Acute idiopathic pulmonary hemorrhage among infants. Recommendations from the Working Group for Investigation and Surveillance.

This report presents CDC's recommended case definitions and surveillance practices for Acute Idiopathic Pulmonary Hemorrhage (AIPH). In 1994 and 1997, CDC reported clusters of acute pulmonary hemorrhage (APH) among infants in Cleveland, Ohio. Subsequent reviews of these investigations identified shortcomings in the conduct of the studies and concluded that the investigations did not prove an association between APH among infants and exposure to molds. In response to recommendations from these reviews, with assistance of external consultants, CDC staff developed a plan to conduct surveillance for and investigation of AIPH. In developing this response, CDC recommends a definition for a clinically confirmed case of AIPH among infants on the basis of evidence of blood in the airway, age </=1 year, absence of medical conditions related to pulmonary hemorrhage, and severe acute respiratory distress or respiratory failure. CDC recommends that pediatric intensive care units (PICUs) report cases that meet the CDC case definition to state health departments. CDC staff will study the number of reported cases of AIPH among infants and also review the Cleveland and Chicago case series to determine the degree to which the present case definition applies to them. If these reviews establish that AIPH among infants is a public health problem, on the basis of its magnitude or geographic or temporal distribution, targeted case surveillance will be initiated based on the distribution of cases. CDC staff will work with state and local health departments to investigate reported clusters of cases of AIPH among infants.