An Unusual Cause of Diffuse Alveolar Haemorrhage: Post-Streptococcal Glomerulonephritis or Vaping Associated Lung Injury

Diffuse alveolar haemorrhage (DAH) is associated with various clinical entities. Its connection with post-streptococcal glomerulonephritis (PSGN) is uncommon, especially in children, with only two previously reported cases. With the increased prevalence of vaping, DAH has also been described in the context of e-cigarette or vaping-associated lung injury. We present a case of DAH associated with PSGN and vaping exposure in a 14-year-old male. Two weeks after receiving penicillin for pharyngitis, he presented with acute respiratory distress and acute kidney injury, necessitating non-invasive ventilation. High-dose methylprednisolone therapy (30 mg/kg/day) was administered, considering the available evidence from uncontrolled case studies in paediatric and adult populations suggesting benefit in patients with DAH due to PSGN requiring respiratory support. He subsequently experienced rapid improvement in his respiratory and renal function. We believe DAH was due to PSGN, and that smoking cigarettes and vaping may have increased the risk of pulmonary haemorrhage in this context. We hypothesize that early steroid therapy may have been beneficial and should be considered in such patients.