From the Guidelines
Australian guidelines for urinary tract infections (UTIs) in adults recommend short-course antibiotics, such as nitrofurantoin for 5 days, trimethoprim-sulfamethoxazole (TMP-SMZ) for 3 days, or fosfomycin as a single dose for uncomplicated cystitis in women. When considering the treatment of UTIs, it is essential to differentiate between uncomplicated and complicated infections, as well as the specific type of infection, such as cystitis or pyelonephritis.
- For women with uncomplicated bacterial cystitis, the recommended treatment options include:
- Nitrofurantoin for 5 days
- Trimethoprim-sulfamethoxazole (TMP-SMZ) for 3 days
- Fosfomycin as a single dose 1
- For men and women with uncomplicated pyelonephritis, the recommended treatment options include:
- Fluoroquinolones for 5 to 7 days
- TMP-SMZ for 14 days, based on antibiotic susceptibility 1 The rationale behind these recommendations is to target the most common uropathogens, such as Escherichia coli, while minimizing antibiotic resistance and adverse effects 1. It is also important to note that asymptomatic bacteriuria should not be treated, except in pregnancy, and that urine culture is recommended before starting antibiotics for complicated UTIs, recurrent infections, or treatment failure. Adequate fluid intake and urinary analgesics like phenazopyridine may provide symptomatic relief during treatment. In terms of specific treatment regimens, the guidelines suggest that fluoroquinolones are highly efficacious in 3-day regimens but have a high propensity for adverse effects and should therefore be reserved for patients with a history of resistant organisms 1.
From the FDA Drug Label
The usual adult dosage in the treatment of urinary tract infections is 4 teaspoonfuls (20 mL) of sulfamethoxazole and trimethoprim oral suspension every 12 hours for 10 to 14 days. The FDA drug label does not provide information on Australian guidelines for UTI in adults. The provided text only discusses the dosage and administration of trimethoprim/sulfamethoxazole for urinary tract infections in adults, but does not mention any specific guidelines for Australia 2.
From the Research
Australian Guidelines for UTI in Adults
- The recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis in otherwise healthy adult nonpregnant females is a 5-day course of nitrofurantoin, a 3-g single dose of fosfomycin tromethamine, or a 5-day course of pivmecillinam 3.
- High rates of resistance for trimethoprim-sulfamethoxazole and ciprofloxacin preclude their use as empiric treatment of UTIs in several communities, particularly if patients who were recently exposed to them or in patients who are at risk of infections with extended-spectrum β-lactamases (ESBLs)-producing Enterobacteriales 3.
- Second-line options include oral cephalosporins such as cephalexin or cefixime, fluoroquinolones and β-lactams, such as amoxicillin-clavulanate 3.
Diagnosis and Management
- An acute uncomplicated urinary tract infection (UTI) is a bacterial infection of the lower urinary tract with no sign of systemic illness or pyelonephritis in a noncatheterized, nonpregnant adult with no urologic abnormalities or immunocompromise 4.
- Urine culture and susceptibility testing should be reserved for women with recurrent infection, treatment failure, history of resistant isolates, or atypical presentation to make a definitive diagnosis and guide antibiotic selection 4.
- First-line antibiotics include nitrofurantoin for five days, fosfomycin in a single dose, trimethoprim for three days, or trimethoprim/sulfamethoxazole for three days 4.
Prevention of Recurrent Infections
- Increased fluids, intake of cranberry products, and methenamine hippurate can prevent recurrent infections 4.
- Antibiotic prophylaxis is also effective in preventing recurrence but has a risk of adverse effects and antimicrobial resistance 4.
Treatment for Men
- Men with lower UTI symptoms should always receive antibiotics, with urine culture and susceptibility results guiding the antibiotic choice 4.
- First-line antibiotics for men with uncomplicated UTI include trimethoprim, trimethoprim/sulfamethoxazole, and nitrofurantoin for seven days 4.
Treatment for Older Adults
- Uncomplicated UTIs in nonfrail women and men 65 years and older with no relevant comorbidities also necessitate a urine culture with susceptibility testing to adjust the antibiotic choice after initial empiric treatment; first-line antibiotics and treatment durations do not differ from those recommended for younger adults 4.