The frequency and significance of alveolar haemosiderin-laden macrophages in sudden infant death

Abstract Alveolar haemosiderin-laden macrophages (HLMs) in histological sections of the lung represent evidence of previous pulmonary haemorrhage and in infants may be associated with features of non-accidental injury (NAI). The aim of this study is to establish the frequency of alveolar HLMs detected at post-mortem in a large series of sudden unexpected infant deaths, and to determine their clinical significance with particular regard to a possible association with NAI. A search was performed of a database of 1516 anonymised paediatric autopsies to identify all infants (