A 6-year-old boy presents with wheezing and a nonproductive cough for 2 hours. He is a refugee, and thus detailed medical records are unavailable. However, his mother mentions that he has experienced recurrent episodes of wheezing from the age of 7 months onwards; for the last 2 years, these have occasionally been accompanied by cyanosis and epistaxis. He has also been persistently anemic from the age of 3 years, which was attributed to a poor diet. His surgical and family histories are unremarkable, while his development is age-appropriate, and all immunizations are up to date.

He is started on oxygen via face mask and back-to-back nebulization with salbutamol and ipratropium bromide. However, his vital parameters have continued to deteriorate. An urgent chest X-ray reveals reticular and nodular opacification of the perihilar and basal regions with sparing of the apices and costophrenic angles. An ECG is normal.