L-citrulline therapy. The beneficial effects of L-citrulline therapy include restoration of ADMA/NO balance and alteration of NCC, to prevent the prenatal DEX-induced programmed hypertension.

Determination of dimethylarginine dimethylaminohydrolase activity in the kidney.

Dimethylarginine dimethylaminohydrolase (DDAH) metabolizes asymmetric dimethylarginine to generate L-citrulline and is present in large quantities in the kidney. We present a new study that optimizes the Prescott-Jones colorimetric assay to measure DDAH-dependent L-citrulline generation in kidney homogenates. We found that the removal of urea with urease is necessary since urea also produces a positive reaction. Deproteinization with sulfosalicylic acid was found to be optimal and that protease inhibitors were not necessary. All assays were conducted in phosphate buffer, since other common additives can create false positive and false negative reactions. Arginase or nitric oxide synthase isoenzymes were not found to influence L-citrulline production. Our optimized L-citrulline production assay to measure DDAH activity correlated closely with the direct measure of the rate of asymmetric dimethylarginine consumption. Using this assay, we found that both superoxide and nitric oxide inhibit renal cortical DDAH activity in vitro.

Tumor lysis syndrome in an infant with Langerhans cell histiocytosis successfully treated using continuous arteriovenous hemofiltration.

Langerhans cell histiocytosis (LCH) is an enigmatic disease usually occurring in children. Tumor lysis syndrome (TLS) is a clinical syndrome associated with severe metabolic derangement and oliguric acute renal failure. In this report, we present the clinical course of an infant with advanced LCH who had TLS develop after chemotherapy. Treatment with continuous arteriovenous hemofiltration resulted in effective control of serum uric acid, potassium, creatinine, phosphorus, and blood urea nitrogen levels in the blood.

Microbiological spectrum of septicemia and peritonitis in nephrotic children.

From April 1993 to December 1997, 452 admissions of 231 children with nephrotic syndrome to Chang Gung Children's Hospital were retrospectively reviewed. There were 10 episodes of sepsis and 8 episodes of peritonitis in 18 children, and 14 microorganisms were cultured. Two children died due to Streptococcus pneumoniae sepsis. Gram-positive microorganisms (n=7) and Gram-negative microorganisms (n=7) were found in equal numbers. Enterococcus (1), Streptococcus pneumoniae (4), group D streptococcus (1), and Streptococcus viridans (1) were the Gram-positive microorganisms cultured. Two of 4 cases of Streptococcus pneumoniae sepsis were penicillin resistant. Gram-negative microorganisms included Enterobacter cloacae (1), Klebsiella pneumoniae (1), Escherichia coli (2), Acinetobacter baumannii (1), Neisseria meningitidis (1), and group B salmonella (1). The last three microorganisms have not been previously associated with nephrotic children. Vancomycin therapy to cover penicillin-resistant Streptococcus pneumoniae and a third-generation cephalosporin therapy to cover rare Gram-negative microorganisms should be considered in serious infections of nephrotic children.

Acrodermatitis enteropathica-like eruption during treatment of maple syrup urine disease: report of one case.

We describe a Chinese infant with maple syrup urine disease (MSUD) who had acrodermatitis enteropathica-like skin manifestations, edema, anemia, and diarrhea due to inadequate intake of branched-chain amino acids (BCAAs). A BCAA supplementation resulted in resolution of the eruption. This observation suggested the importance of monitoring plasma amino acids' levels for infants with metabolic disease on special formula.