Medical Bulletin 21/ February/ 2025 - Video

Swimming in some lakes with still water can lead to infection with Legionella, bacteria that can cause pneumonia, and people who engage in open water swimming should be aware of this risk, reveals a practice article published in the Canadian Medical Association Journal.

“Legionella infection represents a public health hazard owing to its ability to spread through exposure to natural water bodies and human-made water reservoirs,” writes Dr. Ashley Bryson, an internal medicine resident at the University of Manitoba, with coauthors.

Legionella infection is an atypical cause of community-acquired pneumonia. Referred to as legionnaires’ disease, it presents with fever, fatigue, respiratory symptoms, and sometimes diarrhea. Legionella bacteria thrive in the warm, stagnant water in plumbing systems, air conditioners, public spas, and even lakes and rivers. Risk factors for legionnaires’ disease include age older than 50 years, smoking history, chronic cardiovascular or kidney disease, diabetes, and a compromised immune system.

Fewer than 100 cases of legionnaires’ disease are reported per year but, as diagnosis is challenging, cases may be underreported.

“Clinicians should consider legionnaires’ disease in patients with pneumonia that does not improve despite the use of broad-spectrum antibiotics, especially if the pneumonia is severe, occurring in immunocompromised patients or patients with recent travel history, or when only antimicrobials without activity against atypical pathogens have been administered,” the authors recommend.

Ref: Ashley Bryson, Martha Shepertycky, Terence Wuerz and Philippe Lagacé-Wiens; Legionnaires’ disease following lake swimming in Iowa: CMAJ February 18, 2025 197 (6) E155-E158; DOI: https://doi.org/10.1503/cmaj.241086

Chronic obstructive pulmonary disease (COPD) is an inflammatory disease characterized by airway obstruction and loss of alveolar surface, together resulting in progressive and irreversible airflow limitations and shortage of breath. Chronic bronchitis and emphysema are two major phenotypes of the disease. Cigarette smoke (CS) is a long-known cause of COPD, and it accounts for more than 70% of COPD cases, as reported by WHO,1 but the contribution of indoor and outdoor air pollution is increasingly acknowledged.

By analyzing multiple emphysema and COPD patient datasets, SPP1 is significantly upregulated in the lungs of patients, compared to healthy individuals. “These findings pointed out the clinical relevance of SPP1 induction during COPD development and has motivated us to understand their contributions in depth,” Dr. Lianyong Han, the lead author of the study says.

In an experimental COPD model, Dr. Han has identified a sub-population of macrophages in the lung expressing high level of Spp1, and long-term cigarette smoking exposure caused persistent induction of Spp1 up to 6 months in these macrophages (Spp1+ macrophages). This finding is supported by advanced high-throughput single-cell RNA sequencing technique.

Similar to cigarette smoking, soot-like carbonaceous particles also caused long-term induction of Spp1, as well as the release of Osteopontin (OPN), a protein encoded by Spp1. “Consistently, OPN is also localized in macrophages in the lung, as revealed by our immunohistochemical staining,” Dr. Han says.

This study reveals a crucial mediator to environmental particle pollution-related chronic lung disease development and provides a potential preventive target.

Ref: Lianyong Han, Verena Haefner, Ali Önder Yildirim, Heiko Adler, Tobias Stoeger; Carbonaceous particle exposure triggered accumulation of Osteopontin/SPP1+ macrophages contributes to emphysema development: MedComm, Vol 6(2).

https://doi.org/10.1002/mco2.70061

With New Year resolutions in full swing and health tracking apps at our fingertips, new research reveals concerning links between health and fitness apps and disordered eating, body image concerns and excessive exercise.

“Diet and fitness apps are marketed as tools to improve health, however they may also have unintended negative consequences, such as creating pressure to meet goals, concerns about body image as well as provoking feelings of guilt if goals aren’t achieved,” says Ms Isabella Anderberg in the College of Education, Psychology and Social Work.

The use of diet and fitness apps is common among young adults, with an estimated 311 million people using health apps to track their meals, calories, and exercise.

Flinders University researchers reviewed 38 studies to examine the links between the use of diet and fitness apps and the risk of users becoming obsessive about weight loss, body image, calorie counting, and excessive exercise.

The research found that those who use health and fitness apps regularly were more likely to have problematic habits related to food and exercise.

“We found that young adults who use diet and fitness apps have greater disordered eating symptoms, such as harmful or restrictive diets, and have negative thoughts about body image when compared to those that don’t use them,” says Ms Anderberg.

The research also highlights the responsibility that app developers have when designing health and fitness apps to consider the psychological impacts of these tools.

The research team noted that more research is needed to understand the benefits and risks related to using health and fitness apps.

“As self-monitoring technology evolves and new diet and fitness apps are released, it is crucial that research continues to explore potential benefits and any unintended consequences connected to their use,” concludes Ms Anderberg.

Ref: , “The link between the use of diet and fitness monitoring apps, body image and disordered eating symptomology: A systematic review” by Isabella Anderberg, Eva Kemps and Ivanka Prichard was published in Body Image journal. DOI: 10.1016/j.bodyim.2024.101836

Pharmacogenomics – an individual’s genetic response to medications – is an increasingly important strand of personalised healthcare but little is known about the public's views on it.

New research shows almost 90% of people in England would agree to genetic testing to get the most effective medication and reduce the risk of side effects.

How a person responds to medication is sometimes influenced by their genetic makeup. Some medications do not work as well for people with certain genetic variations, and in other cases can lead to serious side effects. To gauge the public's attitudes on pharmacogenetics, a research team, led by Dr Emma Magavern at Queen Mary University of London in collaboration with the National Centre for Social Research (NatCen), surveyed a representative sample of UK adults.

The key findings from the survey stated that only half of participants knew that variations in DNA can predict either efficacy or side effects from a medication, people who were prescribed medication were almost twice as likely to want a PGx test and most people (59%) reported experiencing either no benefit or a side effect from a medication.

Dr Emma Magavern, NIHR Clinical Academic Lecturer in Queen Mary’s Centre for Clinical Pharmacology and Precision Medicine who led the study, said: “This survey shows that many people in the UK feel that they have taken medication which has not been good for them, and most understand that people can respond differently to the same medication. There is widespread public support for personalising prescribing with genetic information and including this within NHS clinical care nationally, in partnership with patients and highlighting the key role of patient agency.”

Ref: Emma F Magavern, A United Kingdom Nationally Representative Survey of Public Attitudes Towards Pharmacogenomics: QJM