Medical Bulletin 25/September/2026 - Video

Here are the top medical news for today:

New Engineered Probiotic Approach Reduced Colorectal Tumors by 43% in Mice: Study

Scientists have turned a probiotic bacterium into a tiny drug-making factory that can deliver cancer treatment directly inside colorectal tumours. In a study in mice, the approach completely eliminated three out of seven treated tumours.

Published in Science Translational Medicine, the study used Escherichia coli Nissle 1917, a non-harmful probiotic bacterium. The researchers found that after being injected into mice, the bacteria largely disappeared from major organs but built up inside tumours. Within five days, more than one billion bacteria were found in each gram of tumour tissue.

The scientists then genetically modified the bacteria to produce an enzyme called cytosine deaminase. This enzyme changes 5-fluorocytosine, a relatively harmless compound, into 5-fluorouracil, a chemotherapy drug commonly used to treat colorectal cancer.

The idea was to make the chemotherapy inside the tumour instead of sending large amounts of the drug throughout the body. This could potentially reduce damage to healthy tissues.

However, the bacteria initially broke down much of the chemotherapy they produced. Researchers removed the genes responsible for this process, allowing more of the cancer-fighting drug to remain active.

The team then added two more components to the bacteria. One was designed to stimulate immune cells that attack cancer, while the other blocked PD-L1, a protein that tumours use to weaken the immune response.

The final treatment therefore combined chemotherapy with two forms of immune-based treatment. In mice with colorectal tumours, it controlled cancer better than either approach alone. Three of seven tumours completely disappeared.

The treatment also slowed the growth of untreated tumours in some mice, suggesting that it may have triggered a wider immune response against cancer.

However, this is still early research. The study was small and conducted only in mice, with treatment often delivered directly into tumours. Further studies are needed to determine whether the approach is safe and effective in humans.

REFERENCE: Yang, Z., Im, J., Chen, N., Mariuzza, D. L., de los Santos-Alexis, K., Li, F., Ballister, E. R., Ringham, O. R., Danino, T., & Arpaia, N. (2026). Engineered probiotics for tumor-targeted combination chemoimmunotherapy. Science Translational Medicine; DOI:10.1126/scitranslmed.ady2289

Multicancer Blood Screening Detects 17 Cancer Types in Major Prospective Study

A large study has found that a blood test designed to detect signals from multiple cancers can identify cancer signals across 17 broad cancer types, including ovarian, lung, breast and colorectal cancers.

Published in Nature Medicine, the prospective PATHFINDER 2 study included 35,878 adults aged 50 and older. The multicancer early detection test looks for small pieces of DNA released by cells into the bloodstream. By analysing patterns in this DNA, the test looks for changes that may indicate cancer and also estimates where the cancer may have started.

Among 32,007 participants included in the main analysis, 287 received a positive test result. Cancer was later diagnosed in 173 of these people. This gave the test a positive predictive value of 60.3%, meaning that about six in 10 people with a positive result were confirmed to have cancer.

The test had a specificity of 99.64%, meaning very few people without cancer received a positive result. Among people whose positive test was confirmed as cancer, the test correctly identified one of the two most likely locations where the cancer started in 91.3% of cases.

The study also found that 72.8% of cancers detected were types that do not currently have high-level routine screening recommendations in the United States. Among 151 participants with a newly diagnosed primary cancer detected by the test, 53% had stage 1 or 2 disease, while 70.9% had stage 1, 2 or 3 cancer.

Researchers said the findings suggest that multicancer blood tests could potentially complement existing screening methods, particularly for cancers without established screening tests.

However, the test is not a replacement for recommended cancer screening. The study had no comparison group, and its results were mainly descriptive. Randomised trials and longer follow-up are needed to determine whether using such tests routinely can improve cancer outcomes.

REFERENCE: Nabavizadeh, N., McDonnell, C., Kurbegov, D. et al. Performance and safety of a multi-cancer early detection test: the PATHFINDER 2 study. Nat Med (2026). https://doi.org/10.1038/s41591-026-04618-w

New Study Finds No Causal Association Between Prenatal Paracetamol and Neurodevelopmental Disorders

Prenatal use of paracetamol has not been shown to cause autism or attention-deficit/hyperactivity disorder (ADHD) in children, according to a new review of available scientific evidence.

Published in Developmental Medicine & Child Neurology, the umbrella review examined seven meta-analyses involving more than 3 million participants. Researchers assessed studies investigating whether children exposed to paracetamol during pregnancy had a higher risk of autism or ADHD.

When all available studies were considered, researchers found small associations between prenatal paracetamol exposure and both autism and ADHD. However, these associations became much weaker when the analysis was limited to higher-quality studies and meta-analyses.

After applying stricter quality criteria, the estimated effects moved close to no association. Researchers found no strong epidemiological evidence showing that paracetamol exposure during pregnancy causes autism or ADHD.

The findings are important because previous studies have produced conflicting results. Some have reported an increased risk, while others have found little or no association. Differences in study design and the presence of other factors may partly explain these findings.

For example, the medical conditions for which paracetamol is taken during pregnancy, including pain and fever, could themselves be associated with child health outcomes. Other factors related to pregnancy, family background and health may also influence the results.

The researchers therefore cautioned against interpreting an association found in observational studies as proof that paracetamol causes neurodevelopmental disorders.

The review does not establish that paracetamol has no risks during pregnancy, nor does it determine whether every pattern or dose of use is completely safe. Instead, it shows that current evidence does not support a causal link between prenatal paracetamol exposure and autism or ADHD.

The researchers said treatment decisions during pregnancy should continue to be based on individual medical needs and advice from healthcare professionals, rather than on claims that paracetamol causes these conditions.

REFERENCE: Tayebi‐Hillali, H., et al. (2026). Prenatal exposure to paracetamol and the risk of autism and attention‐deficit/hyperactivity disorder: An umbrella review and meta‐meta‐analysis. Developmental Medicine & Child Neurology. DOI: 10.1111/dmcn.70512

Study Links Diabetes to Changes in Kidney Function and Electrolyte Levels

People with diabetes showed differences in some kidney function and electrolyte measures compared with healthy individuals, according to a comparative study of 300 participants published in Scientific Reports.

The study included 150 people with diabetes and 150 healthy participants. Researchers compared blood levels of urea, uric acid and creatinine, along with electrolytes including sodium, potassium, calcium and chloride. They also examined whether random blood glucose levels were related to these measures.

People with diabetes had slightly higher average creatinine and urea levels than healthy participants. Mean creatinine was 0.59 in the diabetes group compared with 0.55 in the healthy group, while average urea levels were 25.47 compared with 22.25.

Differences were also found in several electrolytes. Potassium levels were slightly higher in people with diabetes, while sodium and calcium levels were slightly lower. Although these differences were statistically significant, their absolute size was relatively small, meaning statistical significance does not necessarily indicate a major clinical difference.

The researchers also found relationships between random blood glucose and some laboratory measures. Higher blood glucose was weakly associated with higher urea and lower creatinine. A stronger negative association was observed between blood glucose and sodium levels.

However, these findings do not show that changes in blood glucose directly cause kidney or electrolyte abnormalities.

Statistical analysis found that urea, uric acid, sodium and potassium were independently associated with diabetes. Higher urea and potassium were associated with greater odds of diabetes, while higher uric acid and sodium were associated with lower odds.

Researchers stressed that the study was cross-sectional, meaning the measurements were taken at one point in time. Therefore, the findings cannot establish cause and effect or determine whether diabetes caused the observed laboratory differences.

Further long-term studies are needed to understand whether these changes have meaningful clinical implications and whether kidney and electrolyte measurements could help improve monitoring of people with diabetes.

REFERENCE: Abbas AB et al. Evaluation of renal function tests and serum electrolytes in diabetic and non-diabetic individuals: a comparative cross-sectional study. Sci Rep. 2026;DOI:10.1038/s41598-026-70266-2.

Daily 100g Increase in Ultra-Processed Foods Linked to 14% Higher Heart Risk: Study

Each additional 100 grams of ultra-processed food consumed daily was associated with a 14% higher risk of cardiovascular events, according to a large review published in Family Medicine and Community Health.

Ultra-processed foods contain high amounts of sugar, salt and unhealthy fats while providing less fibre, protein, vitamins and minerals.

Researchers, including scientists from Duke-NUS Medical School in Singapore, analysed 51 studies involving more than 8.8 million participants from the Americas, Europe, Asia and Oceania. Participants were followed for periods ranging from two to 32 years.

Higher consumption of ultra-processed foods was associated with a 24% greater risk of cardiovascular events, 12% higher cancer risk and 23% higher risk of overweight or obesity.

The researchers also found associations with several other health conditions. Higher ultra-processed food intake was linked to a 24% greater risk of metabolic syndrome or diabetes, 27% higher risk of depression and anxiety, 31% higher risk of digestive diseases and 11% higher risk of high blood pressure. The risk of death from any cause was also 18% higher.

Dose-response analysis showed that every additional 100 grams of ultra-processed foods per day was associated with an 11% higher risk of high blood pressure, 4% higher cancer risk and 3% higher risk of death from any cause.

The study also found that every 10% increase in the proportion of total energy coming from ultra-processed foods was associated with a 16% higher risk of metabolic syndrome or diabetes.

Researchers said possible explanations include changes to the gut microbiome, inflammation and insulin resistance. Some compounds formed during food processing may also contribute to health risks.

However, the review was largely based on observational studies, so it cannot prove that ultra-processed foods directly cause these conditions. The researchers said replacing ultra-processed foods with minimally processed alternatives may help support chronic disease prevention.

REFERENCE: Liu, X., et al. (2026). Ultra-processed food consumption and risk of multiple chronic diseases among 8,819,894 adults from 51 prospective cohorts: a dose-response meta-analysis. Family Medicine and Community Health. DOI: 10.1136/fmch-2026-003925.