What are the first-line antibiotics for urinary tract infections (UTI) in inpatients in Malaysia?

First-Line Antibiotics for Inpatient UTI in Malaysia

For hospitalized patients with UTI in Malaysia, initiate empiric intravenous therapy with either a fluoroquinolone (ciprofloxacin 400 mg IV twice daily or levofloxacin 750 mg IV daily), an extended-spectrum cephalosporin (ceftriaxone 1-2 g IV daily or cefepime 1-2 g IV twice daily), or an aminoglycoside with or without ampicillin (gentamicin 5 mg/kg IV daily or amikacin 15 mg/kg IV daily). 1

Initial Assessment and Classification

Before selecting antibiotics, determine whether the UTI is uncomplicated pyelonephritis or complicated:

• Obtain urine culture and antimicrobial susceptibility testing in all hospitalized UTI cases before starting therapy to guide definitive treatment 1, 2
• Perform urinalysis including white blood cells, red blood cells, and nitrite assessment 1
• Use ultrasound to rule out urinary tract obstruction or renal stones, especially in patients with history of urolithiasis or renal dysfunction 1
• All male UTIs are considered complicated regardless of other factors, requiring 7-14 days of treatment 2

Empiric Parenteral Therapy Options

First-Line Regimens for Uncomplicated Pyelonephritis

• Fluoroquinolones: Ciprofloxacin 400 mg IV twice daily OR levofloxacin 750 mg IV daily 1
• Extended-spectrum cephalosporins: Ceftriaxone 1-2 g IV daily OR cefepime 1-2 g IV twice daily 1
• Aminoglycosides: Gentamicin 5 mg/kg IV daily OR amikacin 15 mg/kg IV daily (with or without ampicillin) 1
• Beta-lactam/beta-lactamase inhibitor: Piperacillin/tazobactam 2.5-4.5 g IV three times daily 1

Alternative Regimens for Complicated UTI

• First-generation cephalosporin: Cefazolin 1 g IV every 8 hours for 5-7 days 3
• Second-generation cephalosporin plus aminoglycoside as an alternative option 2

Critical Considerations for Malaysia

Fluoroquinolone Use Restrictions

• Only use fluoroquinolones if local resistance rates are <10% 1, 2
• Do not use fluoroquinolones empirically if the patient has taken them within the last 6 months 2
• Given increasing resistance rates globally, fluoroquinolones should be restricted for empiric UTI treatment 4, 5

Multidrug-Resistant Organisms

• Reserve carbapenems and novel broad-spectrum agents (ceftolozane/tazobactam, ceftazidime/avibactam, meropenem-vaborbactam) only for patients with early culture results indicating multidrug-resistant organisms 1
• For carbapenem-resistant Enterobacterales, consider ceftazidime-avibactam 2.5 g IV every 8 hours or meropenem-vaborbactam 4 g IV every 8 hours 3
• For difficult-to-treat Pseudomonas, use ceftolozane/tazobactam 1.5-3 g IV every 8 hours 3

Treatment Duration and Monitoring

• Standard duration is 5-7 days for complicated UTIs, with longer courses (up to 14 days) reserved for bacteremia or severe infections 3
• For male patients, treat for 7-14 days as these infections are more difficult to eradicate 2
• Switch to oral therapy once the patient is clinically stable and able to tolerate oral medications 1
• Ensure adequate source control (relief of obstruction, removal of foreign bodies) for optimal outcomes 3

Transition to Oral Therapy

Once clinically improved and afebrile for 24-48 hours, transition to oral antibiotics based on culture results:

• Ciprofloxacin 500-750 mg twice daily for 7 days 1
• Levofloxacin 750 mg daily for 5 days 1
• Trimethoprim/sulfamethoxazole 160/800 mg twice daily for 14 days (if susceptible and local resistance <20%) 1, 6

Common Pitfalls to Avoid

• Do not treat for less than 7 days in males or complicated UTIs, as this leads to treatment failure 2
• Do not use aminoglycoside monotherapy for systemic infections—reserve it only for urinary tract infections 3
• Failing to obtain urine culture before starting therapy may lead to inappropriate antibiotic selection 2
• Using fluoroquinolones empirically when local resistance exceeds 10% increases treatment failure risk 2
• Not managing underlying urological abnormalities results in recurrent infections 2
• Consider imaging (CT scan) if patient remains febrile after 72 hours or if clinical status deteriorates 1

Renal Dose Adjustments

• For cefazolin: CrCl 10-30 mL/min use 1 g IV every 12 hours; CrCl <10 mL/min use 1 g IV every 24 hours 3
• Adjust aminoglycoside dosing based on renal function and therapeutic drug monitoring 1