Urinary tract infection - Nursing Case Study
Pathophysiology
• Primary mechanism: Bacterial invasion and colonization, often by Escherichia coli, in the urinary tract lead to the adherence of bacteria to the uroepithelial cells, initiating infection. The fimbriae of E. coli facilitate attachment and evasion of host defenses.
• Secondary mechanism: Inflammatory response activation results from the recognition of bacterial components by the immune system, which releases cytokines and recruits neutrophils, causing symptoms like dysuria and urgency.
• Key complication: If untreated, the infection can ascend to the kidneys, causing pyelonephritis, characterized by flank pain, fever, and potential renal damage, emphasizing the importance of early detection and management.
Patient Profile
Demographics:
45-year-old female, office administrator
History:
• Key past medical history: Recurrent urinary tract infections, hypertension
• Current medications: Lisinopril 10 mg daily, over-the-counter cranberry supplements
• Allergies: Penicillin
Current Presentation:
• Chief complaint: Increased urinary frequency and urgency
• Key symptoms: Dysuria, lower abdominal pain, mild fever, nausea
• Vital signs: Temperature 100.6°F, blood pressure 145/90 mmHg, heart rate 102 bpm, respiratory rate 20 breaths per minute
Section 1
As the nurse conducts an initial assessment, further information is gathered to build upon the existing clinical picture. The patient reports increased severity of her symptoms over the past 48 hours, particularly noting the escalation of her dysuria and lower abdominal pain. On physical examination, palpation of the suprapubic region elicits tenderness, and the patient grimaces, indicating discomfort. The patient's back is also examined, revealing mild tenderness over the right costovertebral angle, raising concerns about possible kidney involvement.
Laboratory results soon return, providing crucial insights. The urinalysis shows cloudy urine with a significant presence of leukocytes, nitrites, and moderate hematuria, confirming the presence of a bacterial infection, likely E. coli. The white blood cell count is elevated at 15,000/mm³, suggestive of an ongoing systemic inflammatory response. Given her history of recurrent urinary tract infections and the absence of penicillin as a treatment option due to her allergy, the healthcare team considers alternative antibiotics, such as a fluoroquinolone, while weighing the risks and benefits based on her current health status.
As the patient’s situation unfolds, her vital signs are closely monitored, revealing a persistent fever of 101°F and a slightly elevated heart rate of 110 bpm. This collection of data suggests the infection may be progressing towards pyelonephritis. The healthcare team must now deliberate on the most effective intervention strategy, considering both pharmacological treatment and supportive care, to prevent further complications like renal damage or sepsis. The next steps involve initiating appropriate antibiotic therapy and ensuring adequate hydration to facilitate recovery, while also planning for follow-up to monitor treatment effectiveness and prevent recurrence.
Section 2
As the medical team initiates treatment with a fluoroquinolone, the patient is also advised to increase her fluid intake to promote renal clearance and help flush the bacteria from her urinary tract. Despite these interventions, over the next 24 hours, her condition shows signs of deterioration. Her fever spikes to 102.5°F, and she begins to experience chills and rigors, indicating that the infection might be advancing despite the antibiotic therapy. Her heart rate further increases to 120 bpm, and her blood pressure drops slightly to 100/65 mmHg, raising concerns about potential systemic involvement and the risk of progressing to sepsis.
Additional laboratory tests are conducted to provide a clearer picture of her condition. A repeat complete blood count reveals a further elevation in white blood cell count to 18,500/mm³, and a blood culture is positive for E. coli, confirming bacteremia. The elevated lactate level of 3.0 mmol/L is particularly concerning, suggesting issues with tissue perfusion and a possible transition towards septic shock. These findings prompt the healthcare team to reassess the current treatment plan, considering the need for a broader-spectrum antibiotic to target the resistant strain of bacteria, as well as the initiation of intravenous fluids to stabilize the patient's hemodynamic status.
Given the patient's worsening condition, the team considers transferring her to a higher level of care for closer monitoring and more aggressive management. This includes the potential use of vasopressors if her blood pressure continues to decline. The clinical reasoning at this stage involves evaluating the effectiveness of the current antibiotic regimen, assessing for potential sources of infection that may not have been initially addressed, and considering the patient's overall risk factors for sepsis, such as her recurrent UTIs and current immunological response. The team plans to conduct further imaging studies to rule out complications such as an abscess or obstructive uropathy that could be contributing to the persistent infection.
Section 3
As the patient is transferred to the intensive care unit for closer monitoring, the medical team focuses on stabilizing her hemodynamic status while reassessing her treatment plan. Her vital signs upon arrival show a continued fever of 102°F, a heart rate of 130 bpm, and a blood pressure of 95/60 mmHg, indicating a further decline in her condition. Her respiratory rate has increased to 24 breaths per minute, and she appears visibly distressed and fatigued. Physical examination reveals mild tenderness in the suprapubic region, and her skin is cool and clammy to the touch, raising concerns about adequate circulation and perfusion.
New imaging studies, including an abdominal ultrasound, are performed to investigate any underlying complications contributing to her persistent infection. The ultrasound reveals mild hydronephrosis, suggesting a possible obstruction in the urinary tract, which may be exacerbating her condition. Additionally, the presence of a small perinephric fluid collection raises the possibility of a developing abscess. These findings necessitate a multidisciplinary approach to determine the best course of action, which may include interventional radiology consultation for potential drainage or further surgical evaluation.
In response to these developments, the healthcare team initiates a change in the antibiotic regimen to a broader-spectrum intravenous antibiotic, such as piperacillin-tazobactam, to address the potentially resistant strain of E. coli. Intravenous fluids are administered more aggressively to support her blood pressure and improve renal perfusion. The team discusses the need for vasopressors if her blood pressure fails to respond adequately to fluid resuscitation. The presence of the perinephric fluid collection also prompts consideration for placement of a nephrostomy tube to relieve the obstruction and facilitate drainage. Recognizing the complexity of her condition, the medical team continues to closely monitor her response to these interventions, with frequent reassessments to determine if further escalation of care is necessary.
Section 4
As the patient remains in the intensive care unit, the healthcare team closely monitors her response to the aggressive interventions. Over the next several hours, her vital signs show some changes: her fever persists at 101°F, her heart rate decreases slightly to 120 bpm, but her blood pressure remains low at 92/58 mmHg despite aggressive fluid resuscitation. Her respiratory rate remains elevated at 22 breaths per minute, and her oxygen saturation is stable at 94% on room air. The patient's overall appearance is still concerning; she is lethargic and continues to exhibit signs of discomfort and fatigue. Her skin remains cool and clammy, which, along with her vital signs, suggests ongoing hemodynamic instability.
Laboratory results provide further insight into her condition. Her white blood cell count has risen to 18,000/mm³, indicating a persistent or worsening infection. Serum lactate levels are elevated at 4.2 mmol/L, which is indicative of tissue hypoperfusion and ongoing sepsis. Additionally, her renal function appears to be deteriorating, with serum creatinine increasing to 2.1 mg/dL. These lab findings suggest that despite the change in antibiotic therapy and fluid resuscitation, the patient's condition is not improving as expected. The team decides to initiate a low-dose vasopressor, specifically norepinephrine, to support her blood pressure and improve perfusion.
Given the possibility of an obstructive process contributing to her hemodynamic instability and persistent infection, the interventional radiology team is consulted to evaluate the feasibility of placing a nephrostomy tube. This intervention aims to decompress the urinary tract and potentially drain the perinephric fluid collection. The decision to proceed with this intervention is made swiftly, as relieving the obstruction could significantly improve her renal function and overall condition. The healthcare team continues to reassess the patient's status, recognizing the critical nature of timely intervention and the need for ongoing multidisciplinary collaboration.
Section 5
As the interventional radiology team successfully places the nephrostomy tube, there is an immediate partial drainage of the obstructed urinary tract, and the collected fluid is sent for culture and sensitivity testing. Over the next few hours, the healthcare team closely monitors the patient's response to this intervention. Her blood pressure begins to show slight improvement, rising to 98/60 mmHg, and her heart rate stabilizes further at 110 bpm. However, her fever persists, and her oxygen saturation dips to 90% on room air, prompting the team to provide supplemental oxygen via nasal cannula. The patient's level of consciousness remains concerning, as she is still lethargic but somewhat more responsive than before.
New diagnostic results reveal that the fluid drained from the nephrostomy tube is heavily colonized with Escherichia coli, sensitive to the current antibiotic regimen. This finding confirms that the source of infection is indeed urinary, likely complicated by the obstructed flow. The team is cautiously optimistic, as the targeted antibiotics should help control the infection now that the obstruction is relieved. Nonetheless, the elevated serum lactate at 3.8 mmol/L, although slightly decreased, indicates ongoing tissue hypoperfusion, necessitating continued vasopressor support and close monitoring of renal function.
Despite these developments, a new complication arises. The patient exhibits signs of acute respiratory distress, with an increased respiratory rate of 28 breaths per minute and bilateral crackles on auscultation, suggesting fluid overload or an evolving acute respiratory distress syndrome (ARDS). Chest X-ray confirms bilateral infiltrates, which are consistent with pulmonary edema. The clinical team must now reevaluate her fluid management strategy and consider the need for diuretics or further respiratory support, such as non-invasive ventilation, to address her deteriorating pulmonary status. This new challenge underscores the importance of dynamic clinical reasoning and adaptation of the treatment plan to address the evolving complexities of her condition.