From the Guidelines
The treatment for elevated Anti-Streptolysin O (ASO) titers involves addressing the underlying Group A Streptococcal infection with antibiotics, such as Penicillin V 500 mg orally twice daily for 10 days for adults, as recommended by the American Heart Association 1.
Key Considerations
- Elevated ASO titers indicate a recent or past streptococcal infection, but do not necessarily require treatment if there are no symptoms of active infection or post-streptococcal complications.
- The goal of treatment is to eradicate the bacteria and prevent complications like rheumatic fever or post-streptococcal glomerulonephritis, not to normalize the ASO titer.
- For children, the dosage of Penicillin V is typically 250 mg 2-3 times daily for 10 days, while for penicillin-allergic patients, alternatives include narrow-spectrum cephalosporins, clindamycin, azithromycin, or clarithromycin, as outlined in the treatment guidelines 1.
Treatment Options
- Penicillin V: 500 mg orally twice daily for 10 days for adults, and 250 mg 2-3 times daily for 10 days for children.
- Amoxicillin: 50 mg/kg once daily (maximum 1 g) for 10 days.
- Benzathine penicillin G: 600 000 U for patients <27 kg (60 lb), and 1 200 000 U for patients ≥27 kg (60 lb), administered intramuscularly once.
- For penicillin-allergic patients:
- Narrow-spectrum cephalosporin: variable dosage, orally, for 10 days.
- Clindamycin: 20 mg/kg per day divided in 3 doses (maximum 1.8 g/d), orally, for 10 days.
- Azithromycin: 12 mg/kg once daily (maximum 500 mg), orally, for 5 days.
- Clarithromycin: 15 mg/kg per day divided twice daily (maximum 250 mg twice daily), orally, for 10 days.
Important Notes
- ASO titers may remain elevated for weeks to months after the infection has resolved, and follow-up testing may be warranted in certain cases, particularly if there's concern for post-streptococcal complications.
- The American Heart Association recommends that physicians consider various factors when selecting a treatment regimen, including bacteriologic and clinical efficacy, ease of adherence, cost, spectrum of activity, and potential side effects 1.
From the FDA Drug Label
To reduce the development of drug-resistant bacteria and maintain the effectiveness of Penicillin V Potassium Tablets, Penicillin V Potassium for Oral Solution and other antibacterial drugs, Penicillin V Potassium Tablets, and Penicillin V Potassium for Oral Solution should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria. The following Infections will usually respond to adequate dosage of Penicillin V: Streptococcal infections (without bacteremia): Mild to moderate infections of the upper respiratory tract, scarlet fever and mild erysipelas. For the prevention of recurrence following rheumatic fever and/or chorea: Prophylaxis with oral penicillin on a continuing basis has proven effective in preventing recurrence of these conditions
The treatment for elevated Anti-Streptolysin O (ASO) titers is penicillin.
- Indications: Streptococcal infections, including those that cause elevated ASO titers.
- Dosage: Adequate dosage of Penicillin V, as determined by a healthcare professional.
- Note: The goal of treatment is to prevent recurrence of rheumatic fever and/or chorea, which can be associated with elevated ASO titers 2.
From the Research
Elevated Anti-Streptolysin O (ASO) Titers
Elevated ASO titers are indicative of a preceding Group A streptococcal (GAS) infection, which can lead to various non-suppurative diseases such as rheumatic fever and poststreptococcal glomerulonephritis 3.
Treatment for Elevated ASO Titers
The treatment for elevated ASO titers depends on the underlying condition. In cases of rheumatic fever, treatment typically involves antibiotics such as penicillin to eradicate the GAS infection, as well as anti-inflammatory medications to manage symptoms 4, 5.
Diagnostic Considerations
It's essential to note that a single ASO measurement may not be sufficient for diagnosis, and at least two sequential measurements, along with simultaneous assay for anti-DNase B, are recommended for optimal diagnosis of preceding GAS infection 3.
Clinical Implications
Elevated ASO titers can be found in various clinical conditions other than typical post-streptococcal associated diseases, and may not always be accompanied by positive culture or correlate with inflammatory parameters 6.
Differential Diagnosis
In cases of renal disease, ASO titers can be useful in differentiating between "primary" nephrotic syndrome of childhood and other conditions such as acute glomerulonephritis 7.
- Key points to consider:
- Elevated ASO titers indicate preceding GAS infection
- Treatment depends on underlying condition
- Diagnostic considerations include sequential ASO measurements and anti-DNase B assay
- Clinical implications include potential for elevated ASO titers in various clinical conditions
- Differential diagnosis is crucial in renal disease cases 4, 3, 6, 7, 5