Is Morganella typically sensitive to Flagyl (Metronidazole)?

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From the Research

No, Morganella morganii is typically not sensitive to Flagyl (metronidazole). Metronidazole is primarily effective against anaerobic bacteria and certain parasites, while Morganella is a gram-negative, facultative anaerobic bacterium that belongs to the Enterobacteriaceae family.

Key Points to Consider

  • Morganella infections are usually treated with antibiotics that are effective against gram-negative bacteria, such as third-generation cephalosporins, fluoroquinolones, aminoglycosides, or carbapenems, depending on susceptibility testing 1.
  • It's essential to note that Morganella species frequently develop resistance to multiple antibiotics, including ampicillin and first-generation cephalosporins due to chromosomally encoded beta-lactamases 2.
  • When treating a Morganella infection, antibiotic susceptibility testing should be performed to guide appropriate therapy, as resistance patterns can vary between isolates and geographic regions 3.
  • A recent study found that Morganella morganii is often resistant to multiple antibiotics, including ciprofloxacin, trimethoprim/sulfamethoxazole, gentamicin, amoxicillin, nitrofurantoin, and colistin 4.
  • The most common treatment for M. morganii bacteremia was carbapenems, followed by aminoglycosides, ciprofloxacin, and colistin 4.

Recommendations

  • Antibiotic susceptibility testing should be performed to guide appropriate therapy for Morganella infections, as resistance patterns can vary between isolates and geographic regions 1.
  • Treatment of Morganella infections should include antibiotics that are effective against gram-negative bacteria, such as third-generation cephalosporins, fluoroquinolones, aminoglycosides, or carbapenems, depending on susceptibility testing 3.
  • It's crucial to monitor for resistance and adjust treatment accordingly, as Morganella species can develop resistance to multiple antibiotics 2.

References

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This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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