Scientists Thought A Bacteria Was Harmless – They Was Wrong

X-Ray Scan Pneumonia Lung Infection
Written by admin

X-ray Scan Pneumonia Lung Infection

Scientists have discovered that one type of bacteria is not as harmless as previously thought. In fact, it can cause infections in patients with bronchiectasis, asthma, and chronic obstructive pulmonary disease (COPD).

An international study led by Singaporean scientists has discovered that bacteria previously thought to be harmless can worsen existing lung disease.

An international team of scientists discovered this. neisseria – a type of bacteria that lives in the human body – is not as harmless as previously thought. In fact, it can cause infections in patients with bronchiectasis, asthma, and chronic obstructive pulmonary disease (COPD).

In a landmark study published September 14, 2022, Cell Host and Microbe, the team showed conclusive evidence neisseria can cause disease in the lungs and is associated with worsening bronchiectasis (a type of lung disease) in patients. The scientists were led by the Singapore Nanyang Technological University (NTU Singapore).

Bronchiectasis is a long-term condition in which the airways of the lungs become abnormally enlarged for unknown reasons in up to 50 percent of Singaporean patients. The disease is up to four times more common among Asians than its Western counterparts and can also occur following recovery from tuberculosis.[1] A study conducted at Tan Tock Seng Hospital in Singapore identified 420 hospitalized bronchiectasis patients in 2017.[2] The incidence rate is 10.6 per 100,000 and increases strongly with age.

Despite its prevalence among older people, most cases of bronchiectasis have no apparent cause and the condition tends to occur spontaneously and without warning.[3]

The international team, which includes researchers and hospitals in Singapore, Malaysia, China, Australia and the United Kingdom, to solve the puzzle of why bronchiectasis worsens at a significantly higher rate in older Asian patients. (to see additional) — Led by LKCMedicine Associate Professor Sanjay Chotirmall, Provost’s Chair of Molecular Medicine matched disease and infection data from 225 bronchiectasis patients of Asian (Singapore and Malaysia) origin with those from European bronchiectasis patients.

Neisseria: it’s not so harmless after all

Duration neisseria species are well known to cause meningitis and gonorrhea, but not known to infect the lungs. Thanks to the detailed description and rigorous characterization, the research team neisseria dominated the microbiome of Asian patients with worsening bronchiectasis.

Specifically, patients with bronchiectasis were predominant in a subgroup. neisseria wanted Neisseria subflava (N. altflava), compared with patients with bronchiectasis, experienced more severe illness and recurrent infections (exacerbations) compared to patients who did not take such a high amount of medication. neisseria.

After further research using experimental cell and animal models, the research team confirmed that: N. altflava It causes cell disruption in patients with bronchiectasis with this bacterium, causing inflammation and immune dysfunction.

Neisseria in Lung Tissue

The picture shows the detection of Neisseria (N. subflava) in lung tissue taken from patients with bronchiectasis. Shown in red is the detection of N. subflava and shown in blue is the airway cell nucleus. Credits: Cell Host and Microbe

Prior to this discovery, Neisseria was not thought to be a cause of lung infection or serious illness in patients with bronchiectasis.

“Our findings reveal for the first time that worse clinical outcomes, such as higher disease severity, worse lung function, and high rates of repeated infections among bronchiectasis patients, are closely associated with Neisseria bacteria,” said lead investigator Prof Chotirmall, LKCMedicine. I think it’s important.”

“This discovery is important because it could change how we treat our patients with bronchiectasis with this bacteria. Doctors will now need to consider Neisseria as a potential ‘culprit’ in patients who have worsened despite treatment and run tests to identify people who may harbor such bacteria in their lungs. Associate Dean (Faculty) at LKCMedicine We hope that early detection will lead to personalized treatment and therefore better disease outcomes for Asian patients with this devastating disease,” said Prof Chotirmall.

This work reflects NTU’s efforts under NTU2025, its five-year strategic plan that addresses humanity’s great challenges, such as human health. The work, led by international researchers from a variety of disciplines, also highlights NTU’s strength and focus on interdisciplinary research.

Broader relevance of Neisseria

In addition to linking Neisseria and severe bronchiectasis, the NTU-led research team has found the same bacteria are present in other more common chronic respiratory conditions such as severe asthma and Chronic Obstructive Pulmonary Disease (COPD) – a condition that causes airflow obstruction and breathing-related issues. .

Using next-generation sequencing technologies, the team also tried to investigate where this bacterium might come from, and sampled high volumes of bronchiectasis patients’ homes. neisseria in your lungs. The researchers found the presence of the bacteria in the home environment, suggesting that the indoor habitat and potentially tropical climate may favor the presence of this bacteria in the Asian environment.

What is Neisseria?

this neisseria Bacterial strains are commonly identified as the cause of sexually transmitted infections such as gonorrhea, but also critically meningitis – inflammation of the fluids and membranes surrounding the brain and spinal cord. Subtypes N. altflavahowever, it is known to be found in the oral mucosa, throat and upper respiratory tract of humans without any known link to previous lung infections.

This family of bacteria has always been thought to be harmless to humans, and infections caused by them have not been described so far.

“It is encouraging to see that we are making progress in identifying the Neisseria bacterial species as the cause of the disease,” said co-author, Professor Wang De Yun, of the Department of Otolaryngology at the National University of Singapore Yong Loo Lin School of Medicine. worsening bronchiectasis, the possible culprit that was not initially considered a threat. This is a powerful reminder that we shouldn’t be too complacent when it comes to being more proactive in doing research and exploring various possibilities, because any seemingly innocent element can be a source of threat to our body and overall health.”

Co-author Andrew Tan, Associate Professor of Metabolic Disorders at LKCMedicine, said, “The reverse translation approach adopted in this study was crucial to our success. Starting at the ‘bedside’, where we examine real-life patient experiences, we worked backwards to uncover the biological process of bacteria. Thanks to the interdisciplinary nature of the study. “By interacting with members from different research disciplines, the team was able to provide an enjoyable experience while gaining a unique perspective on the disease.”

The researchers now want to do more research and clinical trials. neisseria Destroying the microbiome through the newly launched LKCMMedicine Center for Microbiome Medicine, which aims to evaluate the benefits of targeting and treating neisseria With antibiotics at first detection in hopes that it will lead to better clinical outcomes in patients with chronic respiratory conditions.

Reference: “neisseria species as pathobiont in bronchiectasis” Liang Li, Micheál Mac Aogáin, Tengfei Xu, Tavleen Kaur Jaggi, Louisa LY Chan, Jing Qu, Lan Wei, Shumin Liao, Hong Sheng Cheng, Holly R. Keir, Alison J. Dicker, Kai Sen Tan, Wang De Yun, Mariko Siyue Koh, Thun How Ong, Albert Yick Hou Lim, John A. Abisheganaden, Teck Boon Low, Tidi Maharani Hassan, Xiang Long, Peter AB Wark, Brian Oliver, Daniela I. Drautz-Moses, Stephan C. Schuster, Nguan Soon Tan, Mingliang Fang, James D. Chalmers and Sanjay H. Chotirmall, September 14, 2022, Cell Host and Microbe.
DOI: 10.1016/j.chom.2022.08.05


  1. “Trends of Bronchiectasis Among Medicare Beneficiaries in the United States, 2000 to 2007”, Amy E. Seitz, MPH; Kenneth N. Olivier, MD, MPH; Jennifer Adjemian, PhD; Steven M. Holland, MD and D. Rebecca Prevots, PhD, MPH, August 1, 2012, Available here. Chest Diary.
    DOI: 10.1378/chest.11-2209
  2. By Hwee Pin Phua, Wei-Yen Lim, Ganga Ganesan, Joanne Yoong, Kelvin Bryan Tan, John Arputhan Abisheganaden, and Albert Yick Hou Lim, “Epidemiology and economic burden of bronchiectasis requiring hospitalization in Singapore”, 12 August 2021, available ERJ Open Research.
    DOI: 10.1183/23120541.00334-2021
  3. Ravishankar Chandrasekaran, Micheál Mac Aogáin, James D. Chalmers, Stuart J. Elborn, and Sanjay H. Chotirmall, “Geographical variation of the etiology, epidemiology, and microbiology of bronchiectasis”, 22 May 2018, available BMC Lung Medicine.
    DOI: 10.1186/s12890-018-0638-0


List of collaborating institutions

  • Department of Pharmacology, School of Medicine, Southern University of Science and Technology, Shenzhen, China
  • Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
  • Lee Kong Chian College of Medicine, Nanyang Technological University, Singapore
  • Biochemical Genetics Laboratory, Department of Biochemistry, St. James Hospital, Dublin, Ireland
  • Clinical Biochemistry Unit, School of Medicine, Trinity College Dublin, Dublin, Ireland
  • School of Civil and Environmental Engineering, Nanyang Technological University, Singapore
  • Faculty of Pharmaceutical Sciences, Zhejiang University, Hangzhou, China
  • University of Dundee, Ninewells Hospital, School of Medicine, Dundee, Scotland
  • Department of Otolaryngology, Infectious Diseases Translational Research Program, Yong Loo Lin School of Medicine, National University of Singapore
  • Department of Respiratory and Intensive Care Medicine, Singapore General Hospital, Singapore
  • Tan Tock Seng Hospital, Department of Respiratory and Intensive Care Medicine, Singapore
  • Changi General Hospital, Department of Respiratory and Intensive Care Medicine, Singapore
  • Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
  • Department of Respiratory Medicine and Intensive Care, Peking University Shenzhen Hospital, Shenzhen, China
  • Priority Research Center for Healthy Lungs, Hunter Medical Research Institute, School of Medicine and Public Health, University of Newcastle, NSW, Australia
  • John Hunter Hospital, Department of Respiratory and Sleep Medicine, New Lambton Heights, NSW, Australia
  • Woolcock Institute for Medical Research, University of Sydney, Australia
  • School of Life Sciences, University of Technology Sydney, Australia
  • Singapore Center for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, Singapore
  • School of Biological Sciences, Nanyang Technological University, Singapore
  • Department of Environmental Science and Engineering, Fudan University, Shanghai, China

About the author


Leave a Comment