New research presented at the virtual European Respiratory Society International Congress revealed having fewer fungi types in the lungs is linked to increased severity of disease in acute respiratory distress syndrome (ARDS) patients. According to the study, fungi activates and regulates the immune system.
What is ARDS?
Acute respiratory distress syndrome (ARDS) is an acute diffuse inflammatory process in the lungs due to various infectious and non-infectious conditions. It is characterized by damage to the pulmonary epithelial cells, with subsequent alveolar-capillary leak and exudative pulmonary edema.
ARDS is associated with COVID-19. Routinely, patients with ARDS require oxygen therapy to provide them with breathing support.
The Human Microbiome
A diverse microbial flora is associated with every human being’s skin and mucous membranes from shortly after birth until death. The human body, which contains about 30 trillion cells, routinely harbors about 10 trillion bacteria. Fungi do makeup part of our normal flora. For example, Candida species are common fungi that are normal flora on our skin and our respiratory, genital, and digestive tracts.
Noel Britton, a Ph.D. candidate at the University of Pittsburgh, said that the study was done in over 200 patients between October 2011 and September 2019 and then carried on into the pandemic with COVID-19 patients. 21% of all participants had ARDS, with 61% being women. The researchers collected mucus-based secretions from the trachea (the main airway leading down to the lungs) and extracted DNA for Next-generation sequencing.
“We identified about 100 different types of fungi in the lungs of mechanically-ventilated, critically ill patients. The diversity was quite low in all samples, but in samples in which a single species dominated, the diversity was very low. Many patients had samples that were dominated by a single fungal species from the Candida type; this made up more than 50% of the fungi present in these samples, and it is known to be involved in causing disease in humans.” she said.
ARDS patients had lower fungal diversity than those without the disease. This observation was closely related to shock, sepsis, and organ failure. Decreased diversity was linked with worse injury to the lungs, more intensive treatment, and elevated levels of a protein called pentraxin-3, an indicator of inflammation and disease severity.
ARDS continues to be associated with a high mortality rate. As we speak, there’s no known cure for ARDS. Patients are only accorded supportive care which includes mechanical ventilation. However, with the current findings, there is hope for the discovery of a possible diagnostic tool and cure.