Pathogenesis of Urinary Tract Infection and Nursing Strategies

This article discusses the pathogenesis of urinary tract infection (UTI) and the role of uropathogens and host interaction. It explores the immune response and the release of pro-inflammatory mediators. The article also provides nursing strategies for preventing and managing UTI, including proper catheter care and infection prevention techniques.

Medical
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Pathogenesis:
Urinary tract infection is associated with infection due to different enterobacterias. Patients
with risk of sepsis are prone to develop bacteraemia following urinary tract infection.
Urosepsis patients are prone to develop urolithiasis, prostatic adenoma, urologic carcinoma,
and other urologic diseases. UTI mainly occurs due to interaction among uropathogen and
host. Uropathogens get attached to the epithelial surface and subsequently it colonises and
distributes through the mucosa which results in the tissue damage. Bacterial adhesins and its
relevant epithelial binding sites are mainly responsible for progression of infection.
Progression of infection results in the pyelonephritis and renal impairment (Stapleton, 2014;
Haak and Wiersinga, 2017).
Infection results in release of pathogens and pathogen products like pathogen associated
molecular pattern (PAMP) and danger-associated molecular patterns (DAMP). These
pathogen or pathogen products get recognized through receptors of the cells like complement
system, endothelium and adipose tissue which are called as pattern recognition receptors
(PRRs). PAMP bind to PPR present on the surface of macrophages, neutrophils, and
endothelial or urothelial cells. PRRs modulate immunological pathways post infection
through release of pro- and anti-inflammatory mediators and biomarkers. The transcription
factor NF-κB is responsible for the release of pro-inflammatory cytokines like IL-6, IL-12,
and TNFα. In the process, further inflammatory mediators like chemokines, prostaglandins,
thromboxans, and leukotrienes get released (Anderberg, Luther, and Frithiof, 2017; Pop-
Began, Păunescu, Grigorean, Pop-Began, and Popescu, 2014). Nitric oxide (NO) are
produced through endothelial cells which reduces the vascular tone. Reduced vascular tone
results in hypotension. It is evident that Kirkman is associated with hypotension because his
recorded blood pressure is 80/42. Sepsis of the urinary tract infection is associated with
Systemic inflammatory response syndrome (SIRS) and tachycardia is the prominent symptom
of SIRS. Sepsis patients are associated with cardiac arrythmias due to excessive inflammation
and secretion of excessive stress hormones. Infection in sepsis patients also lead to
development of fever. In case of Kirkman also body temperature increased to 39°C which
indicate development of fever. There would be increase in the heart rate in patients with
fever. In sepsis patients, there might be growth of bacteria in the bladder and urethra. It could
lead to pain in patients with UTI and irritation during urination. Kirkman also was
experiencing burning sensation during urination and abdominal pain radiating towards right
flank. Color of the urine get changed in patients with UTI due to pus and tinge of blood. In
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patients with sepsis, there are chances of reduced levels of haemoglobin. Haemoglobin levels
get reduced due to reduced red blood cells production due to systemic inflammatory response
and augmented red blood cells destruction as result of haemolysis and bleeding (Detweiler,
Mayers, and Fletcher, 2015).
In case of Kirkman, haemoglobin level reduced to 8.4mmol/L. Normal haemoglobin level in
male should be 8.67 - 10.8 mmol/L. Reduced haemoglobin levels would lead to impairment
in the oxygen consumption and tissue oxygenation. Reduced haemoglobin level also
produces reduced oxygen carrying capacity of the blood and there would be reduced partial
oxygen pressure and oxygen saturation. In case of Kirkman also oxygen saturation (SPO2)
was reduced to 82%. Normal SPO2 should be between 95 – 100 %. Reduced levels of oxygen
levels in the blood lead to increased work on breathing. Lungs starts breathing at the faster
rate to breath in more oxygen to compensate reduced levels of oxygen in the blood. Hence,
breathing rate would be increased in the patients with sepsis. Normal respiratory rate in an
adult should be between 12 to 20 breaths per minute; however, in case of Kirkman observed
respiratory rate was between 35 breaths per minute. Urinary tract infection is associated with
reduced urine output mainly because body goes into the shock. It led to reduced blood flow to
the organs including kidney. It results in the reduced glomerular filtration; hence, it results in
reduced cardiac output. Hence, in patients with urinary tract infection, urine output gets
reduced. In case of Kirkman also, urine output reduced. Reduced urine output results in the
reduced excretion of elements like Na+, K+ and Cl-. Hence, there would be increased levels of
these electrolytes in patients with urinary tract infection. In case of Kirkman also, there was
slight increase in the electrolyte concentration. WBC count in sepsis patients increased due to
infection and inflammation. WBC count increase in patients with sepsis to fight against
infection. Infection activates immune system and increase number of white blood cells to
destroy infection. Different types of white blood cells act differently to fight against
infection. Lymphocytes produces antibodies to fight against bacteria in sepsis patients.
Neutrophils act as powerful destroyer of bacteria. Basophils play role in alerting body about
infection by releasing chemicals in the blood stream. Macrophages increase in the sepsis
patients to remove damaged tissue due to infection and regulate immune response (McLellan
and Hunstad, 2016).
Nursing strategy:
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In case of Kirkman, indwelling catheter was inserted. Catheter is one of the most significant
risk factors for exaggeration of urinary tract infection. It has been estimated that
approximately 80 % cases with indwelling catheter were associated with UTI. Hence,
effective nursing strategy need to be implemented for providing care to patients with UTI.
Nurses should not operate catheter unless trained for its operation. Nurses need to insert
catheter when indicated and it need to be removed at the earliest. Nurses need to maintain
effective hand hygiene. Moreover, nurses need to use gloves during use of catheter. Nurses
need to avoid needless irrigation because it has not been proved useful to reduce bacteriuria
(Willson et al., 2009).
It is necessary to maintain closed drainage system because opening would allow entry of
bacteria and subsequently infection. During collection of specimns also; closed system should
be maintained. Specimen sample should be collected through needle and port should be
cleaned with 70% isopropyl alcohol. Nurse should perform meatal care at least twice daily
through use of soap and water. Nurse should ensure that insertion site of catheter should be
cleaned with povidone iodine and antibiotic ointment (Parker et al., 2009). It should be
ensured that catheter is secured. Securing the catheter would be helpful in the preventing
meatal, urethral irrigation, tension of catheter, bladder-neck trauma and urethral tearing.
Securing catheter would also be helpful in reducing patient’s discomfort and reduce the risk
of inadvertent dislodgement. Kinks of the tubing need to be checked which would be helpful
in eliminating urine flow obstruction to the drainage bag. Collecting bag should be kept
below bladder level which would be helpful in preventing backflow of contaminated urine.
Catheter need to be inserted by two technically skilled nurses. Two patients with catheters
should not be housed in the same room because there might be chances of cross-
contamination during handling catheters simultaneously for both the patients. Nurses should
ensure that catheters are not being changed regularly when it is working properly because it
would increase risk of bladder and urethral trauma. Nurse need to assess the patient on
regular basis to ensure whether catheter is necessary for the patient (Fink et al., 2012).
Arterial blood gas :
It is necessary to corelate demographic and clinical history because it would be helpful in
providing clue related to the current acid-base assessment. In normal ABD, pH and paCO2
usually change in the opposite direction and HCO3- and paCO2 change in the same direction.
Metabolic problem occurs when pH and paCO2 alters in the same direction. Respiratory
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problem occurs when pH and paCO2 alters in the opposite direction and paCO2 is normal. In
case of Kirkman, pH and paCO2 alters in the same direction. It indicates, Kirkman is
associated with metabolic problem because both alters in the same direction. Both pH and
paCO2 values are less than normal in case Kirkman. pH in Kirkman indicate academia. Mere
decrease in paCO2 should be considered as the respiratory alkalosis. However, condition of
Kirkman should considered as respiratory acidosis because both pH and paCO2 reduced in
him. HCO3- changes corresponding to the change in paCO2 (Rogers and McCutcheon, 2015).
In case of Kirkman, it has been observed that there was more decrease in HCO3- relative to
decrease in paCO2. It indicates respiratory acidosis. These results are in alignment with the
results of pH and paCO2 (Larkin and Zimmanck, 2015; Rogers and McCutcheon, 2013).
Infection lead to reduced level of haemoglobin in Kirkman. Reduced level of haemoglobin
results in the decreased oxygen carrying capacity. Hence, there is reduced PaO2. Reduced
levels of PaO2 in Kirkman lead to increased breathing rate. Patients with UTI are associated
with reduced volume of urine. Reduced urine volume results in reduced lactate excretion.
Hence, there would be increase in the lactate level in blood. In case of Kirkman also, it has
been observed that lactate content increased (Larkin and Zimmanck, 2015; Rogers and
McCutcheon, 2013).
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References:
Anderberg, S.B., Luther, T., and Frithiof, R. (2017). Physiological aspects of Toll-like
receptor 4 activation in sepsis-induced acute kidney injury. Acta Physiologica, 219(3),
573-588.
Detweiler, K., Mayers, D., and Fletcher, S.G. (2015). Bacteruria and Urinary Tract Infections
in the Elderly. Urologic Clinics of North America, 42(4), 561-8.
Fink, R., Gilmartin, H., Richard, A., Capezuti, E., Boltz, M.,…Wald, H. (2012). Indwelling
urinary catheter management and catheter-associated urinary tract infection
prevention practices in Nurses Improving Care for Healthsystem Elders hospitals.
American Journal of Infection, 40(8), 715-20.
Haak, B.W., and Wiersinga, W.J. (2017). The role of the gut microbiota in sepsis. Lancet
Gastroenterology & Hepatology, 2(2), 135-143.
Larkin, B.G., and Zimmanck, R.J. (2015). Interpreting Arterial Blood Gases Successfully.
Association of periOperative Registered Nurses Journal, 102(4), 343-54.
McLellan, L.K., and Hunstad, D.A. (2016). Urinary Tract Infection: Pathogenesis and
Outlook. Trends in Molecular Medicine, 22(11), 946-957.
Pop-Began, V., Păunescu, V., Grigorean, V., Pop-Began, D., and Popescu, C. (2014).
Molecular mechanisms in the pathogenesis of sepsis. Journal of medicine and life,
7(2), 38-41.
Parker, D., Callan, L., Harwood, J., Thompson, D.L., Wilde, M.,…and Gray, M. (2009).
Nursing interventions to reduce the risk of catheter-associated urinary tract infection.
Part 1: Catheter selection. Journal of Wound Ostomy & Continence Nursing, 36(1),
23-34.
Rogers, K.M., and McCutcheon, K. (2015). Four steps to interpreting arterial blood gases.
Journal of Perioperative Practice, 25(3), 46-52.
Rogers, K.M., and McCutcheon, K. (2013). Understanding arterial blood gases. Journal of
Perioperative Practice, 23(9), 191-7.
Stapleton, A.E. (2014). Urinary tract infection pathogenesis: host factors. Infectious Disease
Clinics of North America, 28(1), 149-59.
Willson, M., Wilde, M., Webb, M.L., Thompson, D., Parker, D.,…and Gray, M. (2009).
Nursing interventions to reduce the risk of catheter-associated urinary tract infection:
part 2: staff education, monitoring, and care techniques. Journal of Wound Ostomy &
Continence Nursing, 36(2), 137-54.
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