pneumolysin

bacterial toxin

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Last updated

July 17, 2026

Quick Summary

Pneumolysin is a toxin produced by Streptococcus pneumoniae, a bacterium commonly found in the upper respiratory tract. This bacterium is a frequent cause of pneumonia, sinusitis, and meningitis. Pneumolysin plays a role in the severity of pneumonia by damaging blood vessels in the lungs, which can lead to bleeding. Antibiotics used to treat Streptococcus pneumoniae infections can sometimes worsen lung damage by causing the bacteria to break open and release more pneumolysin. Research is ongoing to find ways to counteract this effect.12

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pneumonia
Bacterial pneumonia
…bacteria release a toxin called pneumolysin that damages the blood vessels in the lungs, causing bleeding into the air spaces. Antibiotics may exacerbate lung damage because they are designed to kill the bacteria by breaking them open, which leads to the further release of pneumolysin. Research into the development of…
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…bacteria release a toxin called pneumolysin that damages the blood vessels in the lungs, causing bleeding into the air spaces. Antibiotics may exacerbate lung damage because they are designed to kill the bacteria by breaking them open, which leads to the further release of pneumolysin. Research into the development of…
Read More