Severe Respiratory Distress in a Child with Pulmonary Idiopathic Hemosiderosis Initially Presenting with Iron-Deficiency Anemia.

Idiopathic pulmonary hemosiderosis (IPH) is a rare cause of alveolar hemorrhage in children but should be considered in children with anemia of unknown origin who develop respiratory complications. It is commonly characterized by the triad of recurrent hemoptysis, diffuse parenchymal infiltrates, and iron-deficiency anemia. Pathogenesis is unclear and diagnosis may be difficult along with a variable clinical course. A 6-year-old boy was admitted to the hospital with a severe iron-deficiency anemia, but he later developed severe acute respiratory failure and hemoptysis requiring intubation and mechanical ventilation. The suspicion of IPH led to the use of immunosuppressive therapy with high dose of corticosteroids with rapid improvement in clinical condition and discharge from hospital.

Fabry disease: polymorphic haplotypes and a novel missense mutation in the GLA gene.

Fabry disease: polymorphic haplotypes and a novel missense mutation in the GLA gene. Fabry disease (FD) is an X-linked lysosomal storage disorder with a heterogeneous spectrum of clinical manifestations that are caused by the deficiency of α-galactosidase A (α-Gal-A) activity. Although useful for diagnosis in males, enzyme activity is not a reliable biochemical marker in heterozygous females due to random X-chromosome inactivation, thus rendering DNA sequencing of the α-Gal-A gene, alpha-galactosidase gene (GLA), the most reliable test for the confirmation of diagnosis in females. The spectrum of GLA mutations is highly heterogeneous. Many polymorphic GLA variants have been described, but it is unclear if haplotypes formed by combinations of such variants correlate with FD, thus complicating molecular diagnosis in females with normal α-Gal-A activity. We tested 67 female probands with clinical manifestations that may be associated with FD and 110 control males with normal α-Gal-A activity. Five different combinations of GLA polymorphic variants were identified in 14 of the 67 females, whereas clearcut pathogenetic alterations, p.Met51Ile and p.Met290Leu, were identified in two cases. The latter has not been reported so far, and both mutant forms were found to be responsive to the pharmacological chaperone deoxygalactonojirimycin (DGJ; migalastat hydrochloride). Analysis of the male control population, as well as male relatives of a suspected FD female proband, permitted the identification of seven different GLA gene haplotypes in strong linkage disequilibrium. The identification of haplotypes in control males provides evidence against their involvement in the development of FD phenotypic manifestations.

Functional studies of new GLA gene mutations leading to conformational Fabry disease.

Fabry Disease (FD) is an X-linked multisystemic lysosomal disorder caused by mutations of alpha-galactosidase (GLA) gene. Only a few of the 450 genetic lesions identified so far have been characterised by in vitro expression studies. Thus the significance of newly identified GLA nucleotide variants in FD patients which lead to alpha-galactosidase (GAL-A) amino acid substitutions or intronic changes can be uncertain. We identified three GLA mutations, c.155G>A (p.C52Y), c.548G>C (p.G183A), c.647A>G (p.Y216C) in as many individuals (two male; one female) and performed in vitro expression studies and Western blot analysis in order to clarify their functional effects. Reduced GAL-A activity and normal or partially reduced mutant proteins were present in all overexpressed mutant systems in which three-dimensional structural analysis showed that the active site was not directly involved. We hypothesize that the three new mutations affect the GAL-A protein, leading to conformational FD. When mutant proteins overexpressed in COS-1 cells and in patients' lymphocytes were tested in the presence of the 1-deoxygalactonojirimicin (DGJ) chaperone, the p.G183A and p.Y216C systems showed increased GAL-A enzyme activities and protein stabilisation while p.C52Y was not responsive. We underline that genetic, biochemical and functional studies are helpful in clarifying the consequences of the missense genetic lesions detected in FD. ERT is the elective therapy for Fabry patients, but it is not always possible to issue the enzyme's active form in all involved organs. Our study endorses the hypothesis that an active site-specific chemical chaperone, which could be administered orally, might be effective in treating GAL-A conformational defects.

Type II sialidosis: review of the clinical spectrum and identification of a new splicing defect with chitotriosidase assessment in two patients.

Sialidosis is a lysosomal storage disease caused by the deficiency of alpha-N-acetyl neuraminidase-1 (NEU1). Sialidosis is classified into two main clinical variants: Type I, the milder form of the disease, and Type II, which can in turn be subdivided into three forms: congenital, infantile and juvenile. We report herein the clinical, biochemical and molecular characterisation of two patients with Type II sialidosis exhibiting the congenital (P1) and infantile forms (P2). We also review clinical data on the rare Type II forms of sialidosis in the hope of improving understanding of the disorder and facilitating its diagnosis. The genetic characterization of the two patients showed one known [c. 679G > A (p.G227R)] NEU1 missense mutation (detected in P2), and the new c.807 + 1G > A splicing defect (detected in P1), a genetic lesion that is extremely rare in this disease. Interestingly, P2 presented an extremely elevated level of chitotriosidase in plasma. This is the first pathological detection of chitotriosidase in sialidosis patients.

Insulin-resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias.

BACKGROUND: Insulin-resistant hyperglycaemia may occasionally complicate the clinical course of organic acidaemias. STUDY DESIGN: Clinical observation. RESULTS: Two term infants, one suffering from acute early-onset methylmalonic acidaemia, the other suffering from acute early-onset propionic acidaemia, presented acutely with dehydration, ketoacidosis, and hyperammonaemia. Urinary organic acid, plasma amino acids, and blood and plasma acylcarnitine analysis allowed the diagnosis of methylmalonic and propionic acidaemias. The detection of the novel c.481G>A (p.Gly161Arg) and the known c.655A>T (p.Asn219Tyr) MUT gene mutations identified the first patient as affected by methylmalonic acidaemia mut type. The high increase of propionylcarnitine after carnitine administration in both patients suggested a greatly elevated metabolic intoxication. Both newborns showed insulin-resistant hyperglycaemia. Patient 1 died, but patient 2, after a strong reduction of glucose administration, survived. To our knowledge, this is the only patient with this complication who survived. CONCLUSION: Insulin-resistant hyperglycaemia complicating neonatal onset of methylmalonic and propionic acidaemias is probably a marker of a serious disease. One patient with this complication survived after a strong reduction of glucose administration. Even if this is probably only a partial intervention, we hypothesize that in this situation a reduction of glucose administration can reduce almost the risk of persistent hyperglycaemia. Further studies are required to confirm our hypothesis.

Hypocitrullinemia in expanded newborn screening by LC-MS/MS is not a reliable marker for ornithine transcarbamylase deficiency.

In an expanded newborn screening program for inborn errors of metabolism by LC-MS/MS in Tuscany, six newborns out of 169,000 showed decreased blood citrulline levels. In one of them, molecular analysis of the OTC gene identified the known p.Trp265Leu mutation, which is correlated with late-onset ornithine transcarbamylase deficiency (OTCD). Hypocitrullinemia is not a reliable marker for OTCD newborn screening, especially for late-onset forms that may exhibit normal citrulline levels. However, when hypocitrullinemia is detected in a newborn in whom intestinal dysfunction and prematurity have been excluded, OTCD should be investigated first because of the OTCD incidence (1:14,000) and the small size of the OTC gene coding sequence.

Genetic and biochemical approach to early prenatal diagnosis in a family with mut methylmalonic aciduria.

Genetic and biochemical prenatal diagnosis was performed at 11 weeks of gestation in a family with a proband affected by mut methylmalonic aciduria (MMA) and homozygotes for the MUT gene c.643G>A (p.Gly215Ser) mutation. Both chorionic villus and amniotic fluid samples were used. The presence of high levels of methylmalonic acid and propionylcarnitine determined by gas chromatography/mass spectrometry and LC/MS/MS analysis, respectively, and the identification of the p.Gly215Ser at a homozygous level in foetal DNA allowed a certain, rapid and early diagnosis. To our knowledge, this is the first mut MMA prenatal diagnosis carried out by genetic and biochemical approach.

Mutational spectrum in ten Italian patients affected by methylmalonyl-CoA mutase deficiency.

We report seven novel mutations, including three amino acids substitutions (p.Glu286Lys, p.Cys560Tyr, p.Pro615Leu), two nonsense mutations (p.Arg31X, p.Glu 451X), one splicing defect (c.2125-1G >A), one small deletion (c.1758-1759delA) and nine previously described mutations identified in 10 unrelated Italian patients affected by mut MMA.

[Therapeutic objectives and strategies in NBIA 1 (Hallovorden-Spatz syndrome)]. / Obiettivi terapeutici raggiungibili e strategie terapeutiche utilizzabili, nella NBIA 1 (s. di Hallervorden-Spatz).

A 10 years old male patient, DG, was admitted in the ICU because of continuous uncontrolled movements due to a neurologycal degenerative disease (Hallervorden-Spatz syndrome) able to determine reduction of spontaneous breathing efficacy. At admission he presented acute ventilatory failure, because of a Staphylococcus aureus broncopneumonia, so he had a tracheal tube and mechanical ventilation (pressure support). During hospitalization (4 months in ICU and 2 months in Pediatric Department) DG received tracheotomy and percutaneous gastrostomy, to obtain adequate spontaneous ventilation and artificial enteral nutrition; a satisfactory pharmacological control of choreo-athetosic movements, with not great interference with original sleep-awake cycle, was obtained. Actually DG is living in his family (9 months follow-up); he has tracheotomy and percutaneous gastrostomy; he can relate with the environment; in a few months, he'll go to school again. He need 30 daily administrations of 8 different drugs; family, supported by an integrated multidisciplinary équipe, takes care of him. The role of Intensivist is essential not only in the management of acute phases in chronic diseases, but also in the longterm management of a homely care.