What is the treatment for Morganella morganii (M. morganii) urinary tract infection (UTI)?

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From the Guidelines

Morganella morganii urinary tract infections should be treated with a combination of antibiotics, such as a second-generation cephalosporin plus an aminoglycoside, or an intravenous third-generation cephalosporin, as empirical treatment for complicated UTI with systemic symptoms, as recommended by the European Association of Urology guidelines 1. When treating Morganella morganii urinary tract infections, it is essential to consider the severity of the infection and the patient's underlying health conditions.

  • The choice of antibiotic should be based on susceptibility testing to ensure effective treatment.
  • First-line treatment options may include fluoroquinolones, such as ciprofloxacin, but their use should be limited to cases where the local resistance rate is <10% and the patient does not require hospitalization 1.
  • For more severe infections, intravenous options like third-generation cephalosporins or carbapenems may be necessary.
  • M. morganii is naturally resistant to many antibiotics, including ampicillin, amoxicillin, first-generation cephalosporins, and nitrofurantoin, so these should be avoided.
  • Treatment duration should be 7-14 days, depending on the infection severity, and patients should complete the full course of antibiotics even if symptoms improve quickly 1.
  • Addressing any underlying conditions, such as structural urinary tract abnormalities, is also crucial for preventing recurrence.
  • It is also important to note that short-duration courses of antibiotics (5-7 days) may be effective for complicated UTI, including pyelonephritis, but more data are needed to confirm this, especially in men 1.

From the FDA Drug Label

URINARY TRACT INFECTIONS (complicated and uncomplicated) Caused by Escherichia coli, Proteus mirabilis, Proteus vulgaris, Morganella morganii or Klebsiella pneumoniae Urinary Tract Infections For the treatment of urinary tract infections due to susceptible strains of the following organisms: Escherichia coli, Klebsiella species, Enterobacter species, Morganella morganii, Proteus mirabilis and Proteus vulgaris

  • Treatment options for Morganella morganii in urine include:
    • Ceftriaxone (IV) 2
    • Trimethoprim-sulfamethoxazole (PO) 3
  • Key points:
    • Both ceftriaxone and trimethoprim-sulfamethoxazole are indicated for the treatment of urinary tract infections caused by Morganella morganii.
    • The choice of treatment should be based on susceptibility testing and local epidemiology.

From the Research

Morganella morganii Infections

  • Morganella morganii is a Gram-negative, opportunistic pathogen that can cause various infections, including bloodstream infections, particularly in individuals with compromised immune systems 4.
  • It is often resistant to antibiotics, making treatment challenging 4, 5, 6.

Treatment of Morganella morganii Infections

  • The most common treatment for M. morganii bacteremia is carbapenems, followed by aminoglycosides, ciprofloxacin, and colistin 4.
  • Source control measures, such as surgery, line removal, drainage, and tissue removal, are also used in some cases 4, 7.
  • Gentamicin is frequently used in combination with third-generation cephalosporins or other antibiotics to which M. morganii is susceptible 5.

Antibiotic Resistance

  • M. morganii is naturally resistant to a wide range of antibiotics, including certain penicillins, cephalosporins, macrolides, and sulfamethoxazole 8.
  • However, it is naturally sensitive to aminoglycosides, piperacillin, mezlocillin, ticarcillin, third and fourth generation cephalosporins, carbapenems, aztreonam, quinolones, trimethoprim, and chloramphenicol 8.

Urine Treatment

  • There is limited information available on the specific treatment of M. morganii in urine.
  • However, based on the antibiotic resistance patterns and treatment options for other types of M. morganii infections, it is likely that carbapenems, aminoglycosides, or other broad-spectrum antibiotics may be effective in treating M. morganii urinary tract infections 4, 5, 6.

Professional Medical Disclaimer

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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