RESUMO
OBJECTIVE: Thiamine (Vitamin B1) deficiency (TD), although reduced in incidence, is still seen in infants. We describe a rarely reported form of infantile TD with life-threatening pulmonary hypertensive crisis and severe encephalopathy, with dramatic response to thiamine supplementation. METHODS: Study design: Descriptive case series. Six young infants with mean age 76 days (range 1-3 months), manifesting rapidly progressive encephalopathy and cardio-pulmonary arrest were included. All infants underwent cardiac, neuroimaging and metabolic evaluations. RESULTS: All six infants had similar presentation with severe pulmonary arterial hypertension (PAH), hypotensive shock, metabolic acidosis and severe encephalopathy. All infants were exclusively breast-fed. Thiamine treatmwnt resulted in dramatic improvement in haemodynamic and neurological function in all the infants. There were no major neurological deficits on follow up. CONCLUSION: A high index of suspicion is warranted for this rarely described form of TD, as early identification helps in preventing mortality and morbidity.