Acidemia propiónica: una causa sumamente rara de linfohistiocitosis hemofagocítica en un lactante / Propionic acidemia: an extremely rare cause of hemophagocytic lymphohistiocytosis in an infant

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.

Adult Stem Cells in Hibernation: Future Perspectives of Space Travel

Space traveling is imperative for mankind in the future. Expectedly, hibernation will become an option for space traveler to overcome the endless voyage. With regard to some of the studies pointed out that during hibernation, muscle will undergo atrophy and meantime neurogenesis will reduce, these obstacles were frequently related with stem cell regeneration. Thus, investigation on whether hibernation will lead to dysfunction of stem cell becomes an important issue. By going through four main systems in this article, such as, hematopoietic system, skeletal muscle system, central nervous system and orthopedic system, we are expecting that stem cells regeneration capacity will be affected by hibernation. To date, these researches are majorly the read-out from short term or seasonal hibernating mammals. Proposing and creating a simulated long-term hibernation animal model is turning essential for the further investigation on the effect of longer period of hibernation to human stem cells.