Acute idiopathic pulmonary hemorrhage in infants (AIPHI) is a rare and quite low-described entity. Nowadays, pathophysiological mechanisms are poorly understood, although the lethality remains high. We present an autopsy case report of a 2-day-old male who developed respiratory distress and blood leakage from the endotracheal tube (ET) and suddenly died because of acute pulmonary hemorrhage. A postmortem examination and histological analysis were performed and are reported in this paper. Alveolar spaces were filled with red blood cells and hyaline membranes in all the examined samples. The absence of other findings led us to select a post-mortem diagnosis of AIPHI. To support our diagnosis, we conducted a systematic review of the updated scientific literature and found that only 61 cases have been reported. Most of them presented acute respiratory distress and bleeding from the upper airways with blood leakage from ET (9.83%), hemoptysis (52.45%), epistaxis (8.2%), and hematemesis (3.27%). The autopsy data revealed hemorrhages of the lower airways and hemosiderin-laden macrophages. The data from the scientific publications and our findings are essential to achieving a correct diagnosis. On these bases, we suggest autoptic criteria to achieve a post-mortem diagnosis of AIPHI.
Keywords: acute idiopathic pulmonary hemorrhage in infants (AIPHI); autopsy; case report; forensic; lung histology; postmortem; pulmonary hemorrhage; sudden infant death syndrome.