The Centers for Disease Control and Prevention (CDC) identifies more than 50%
of overall antibiotic prescriptions written for the treatment of uncomplicated urinary tract
infections (UTIs) in the outpatient setting are inappropriate. Contributing to this problem
includes prescribing a broad-spectrum antibiotic when a narrow-spectrum option is
available, incorrect duration of therapy, and prescribing antibiotics when the condition
does not warrant antimicrobial treatment (Heppner et al., 2020). Therefore, it is vital for
healthcare providers to understand how to properly diagnose and treat this common
condition.
Risk factors for UTI include female gender, pregnancy, history of UTIs or
recurrent infections, diabetes mellitus or other immunocompromising conditions, failure
to void after intercourse or increased sexual intercourse, spermicide use, infected renal
calculi, low fluid intake, poor hygiene and urinary catheterization (Codina Leik, 2018).
The bacteria, Escherichia coli (E. coli) and Klebsiella pneumoniae (K. pneumoniae), are
the main bacterial strains that lead to in the outpatient setting. Other causative
organisms include Pseudomonas aeruginosa, Proteus mirabilis, Staphylococcus aureus
and Enterococcus faecalis (Salh, 2021).
Diagnostic symptoms of urinary tract infections include change in frequency,
dysuria, urgency, and presence or absence of vaginal discharge, but urinary tract
infections may present differently in older women (Salh, 2021). A more acute
presentation, including high fever, chills, flank pain, costovertebral angle (CVA)
tenderness, nausea, and vomiting is suggestive of complicated UTI. Patients should be
queried about their sexual and medical history, specifically immunocompromising
disease or drugs, and any recent procedures they may have had performed (Buttaro et
al., 2021). A thorough review of symptoms and physical exam should be done.
In cases in which the probability of urinary tract infection is moderate or unclear,
urine culture should be performed. Urine culture is the gold standard for detection of
urinary tract infection. However, asymptomatic bacteriuria is common, particularly in
older women, and should not be treated with antibiotics (Chu & Lowder,
2018). Cultures should always be obtained in young men because these infections are
unusual and suggestive of an underlying problem (Buttaro et al., 2021).
Urinary tract infections can be classified as uncomplicated, complicated,
recurrent, or asymptomatic. Uncomplicated UTIs are characterized by a recent onset of
mild to moderate symptoms and occur in healthy female patients who are not
immunocompromised or pregnant, and without a history of frequent UTIs or structural
abnormalities. UTIs are considered complicated in any male patient, or if the infection is
associated with a structural or functional abnormality of the urinary tract, as these can
lead to serious consequences if treated improperly. Recurrent UTIs , commonly found in
young females, are symptomatic UTIs that occur after treatment and resolution of
symptoms (Buttaro et al., 2021).
Asymptomatic bacteriuria is the presence of bacteria in the properly collected
urine of a patient that has no signs or symptoms of a urinary tract infection. It is very
common in clinical practice and its incidence increases with age. Most patients with
asymptomatic bacteriuria will never develop symptomatic UTIs and will have no adverse
consequences. The patients that should be treated for asymptomatic bacteriuria include
pregnant patients, patients undergoing urologic procedures in which mucosal bleeding
is expected, and patients who are in the first three months following renal
transplantation (Givler & Givler, 2021).
When reviewing UA results the provider should be looking at the color, clarity and
if there is any hematuria. Positive nitrites, leucocytes (white blood cells), and alkaline
urine may be present in patients with UTI (Yates, 2016). The most important thing for
providers to consider is that UA results should be interpreted in conjunction with an
individual’s clinical presentation.
The presence of nitrites can be suggestive of a UTI but clinical presentation of
symptoms should also be taken into account. The absence of nitrites, however, does
not always rule out the presence of a UTI; Nitrites are not usually found in urine and are
associated with the presence of bacteria that can convert nitrate into nitrite (Yates,
2016).
Leukocytes are usually associated with a urinary infection but sometimes may
indicate a more severe renal problem. Alkaline urine may indicate a UTI with certain
types of bacteria, such as Proteus mirabilis, Klebsiella or Pseudomonas. However, pH
is also affected by other factors such as diet. Blood in the urine can be indicative of
kidney disease; inflammatory lesions of the urinary tract (infection or cancer); renal
damage; or kidney/renal stones. It can also indicate a blood-clotting disorder or be a
side-effect of anticoagulant drugs (Yates, 2016). Hematuria could also be a normal
finding in a patient menstruating.
When reviewing the urinalaysis, a large number of epithelial cells indicates
sample contamination. A leukocyte level of > 10 WBCs/ml could indicate UTI. For
culture and sensitivity, greater than or equal to 105 colony forming units (CFU)/ml of
bacteria of one dominant kind is indicative of UTI. Nitrites could mean the patient has an
infection with gram negative bacteria, usually E. Coli. Hyaline casts are normal and may
be seen in concentrated urine, however WBC casts may be seen with infections and
RBC casts and proteinuria are diagnostic of glomerulonephritis (Codina Leik, 2018).
Studies have shown that provider education and use of evidence-based treatment
algorithms are effective to improve prescribing concordance with clinical guidelines and
antimicrobial stewardship (Heppner et al., 2020). Antiobiotic choice is empiric, covering
enteric organisms. First-line options include nitrofurantoin and trimethoprimsulfamethoxazole (TMP-SMX). Other options include
References
Buttaro, T. M., Polgar-Bailey, P., Sandberg-Cook, J., & Trybulski, J. (2021). Primary
care: Interprofessional collaborative practice (6th ed.). Elsevier.
Chu, C. M., & Lowder, J. L. (2018). Diagnosis and treatment of urinary tract
infections across age groups. American Journal of Obstetrics and Gynecology,
219(1), 40–51. https://doi.org/10.1016/j.ajog.2017.12.231
Codina Leik, M. T. (2018). Adult-gerontology nurse practitioner certification intensive
review: Fast facts and practice questions (pp. 280–281). Springer Publishing
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Givler, D. N., & Givler, A. (2021, October 11). Asymptomatic bacteriuria. StatPearls
[Internet]. Retrieved January 18, 2022, from
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https://doi.org/10.1016/j.nurpra.2020.06.003
Salh, K. K. (2021, June 24). Evolution of the antimicrobial resistance of bacteria causing
urinary tract infections. Physician's Weekly. Retrieved January 18, 2022, from
https://www.physiciansweekly.com/evolution-of-the-antimicrobial-resistance-ofbacteria-causing-urinary-tract-infections?pagetype=general-urology
Yates, A. (2016). Urinalysis: how to interpret results. Nursing Times; Online issue 2, 1-3.