UNUSUAL CASE OF THIAMINE RESPONSIVE MEGALOBLASTIC ANEMIA
Keywords:
child, diabetes, thiamine responsive megaloblastic anemia, respiratory chain deficiencyAbstract
Background: Thiamine- responsive megaloblastic anemia syndrome is a rare autosomal recessive disorder defined by the occurrence of megaloblastic anemia, diabetes mellitus, and neurosensoriel deafness, responding in varying degrees to thiamine treatment.
Aim: Report an unusual case of this rare disorder
Case report: We report the case of a four-year-old boy who presented unusual features of thiamine- responsive megaloblastic anemia. In addition to the typical triad of the syndrome, he presented leuconeutropenia, hepatosplenomegalia, cardiac abnormalities including absent P waves, mitral and tricuspid insufficiency, retinitis pigmentosa, nystagmus, developmental delay and a brain Magnetic resonance imaging ischemic lesion. Lactate levels in serum and the lactate/ pyruvate ratio were increased. The mitochondrial mutation m.3243A>G located in MTTL1 gene encoding for transfer RNA leucine (tRNALeu(UUR)) was not found . Treatment with thiamine resulted in normalisation of the haemoglobin level, white cell count, and glucose and lactate levels. On three years follow up, the patient did not need insulinotherapy.
Conclusion: These data sign the crucial role that thiamine plays for many cells and tissues and its importance in the activity of the respiratory chain.
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