Does cephalexin (Cefalexin) treat Group B Streptococcus (GBS) cellulitis?

From the Guidelines

Cephalexin is not the recommended treatment for Group B Streptococcus (GBS) cellulitis, as the provided evidence does not support its use for this specific condition. The most recent and highest quality study, 1, provides guidelines for the diagnosis and management of skin and soft tissue infections, including cellulitis, but does not specifically address GBS cellulitis. However, it does recommend antibiotics active against streptococci, such as penicillin, amoxicillin, or clindamycin, for the treatment of typical cellulitis.

Key Considerations

• The study 1 focuses on the prevention of perinatal group B streptococcal disease and recommends intrapartum chemoprophylaxis with penicillin or ampicillin for GBS-colonized women, but does not address the treatment of GBS cellulitis.
• The study 1 suggests that a 5-day course of antimicrobial therapy may be as effective as a 10-day course for uncomplicated cellulitis, if clinical improvement has occurred by 5 days.
• Cephalexin is a first-generation cephalosporin that inhibits bacterial cell wall synthesis, but its effectiveness against GBS is not specifically addressed in the provided evidence.

Treatment Recommendations

• For patients with GBS cellulitis, antibiotics active against streptococci, such as penicillin or amoxicillin, may be considered as first-line treatment.
• Alternative antibiotics like clindamycin may be used in patients with penicillin allergies, though cross-reactivity with cephalosporins is possible in those with severe penicillin allergies.
• Patients should complete the full course of antibiotics even if symptoms improve quickly, and should seek medical attention if fever persists, the affected area worsens, or if they develop a rash or other signs of allergic reaction.

From the Research

Cephalexin Treatment for Group B Streptococcus Cellulitis

• The effectiveness of cephalexin in treating Group B Streptococcus (GBS) cellulitis is not directly addressed in the provided studies, but some information can be inferred from the available data 2, 3, 4, 5, 6.
• A study from 1983 found that cephalexin is effective in treating streptococcal and staphylococcal skin infections, with cure rates of 90% or higher 2.
• Another study from 1997 examined the susceptibility of clinical group A, B, C, F, and G beta-hemolytic streptococcal isolates to various antimicrobial drugs, including cephalexin, but did not specifically address the treatment of GBS cellulitis 3.
• A 1998 study assessed the antibiotic susceptibility profile of group B streptococcus acquired vertically and found that all isolates were susceptible to penicillin G, ampicillin, and cefazolin, but the study did not mention cephalexin 4.
• A case report from 1985 described a patient with GBS cellulitis who was treated with penicillin G, but cephalexin was not mentioned as a treatment option 5.
• A 2017 randomized clinical trial compared the effectiveness of cephalexin plus trimethoprim-sulfamethoxazole versus cephalexin alone in treating uncomplicated cellulitis, but the study did not specifically address GBS cellulitis 6.
• Based on the available data, it appears that cephalexin may be effective in treating streptococcal skin infections, but its effectiveness in treating GBS cellulitis specifically is not well established 2, 3, 4, 5, 6.

Susceptibility of Group B Streptococcus to Cephalexin

• The susceptibility of GBS to cephalexin is not directly addressed in the provided studies, but some information can be inferred from the available data 2, 3, 4.
• A study from 1997 found that GBS isolates were susceptible to various antimicrobial drugs, including cefazolin, but the study did not specifically address cephalexin 3.
• Another study from 1998 found that all GBS isolates were susceptible to penicillin G, ampicillin, and cefazolin, but the study did not mention cephalexin 4.
• Based on the available data, it appears that GBS may be susceptible to cephalexin, but further studies are needed to confirm this 2, 3, 4.

Clinical Use of Cephalexin for Group B Streptococcus Cellulitis

• The clinical use of cephalexin for treating GBS cellulitis is not well established, and further studies are needed to determine its effectiveness 2, 3, 4, 5, 6.
• Penicillin G and ampicillin are currently recommended as the first-line treatments for GBS infections, including cellulitis 4, 5.
• Cephalexin may be considered as an alternative treatment option for patients who are allergic to penicillin or ampicillin, but its effectiveness in treating GBS cellulitis is not well established 2, 3, 4.