Inappropriate Use of Nitrofurantoin in the Elderly

Madden, T

Sentara Martha Jefferson Hospital

When selecting antibiotics for the treatment of urinary treat infections (UTIs) in elderly patients there

are unique considerations a clinician must consider in the choice of drug therapy, including both the age

and the current renal function of the presenting patient. A common drug that is prescribed for various

patient populations for treatment of UTIs is nitrofurantoin. Due to rising resistance of different

pathogens to other first-line antibiotics, nitrofurantoin has found a niche as an alternative therapy for

prescribers in treating this infection due to its pharmacokinetic properties of limited systemic

distribution and high concentrations accumulating in the urinary tract. Concentration of the drug in

urine is dependent on adequate renal function of the patient. However, a known aspect of aging is the

gradual decline in renal function. Since this physiological change is occurring in the elderly population,

treatment failure for UTIs with nitrofurantoin is of real concern.

The objective of this project was to evaluate the incidence and outcomes of patients who presented to

the emergency department with either an initial diagnosis of UTI or a diagnosis deemed to be related to

a UTI, who were previously prescribed nitrofurantoin in the outpatient setting and determine whether

age-related renal dysfunction correlates with treatment failure. The data collected will be used to help

inform local outpatient prescribers about the treatment failure risks of using nitrofurantoin in the

studied patient population.

This study was retrospective, evaluating patients from April 1, 2015 to September 30, 2015 via chart

review. Patients included in the analysis were female patients >65 years of age treated or given

prophylaxis therapy with nitrofurantoin in the outpatient setting, who then subsequently presented to

the emergency department with a UTI related initial diagnosis. Other data collected included patient

specific parameters to calculate creatinine clearance (i.e. weight, serum creatinine, etc.), presenting

diagnosis, patient admissions, length of stay for any admissions, development of sepsis believed to be of

urinary origin, and death.

In the preliminary analysis 1548 patient charts have been reviewed. On initial review of the charts,

inclusion criteria were promptly evaluated for female sex and appropriate age. Once a patient met

those screening criteria, the chart was reviewed in depth for current use of nitrofurantoin before

presentation to the emergency department. Ultimately, eleven patients were identified who presented

to the emergency department for treatment failure on nitrofurantoin who met inclusion criteria where

the presenting issue was possibly related to having a UTI.

From a preliminary stand-point, the results have shown that only 0.7% of patients reviewed presented

to the emergency department with a UTI or UTI associated issue that was related to treatment failure on

nitrofurantoin. To date, it is clear that some education needs to be given to providers on the misuse of

nitrofurantoin in order to prevent even a small amount of patients from being inappropriately

prescribed this antibiotic.