Day: September 23, 2026

Categories : Gastrointestinal Lab Tests and ImagingTags : Leave a comment

Longer Intervals Between Colonoscopies May Be Safe

On By ModernMedia
Photo by Tima Miroshnichenko

Patients who have had high-risk polyps removed from their bowel can probably wait five years, rather than three, until their next colonoscopy without increasing their risk of colon and rectal cancer. This is shown by two new studies published in the New England Journal of Medicine, in which researchers from the Karolinska Institutet have participated. The findings, from ”Colonoscopy Intervals and Colorectal Cancer Incidence after Adenoma Removal” and “Colorectal Cancer Risk among Patients with Serrated Polyps” could reduce the number of examinations and thus the burden on both patients and the healthcare system.

Every year, around 1.9 million people worldwide are diagnosed with bowel cancer. To prevent the disease, many countries have introduced screening programmes that enable more polyps to be detected and removed before cancer develops.

However, some patients are assessed as being at increased risk of developing new polyps or cancer and are therefore recommended to undergo regular follow-up colonoscopies. These examinations are resource-intensive for the healthcare system and can be perceived as burdensome for patients.

The first results from the European Polyp Surveillance (EPoS) study, a large randomised research project on follow-up after polyp removal, are now being presented. In the EPoS II study, 10 799 patients across eight European countries who had previously had high-risk adenomas – a type of polyp – removed were followed up. Participants were randomised to undergo their first follow-up colonoscopy after either three or five years.

Low risk in both groups

After five years of follow-up, the risk of colorectal cancer was very low in both groups. Among those who waited five years for their first check-up, 0.77 per cent developed cancer, compared with 0.82 per cent among those examined after three years. Nor did the researchers observe any clear differences in how far the cancer had progressed when it was detected.

At the same time, the longer follow-up interval meant that the number of colonoscopies fell sharply. During the follow-up period, nearly 4200 fewer examinations were carried out in the group that waited five years for their first follow-up.

”More than 99 per cent of patients did not develop colorectal cancer within five years of the polyps being removed. “The results suggest that we need to reassess when these patients should be called in for their next colonoscopy,” says Hans-Olov Adami, Professor Emeritus at the Department of Medical Epidemiology and Biostatistics at Karolinska Institutet, who coordinated the Swedish part of the research project.

At the same time, the researchers are presenting results from the parallel EPoS III study, which involved 1,861 patients with so-called serrated polyps, another type of polyp that can also be a precursor to cancer. In that group, too, the risk of cancer was low. After five years, around one per cent of the participants had developed colorectal cancer and none had died from the disease.

“The low risk of cancer was observed in both patients with high-risk adenomas and those with serrated polyps. This also underlines the importance of the first colonoscopy, as the studies are based on the polyps having been detected and completely removed,” says Hans-Olov Adami.

Source: Karolinska Institutet

Categories : Respiratory DiseasesTags : Leave a comment

Testing More People with TB Symptoms is Critical to Reducing New Infections, Study Finds

On By ModernMedia
Tuberculosis bacteria. Credit: CDC

By Marcus Low for Spotlight

Many people who report with TB symptoms at South Africa’s public sector clinics do not receive TB tests. Testing more of these people is one of the most effective things we can do to reduce rates of TB disease and death, according to a major new modelling study.

While South Africa has made substantial progress against tuberculosis (TB), we are not on track to meet key targets set for 2030. This is according to a new modelling paper published in the journal Global Health Action.

TB incidence in South Africa was projected to decline by 46% by 2030, relative to a 2015 baseline. The World Health Organization (WHO) End TB target adopted by South Africa aimed at an 80% reduction in incidence. TB mortality was projected to decline by 54%, against the End TB target of 90%.

The researchers also published uncertainty intervals around these estimates. Even though these intervals are relatively wide, their upper limits are below the End TB targets, suggesting that it is unlikely that South Africa will reach the targets by 2030. The modelling however also identified interventions that could help South Africa get closer to the targets.

The new research is an extension of Thembisa, an existing mathematical model of HIV and TB in South Africa. University of Cape Town epidemiologist Dr Leigh Johnson, who is the lead author of the new study, is also the key driving force behind Thembisa.

Identifying what works

The researchers estimated which of a long list of interventions would have the greatest impact against TB. In technical terms, they looked at how varying 27 different parameters linked to TB interventions impacted projected TB incidence and mortality from 2025 to 2040 by calculating correlation coefficients (see the paper for a more nuanced explanation).

They found that the greatest reductions in TB would be achieved if a high percentage (89%) of people reporting with TB symptoms were tested using new point-of-care TB tests. This would result in a 49% reduction in average TB incidence and a 67% reduction in average TB mortality, relative to a scenario in which there are no changes to current programmes. TB symptoms include persistent cough, chest pain, night sweats, fever, and unexplained weight loss. There is good evidence that many people who report with these symptoms at clinics are not offered molecular TB tests.

The World Health Organization earlier this year recommended the use of such new point-of-care TB tests. These tests aren’t yet in general use in South Africa, although they are being evaluated in pilot projects. The new tests can be run on both sputum and tongue swabs. For now, most molecular TB tests in South Africa still involve someone producing a sputum sample – which some people struggle with – and the sample being transported to a lab for testing.

The researchers also found that high rates of door-to-door testing with the new point-of-care tests could reduce TB incidence and mortality by 38% and 49% respectively, while combining high rates of door-to-door testing and digital chest X-ray screening in asymptomatic individuals could reduce TB incidence and mortality by 17% and 21%.

Even without the new tests, there are substantial gains to be had if testing was stepped up in people with symptoms. TB incidence could be reduced by as much as 29% if the level of sputum testing in individuals seeking care for TB symptoms were increased to the upper bound considered by the researchers.

Once people have been diagnosed with TB and start taking TB treatment, they typically become non-infectious within around two weeks. Diagnosing people more quickly thus results in people remaining infectious for shorter periods, thus slowing TB transmission.

Other influential parameters identified by the researchers include the extent to which COVID-19-related behaviour changes are sustained, the rate at which people living with HIV start taking antiretroviral treatment (untreated HIV is a major driver of TB), and the combined uptake and efficacy of 3HP, a relatively new form of TB preventive therapy.

Testing is the key

“We found that the rate of testing in people seeking treatment for TB symptoms is the most important driver of future TB incidence and mortality,” wrote the authors.“This finding is not surprising given the historically low rates of TB testing. In studies of patients seeking treatment for TB symptoms in South African health facilities, the proportion who received a TB test has been highly variable, ranging from 3% to 84%, with a median of only 30%. Similarly low rates have been reported in other countries with high TB burdens.”

The study authors write that these low rates of testing reflect the non-specificity of TB symptoms and healthcare workers’ concerns about the cost and time required to collect sputum specimens and to send them to a central laboratory for molecular testing. In one South African study, they point out that 36% of all people attending clinics had symptoms suggestive of TB.

“Conducting TB testing in such a large fraction of primary care attendees may be infeasible,” they write.

“Achieving high levels of testing in people with TB symptoms could require levels of laboratory testing beyond current testing capacity. However, new point-of-care tests performed on tongue swabs or sputum present an important opportunity to increase levels of TB testing in symptomatic individuals at reduced cost, without placing additional strain on laboratories.”

In addition to reduced cost, the new point-of-care tests also offer quicker results and have lower operational requirements. The main potential benefit of these tests over existing lab tests is thus that they are likely to be used much more frequently.

Regardless of the testing platform, the study authors argue there is a need to strengthen adherence to existing guidelines for systematic testing of all patients with symptoms suggestive of TB and that we need a larger healthcare workforce dedicated to TB diagnosis, better supply chains, and better monitoring systems to identify where and why symptomatic patients are not being tested.

Disclosure: The study reported on here was supported by the Gates Foundation. Spotlight receives funding from the Gates Foundation, but is editorially independent – an independence that the editors guard jealously. Spotlight is a member of the South African Press Council.

*This article was first published by Spotlight – health journalism in the public interest. Sign up to the Spotlight newsletter.

Categories : General InterestTags : Leave a comment

This Heritage Day, Help Strengthen Blood Stocks and Leave a Lasting Legacy

On By ModernMedia

A SANBS and Round Table Southern Africa partnership has helped bring more than 600 new donors into the blood donation network

A new five-part docuseries, Tafel Toure, from Round Table Southern Africa takes viewers inside the community projects driven by its members across the country. One episode takes viewers to the SANBS donor centre in Welkom, where Round Table members see first-hand what happens when ordinary South Africans make the decision to give blood and why those donations matter to patients in need.

The episode comes at a critical time for South Africa’s blood supply, with SANBS blood stock levels having declined below five days’ cover. The blood service is urging eligible South Africans to donate and help replenish stocks, particularly as regular donations are essential to maintaining a safe and sufficient blood supply.

For Round Table member and regular blood donor Stephan Theunissen, giving blood has become part of how he contributes to his community. The documentary follows him at the SANBS donor centre in Welkom as he shares why he continues to donate and encourages others to do the same.

“Giving blood is one of the simplest ways we can make a difference in our communities. You may never know whose life your donation will touch, but knowing that something as simple as taking an hour out of your day could help someone in need is what keeps me coming back and encouraging others to donate too,” says Theunissen.

Alongside Stephan’s personal experience, SANBS Donor Relations Practitioner Bronwyn Petersen takes viewers beyond the donation chair, explaining who can donate and why different blood components are needed.

“O-negative can be given to anyone in an emergency, and plasma helps stop severe bleeding and stabilise patients in trauma. Together, they’re often the first things a hospital reaches for when every second counts, which is why we always need more donors of both,” says Bronwyn.

Viewers are taken through the donation process alongside the presenter, offering a behind-thescenes look at what happens from the moment a donor arrives at the centre to the point where their donation becomes part of the blood supply.

The episode also highlights the growing impact of the SANBS and Round Table Southern Africa partnership, which has contributed to more than 600 new donors and over 100 blood drives.

As South Africa marks Heritage Month, the partnership provides a powerful example of how community action and a shared commitment to giving back can create a lasting impact.

“Round Table Southern Africa has always believed that real impact starts when ordinary people choose to get involved. Our partnership with SANBS is a powerful example of that. Through TafelToere, we hope to not only showcase what our members are doing in their communities, but also inspire more South Africans to put up their hands, donate blood and make a difference. One donation, one hour and one decision can ultimately help save a life,” says Wessels Dreyer, incoming President of Round Table Southern Africa.

Monique Schreiner, Senior Manager: Donor Relations at the South African National Blood Service, says the partnership demonstrates how community-driven action can help strengthen the country’s blood supply.

“We have fallen below five days’ blood stock cover, and this is a critical reminder of why regular blood donation matters. Every day, patients across South Africa rely on blood and blood products for emergency care, surgery and ongoing medical treatment. Partnerships such as the one with Round Table Southern Africa help us reach new donors and show people the real impact of their decision to donate,” says Schreiner.

She adds that the documentary offers viewers a behind-the-scenes look and builds greater understanding of the blood donation journey.

“Blood donation is a powerful example of how an individual act can have a far-reaching impact. Through this documentary, we have an opportunity to show people what happens behind the scenes and remind eligible South Africans that their decision to donate can help ensure blood is available when a patient needs it most.”

For Round Table, the episode is an opportunity to encourage more young men to see blood donation as a simple but meaningful way to contribute to their communities. The call, however, extends beyond Round Table’s membership, with eligible first-time, regular and lapsed donors all encouraged to play their part in maintaining South Africa’s blood supply

.Watch the Round Table Southern Africa docuseries, Tafel Toure, and follow Stephan Theunissen and the SANBS team as they take viewers behind the scenes of blood donation.

Categories : AllergiesTags : Leave a comment

Neuron Memory: Why Repeated Exposures Worsen Allergies

On By ModernMedia

A new preclinical study led by investigators from Mass General Brigham offers a potential explanation for two longstanding questions in allergy: Why do allergies often emerge only after repeated exposure, and why do people with one allergy frequently develop others? The findings are published in Immunity.

The team’s earlier work revealed that sensory neurons can directly sense certain allergens and help start the allergic immune response. The new study shows that these neurons do not simply detect allergens in the moment but can retain a metabolically encoded record of previous exposures that allows them to respond more strongly to later exposures, even after the original allergen is gone.

“Now that we know what may cause people to become allergic and pick up more sensitivities, we can design ways to stop it from happening,” said senior author Caroline L. Sokol, MD, PhD, a physician-scientist at Mass General Brigham.

“What is especially encouraging is that allergic memory in neurons faded with time in our models,” Sokol said. “We are now investigating whether we can deliberately reset this memory, which could ultimately offer a way to reduce the risk of developing allergies.”

The study grew from a familiar clinical observation – people tend to encounter the same pollen, pets or foods repeatedly before developing an allergy. Drawing on her perspective as a clinician, scientist and allergy sufferer, Sokol wondered whether the nervous system might help explain this delay.

“Neurons are known for their ability to form memories,” Sokol said. “We asked whether an initial allergen exposure might leave a trace – not enough on its own to trigger a full allergic response, but enough to prime the neurons to respond more strongly the next time.”

To test this idea, the researchers modelled recurrent allergen exposure in mice and found that an initial exposure activates a specific signaling pathway in neurons. This pathway not only primes them to later respond to the same allergen, as the team hypothesized, but also to other allergens that share the same enzymatic activity but have different molecular structures.

This suggests that sensory neurons may remember a shared feature of allergens rather than their precise molecular identity. This cross-allergen response may help explain why developing sensitivity to one allergen can increase susceptibility to others.

Source: Brigham and Women’s Hospital