Severe pulmonary arterial hypertension in congenital sideroblastic anemia from PUS1 mutation - a case report.

Background: Myopathy, lactic acidosis and inherited sideroblastic anemia (MLASA) are a group of rare intriguing disorders with wider pathophysiological implications. One of the causes of MLASA is the mutation in PUS1 gene that encodes for pseudouridine synthase. This PUS1 mutation results in MLASA in which anemia and myopathy predominate. Severe pulmonary arterial hypertension has not been previously reported in patients with PUS1 gene mutation.

Case report: A 17 year old girl with congenital sideroblastic anemia presented with worsening of breathlessness. Severe pulmonary artery hypertension was documented on investigations. A homozygous variant in exon 3 of gene PUS1,( chromosome 12:g.131932301 C > T c.430 C > T) was found on sanger sequencing.

Conclusion: We document severe pulmonary arterial hypertension in a patient of congenital sideroblastic anemia from PUS1 gene. We hypothesis that cross talk with TGFb pathways might occur in PUS1 mutation, and that might cause severe PAH. This observation might have therapeutic implications.