What is the most appropriate antibiotic (abx) for a 77-year-old male with a urinary tract infection (UTI) who was initially prescribed Macrobid (nitrofurantoin)?

From the Guidelines

For a 77-year-old male with a UTI, trimethoprim-sulfamethoxazole (TMP-SMZ) for 14 days or a fluoroquinolone for 7 days would be a better option than macrobid (nitrofurantoin). According to the American College of Physicians, best practice advice for uncomplicated pyelonephritis in men recommends short-course therapy with either fluoroquinolones (5 to 7 days) or TMP-SMZ (14 days) based on antibiotic susceptibility 1. Macrobid is generally less effective against typical male UTI pathogens and has reduced efficacy in patients with decreased renal function, which is common in elderly patients. Additionally, nitrofurantoin doesn't achieve adequate tissue penetration for prostate involvement, which is often present in male UTIs. Some key points to consider when choosing an antibiotic for this patient include:

• The patient's renal function, as nitrofurantoin should be avoided in patients with severely reduced kidney function (creatinine clearance <30 mL/min)
• Local resistance patterns and urine culture results to guide antibiotic selection
• The patient's medication allergies and potential side effects of the chosen antibiotic
• The need for extended treatment duration (7-14 days) to ensure complete eradication of the infection in male UTIs. Given the potential for decreased renal function and prostate involvement in this elderly male patient, TMP-SMZ for 14 days or a fluoroquinolone for 7 days would be a more appropriate choice than macrobid, as recommended by the American College of Physicians 1.

From the FDA Drug Label

nitrofurantoin (macrocrystals) To reduce the development of drug-resistant bacteria and maintain the effectiveness of sulfamethoxazole and trimethoprim tablets and other antibacterial drugs, sulfamethoxazole and trimethoprim tablets should be used only to treat or prevent infections that are proven or strongly suspected to be caused by susceptible bacteria 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

The patient was put on Macrobid, which is a form of nitrofurantoin. Nitrofurantoin is commonly used to treat urinary tract infections.

• The choice of nitrofurantoin for this patient's UTI is reasonable, given its indication for treating urinary tract infections 2.
• However, without culture and susceptibility information, it's difficult to determine if nitrofurantoin is the best choice for this specific patient's infection 3.
• Trimethoprim-sulfamethoxazole is also an option for treating UTIs, but the decision to use one antibiotic over the other should be based on factors such as local epidemiology, susceptibility patterns, and patient-specific factors 3.

From the Research

Treatment Options for UTI in Elderly Patients

The patient in question is a 77-year-old male who has been put on Macrobid for a UTI. Considering the age of the patient, it's essential to choose an antibiotic that is effective and has a favorable resistance profile.

• According to 4, nitrofurantoin is a recommended first-line empiric antibiotic therapy for acute uncomplicated bacterial cystitis.
• A study published in 5 found that nitrofurantoin had a comparatively lower resistance rate, making it a suitable option for outpatient treatment of UTI.
• However, it's crucial to note that the choice of antibiotic should be guided by uropathogen identified by culture and sensitivity, as well as local antibiotic resistance rates 6.
• Additionally, the patient's age and potential comorbidities should be taken into account when selecting an antibiotic, as certain antibiotics may have adverse effects on cognitive function 6.

Considerations for Antibiotic Choice

When choosing an antibiotic for an elderly patient with a UTI, several factors should be considered:

• Local antibiotic resistance rates 4, 5
• Uropathogen identified by culture and sensitivity 6
• Potential adverse effects on cognitive function 6
• Comorbidities, such as diabetes mellitus 6
• History of UTIs 7

Alternative Treatment Options

Non-antimicrobial options, such as cranberry products, OM-89 Escherichia coli bacterial lysate vaccine, and estrogen therapy in postmenopausal women, may be considered for preventing UTIs in elderly patients 7. However, the evidence for their efficacy is weak. A medical device containing xyloglucan, gelatin, propolis, and extracts of Hibiscus sabdariffa has shown promise in controlling and preventing UTIs 7.