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Renal proximal tubulopathy in Fanconi‐Bickel syndrome is caused by impaired basolateral glucose transport via GLUT2 and consequently, intracellular accumulation of glucose and glycogen. SGLT2 inhibitors act on apical glucose reabsorption of renal proximal tubular cells. The purpose of this study was to retrospectively describe the first experiences with repurposing the SGLT2 inhibitor empagliflozin to treat the generalized tubulopathy in Fanconi‐Bickel syndrome. A case series was conducted of seven persons from five families (five males, two females; three children, who were 14y5m, 2y9m, and 1y6m old) with genetically confirmed Fanconi‐Bickel syndrome, off‐label treated with empagliflozin. Median (range) age at start of empagliflozin was 27 years (1y6m – 61y) and duration of follow‐up under empagliflozin treatment was 169 days (57–344). Under empagliflozin (up to 25 mg/d), biochemical parameters of tubular cell integrity (urinary N‐acetyl‐glucosaminidase) and/or tubular functions (including urinary α1‐microglobulin) improved in all persons with Fanconi‐Bickel syndrome, albeit to varying degrees. Clinically, supplementations (i.e., phosphate, alkali, carnitine, and alfacalcidol) could be completely discontinued in the three children, whereas results in the four adult patients were more variable and not as significant. Empagliflozin was well‐tolerated and no symptomatic hypoglycemia was observed. In conclusion, SGLT2 inhibitors such as empagliflozin shift the metabolic block in Fanconi‐Bickel syndrome, that is, they intervene specifically in the underlying pathophysiology and can thus attenuate renal proximal tubulopathy, especially when started in early childhood. [ABSTRACT FROM AUTHOR]

Uvod. Presejanje novorojencev v Sloveniji se je začelo leta 1979 s presejanjem za fenilketonurijo (PKU). Leta 1981 je bil v program presejanja dodan še kongenitalni hipotireoidizem (CH). Cilj te raziskave je analiza podatkov presejanja novorojencev v Sloveniji v obdobju med letoma 1993 in 2012 za PKU ter med letoma 1991 in 2012 za CH. Metode. Vzorci krvi so bili odvzeti petim novorojencem med tretjim in petim dnem življenja. Pri presejanju za PKU se uporablja fluorometrična metoda, presejanje za CH pa poteka z metodo DELFIA. Rezultati. Od leta 1993 do leta 2012 je bil presejalni test za PKU izveden pri 358.831 novorojencih. Pri 57 otrocih je bil PKU potrjen. Pri 427.396 novorojencih med letoma 1991 in 2012 je bil izveden presejalni test za CH. Pri 184 otrocih je bil CH potrjen. V navedenih obdobjih je bila incidenca PKU 1:6769 in incidenca CH 1:2323. Zaključki. Uspešna implementacija presejanja novorojencev za PKU in CH je imela pomembno vlogo pri preprečevanju resnih zapletov pri obolelih otrocih. Smiselno bi bilo v program presejanja vključiti nove metabolne bolezni.

Background: Inborn errors of metabolism (IEM) are disorders with a block in the metabolic pathway caused by a genetic defect of a specific enzyme. Although each of these diseases is quite rare, as a group they account for a significant proportion of newborn and childhood morbidity and mortality. Early diagnosis is important to prevent complications or even death of the child. Selective screening is an important diagnostic tool for the diagnosis of IEM. Methods: In Slovenia, symptomatic patients with suspected IEM are referred to the University Children's Hospital Ljubljana. Techniques used for selective screening are gas chromatography-mass spectrometry, ion exchange chromatography-post-column derivatization, liquid chromatography-tandem mass spectrometry and isoelectric focusing. Fluorimetric method is used for enzyme activity measurement. Results: There are 168 patients with amino and organic acidemias, 5 patients with disorders in fatty acids metabolism, 1 patient with a congenital disorder of glycosylation, 42 patients with Fabry disease (of which 37 are adult) and 20 patients with Gaucher disease (of which 18 are adult) in the Slovenian Register for Rare Diseases. Conclusions: In Slovenia, management of patients with IEM is centralized at the University Children's Hospital, with the exception of adult patients with Fabry and Gaucher disease. The team work is well organized with close cooperation between the laboratory and pediatricians specialized in metabolic disorders. According to the known frequencies of IEM from the literature, we would expect more positive results than obtained. To evaluate these results, we are planning to perform a pilot study on expanded newborn screening.

A new analytical procedure using separation support based on Convective Interaction Media (CIM) was developed for speciation of A1 in human serum at normal concentration levels. The separation of proteins was performed on a weak anion exchange CIM diethylamine monolithic column. Isocratic elution with buffer A (0.05 M tris(hydroxymethyl)aminomethane--hydrochloric acid + 0.03 M sodium hydrogen carbonate) was applied for 5 min, followed by linear gradient elution from 100% buffer Ate 100% buffer B (buffer A + 1 M ammonium chloride) for the next 40 min. Separation of proteins was followed by UV detection at 278 nm. Separated Al species were detected online by inductively coupled plasma mass spectrometry. It was experimentally proven that 91 [+ or -] 7% of A1 in human serum was eluted under the transferrin peak. Transferrin was identified on the basis of the retention volume and by ACQUITY ultraperformance liquid chromatography--electrospray ionization mass spectrometry. The problem of extraneous contamination with A1 was successfully overcome by using efficient cleaning procedures of eluents and chromatographic supports. The efficient cleaning was of paramount importance to perform A1 speciation at extremely low concentration levels. The repeatability of measurement tested for six consecutive separations of unspiked serum was [+ or -]8.6%. The limits of detection and quantification (based on 3 and 10 s of the blank) were 0.15 and 0.49 ng [mL.sup.-1] A1 bound to transferrin, respectively. This is the first report on quantitative and reliable speciation of A1 in human serum at normal concentration levels.

Background: Short-chain acyl-CoA dehydrogenase deficiency (SCADD) is a rare inherited mitochondrial fatty acid oxidation disorder associated with variations in the ACADS (Acyl-CoA dehydrogenase, C-2 to C-3 short chain) gene. SCADD has highly variable biochemical, genetic and clinical characteristics. Phenotypes vary from fatal metabolic decompensation to asymptomatic individuals. Subject and methods: A Romani boy presented at 3 days after birth with hypoglycaemia, hypotonia and respiratory pauses with brief generalized seizures. Afterwards the failure to thrive and developmental delay were present. Organic acids analysis with gas chromatography-mass spectrometry (GS/MS) in urine and acylcarnitines analysis with liquid chromatography-tandem mass spectrometry (LC-MS/MS) in dried blood spot were measured. Deoxyribonucleic acid (DNA) was isolated from blood and polymerase chain reactions (PCRs) were performed for all exons. Sequence analysis of all exons and flanking intron sequences of ACADS gene was performed. Results: Organic acids analysis revealed increased concentration of ethylmalonic acid. Acylcarnitines analysis showed increase of butyrylcarnitine, C4-carnitine. C4-carnitine was 3.5 times above the reference range (<0.68 μmol/L). Confirmation analysis for organic acids and acylcarnitine profile was performed on the second independent sample and showed the same pattern of increased metabolites. Sequence analysis revealed 3-bp deletion at position 310-312 in homozygous state (c.310_312delGAG). Mutation was previously described as pathogenic in heterozygous state, while it is in homozygous state in our patient. Conclusions: In our case clinical features of a patient, biochemical parameters and genetic data were consistent and showed definitely SCAD deficiency. [ABSTRACT FROM AUTHOR]