Severe Sepsis from a Urinary Tract Infection

A urinary tract infection can look straightforward until the patient starts showing signs that the infection is affecting the whole body.

This scenario follows Margaret, an older adult admitted with urinary symptoms who becomes acutely unwell. Work through what you notice, what worries you and what you would escalate as a student nurse. You do not need to make the final diagnosis. Your job is to recognise deterioration, assess safely and get help quickly.

👤 Meet Margaret

Margaret is an older adult who has been admitted with symptoms consistent with a urinary tract infection. She has felt increasingly unwell, with urinary symptoms, reduced oral intake and worsening weakness.

During your shift, Margaret appears much more unwell than earlier. She is drowsier, looks flushed and is struggling to engage with you in her usual way.

Before you read on, what are you already thinking about?

What you need to know first

Urinary tract infections can range from lower urinary tract infection to infection involving the kidneys. In some patients, infection can trigger sepsis, a life-threatening organ dysfunction caused by a dysregulated response to infection.

Older adults may not always present with a neat textbook picture. New confusion or altered mental state can occur during acute illness, but it is not specific to urinary infection and should trigger assessment for possible underlying causes rather than an assumption that a UTI is responsible.

A useful student-nurse habit is to look for a pattern. Abnormal respiratory rate, oxygen saturation, circulation, temperature, urine output and mental state together can tell you far more than one observation in isolation.

Margaret now

On assessment, Margaret is visibly unwell.

Her observations show physiological deterioration, with fever, tachycardia, hypotension and an increased respiratory rate. Her mental state has changed from baseline and her urine output has reduced.

The exact numbers matter, but the bigger lesson is the pattern: suspected infection plus new physiological and cognitive deterioration needs urgent escalation.

What should make you uncomfortable here?

Margaret is not simply a patient with urinary symptoms anymore.

The combination of suspected infection, altered mental state, circulatory compromise and reduced urine output raises concern for sepsis and possible organ dysfunction. Hypotension may indicate impaired perfusion, while reduced urine output can be a warning sign of renal hypoperfusion or acute kidney injury.

Do not wait until you can prove exactly what is happening before escalating. Recognition comes before diagnosis.

A–E assessment

A – Airway

Check that Margaret’s airway is patent and assess whether her reduced level of alertness is affecting her ability to protect it. If the airway becomes threatened, escalate immediately and call for emergency help according to local policy.

B – Breathing

Assess respiratory rate, oxygen saturation, work of breathing and chest movement. Apply oxygen if clinically indicated and prescribed or permitted under the relevant emergency/local protocol, using the documented target saturation range. For most acutely unwell adults without risk of hypercapnic respiratory failure, the usual target is 94–98%.

An increased respiratory rate can be an early sign of deterioration even when the primary source of infection is not respiratory.

C – Circulation

Assess heart rate, blood pressure, capillary refill, peripheral temperature and urine output. Ensure IV access and prescribed investigations or treatment are supported within your competence and under appropriate supervision.

Blood tests in suspected sepsis commonly include lactate, full blood count, renal function and other investigations guided by the clinical picture. Blood cultures may be required before antimicrobial therapy when this does not cause harmful delay.

If Margaret is hypotensive or showing signs of poor perfusion, urgent senior clinical assessment is required. IV fluid management must be individualised, particularly in older adults and people with cardiac or renal comorbidity.

D – Disability

Assess Margaret’s level of consciousness, orientation and blood glucose. Establish whether the confusion or drowsiness is new by checking her baseline with the patient, notes, family or carers where appropriate.

New altered mental state in an acutely unwell patient is a red flag. Do not label it as ‘just confusion’ or assume that age explains it.

E – Exposure

Check temperature and assess Margaret fully while maintaining privacy and dignity. Look for signs that may help identify the source of infection and for other causes of deterioration. Review hydration, skin integrity, pain and any urinary catheter or devices if present.

What happens next?

Margaret requires urgent escalation to the registered nurse and appropriate medical team using the organisation’s deterioration and sepsis pathway.

If her condition meets local criteria for emergency response, activate that response without delay. NEWS2 can support recognition and escalation, but clinical concern should be escalated even if a score does not appear as high as expected.

As a student nurse, you are not expected to diagnose sepsis independently, prescribe antibiotics or decide the fluid resuscitation plan. You are expected to notice deterioration, perform and communicate an A–E assessment within your competence, escalate promptly and continue reassessment while help arrives.

Treatment is guided by the patient’s condition and may include oxygen where indicated, blood tests and cultures, IV antimicrobials, IV fluids and source control. Current UK sepsis guidance uses risk stratification and patient-specific assessment rather than treating every patient with suspected infection identically.

Medicines and treatment: what the student needs to notice

Antimicrobial treatment should follow local antimicrobial guidance and consider likely source, previous microbiology, allergies, renal function and risk of resistant organisms.

During significant acute illness, regular medicines may need review. Drugs that affect renal function, blood pressure or fluid balance, and medicines whose safety changes during dehydration or acute kidney injury, may require temporary adjustment by an appropriate prescriber.

Do not independently stop regular medicines as a student nurse. Notice the issue, check the prescription and raise it with the registered nurse or prescriber.

SBAR example

S: “I’m calling about Margaret on the acute medical ward. She was admitted with a suspected urinary tract infection and I’m concerned that she is acutely deteriorating with hypotension and a new change in mental state.”

B: “She has had urinary symptoms, reduced oral intake and increasing weakness. She is now much more drowsy and unwell than earlier in the shift.”

A: “Her observations have deteriorated with fever, tachycardia, hypotension and an increased respiratory rate. Her urine output has reduced and her mental state is different from baseline. I’m concerned about sepsis and impaired perfusion.”

R: “Please review her urgently. I’ll stay with her, continue the A–E assessment, repeat observations and support the local sepsis pathway while urgent review is arranged.”

Documentation example

“Patient reviewed following acute deterioration. Suspected urinary infection with new altered mental state, reduced urine output and abnormal physiological observations. A–E assessment commenced. Concern escalated immediately to RN/medical team and local deterioration/sepsis pathway followed. Repeat observations and ongoing reassessment continued. Prescribed investigations and treatment supported within student scope and under supervision.”

Your actual documentation must include the real observations, times, people contacted, actions taken and Margaret’s response. Never document an intervention before it has happened.

Your turn

1. Which changes would make you concerned that Margaret’s infection has become a systemic emergency?
2. Why is new confusion important but not enough on its own to diagnose a urinary tract infection?
3. What would you prioritise during your A–E assessment?
4. What information belongs in your urgent SBAR?
5. What can you safely do as a student nurse while urgent review is being arranged?

Answers & rationale

1. Which changes are concerning?

Hypotension, tachycardia, increased respiratory rate, altered mental state, reduced urine output, abnormal temperature and other signs of poor perfusion are concerning when they occur in a patient with suspected infection.

Rationale: sepsis is about infection associated with acute organ dysfunction. A pattern of physiological deterioration is more important than waiting for one single ‘sepsis number’.

2. Why does the confusion matter?

New confusion may indicate acute illness, hypoxia, impaired perfusion, metabolic disturbance, medication effects, pain, dehydration or delirium from many possible causes.

Rationale: confusion should prompt assessment, not diagnostic shortcutting. In older adults, bacteriuria is common and a positive urine test does not automatically prove that a UTI is the cause of delirium.

3. What should you prioritise in A–E?

Work systematically from airway through exposure, treating or escalating life-threatening problems as they are found. Pay particular attention to respiratory status, circulation and perfusion, consciousness, blood glucose, temperature and urine output.

Rationale: A–E provides a structured way to identify immediate threats without becoming distracted by the presumed diagnosis.

4. What belongs in the SBAR?

State immediately that Margaret is deteriorating. Give the suspected infection, relevant background, current observations, change in mental state, urine output and other significant assessment findings. Finish with a clear request for urgent review.

Rationale: the person receiving the handover needs to know what has changed, why you are worried and what response is needed.

5. What can the student nurse contribute?

Stay with Margaret, perform assessment within competence, repeat observations, escalate concerns, communicate clearly, obtain equipment, support prescribed investigations and treatment under supervision, monitor urine output and fluid balance, reassure Margaret and keep reassessing her.

Rationale: recognising deterioration and speaking up are core patient-safety skills. You do not need to prescribe or make the final diagnosis to make an important contribution.

Think beyond the observations

Margaret may be frightened, confused and unable to explain what she needs in the way she normally would. Speak calmly, orientate her to where she is and what is happening, and involve family or carers appropriately if this helps establish her baseline and supports communication.

Acute confusion does not automatically mean lack of capacity. Capacity is decision-specific and may fluctuate. Follow the relevant legal framework for the UK nation in which you are practising and local policy.

Once the immediate deterioration is controlled, think about why Margaret became unwell and what will reduce the risk of it happening again. Hydration, continence, catheter care where relevant, medicines, mobility, cognition and support at home may all form part of discharge planning.

Bleepbook takeaway

Do not get stuck on the label ‘UTI’.

If a patient with suspected infection becomes hypotensive, tachycardic, more breathless, confused or oliguric, look at the whole picture. Start A–E, escalate early and keep reassessing.

For a student nurse, noticing that the patient is no longer behaving or looking like they did earlier can be the moment that matters.

References and further reading

National Institute for Health and Care Excellence (NICE) (2025). Suspected sepsis in people aged 16 or over: recognition, assessment and early management (NG253). NICE NG253

National Institute for Health and Care Excellence (NICE) (2023, updated). Urinary tract infection (lower): antimicrobial prescribing (NG109). NICE NG109

National Institute for Health and Care Excellence (NICE) (2024). Pyelonephritis (acute): antimicrobial prescribing (NG111). NICE NG111

Royal College of Physicians (2017). National Early Warning Score (NEWS) 2: Standardising the assessment of acute-illness severity in the NHS. Royal College of Physicians

British Thoracic Society (2017). Guideline for oxygen use in adults in healthcare and emergency settings. British Thoracic Society