Efficacy and safety of D,L-3-hydroxybutyrate (D,L-3-HB) treatment in multiple acyl-CoA dehydrogenase deficiency.

PURPOSE: Multiple acyl-CoA dehydrogenase deficiency (MADD) is a life-threatening, ultrarare inborn error of metabolism. Case reports described successful D,L-3-hydroxybutyrate (D,L-3-HB) treatment in severely affected MADD patients, but systematic data on efficacy and safety is lacking. METHODS: A systematic literature review and an international, retrospective cohort study on clinical presentation, D,L-3-HB treatment method, and outcome in MADD(-like) patients. RESULTS: Our study summarizes 23 MADD(-like) patients, including 14 new cases. Median age at clinical onset was two months (interquartile range [IQR]: 8 months). Median age at starting D,L-3-HB was seven months (IQR: 4.5 years). D,L-3-HB doses ranged between 100 and 2600 mg/kg/day. Clinical improvement was reported in 16 patients (70%) for cardiomyopathy, leukodystrophy, liver symptoms, muscle symptoms, and/or respiratory failure. D,L-3-HB appeared not effective for neuropathy. Survival appeared longer upon D,L-3-HB compared with historical controls. Median time until first clinical improvement was one month, and ranged up to six months. Reported side effects included abdominal pain, constipation, dehydration, diarrhea, and vomiting/nausea. Median D,L-3-HB treatment duration was two years (IQR: 6 years). D,L-3-HB treatment was discontinued in 12 patients (52%). CONCLUSION: The strength of the current study is the international pooling of data demonstrating that D,L-3-HB treatment can be effective and safe in MADD(-like) patients.

Analysis of Biotinidase Activity in Serum by Digital Imaging Colorimetry Detection.

Biotinidase deficiency (BD) is an autosomal recessive inherited disorder of biotin recycling that leads to neurological and cutaneous consequences if left untreated. The clinical features of BD can be ameliorated or prevented by the administration of pharmacological doses of the vitamin biotin. Since it is a treatable disorder, BD is included in the newborn screening program in Türkiye as in many other countries. Therefore, monitoring of biotinidase enzyme activity (BEA) is of vital importance, especially for patients. The aim of this study was to develop a simple and reliable colorimetric method based on digital imaging for the analysis of BEA in serum samples. To determine the optimum distance and LED light source in the analyzer box that we fabricated in the laboratory, images of the solutions in a 96-well microplate were taken with a mobile phone camera, and each color space was examined. The most reliable relationship was between blank subtracted intensities of green channel and analyte concentrations, which was in the range of 35-400 ng/mL p-aminobenzoic acid (r2 = 0.999). The limit of detection and limit of quantification were 11 and 35 ng/mL, respectively. The proposed method was successfully applied to serum samples of 60 patients with BD and 60 healthy controls. We claim that the method can be easily performed for determination of BEA anywhere without needing expensive instruments.

Determination of NTBC in serum samples from patients with hereditary tyrosinemia type I by capillary electrophoresis.

Hereditary tyrosinemia type I is a serious metabolic disorder leading to liver failure. 2-(2-Nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC) is a relatively new drug which is used to prevent the accumulation of toxic metabolites in patients with hereditary tyrosinemia type I. In the present study, we have developed a new, simple, fast, and cost-effective capillary electrophoresis method for the quantitative monitoring of this drug in serum samples. Micellar electrochromatographic separation of NTBC was performed using 20 mmol/L phosphate and 40 mmol/L sodium dodecylsulfate (SDS) at pH 12 as running electrolyte. Separation of NTBC was achieved in around 4 min. Reproducibilities of migration times and corrected peak areas of NTBC (as R.S.D.%) were found as 0.73 and 1.99, respectively. The detection limit was 3.17 and the quantification limit was 10.6 micromol/L for NTBC using UV detection at 278 nm. The utility of the method was demonstrated by the detection of NTBC in serum samples from patients with hereditary tyrosinemia type I using this drug.

Tissue Doppler echocardiographic assessment of cardiac function in children with bronchial asthma.

BACKGROUND: The aim of the present study was to evaluate the role of tissue Doppler echocardiography in assessment of ventricular function in pediatric patients with bronchial asthma (BA). PATIENTS AND METHODS: Fifty-one pediatric patients with BA and 30 age- and sex-matched healthy subjects were studied. BA patients were divided into two groups: mild BA (n = 33) and moderate to severe BA (n = 18). All subjects were examined on conventional and tissue Doppler echocardiography, and 44 patients had pulmonary function tests on spirometry within 1 week of echocardiographic examination. RESULTS: Conventional echocardiographic parameters were all similar in mild asthmatic patients and control subjects. Tricuspid E velocity, E/A ratio and isovolumetric relaxation time (IVRT) in moderate and severe cases differed significantly from mild cases and control subjects. E', A', E'/A' ratio and IVRT of the lateral tricuspid annulus, and IVRT of the medial and lateral mitral annuli were different between mild cases and control subjects. E' velocity and IVRT of the lateral tricuspid annulus and IVRT of the medial and lateral mitral annuli were also different between mild cases and moderate to severe cases. Pulmonary function tests correlated well with E', E'/A' and IVRT of lateral tricuspid annulus. CONCLUSION: Patients with BA have subclinical right ventricular diastolic dysfunction even in the early stages. The severity of the functional impairment is parallel with the severity of the disease. Tissue Doppler echocardiography has a greater predictive value than conventional imaging, and is useful for evaluating ventricular function in patients with BA.