Poststreptococcal Inflammatory Syndromes (PSIS), also known as Post-Streptococcal Sequelae, encompass a range of disorders that follow an infection caused by the group A streptococcus bacteria. Strep throat is a common example of such an infection, but the impact of these bacteria can extend much further, potentially leading to serious conditions like Acute Rheumatic Fever (ARF) and Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS).
In addition to fever, PSIS can cause several other symptoms such as arthritis (joint inflammation), rashes, subcutaneous nodules (bumps under the skin), chorea (involuntary movements of the extremities), and heart disease. Symptoms typically begin two to three weeks after a strep infection. The characteristic arthritis of ARF is migratory, meaning it moves from joint to joint.
Rarer still, group A strep can enter the bloodstream and cause toxic shock syndrome, a life-threatening, overwhelming infection. These latter conditions are examples of invasive strep, meaning that the infection is in parts of the body typically free from germs. Studies suggest they seem to be on the rise after a marked reduction in their occurrence during the pandemic.
Even those who have had their tonsils removed, which decreases the likelihood of strep throat, can still experience bacterial infections in the throat. Complications such as scarlet fever can occur after a strep infection, potentially causing kidney and heart issues.
Researchers have discovered how immune cells triggered by recurrent Strep A infections enter the brain, causing inflammation that may lead to autoimmune neuropsychiatric disorders in children. This study performed in mice found that immune cells reach the brain by traveling along odor-sensing pathways.
The only way to know if your illness is strep throat or something else is to get tested at a doctor’s office with a quick throat swab. Left untreated, strep throat can cause kidney damage and scarlet fever, among other complications. Viral infections cause about 80% of sore throats, but when bacteria are the cause, it’s typically group A streptococcus.
Strep throat and other forms of bacterial pharyngitis cause a sore throat, pain with swallowing, and a red throat. Symptoms tend to be more severe with strep throat compared to viral pharyngitis, including fever, body ache, and a generally sick feeling.
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