Natural course of untreated streptococcal pharyngitis
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Natural History and Symptoms of Untreated Streptococcal Pharyngitis
Untreated streptococcal pharyngitis, caused by Streptococcus pyogenes, typically presents with a sudden onset of sore throat, fever, chills, malaise, headache, swollen lymph nodes, and sometimes a tonsillar exudate. The illness is often self-limiting, with symptoms usually resolving within six to seven days without antibiotics, compared to two to three days with treatment 34. However, the main concern with leaving streptococcal pharyngitis untreated is not the acute symptoms, but the risk of serious complications 45.
Common and Rare Complications of Untreated Streptococcal Pharyngitis
Acute Rheumatic Fever and Post-Streptococcal Glomerulonephritis
The most well-known complications of untreated streptococcal pharyngitis are acute rheumatic fever (ARF) and post-streptococcal glomerulonephritis (PSGN). ARF can lead to heart problems, including rheumatic heart disease, while PSGN affects the kidneys. PSGN is more common in school-aged children and usually has a benign course, with over 95% of cases recovering from the acute phase. However, less than 5% may progress to rapidly progressive glomerulonephritis (RPGN), and about 1% can develop end-stage renal failure (ESRF) 245.
Other Severe and Rare Complications
Untreated streptococcal pharyngitis can also lead to other rare but serious complications. For example, pulmonary-renal syndrome (PRS), which involves both rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage, has been reported as a rare sequela with high morbidity and mortality . Additionally, cases of membranoproliferative glomerulonephritis (MPGN) and endocarditis have been documented, sometimes requiring intensive treatments such as renal replacement therapy .
Importance of Antibiotic Treatment
Antibiotic treatment, especially with penicillin, is crucial not only for reducing the duration of symptoms but also for preventing the spread of infection and the development of both suppurative (e.g., abscesses) and non-suppurative (e.g., ARF, PSGN) complications 45. Penicillin remains the first-line therapy, and its use has significantly reduced the incidence of these complications .
Conclusion
While the acute symptoms of untreated streptococcal pharyngitis often resolve on their own, the risk of serious complications—including acute rheumatic fever, post-streptococcal glomerulonephritis, and rare but severe conditions like pulmonary-renal syndrome—makes prompt antibiotic treatment essential. Early intervention not only shortens illness duration but also prevents potentially life-threatening sequelae and limits the spread of infection 1245.
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An Unusual and Missed case of Streptococcal Pharyngitis Presenting as Membranoproliferative Glomerulonephritis; case Report
Untreated streptococcal pharyngitis in children can lead to membraneoproliferative glomerulonephritis, requiring renal replacement therapy.
Streptococcal acute pharyngitis.
Streptococcus pyogenes pharyngitis is often self-limiting and treated with penicillins, cephalosporins, and macrolides.
Effect of a widespread reduction in treatment duration for group A streptococcal pharyngitis on outcomes and household transmission.
Shorter treatment durations for group A streptococcal pharyngitis resulted in no detectable change in outcomes, except for more common household transmission in those receiving no treatment.
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