Urinary tract includes kidney, ureter (tube joining kidney and bladder), urinary bladder (stores the urine) and urethra (tube through which urine exits the body). Urinary tract infection is an infection in any part of the urinary tract. Urinary infection is relatively more common in women due to structure of urethra which is short and close to anus and vagina. The risk of urinary infection increases with age and above 60 years both males and females have equal risk of getting infection. Urinary infection can be purely asymptomatic i.e. without any symptom or can cause serious consequences if it spreads to kidney. Urinary infection is divided into uncomplicated UTI and complicated UTI. Uncomplicated UTI involves urethra and urinary bladder whereas complicated UTI affects kidneys. Recurrent UTI, urinary infection with involvement of prostate in males and infection in structurally abnormal urinary tract is also categorized as complicated UTI.
The symptoms of UTI could be frequent urge to urinate, burning sensation or pain during urination, small quantity of urine, urine may appear cloudy, red or pink urine is a sign of blood in the urine, strong smelling urine, pelvic pain in females or pain in lower abdomen. If kidney is affected the patients may experience upper back and side pain, high fever, shaking and chills, nausea and vomiting. The most common (and often only) symptom in young children is fever. Similarly, in the elderly, the symptoms can be vague and non-specific, such as fatigue, confusion and incontinence.
Normal urine has no bacteria in it, and one way flow help prevent infection. Urinary infection occurs when bacteria enters into urinary tract through the urethra and start multiplying in bladder. Bacteria may gain access to urethra from anus or vagina. Bacteria that enters into urethra causes urethritis with symptoms of burning urination and pus or mucus discharge from urethra. Once bacteria enters urinary bladder, it causes cystitis characterized by pelvic pain, lower abdominal discomfort, painful urination and blood in the urine. Involvement of kidneys may results in serious complications or systemic infection (sepsis).
Risk factors for urinary infections are female urinary tract, sexual activity, usage of barrier contraceptives or spermicidal cream, pregnancy and menopause. Other risk factors are abnormal urinary tract, blockage in urinary tract with kidney stones or enlarged prostate, uses of catheter, any recent urinary procedures or instrumentation and suppressed immune system like diabetes, cancer and long term steroid therapy. Neurological condition like spinal cord injury, multiple sclerosis and others may increase the risk of urinary infections due to incontinence and presence of catheter.
Urinary tract infection is diagnosed by urine examination that may contain, white cells, red cells, or pus cells. Mid-stream urine sample is taken to isolate infective organism (bacteria) and also to confirm its sensitivity to antibiotics. In cases of recurrent urinary infections if there is a suspicion of structural defect in urinary tract, ultrasonography, CT scan or MRI can be suggested by the doctor to visualize for any abnormality. In some cases doctor may ask to go for a cystoscopy examination. A long thin tube with a lens (cystoscope) is inserted in the urethra and passed through to the bladder to directly see urethra and bladder.
Usual treatment of UTI is administration of antibiotics to kill the bacteria. The nature of antibiotic and duration of treatment depends on the type of bacteria found in the urine. Usually patients with uncomplicated UTI are prescribed antibiotics without going for urine culture. The drug is given for a shorter course of 1 to 3 days. In case of poor response to short course, recurrent infections, or complicated UTIs, long course of antibiotics is given that may last from few days to weeks. The prescribed course of antibiotics should be taken to prevent any further relapse or complications. It is important to know that elderly patients with UTI are more prone to develop complications than younger age groups. In a recent study it is emphasized that elderly patients with urinary infection should be started on antibiotics as early as possible to reduce the risk of further complication. Further hospital acquired urinary infection may be resistant (unresponsive) to conventional antibiotics and require newer generation injectable antibiotics. Patients with complicated UTI are also treated with injectable antibiotics followed by oral drugs.
Doctor may also prescribe a pain medicine (analgesic) for pain relief experienced during urination. Pain is mostly relieved by starting treatment with antibiotic. High fluid intake mainly alkaline substances would reduce the symptoms of burning sensation felt during urination.
Patient with urinary infection associated with sexual activity may be prescribed single dose of antibiotic to be taken after sexual intercourse. Menopausal women with recurrent urinary infections may benefit from vaginal estrogen ( female hormone) therapy.
Usually there is no risk of major complications if urinary infection is treated early and properly. However, it may cause serious complications if left untreated or treated inappropriately. Complications of urinary infection may include:
- Recurrent urinary infection especially in women who experience four or more UTIs in a year.
- Kidney damage due to infection affecting kidneys (pyelonephritis).
- Urethral stricture in males due to recurrent infection
- Urinary infection in pregnant female may cause low birth weight or premature infant.
- Sepsis: A life threatening complication involving kidney and other organs of the body.
Risk of urinary infection can be reduced by the following methods:
- Drink plenty of water to dilute the urine and allow frequent urination. This will flush out bacteria before any infection settles.
- Proper hygiene in and around urethra, anus and vagina to prevent movement of bacteria to urethra.
- Cleaning under foreskin daily if uncircumcised.
- Empty bladder soon after sexual intercourse. Drink full glass of water to help flush the bacteria.
- Avoid potentially irritating products like deodorant sprays, powder or douches in the genital areas.
- Change contraceptive methods from diaphragm, and spermicidal condoms to others.
- Loose cotton underwear to reduce excess moisture.
Besides taking specific medicines and adopting preventive strategies, people can also try few remedies to increase the effectiveness of the treatment. A supplement of D-mannose can be taken in non-pregnant females. Cranberry juice or tablets can be used to prevent recurrent infection though the scientific evidence is lacking. Probiotic containing lactobacillus may help reduce infection.