Bacteriological Profiles of Post-mortem Blood Cultures and Their Relationship to the Cause of Death: A Study of 100 Autopsies.

BACKGROUND

The use of post-mortem blood culture as a diagnostic tool in medico-legal autopsies is limited. Differentiating true infection from contamination or post-mortem bacterial translocation remains a challenge. This study aimed to evaluate the bacteriological profiles of post-mortem blood cultures and their association with the cause of death.

METHODS

A cross-sectional observational study was conducted on 100 autopsy cases with unnatural causes of death and a post-mortem interval of less than 24 hours. Cases of septicaemia and putrefied bodies were excluded. Heart blood samples were collected aseptically and cultured using standard microbiological techniques. Associations between culture results and cause of death, time since death, and hospital stay were analysed using the chi-square test.

RESULTS

Of the 100 cases, 66% showed bacterial growth, while 34% were sterile. Single-organism growth was observed in 92.4% of positive cultures. The most commonly isolated organism was Klebsiella pneumoniae (42.4%), followed by Enterobacter spp. (13.6%) and Acinetobacter baumannii (13.1%). Blood cultures were positive in nearly all cases of death due to disease and in more than two-thirds of polytrauma cases. A statistically significant association was found between the cause of death and culture positivity (p = 0.043). No significant association was observed between the time from death to autopsy (p = 0.642) or the duration of hospital stay (p = 0.988).

CONCLUSION

The cause of death significantly influences post-mortem blood culture results, with higher positivity in disease-related and polytrauma deaths. Time since death and prior hospitalisation did not affect culture outcomes. Careful sampling within 24 hours can yield meaningful bacteriological findings that may aid in determining the cause of death.