AUTHORS' CHRONICLES

Prevalence of tuberculosis in medicolegal autopsies

Prevalencia de tuberculosis en autopsias forenses

Mitul M. Sangma¹

1 Regional Institute of Medical Sciences, Imphal, India

Mitul M. Sangma describes for SIIC his article published in Journal of Medical Society 28(3):162-165, Sep 2014.

Imphal, India (special for SIIC)

Tuberculosis (TB) is a health problem across the world. In developed countries, the morbidity and mortality associated with TB have decreased, whereas it is still in a problem in developing countries. Most cases of TB are pulmonary and acquired by person to person transmission of air-borne droplets of organisms. In medicolegal autopsies, most of the cases are with unknown history and the risks of infection with TB from these bodies do exist. The present study was undertaken to find out the prevalence of TB in medicolegal autopsy cases. In a tertiary health care teaching hospital at northeast India, a retrospective study was conducted on the cases brought for medico legal autopsy from 2003 to 2012 (ten years period). A detailed history of the cases along with the demographic profiles of the cases, and the findings during autopsy were recorded. Those cases with granulomatous inflammation with caseation necrosis on examination of the tissue samples stained with haematoxylin and eosin (H and E) stain were termed 'Active TB'; and cases with fibrosis and calcification of the lung were termed 'suspicious cases of inactive TB'. The findings were recorded and statistically analysed. On analysis of the findings, it was observed that out of the total 4415 autopsy cases, 74 cases (1.7%) had findings of TB. The highest number of tuberculosis cases was observed in males in the age groups of 40 to 50 years (32.43%) followed 50 years and above (25.67%). TB, as to be the primary cause of death was observed in 28.38% of the cases, of which 22.97% were pulmonary while 5.41% were cases of disseminated/extrapulmonary TB. In the lung, active TB was observed in 34.28% i.e., granulomatous inflammation with caseation necrosis (27.14%), or granulomatous inflammation with caseation necrosis and tubercular pneumonia (7.14%). Suspicious cases of inactive TB, i.e., fibrosis and calcification were observed in 65.71%. Tuberculosis affects the lungs but can affect other sites as well. An autopsy is an exceptionally efficient method of transmitting TB from the dead body to those present in the autopsy room. Exposures as brief as 10 minutes in the autopsy room have resulted in transmission. At the same time, it has been documented that autopsy exposure is far more infectious than exposure during life and it is not unusual for TB to remain undetected until a patient dies. The frequency of active TB was 1.9% and that 70% of those cases were diagnosed only at autopsy in a study. In our study, 1.7% of the cases had TB and these cases were diagnosed only during autopsy. Clinically unrecognized active TB occurred more often in men than women, especially in younger age-groups, and this may reflect everyday life habits, especially consumption of tobacco and alcohol, or difficult job conditions such as working outdoors or in poorly ventilated spaces. However, according to a study by Garg M, active TB today is a disease of elderly and is attributable mainly to recurrence of dormant infection and decrease in the immune status of elderly. In our study also most of the cases belonged to the older age group. In India, out of the 300 million people infected with mycobacterium TB, 12 million are constituted by cases with active TB. Although TB can affect any organ, 70%-80% cases suffer from pulmonary TB. In the present study, 22.97% of the cases had pulmonary tuberculosis as the primary cause of death while 5.41% of the cases died due to disseminated/extrapulmonary tuberculosis. There are people who do not seek medical attention and these cases pose as a threat to the medical workers and mortuary staff. In forensic practice, most of the cases are brought without any known history and the danger of transmission of such diseases to the mortuary workers is high. The group at higher risk include autopsy workers and persons involved in histopathological preparation from fresh materials. Moreover, most of the mortuary staffs do not understand the problem of bacterial contamination of the autopsy room and they face dangers of exposure to such risks. Instances of TB outbreaks caused by multidrug-resistant Mycobacterium tuberculosis have increased and this is indeed a matter of concern for autopsy workers. The finding of TB in forensic autopsy cases in this study highlights that there are undiagnosed cases of active TB who are not seeking proper medical attention. A strict implementation of safe procedure for high-risk autopsies is recommended.