Necrotising myositis – learnings for a plastic surgeon

BackgroundNecrotising myositis (NM) is a life-threatening emergency. Prompt treatment is associated with more favourable outcomes, but early diagnosis is challenging. The initial absence of cutaneous signs and symptoms coupled with delayed recognition commonly result in higher rates of morbidity and mortality.ObjectivesAnalyse data regarding demographics, epidemiology, aetiology, clinical manifestations, diagnosis and treatment of previously reported cases. This publication is intended for plastic surgeons in training to help them look out for this disease.Search methods/criteriaPublications reporting necrotising myositis between 1974 to January 2020 were identified from Embase, Medline All, Web of Science Core Collection, Google Scholar and Cochrane Central Register of Controlled Trial.Data collection and analysis: Identified studies were exported to an end note library. In animal studies, studies relating to statin-induced myotoxicity and auto-immune myositis were excluded. The quality of included case reports was assessed using JBI Critical Appraisal Checklist for Case Reports.Main resultsThe most common initial presentation was a few days of antecedent prodromal flu-like symptoms associated with muscle pain. The mean age was 43.3 years and 82% had no significant medical history. The most frequent misdiagnoses were muscle strain (11%), deep vein thrombosis (10%) and viral illness (9%). Seventy-four per cent of presentations were due to Group A Streptococcus infections and only 3.5% of cases were polymicrobial. The most common clinical course following the initial presentation was rapid deterioration into profound sepsis and progression into multi-organ failure. The overall mortality rate was 36.5%.ConclusionsNM is a life-threatening muscle infection. It is a diagnostic conundrum as initial presentation is often only myalgia without features of preceding trauma. We propose that a high index of suspicion and increased awareness will reduce morbidity.OtherPROSPERO (registration number CRD42018087060). Nil funding/conflict of interest.     

Diagnostic significance of the histopathology of bone marrow macrophages in forensic autopsies

Forensic pathologists often encounter autopsies that require an assessment of antemortem general conditions (e.g., infection, metabolic disorders). To establish evaluation clues for such cases, we quantitatively examined macrophages and the general pathology of bone marrow in samples from 180 forensic autopsy cases of decedents with various conditions. Hematoxylin-eosin staining, Berlin blue staining, and immunostainings for CD163, CD138, and CD61 were performed. We determined the numbers per field (density) of total macrophages, swollen macrophages, macrophages with hemophagocytosis, and hemosiderin-laden macrophages. Each density was standardized by identifying its ratio to the total number of macrophages. The decedents' background data (cause of death, other pathological findings, postmortem interval, antemortem symptoms, and presence of resuscitation) were extracted. No correlations were found between the postmortem interval and the other decedent data, indicating that these data are not affected by postmortem changes. In the group in which inflammatory disease was the cause of death, there were significant elevations in the ratio of the swollen macrophage density to total macrophages. Significantly higher ratios of the density of swollen and hemophagocytic macrophages were observed in the group in which conditions with a prolonged agonal period were the cause of death. The group with a return of spontaneous circulation to resuscitation showed a significantly higher ratio of macrophage density with hemophagocytosis. This study provides the first statistical analysis focused on bone marrow histopathology in forensic autopsies. The results will be useful for elucidating causes of death and agonal-period conditions.