No abstract

Pearson syndrome (PS) is a rare mitochondrial disorder that usually presents with transfusion-dependent macrocytic anemia, exocrine pancreatic dysfunction, and lactic acidosis. Typical bone marrow (BM) features are vacuolization in hematopoietic progenitors, hypocellularity, and ringed sideroblasts. At the neonatal age, PS may have a variable clinical onset. Moreover, there is little information about BM features at this age and the timing of their presentation. We report a neonatal case of PS that presented with refractory anemia and atypical BM features. We reviewed the BM findings in neonatal-onset PS cases to stress the importance and limitations of BM evaluation at this age.

The human HADH gene encodes the short-chain-L-3-hydroxyacyl-CoA dehydrogenase, the enzyme which catalyzes the third step of the b-oxidation of the fatty acids in the mitochondrial matrix. Loss-of-function mutations in the HADH gene lead to short-chain-L-3-hydroxyacyl-CoA dehydrogenase deficiency, an autosomal recessive genetic defect of unknown prevalence with a wide spectrum of phenotypic variability. As in other metabolic diseases, the diagnostic relevance of the biochemical evaluations, plasma acylcarnitines, and urinary organic acids, are crucially dependent on the clinical conditions of the patient during specimen collection. This paper describes the eighth patient carrying a HADH gene mutation, a new homozygous deletion c.565delG leading to an early stop codon (p.V116Wfs124X), in an infant with hyperinsulininemic hypoglycemia, displaying abnormal patterns of plasma acylcarnitines and urinary organic acids. We conclude that, when the residual catalytic activity of the mutated enzyme is seriously reduced, the biochemical hallmarks of the disease, namely plasma 3-hydroxybutyrylcarnitine and urinary 3-hydroxyglutaric acid, are invariably present.

No abstract

No abstract