Post-mortem microbiology (PMM) as diagnostic tool in sudden unexpected childhood deaths

Post-mortem microbiology (PMM) is a significant diagnostic tool to identify infectious agents, unfortunately not always applied in forensic context. Two cases of meningo-encephalitis in juvenile females are reported. The first case involved an 8-year-old girl found dead in her bed, after a three-months clinical history of shortness of breath, coughing, vomiting, headache and purulent discharge from the ear canal. A diagnosis of adenoidal hypertrophy was made by pediatricians. At autopsy, acute and chronic multifocal inflammatory infiltrates were found at the brain, lungs, thymus and adenoidal tissue. The microbiological analysis performed on cerebrospinal fluid (CSF) was positive for Human Herpesvirus 6 (HHV-6). The cause of death was assessed as meningo-encephalitis based both on histological findings and PMM results. Based on the clinical history, medical malpractice issues were assessed. The second case is related to an 11-year-old girl's death, who showed a rapid neurological decline with cerebral edema and decompressive craniotomy, after a prompt diagnosis of otitis media and mastoiditis. Microbiological tests performed on samples taken before death and on formalin-fixed tissues taken after death, showed negative results. The cause of death was assessed as acute meningo-encephalitis based on the histological findings. They were mostly represented by wide inflammatory infiltrates within the cerebral parenchyma and subpial regions. Comparison of these two cases shows the strengths and limitations of PMM in the identification of the etiological agents. This issue can be crucial in the evaluation of infectious diseases and medical malpractice. In this regard, a reliable PMM requires that recommended sampling protocols be applied to biological fluids and soft tissues.