ABSTRACT
La linfohistiocitosis hemofagocítica (LHH) puede ser primaria (hereditaria) o secundaria a infecciones, tumores malignos, trastornos reumatológicos, síndromes de inmunodeficiencia y metabolopatías. Se informaron casos de intolerancia a la proteína lisinúrica, deficiencia de múltiples sulfatasas, galactosemia, enfermedad de Gaucher, síndrome de Pearson y galactosialidosis. No se sabe cómo se desencadena la LHH en las metabolopatías. Se diagnosticó LHH en un lactante de 2 meses con letargo, palidez, alimentación deficiente, hepatoesplenomegalia, fiebre y pancitopenia, y se instauró el protocolo HLH-2004. Se realizaron, en conjunto, análisis para detectar mutaciones genéticas y pruebas metabólicas; los resultados fueron negativos para las mutaciones genéticas de LHH primaria, pero se detectaron hiperamoniemia y concentración elevada de metilcitrato. Se diagnosticó acidemia propiónica. Aquí informamos sobre un caso de LHH secundaria a acidemia propiónica. Es posible la realización simultánea de pruebas de detección de trastornos metabólicos y de mutaciones genéticas para el diagnóstico temprano en los lactantes con LHH
Hemophagocytic lymphohystiocytosis (HLH) may be primary (inherited/familial) or secondary to infections, malignancies, rheumatologic disorders, immune deficiency syndromes and metabolic diseases. Cases including lysinuric protein intolerance, multiple sulfatase deficiency, galactosemia, Gaucher disease, Pearson syndrome, and galactosialidosis have previously been reported. It is unclear how the metabolites trigger HLH in metabolic diseases. A 2-month-old infant with lethargy, pallor, poor feeding, hepatosplenomegaly, fever and pancytopenia, was diagnosed with HLH and the HLH-2004 treatment protocol was initiated. Analysis for primary HLH gene mutations and metabolic screening tests were performed together; primary HLH gene mutations were negative, but hyperammonemia and elevated methyl citrate were detected. Propionic acidemia was diagnosed with tandem mass spectrometry in neonatal dried blood spot. We report this case of HLH secondary to propionic acidemia. Both metabolic disorder screening tests and gene mutation analysis may be performed simultaneously especially for early diagnosis in infants presenting with HLH.
Subject(s)
Humans , Male , Infant , Lymphohistiocytosis, Hemophagocytic/diagnosis , Propionic Acidemia/diagnosis , Pancytopenia , Splenomegaly , Lymphohistiocytosis, Hemophagocytic/drug therapy , Propionic Acidemia/drug therapy , Torpor , Continuous Renal Replacement Therapy , HepatomegalyABSTRACT
RESUMEN El tamizaje neonatal de los errores innatos del metabolismo se instauró hace más de 50 años en el mundo. En Latinoamérica, Uruguay, Costa Rica, Chile, Brasil y Colombia han implementado esta política de salud pública de manera sostenida. La tecnología para detectar estas enfermedades ha ido progresando con un mejor costo/efectividad, haciendo que sea de acceso casi universal. Los trastornos del metabolismo intracelular de la cobalamina es un grupo heterogéneo clasificados en tres fenotipos bioquímicos. Reportamos al primer paciente en Perú con diagnóstico tardío de una variante homocigota c.394 C>T en el gen MMACHC, el cual pertenece al grupo de complementación cblC el cual produce aciduria metilmalónica y homocistinuria, caracterizado por talla baja, hipotonía, retraso del desarrollo psicomotor, convulsiones, anemia megaloblástica, trombocitopenia y neutropenia ondulantes; con homocisteína elevada, acidemia metilmalónica, y contradictoriamente aumento de vitamina B12 en sangre. Es importante el diagnóstico oportuno de enfermedades potencialmente tratables, evitando o disminuyendo la severidad del fenotipo, a través de la implementación de nuevas tecnologías en nuestro país.
ABSTRACT Neonatal screening for innate metabolism disorders was instituted more than 50 years ago. In Latin America, countries like Uruguay, Costa Rica, Chile, Brazil, and Colombia have implemented this public health measurement in a sustained fashion. Technology for detecting these conditions has been steadily progressing, achieving a good cost/effectiveness ratio, so access for such test is practically universal. Intracellular cobalamin metabolism disorders constitute a heterogeneous group that is subdivided in three biochemical phenotypes. We report the first patient in Peru with a late diagnosis of a homozygous c.394 C>T variant in the MMACHC gene, which belongs to the cbIC complementation group, which leads to methyl-malonic aciduria and homocystinuria, characterized by low height, retardation of psychomotor development, seizures, megaloblastic anemia, and variable thrombocytopenia and neutropenia. Also, homocysteine levels are high, there is methyl-malonic academia, and there is a paradoxical vitamin B12 increase in peripheral blood. This paper emphasizes the importance of making a timely diagnosis of potentially treatable conditions, avoiding or reducing the severity of the implied phenotype, with the implementation of new technologies in our country.
ABSTRACT
Abstract: Objective: Inborn errors of metabolism (IEM) are genetic conditions that are sometimes associated with intellectual developmental disorders (IDD). The aim of this study is to contribute to the metabolic characterization of IDD of unknown etiology in Mexico. Materials and methods: Metabolic screening using tandem mass spectrometry and fluorometry will be performed to rule out IEM. In addition, target metabolomic analysis will be done to characterize the metabolomic profile of patients with IDD. Conclusion: Identification of new metabolomic profiles associated with IDD of unknown etiology and comorbidities will contribute to the development of novel diagnostic and therapeutic schemes for the prevention and treatment of IDD in Mexico.
Resumen: Objetivo: Los errores innatos del metabolismo (EIM) son condiciones genéticas que pueden asociarse con trastornos del desarrollo intelectual (TDI). El objetivo de este estudio es contribuir a la caracterización metabólica de los pacientes con TDI de etiología desconocida. Material y métodos: Se realizará un tamiz metabólico mediante espectrometría de masas-tándem y fluorometría para descartar EIM; además, se analizará el perfil metabolómico de los pacientes con TDI. Conclusión: La identificación de perfiles metabolómicos asociados con los TDI de etiología desconocida contribuirá al desarrollo de nuevos esquemas diagnósticos y terapéuticos para la prevención y tratamiento de los TDI en México.
Subject(s)
Humans , Male , Female , Child , Adolescent , Young Adult , Metabolomics/methods , Intellectual Disability/etiology , Intellectual Disability/epidemiology , Metabolism, Inborn Errors/diagnosis , Mass Screening , Health Surveys , Tandem Mass Spectrometry , Fragile X Syndrome/diagnosis , Fragile X Syndrome/epidemiology , Mexico/epidemiologyABSTRACT
Intellectual disability is a prevalent form of cognitive impairment, affecting 2-3 percent of the general population. It is a daunting societal problem characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social and practical adaptive skills. Intellectual disability is a clinically important disorder for which the etiology and pathogenesis are still poorly understood. Moreover, although tremendous progress has been made, pharmacological intervention is still currently non-existent and therapeutic strategies remain limited. Studies in humans have a very limited capacity to explain basic mechanisms of this condition. In this sense, animal models have been invaluable in intellectual disability investigation. Certainly, a great deal of the knowledge that has improved our understanding of several pathologies has derived from appropriate animal models. Moreover, to improve human health, scientific discoveries must be translated into practical applications. Translational research specifically aims at taking basic scientific discoveries and best practices to benefit the lives of people in our communities. In this context, the challenge that basic science research needs to meet is to make use of a comparative approach to benefit the most from what each animal model can tell us. Intellectual disability results from many different genetic and environmental insults. Taken together, the present review will describe several animal models of potential intellectual disability risk factors.