Urinary tract infections (commonly abbreviated as UTIs) refer to bacterial infections that affect different parts of the urinary tract. In the majority of cases, urinary tract infections are ascending bacterial infections. This means that in most cases, bacteria gain entry into the urinary tract through the urethra, and migrate upwards to infect the urinary bladder. Infection of the urinary bladder (technically referred to as cystitis) is a common feature of most urinary tract infections.
Read more about UTI.
In some cases, bacterial infections may ascend beyond the urinary bladder and infect the ureters and the kidneys. Another route through with urinary tract infections may happen is through the bloodstream. In these cases, pathogenic bacteria gain entry into the body through regions other than the urinary tract.
Once the bacteria have entered the body, the bacteria may reach the organs of the urinary tract by travelling through the bloodstream rather than by ascending up the urinary tract. This route of infection is referred to as the hematogenous spread. A third way of getting urinary tract infections is via direct spread of bacteria from a nearby organ in the pelvic region.
However, urinary tract infections through the hematogenous and other routes are very rare. In the majority of cases, urinary tract infections occur via ascendng up the urinary tract.
Signs and Symptoms of UTIs
Urinary tract infections can occur in both males and females. However, females are more prone to getting urinary tract infections than males. This is especially the case in childhood and adolescence. In some cases, urinary tract infections may be silent. This means that urinary tract infections may exist in an individual without causing any obvious signs and symptoms. However, such cases are rare. In most cases, urinary tract infections are accompanied by some typical signs and symptoms.
Read more about urinary problems.
Frequent urge to urinate
One of the most common symptoms of urinary tract infections is a frequent urge for passing urine. This repeated urge to pass urine occurs even when the urinary bladder is not full. Every time an affected person urinates after having the urge, only a small volume of urine is passed out. Despite this, there is frequently the feeling of not being able to empty the urinary bladder completely.
The urge to pass urine may even occur constantly. Having an urge to pass urine more than eight times a day should be taken as a symptom of a possible urinary tract infection. However, one must keep in mind that individuals vary in their urination frequency.
Burning sensation during and after urination
A burning sensation that is present during or after urination is also a characteristic symptom of urinary tract infections. The burning sensation is most intense during the act of urination, but is also present after urination is complete.
Apart from the genitals, the burning sensation may also be felt in the lower abdominal region that is just below the umbilicus (commonly known as belly button), and in the region behind the genitals. In most cases, the intensity of the burning sensation is highest at the tip of the genitals. However, this does not mean that the infection is restricted to the tip of the genitals.
Discolored and cloudy urine
The color of normal urine ranges from clear and transparent to various shades of yellow. The intensity of yellow color depends on how concentrated the urine is. Less water intake tends to result in urine with darker shades of yellow. However, a strong yellow color of urine does not indicate any pathology. In urinary tract infections, the urine turns from clear and transparent to cloudy.
The color of the urine also changes, and varies from pink or red to dirty brown. These changes in the clarity and color of urine are caused by the presence of blood and pus in the urine. It is important to note that there could also be other reasons for cloudy or discolored urine.
Strong odor in urine
In urinary tract infections, the urine has a strong unpleasant odor. People may describe the odor as a strong ammonia-like smell or a fish-like odor. The odor may linger on after urination, and may also be present on the genitals and the underwears. The strong odor may not, however, be apparent in every single case of urinary tract infection.
In some cases, the offensive odor may become strong enough to be detected by other people who are in close proximity to the person suffering from the urinary tract infection. This is more likely to happen when the affected individual fails to wash or clean the genital area after urination.
Pain in the rectum and pelvis
Individuals suffering from urinary tract infections may sometimes report pain in the pelvic region or the rectum. Pain in the pelvic region is mostly reported by women with urinary tract infections, and is often difficult to isolate to a specific spot. Men are more likely to complain of pain in the rectum. In cases where urinary symptoms are mild or non-existent, pain in the rectum may be interpreted as a problem in the colon rather than in the urinary tract. Pain in the rectum or pelvis may occur days or weeks before the onset of the urinary symptoms.
Pain in the abdominal region
Most urinary tract infections affect the urinary bladder, which is located within the pelvic cavity. For this reason, most urinary tract infections are characterized by pain in the pelvic area. In some cases, pain may also be felt in the lower abdominal region (below the umbilicus) and the abdominal flanks. Pain in the abdominal flanks can be caused by infection of the ureters and/or the kidneys.
Fever, nausea and vomiting
Fever is not a common occurrence in urinary tract infections, especially when the infections are restricted to the urethra, urinary bladder or the ureters. However, fever may occur when the urinary tract infection spreads to the kidneys. When the kidneys get infected, nausea and vomiting may also occur.
Since nausea, vomiting and fever are more common in gastrointestinal infections, one may not readily suspect the presence of a urinary tract infection when these signs and symptoms occur. Kidney infection is usually suspected when nausea, vomiting, and fever are also accompanied by urinary symptoms and pain in the abdominal flanks.
The early stages of a urinary tract infection may not present with any specific signs and symptoms related to the urinary tract. However, a general feeling of being unwell (also known as malaise) may occur. Affected individuals may describe this feeling of malaise as being “flu-ish”. A loss of appetite may also accompany the general feeling of malaise.