Pulmonary hemorrhage in deceased infants: baseline data for further study of infant mortality

Infant lung samples were obtained at autopsy by medical examiner pathologists in five areas of the United States regardless of the cause of death. Lung sections were stained with hematoxylin and eosin. Sixty cases were evaluated for the study. The four sections examined for each case were taken from the anterior and posterior aspects of the right and left upper lung lobes. Histologic sections were scored for the extent of alveolar hemorrhage using the following scoring system: 0, no hemorrhage; 1, focal hemorrhage but less than score 2; 2, patchy, focal hemorrhage not present throughout the section; 3, focal hemorrhage more extensive than score 2 but not meeting the criteria for score 4; 4, patchy focal hemorrhage distributed throughout the section; 5, more extensive hemorrhage than score 4 but not meeting the criteria for score 6; 6, diffuse hemorrhage throughout the section. Total possible scores ranged from 0 to 24. Intraalveolar hemorrhage was observed in 40 cases. Overall, the mean score for the 60 cases was 5 (range, 0-24); for the 40 cases with hemorrhage, 7 (range, 1-24). Scores were compared with other descriptive variables like cause of death; interval between onset of fatal events and death; whether resuscitation was attempted; and pulmonary macrophage counts and hemosiderin scores reported in earlier studies of the same cases. In none of the 60 cases was death attributed to pulmonary hemorrhage or hemosiderosis. Pulmonary hemorrhage tends to be common among deceased infants; more prominent when there is medical treatment or resuscitation during the agonal period; infant position may partially explain distribution of hemorrhage in lungs; postmortem interval may exacerbate pulmonary hemorrhage; and infant deaths caused by acute idiopathic pulmonary hemorrhage (AIPH) or pulmonary hemorrhage/hemosiderosis (PHH) probably are rare. Specific case definitions for AIPH and PHH are needed, along with further study of these conditions.