- An autopsy reveals what actually causes a person to die.
- But they can also play an important role in helping us better understand a disease.
- Spotlight delves into some of the fascinating intricacies of tuberculosis-related anatomical research.
It is difficult to know how many people die from tuberculosis (TB) in South Africa each year.
Meanwhile, Stats SA's frequent mortality reports put the number at less than 30,000. Meanwhile, the World Health Organization (WHO) estimates the number to be over 50,000.
This may seem like a big contradiction at first glance, but there is a simple explanation. Stats SA's figures are based on what is written on death notices, but these notices very often do not tell the full story of what a person died of. WHO estimates are derived using mathematical modeling that triangulates estimates based on multiple data sources.
Looking at the numbers from studies that determine the cause of death (or what people actually died of) is one way to see how relying on death notifications underestimates the number of people dying from tuberculosis. These autopsy studies consistently find that many people have undiagnosed tuberculosis at the time of death, and that undiagnosed tuberculosis is often the actual cause of death.
1 review study published in the journal AIDS They concluded that “in resource-limited settings, tuberculosis accounts for approximately 40% of adult HIV/AIDS-related deaths in facilities,” and that “almost half of the disease remains undiagnosed at the time of death.” There is,” he said.
According to WHO statistics, of the 280,000 people estimated to have contracted tuberculosis in South Africa in 2022, more than 65,000 were not diagnosed with the disease.
Importance of anatomical research
Dr Muhammad Osman, Academic Portfolio Lead and Senior Lecturer in Public Health at the University of Greenwich, told Spotlight it was important to conduct anatomical studies of tuberculosis. This is because it allows us to identify tuberculosis that was not diagnosed before death, which helps us understand the pathology of tuberculosis. The real burden of disease.
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Osman said identifying tuberculosis at autopsy has significant advantages. He says that by layering health-seeking behaviors (how people visit clinics), they can identify missed opportunities in TB screening and design interventions to improve TB screening.
“We may be able to trace the contacts of the deceased's family members and provide them with tuberculosis testing and prevention, but that is not happening at the moment,” he says.
Osman and his colleagues International Journal of Infectious Diseases We investigated tuberculosis among sudden death (SUD) patients in Cape Town in 2021. They found that 6.2% of the 770 cases studied had active tuberculosis confirmed at post-mortem. Even more surprising, approximately 92% of these cases were not diagnosed with tuberculosis during their lifetime.
Osman says there has been a growing awareness of undiagnosed and untreated tuberculosis in recent years. He noted that new interventions are being implemented to improve TB testing and diagnosis, including targeted universal testing. This is an approach in which people who do not have symptoms of tuberculosis but are considered to be at high risk for tuberculosis are routinely offered tuberculosis. test.
He says risks to healthcare workers are being considered more carefully these days, highlighting the importance of protecting forensic and pathology teams. (Forensic medicine focuses on determining the cause and manner of death, whereas pathology is the study and diagnosis of disease through examination of tissue, cells, autopsy, etc.)
fill the gap
Osman said their study also identified gaps between pathology services and access to routine medical service records.
“We saw this as an essential gap to fill. Forensic/pathology services need access to routine medical services. For a limited number of fatal cases, we “We were able to match the records of the patient with those of public health clinics and hospitals, who had contact with health care providers six months before the death,” he says.
“If forensic pathologists were given full access to health records, they would know the timing of previous tuberculosis episodes and the treatment results of those episodes. “It's different in the case of tuberculosis, where the macroscopic (what we see by testing) and microscopic (what we see by histology and microbiology) findings are well documented,” Osman says.
complex illness
The study of tuberculosis is complicated because tuberculosis occurs in several successive stages and can affect different parts of the body.
Professor Surenesan Naidoo, a research pathologist at the African Health Research Institute (AHRI), told Spotlight that when people think of tuberculosis, they usually think of months of coughing, weight loss, loss of appetite, and night sweats. He said that he thinks of people who are , and maybe even vomit blood.
“But there is a progression to get there, and then generally beyond that point, clinically, there is a continuum of disease. We define this as latent TB, asymptomatic TB, active TB, We later call it cured tuberculosis,” he says.
Tuberculosis is a rapidly changing field, and a paper published last week in the medical journal Lancet proposes dividing the disease into five stages.
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Professor Naidoo said autopsies provide an opportunity to study the different stages of tuberculosis (latent, asymptomatic, active and cured), especially if the patient died from another cause. He said people could be encountered at any stage in the TB continuum, and at any point someone could be shot, stabbed or involved in a car accident.
“You (pathologists) have a unique opportunity to physically study the effects of tuberculosis on cells and tissues under a microscope rather than through imaging (X-rays),” Naidu says.
Because tuberculosis can spread anywhere, an autopsy provides an opportunity to examine tuberculosis disease not only in the lungs, but also in the brain, thyroid, kidneys, and urinary system, explains Naidoo.
“Autopsy gives us the opportunity to study tuberculosis everywhere,” he says. “Clinically, we don't examine the whole body (if a person is alive). It's not practical, feasible, or safe. But… [with an] An autopsy involves examining the entire body. We study tuberculosis comprehensively,” he says.
manner
The standard method of conducting an autopsy involves a thorough examination of the body.
Naidoo explains that the process begins with an external examination to record any visible injuries, marks, or other physical characteristics. A pelvic exam involves dissecting organs, tissues, and body cavities to identify abnormalities or signs of disease. Samples may be taken for further analysis such as toxicology tests, histology, and tuberculosis studies.
Naidoo points out that any findings from the samples must be interpreted in light of the changes that occur in the corpse.
”[In] A living person, as you know, is a living person and can do things and can see things in images (X-rays), but in the case of a dead person, the person currently has You need to explain the fact that there is. You die, and certain changes occur after death. ”
Anatomical research at UCT
Ongoing research at the University of Cape Town is investigating the role of lymph nodes in the spread or containment of tuberculosis disease by looking at tissue from deceased patients.
Much of the research on tuberculosis to date has been carried out in animals rather than humans, says Dr. Virginie Rosotto, a researcher at the South African Tuberculosis Vaccine Initiative (SATVI) and co-principal investigator of the UCT study.
“We have great studies in non-human primates and mice that try to uncover the mechanisms of disease progression. But animal models don't accurately reflect what's happening in humans. It doesn't mean that it is.
“In humans, identifying where disease can occur and understanding the immunology that is occurring in the tissues where disease commonly occurs is very complex,” she says.
“For a long time, most of these human studies were done in the blood, and it was assumed that what was happening in the blood was correlated with what was happening in the lungs.”
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This means that dissections allow researchers to directly observe lungs, brains, and other tissues in ways that are not possible in living humans.
“So the only way you can actually access the tissue is to do post-mortem studies. Post-mortem studies have been done since the early part of the last century. And they seemed like great research, but the tools today are It wasn't the same.''I think this should be brought back to the research scene. “Because by looking at the blood, we can answer all the questions we've been trying to answer about what's going on in the tissue,” she says.
“Dissection allows us to study not just the blood, but the exact part we want to study.”
Collection of samples
In collaboration with the Western Cape Forensic Pathology Department, UCT has created a post-mortem sample collection platform to support tuberculosis research.
Taking advantage of the 1959 Coroners Act, which states that people who die from unnatural causes must undergo a medico-legal investigation to determine the cause of death, Rosotto and her team set out to collect specimens. entered the scene to conduct an autopsy. They aim to perform a post-mortem within 24 hours of death.
Since the study began about eight months ago, 125 autopsies have been performed, with an agreement rate of 64%.
“I think our consent rate is incredible. We're still finalizing our findings to look at the autopsies and determine how many cases of tuberculosis we've found so far.” Rosotto says.
representative sample
Dr Laura Taylor, a forensic pathologist with the Western Cape Forensic Pathology Department, said the bodies they examine were representative of the South African population under the Unnatural Deaths Coroner's Act.
“However, they are not accurately representative of South Africa's population as a whole. Due to the prevalence of trauma and violence in the community, there are certain socio-economic groups who are more likely to die from unnatural causes. ,” she says.
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Because there is no central database, Taylor could not say how many tuberculosis patients were found among the deaths.
”[T]Although there are autopsy records and reports written for each case, there is no central database specifically for detected tuberculosis. [through] It’s an autopsy,” she says.
Forensic autopsy and other diseases
Rosotto and Naidoo share the view that if successful, anatomical studies of tuberculosis could help shed light on other diseases.
The value of this information is that people who die from tuberculosis or tuberculosis may also have other conditions, such as high blood pressure, HIV or diabetes, Naidoo said.
“All these variables can be calculated… [people] Diabetes is not the only cause. Diabetes changes the face of tuberculosis, HIV changes the face of tuberculosis, and tuberculosis similarly changes the face of these diseases. Therefore, we must pay attention to its complexity and consider all common variables, such as the association between tuberculosis and HIV.
“Studies may therefore look at HIV infection and how it affects tuberculosis and vice versa, as well as diabetes, hypertension and other non-communicable diseases,” he said. concludes.
*this article Published by Spotlight – Health journalism in the public interest.Please sign up for Spotlight Newsletter.
