A NEONATE PRESENTING WITH GRACILE SYNDROME AND BJORNSTAD PHENOTYPE ASSOCIATED WITH BCS1L MUTATION.

GRACILE Syndrome, is an autosomal recessive disease presenting with growth retardation, severe lactic acidosis, Fanconi type tubulopathy, cholestasis, iron overload and early death without any dysmorphological or neurological features. The BCSIL gene mutation is responsible for GRACILE syndrome, Bjornstad syndrome and complex III deficiency. Bjomstad syndrome is characterized by sensorineural hearing loss and abnormal flat twisted hair shafts. The case is GRACILE syndrome with Bjomstad phenotype in neonatal period due to BCSL1 gene mutation.

[GRACILE syndrome--a severe neonatal mitochondrial disorder]. / SGRACILE-oireyhtymä--vastasyntyneen vakava mitokondriotauti.

GRACILE syndrome belongs to the Finnish disease heritage, and is caused by a point mutation in the BCS1L-gene encoding a mitochondrial protein. This leads to dysfunction of the complex III in the respiratory chain. Significant fetal growth disturbance is the primary manifestation. Within the first day the newborn infant develops severe lactic acidosis. Hypoglycemia, elevated serum ferritin and conjugated bilirubin values and aminoaciduria imply mitochondrial liver disease and renal tubulopathy. In Finland, the diagnosis is based on the 232A>G mutation in the BCS1L-gene. No specific treatment is available. GRACILE syndrome leads to early death.

Lysinuric protein intolerance: reviewing concepts on a multisystem disease.

Lysinuric protein intolerance (LPI) is an inherited aminoaciduria caused by defective cationic amino acid transport at the basolateral membrane of epithelial cells in intestine and kidney. LPI is caused by mutations in the SLC7A7 gene, which encodes the y(+)LAT-1 protein, the catalytic light chain subunit of a complex belonging to the heterodimeric amino acid transporter family. LPI was initially described in Finland, but has worldwide distribution. Typically, symptoms begin after weaning with refusal of feeding, vomiting, and consequent failure to thrive. Hepatosplenomegaly, hematological anomalies, neurological involvement, including hyperammonemic coma are recurrent clinical features. Two major complications, pulmonary alveolar proteinosis and renal disease are increasingly observed in LPI patients. There is extreme variability in the clinical presentation even within individual families, frequently leading to misdiagnosis or delayed diagnosis. This condition is diagnosed by urine amino acids, showing markedly elevated excretion of lysine and other dibasic amino acids despite low plasma levels of lysine, ornithine, and arginine. The biochemical diagnosis can be uncertain, requiring confirmation by DNA testing. So far, approximately 50 different mutations have been identified in the SLC7A7 gene in a group of 142 patients from 110 independent families. No genotype-phenotype correlation could be established. Therapy requires a low protein diet, low-dose citrulline supplementation, nitrogen-scavenging compounds to prevent hyperammonemia, lysine, and carnitine supplements. Supportive therapy is available for most complications with bronchoalveolar lavage being necessary for alveolar proteinosis.

Multiple bone fracture due to Fanconi's syndrome in primary Sjögren's syndrome complicated with organizing pneumonia.

Abstract A 66-year-old woman showing renal dysfunction with elevated serum alkaline phosphatase and anti-SS-A antibody was admitted. A labial salivary gland biopsy showing infiltration of mononuclear cells and positive anti-SS-A antibody with sicca symptoms led to a diagnosis of primary Sjögren's syndrome (SS). Fanconi's syndrome was diagnosed by renal tubular acidosis along with renal glucosuria or aminoaciduria and multiple bone fractures on bone scintigraphy. Typical bilateral pulmonary shadows were confirmed as organizing pneumonia (OP) determined by the analysis of bronchoalveolar lavage fluid and transbronchial lung biopsy. A rare complication of Fanconi's syndrome with OP in SS is described.

Aminoacidurias: Clinical and molecular aspects.

Inherited aminoacidurias are caused by defective amino-acid transport through renal (reabsorption) and in many cases also small intestinal epithelia (absorption). Recently, many of the genes causing this abnormal transport have been molecularly identified. In this review, we summarize the latest findings in the clinical and molecular aspects concerning the principal aminoacidurias, cystinuria, lysinuric protein intolerance, Hartnup disorder, iminoglycinuria, and dicarboxylic aminoaciduria. Signs, symptoms, diagnosis, treatment, causative or candidate genes, functional characterization of the encoded transporters, and animal models are discussed.

The oculo-cerebral-renal syndrome of Lowe.

Clinical, light microscopical, ultrastructural, and biochemical studies were done on nerve and muscle biopsy specimens from five patients with the oculo-cerebral-renal syndrome of Lowe. Four patients were American Indians, a racial group in whom this disease has not previously been recognized. The hypotonia, areflexia, and diffuse atrophy of muscles are associated with slowed motor nerve conduction velocities, and the morphologic changes in sensory nerves are attributed to a "dying-back" phenomenon probably resulting from an unknown metabolic derangement.

2-Hydroxyglutaric aciduria: a case report on an infant with the D-isomeric form with review of the literature.

We report on an infant with D-2-hydroxyglutaric aciduria, who presented with severe seizures and developmental delay. We reviewed the literature for 2-hydroxyglutaric aciduria and found six other patients with the D-isomer and 24 patients with the L-isomer. Although the clinical spectrum of this inborn error of metabolism is variable, the clinical course of the D-form seems to be more severe than this of the L-form.

Identification of the D-enantiomer of 2-hydroxyglutaric acid in glutaric aciduria type II.

We determined the optical isomer of the 2-hydroxyglutaric acid (2HG) that was elevated in the urine of five Japanese children with a mild form of glutaric aciduria type II (GA2), caused by a deficiency of electron transfer flavoprotein (ETF) or ETF-ubiquinone oxidoreductase (ETF-QO). The D- and L-enantiomers of 2HG were separated by capillary gas chromatography with a combination of (S)-(+)-2-octanol derivatization and chromatography on a DB-1 column. The isomer that was elevated in GA2 patients was predominantly the D-enantiomer, an observation that may serve as an additional marker for the biochemical diagnosis of GA2. D-2HG dehydrogenation, but not L-2HG dehydrogenation is apparently blocked in GA2. A specific D-2HG dehydrogenase or D-2HG-CoA dehydrogenase may be metabolically linked to ETF and ETF-QO in the mitochondria.

Organic acidurias: a review. Part 2.

Laboratory findings are an essential part of the diagnostic approach to organic acidemias. In most organic acidemias, metabolism of glucose, ketone bodies, and ammonia is deranged primarily or secondarily, in addition to derangement of the acid-base balance. Hypoglycemia, lactic and/or ketoacidosis, and hyperammonemia of varying severity accompany the overt or compensated acidosis. In most instances, a definite diagnosis will be achieved by gas chromatography/mass spectrometry (GC/MS) studies of the urine. We detail the pattern of excreted organic acids in the major disorders. When the diagnosis reached by clinical and laboratory assessments is not conclusive, it must be supported by loading tests. We list the available methods of demonstrating the putative enzyme deficiency in the patient's cells and tissues. The majority of organic acidemias may be treated by limiting the source of or removing the toxic intermediary metabolite. We provide lists of available diets, supplements, and medications. In some instances, residual defective enzyme activity may be stimulated. We describe symptomatic management of the disturbed acid-base and electrolyte balance.

Iminoglycinuria: a benign type of inherited aminoaciduria.

The diagnosis of iminoglycinuria was established in two patients on the basis of increased urinary excretion of proline, hydroxyproline and glycine in the presence of normal plasma concentrations of these respective compounds. Routine metabolic screening was performed in these infants in order to find the cause for the developmental delay observed in one infant and the siblings deaths noted in the family of the other. These two patients gave further support to the previous suggestion that renal iminoglycinuria is a benign disorder with no recognizable clinical pattern. Its detection, therefore, requires screening programs or amino acid studies.

Tyrosinemia type I: a clinico-laboratory case report.

Progressive hepatocellular dysfunction in a neonate, resulting in elevated serum alpha-fetoprotein together with raised blood levels of tyrosine and methionine, a generalized amino aciduria and the absence of urinary delta-aminolevulinic acid and succinylacetone, suggests a diagnosis of tyrosinemia type Ib. Classical tyrosinemia type I arises from a deficiency of fumarylacetoacetate hydrolase while the variant tyrosinemia type Ib results from a deficiency of maleylacetoacetate isomerase.