Urinary system infection (UTI) is the most common micro bacterial infection all around the world and it accounts for 1-3% of consultation (Davidson practical medicine, 21st Edition). Rectal flora may enter the urinary tract and cause UTI in healthy person. Up to half of females have UTI and 3% of women have UTI at the age 20, increasing by about 1% in each following decade. In male urinary, the disease or the infection is infrequent but that does not include the first year of the life and above the age of 60.
UTI causes a great deal of discomfort and inconvenience to the patient and in some cases responsible for the asymptomatic or the appearance of more serious cases, such as sepsis and death. UTI is considered one of the most important causes of the imbalance and it can infect people in both sexes at all ages.
Urinary System Infection are the second most common infections in community practice, and it is estimated that they affect up to 150 million individuals per year. There are limited data on the real impact of UTI in the developing world. However, in the United States, UTI has been found to be responsible for 7 million physician visits and more than 100,000 hospital admissions each year, costing the global economy in excess of one billion US dollars.
UTI – Urinary Tract Infection
Definition of UTI
Ouno et al. (2013), in Kenya demonstrated that UTI defined as a condition caused by pathogenic organism invasion of the urinary system which leads to an inflammation in the urothelium. The proliferation of bacteria in the urinary tract leads to UTIs. A urinary tract infection (UTI) is an inflammation in any part of your urinary system your kidneys, ureters, bladder and urethra. Most infections involve the lower urinary tract the bladder and the urethra.
Jha and Bapat (2005) in Kathmandu. Nepal showed that among five hundred samples of patient’s urine from five hospitals collected from January 2005 to April 2005, 244 samples were found to be positive. The most common bacterial isolate was E. coli (49%), followed by Staphylococcus aureas (23%), Proteus sp. (3.6%), Klebsiella sp. (9.71%), Pseudomonas aeruginosa (0.8%) and Citrobacter sp. (2.8%). The study showed that UTI was more common in females of younger age groups as compared to males.
There is a wide spectrum of effects in the UTI ranging from patients who are completely asymptomatic to those with symptoms referable to the urethra, bladder, and those who have acute pyelonephritis with acute flank pain, tenderness and high Temperature as well as with the signs and symptoms of urethritis and cystitis..
Clinical manifestations of UTIs are variable, about 50% of infection did not produce recognizable illness and are discovered incidentally during a general medical examination. The symptoms of UTIs in infants including fever and vomiting. The manifestation in old children and adult, when the symptoms present often suggest the diagnosis.
UTI is the most common infectious diseases in countries that are in the beginning of developing by clinicians with a seamed annual global incidence of at least 250 million. UTI affects all age groups, but females are more susceptible than males, because female have a short urethra, and they do not have the capability of prostatic secretion.
Hamdan et al. in (2011) mentioned that UTI is not only a common infection, but also its range of clinical effect varies from asymptomatic bacteriuria (ASB) to cystitis and pyelonephritis. Females with ASB are most likely to deliver low weight birth or pre-mature infants during pregnancy.
UTIs are most common in elderly males that have an enlargement of the prostate gland and the infection usually follows instrumentation of catheter drainage.
Sources and Routes of Infection
Davis and Flood defined (2011) that, in most patients, pathogen microorganisms go into the urinary tract through the urethra into the bladder; this is known as the ascending way and pathogens initially adhere and grow, they subsequently colonize in urothelium of the distal urethra.
Sexual intercourse is also an important reason in the ascent of bacteria to the bladder. This was proved by study carried out by Okonko et al. (2010), which showed that incidence of UTIs in sexually active women was more common compared to other group of women, because sexual intercourse caused bacteria to be pushed into the urethra.
Hematogenous spread accounts for fewer than 5 percent of documented UTI.Infections, especially of Staphylococcus aureus, Salmonella sp. and Mycobacterium tuberculosis, can occasionally reach the kidney through the blood.
Classification of UTIs
Dulczak and Kirk (2005), described that the upper tract infections are located in ureters collecting system and parenchyma such as pyelonephritis. They also defined pyelonephritis as diffuse pyogenic infection of parenchyma of kidney with signs and symptoms including fever over 38.5°C, chills along with flank pain, tenderness with Pouria and positive urine culture.
National Collaborating Centre for female’s and young Children’s Health, London: RCOG Press; 2007. We can classify symptomatizes of UTI to:
- Lower UTI or cystitis
- Upper UTI or acute pyelonephritis (APN)
Mazzulli (2012), in Canada defined that the not-complicated Urinary Tract Infection occurs in healthy patients with a structurally and functionally normal urinary tracts. He also mentioned the uncomplicated UTIs include infections in the lower part of the urinary tract or system (cystitis) and the upper part of the urinary tract or system (pyelonephritis).
Study carried out by Neal (2008), in U.S.A. demonstrated that complicated Urinary Tract Infection occurs in patients with underlying anatomical or functional abnormal urinary tract due to intrinsic or extrinsic factors and usually needed a prolonged course of antibiotics.
Isolated infection is a term used to describe UTIs as a first infection which isolated from patients, which can be treated once, and does not appear in less than six months. Isolated infections can affect about 25-40% of young women.
Sometimes Urinary Tract Infection is caused by unresolved infection because of inadequate antimicrobial therapy, either because of resistance of bacteria to antibiotics that cannot kill it or it is because the patient does not take the medication in the correct way.
Reinfection is characterized by the same or different microorganisms grow during any period of time. Reinfection occurred where it appeared that has been no growth after the infection has been treated. Ninety-five percent of UTIs are due to reinfections.
Relapse UTIs occurs in 5% to 10% of women with a persistence microorganism of the same species causes an Urinary Tract Infection within two weeks of completing antimicrobial therapy.
The Factors Predisposing to UTIs
There are many factors that are causing UTIs. Some of them are given below:
Administration of VUR is argumentative and includes long-term antibiotic protection of Urinary Tract Infection, surgical ways for the VUR, or surveillance only. VUR Partially has a role in the development and progression of pyelonephritis. Childhood VUR is five times more common in girls than boys and it has a genetic background.
The incidence of Urinary Tract Infection in men in their fifth decade and older is very common due to enlargement of the prostate gland. This can cause obstruction to the flow of urine with deficient voiding resulting in remaining urine in the bladder. Prostatic hypertrophy recognized as a risk factor for Urinary Tract Infection.
Hoepelman et al. (2003), in Netherland found that both gender with diabetes mellitus associated with increased risk of acute pyelonephritis or acute cystitis. Also they can see that the adherence of Escherichia coli to uroepithelial cells of females with diabetes mellitus is increased compared with females without diabetes mellitus, and as we can see that the glycosuria promoted the growth of various strain of Escherichia coli. Some data are available related to the role of diabetes mellitus as a risky factor that effects the development of antimicrobial resistance of the pathogens.
The relation between urinary stones and Urinary Tract Infection is frequent. Kidney stones can act as a place in which microorganisms can escape antibiotics and cause recurrent Urinary Tract Infection. Infection by urease enzymes producing organisms such as Proteus mirabilis can stimulate the failure of urea into ammonia and carbon dioxide.
The ammonia produced from this kind of interaction raise the pH of the urine and cause formation of kidney stones.
Anyone can get a urinary tract infection, but it is most common in women, especially if they are pregnant. Partly due to the pressure of the pregnant uterus from the infant that affects the ureters, increases the bladder volume and decreases the bladder tones, elevating the risk of urinary stasis. This effect may also be due to the humoral and immunological changes that happen normally during pregnancy.
Age and gender
Prakash and Saxena (2013), in India showed that from a total of 288 urine samples collected from patients of the age ranging from 15 to ≥ 48 years, 140 were females while 148 were males. Prevalence of Urinary Tract Infection was 53.83% in patients, and the Urinary Tract Infection prevalence was conspicuously higher in females 73.57% than males 35.14%. They also found that the highest prevalence of UTI in males was ≥48 years (71.15%), while in females the highest susceptible age group of 26-36 years (90.69%).
The research has demonstrated that women with certain antigens in the blood (called lewis group) are most susceptible to cystitis. The cells lining the urinary tract appeared to be more receptors to which bacteria can adhere. It has been shown that non-secreting blood group antigens are at risk of Recurrent Urinary Tract Infection. Other glycosaminoglycan layer may be insufficiency, these layers have the proteins that will snare the bacteria and evacuate it, occur on the bladders surface.
If the layer is not intact or sometimes the proteins are not viscous enough, the bacteria will be able to sit in the bladder and proliferate. Mutations in the genes of the integrated host immune responses (interferon receptor, etc.) may also affect the susceptibility to Urinary Tract Infection.