Pulmonary haemorrhage is usually secondary to a systemic disease affecting the lung with or without other organ involvement. Idiopathic pulmonary haemorrhage is a diagnosis of exclusion; as described in the literature, it is a rare disease. We report a two months old infant who presented at the Emergency Department of Sultan Qaboos University Hospital, Oman, with respiratory failure and shock secondary to an acute severe pulmonary haemorrhage. Detailed investigations for pulmonary, cardiovascular, renal and systemic inflammatory causes were negative. His clinical presentation and radiological imaging were consistent with idiopathic pulmonary haemorrhage. Treatment with corticosteroids resulted in a remarkable and fast recovery from his critical respiratory status.