Urinary tract infections (UTI) are infections that are due to the colonization of pathogenic organisms (mainly bacteria) in the urinary tract. UTIs should not be mistaken for sexually transmitted infections (STIs); they are different entities. UTIs can be classified based on the part of the urinary tract involved:
1. Lower UTI (eg. urethritis, prostatitis, and cystitis involves the urethra, prostate, and bladder respectively)
2. Upper UTI (Pyelonephritis involves the ureters up to the kidneys)
UTIs are commoner in women than men because of the influence of hormonal changes as well as anatomically shorter urethra (a tubular structure that connects the external genitalia to the bladder) in women. UTI in men is rare and, when it occurs, it is usually more complicated. UTI also occurs in children and it is commoner in boys.
Other risk factors for UTI include:
-Extremes of age (infants and the elderly)
-Other immunocompromised states such as cancer chemotherapy, HIV, Diabetes mellitus, use of antibiotics or steroids etc.
-Instrumentation of the urinary tract.
-Anatomical anomalies of the urinary tract
SIGNS AND SYMPTOMS
UTI can be present without any symptoms. This is called ASYMPTOMATIC BACTERIURIA.
Also, females can have candida incidentally detected in their urine (Candiduria) due to contamination from yeast infection the genital tract. UTI in children presents with non-specific symptoms and they are usually unable to report symptoms specific to the urinary tract.
Signs/symptoms suggestive of UTI include:
-Dysuria: painful urination, often described as a “burning sensation” while passing urine
-Urgency: a sudden, uncontrollable urge to pass urine
-Frequency: unusual increase in frequency of urination per day, often in small quantities
-Hesitancy: difficulty in initiating urination despite the urge (in men)
-Poor stream: Short breaks in the flow of urine (in men)
-Enuresis – bedwetting in children who have been previously toilet-trained. This can happen to some adults too.
-Lower abdominal pain or discomfort
-False sensation of bladder fullness or incomplete voiding
-Flank pain – suggests upper UTI
-Bloody urine – this is a red flag
-General feeling of unwell, fever, chills, rigors, body aches and weakness, nausea and vomiting – common in upper UTI
UTI is easily diagnosed from the signs and symptoms but it is important to carry out some tests to determine the cause and specific treatment. The main tests done are URINE ANALYSIS and CULTURE AND SENSITIVITY. A “clean catch” or “mid-stream” urine sample is collected and analyzed in the lab to check for certain signs of infection in the urine (leukocytes, nitrites, proteinuria, etc).
The commonest offending organism is Escherichia coli. Empirical antibiotics can be started while awaiting results of the tests, however, indiscriminate use of antibiotics should be avoided because this can result in resistance and recurrence.
Other blood tests such as full blood count and renal function test could also be done. In complicated or recurrent cases, imaging studies such as ultrasound and CT scan may be required.
Treatment is based on antibiotic sensitivity. Common antibiotics used include: Septrin, Nitrofurantoin, Amoxicillin/Augmentin, Cephalosporins like cefuroxime.
For resistant organisms such as MRSA, hospital admission and intravenous antibiotics as well as contact precaution may be required.
For pyelonephritis, especially in immunocompromised patients, management is more aggressive with optimal intravenous fluids to prevent acute kidney shutdown, plus other supportive measures.
Surgical intervention may be (but rarely) required.
1. UTIs are quite common in women especially within the reproductive age group.
2. UTI in pregnancy can lead to complications such as miscarriage and preterm delivery.
3. Acute pyelonephritis should be treated promptly and aggressively to prevent severe sepsis and kidney failure.
4. UTI is not so common in men. When it occurs, especially if recurrent, a structural anomaly or background immunosuppression should be investigated and treated as required.
5. Prompt diagnosis and treatment of UTI in children is necessary, to avoid complications. This requires a high index of suspicion by caregivers and early presentation to the hospital.