What antibiotics (abx) would be used for Streptococcus pneumoniae infection?

From the Guidelines

For Streptococcus pneumoniae infection, the first-line antibiotic treatment is typically ampicillin or penicillin, with alternatives including ceftriaxone, cefotaxime, clindamycin, or vancomycin, depending on the severity of the infection and local susceptibility patterns, as recommended by the Pediatric Infectious Diseases Society and the Infectious Diseases Society of America 1.

Key Considerations

• The choice of antibiotic should be guided by the severity of the infection, with more severe cases requiring hospitalization and intravenous antibiotics.
• Local resistance patterns should be considered when selecting an antibiotic, as Streptococcus pneumoniae is increasingly showing resistance to certain antibiotics.
• The treatment duration typically ranges from 5-14 days, depending on the severity of the infection.

Antibiotic Options

• For Streptococcus pneumoniae with MICs for penicillin <2.0 µg/mL, preferred parenteral therapy includes ampicillin or penicillin, with alternatives including ceftriaxone or cefotaxime 1.
• For Streptococcus pneumoniae resistant to penicillin, with MICs ≥4.0 µg/mL, preferred parenteral therapy includes ceftriaxone, with alternatives including ampicillin, levofloxacin, or linezolid 1.
• Oral therapy options include amoxicillin, second- or third-generation cephalosporins, or oral levofloxacin or linezolid, depending on the severity of the infection and local susceptibility patterns 1.

Special Considerations

• In patients with penicillin allergy, alternatives include respiratory fluoroquinolones or macrolides, such as azithromycin or clarithromycin 1.
• Vancomycin or clindamycin may be used in combination with a beta-lactam antibiotic for severe infections or in areas with high rates of resistance 1.

From the FDA Drug Label

Streptococcus pneumoniae (including multi-drug resistant isolates [MDRSP] ) Community-Acquired Pneumonia Due to Multi-Drug Resistant Streptococcus Pneumoniae Levofloxacin was effective for the treatment of community-acquired pneumonia caused by multi-drug resistant Streptococcus pneumoniae (MDRSP). Of 40 microbiologically evaluable patients with MDRSP isolates, 38 patients (95%) achieved clinical and bacteriologic success at post-therapy.

• Levofloxacin is effective against Streptococcus pneumoniae, including multi-drug resistant isolates.
• Azithromycin is also indicated for the treatment of community-acquired pneumonia due to Streptococcus pneumoniae. The antibiotics that would be used for Streptococcus pneumoniae infection are levofloxacin and azithromycin 2, 2, 3.

From the Research

Antibiotics for Streptococcus pneumoniae Infection

• Levofloxacin is a fluoroquinolone antibacterial agent with a broad spectrum of activity against Gram-positive and Gram-negative bacteria and atypical respiratory pathogens, including Streptococcus pneumoniae 4.
• It is active against both penicillin-susceptible and penicillin-resistant Streptococcus pneumoniae, with a prevalence of S. pneumoniae resistance to levofloxacin of <1% overall in the US 4.
• Amoxicillin and penicillin G are also recommended as treatment for pediatric community-acquired pneumonia (CAP) caused by Streptococcus pneumoniae 5.
• High-dose amoxicillin may still be required to treat pediatric CAP, especially if using CLSI breakpoints 5.
• Ceftriaxone resistance rates have increased over the years, and its use as an empirical antimicrobial against pneumococcal infections should be done with caution 6.
• Penicillin G is still considered a treatment option for pneumococcal pneumonia, with an optimum "high-dose" regimen for life-threatening pneumococcal pneumonia consisting of a 3 million unit loading dose followed by continuous infusion of 10 to 12 million units of freshly prepared drug every 12 hours 7.

Resistance Patterns

• Resistance rates of Streptococcus pneumoniae to penicillin, erythromycin, ceftriaxone, levofloxacin, and vancomycin were 16.2%, 84.7%, 25.9%, 3.3%, and 0.0%, respectively, in a study conducted in South Korea from 2009 to 2018 6.
• Multidrug resistance was twice as common among patients ≤ 4 years old (25.3%) as among patients 5 to 10 years old (13.7%), 11 to 17 years old (11.9%), 18 to 64 years old (12.1%), and > 64 years old (12.4%) 8.
• Levofloxacin resistance was detected in 2 of 2,834 isolates (0.07%) from patients <18 years old in a study conducted in the US from 2000 to 2002 8.