Pyelonephritis / Renal Calculi

Scenario 

You are called to A+E to see Mrs Johnson, a 45-year-old woman, presenting with a 4 day history severe right sided back pain and urinary symptoms. She appears unwell, with temperature spikes starting today and tachycardia on initial observations, you have been asked to see her directly due to the A+E being overran. 

Observations

Respiratory rate 21

Oxygen saturation 98% on RA 

Heart rate 120 BPM

Blood pressure 150/70 mmHg

Temperature 39.2C

How would you initially assess this patient? 

Upon receiving the call to assess the patient, I would take the following steps in an A-E approach and CCrISP triple assessment. 

Airway

• Assess for any signs of airway obstruction

Breathing

• Place patient on 15L non-rebreather mask

• Monitor oxygen saturation and respiratory rate

• Look for cyanosis or increased work of breathing

• Perform focused respiratory examination including trachea, percussion, expansion, and auscultation

• Obtain ABG/VBG to look for lactate

Circulation

• Assess warmth and perfusion

• Monitor blood pressure and heart rate 

• Perform focused cardiovascular examination including pulse regularity, blood pressure, jugular venous pressure (JVP), heart sounds, and signs of overload

• Review urine output and fluid balance

• Establish intravenous access

• Perform blood tests including FBC, U+Es, LFTs, CRP 

• Obtain an ECG as tachycardic

Disability

• Assess Glasgow Coma Scale (GCS)

• Check blood glucose levels

• Evaluate pupil responses

• Monitor temperature and consider blood cultures if indicated

Exposure 

• Review limbs for evidence of DVT

• Review cannula sites for evidence of cellulitis

• Examine abdomen for tenderness / peritonitis

If concerned about the patient's condition state you would initiate SEPSIS SIX and promptly inform a senior colleague for further assessment and management.

What are your potential differential diagnoses for this patient? 

For a patient presenting with severe back pain and urinary symptoms like Ms. Johnson, potential differential diagnoses can be categorised into urological, gastrointestinal, vascular and gynaecological aetiologies:

Urological

• Pyelonephritis

• Urinary tract infection (UTI)

• Renal calculi

• Cystitis

• Ureteral obstruction

Gastrointestinal

• Acute appendicitis

• Diverticulitis

• Pancreatitis / cholecystitis 

Vascular

• Aortic dissection

• Renal artery thrombosis / infarction

Gynaecological

• Rupture ectopic / ovarian cyst

• Endometriosis

What initial bedside tests and haematological investigations would you order in this patient?

Bedside Tests

• ABG or VBG: Assess for acidosis and lactate levels, indicating tissue ischemia.

• Urine Dipstick: Quickly assess for signs of urinary tract infection (UTI) or haematuria.

• Blood cultures: as likely septic

Blood Tests

• FBC: Evaluate for signs of infection (e.g. elevated WCC / CRP) 

• U&Es: Check for electrolyte abnormalities and acute renal failure

• LFTs: Assess liver function particularly as likely to start on IV Abx 

• CRP: Measure to assess for systemic inflammation and potential sepsis.

Scenario: The patient has radiating loin to groin pain (right sided flank pain to RIF) his dipstick was positive for blood and CRP is 250 with WCC 14. She describes urinary symptoms of frequency, urgency and dysuria starting 5 days ago.

What do you think is going on? 

Given the constellation of symptoms and findings, including radiating flank pain, haematuria, elevated inflammatory markers, and urinary symptoms, acute pyelonephritis complicated by renal calculi is the most likely diagnosis. 

How would you initially treat this patient in A+E? 

For the initial treatment of the patient, following the principles of the Sepsis Six protocol (BUFALO mneumonic), the key steps would include:

B  Blood Cultures

U  Urine Output 

F  Fluids

A Abx

L Lactate

O  Oxygen

• Blood Cultures: Collect blood cultures from two different sites.

• Urine Output: Catheterise and monitor urine output

• Fluids: Initiating rapid IV fluid resuscitation with crystalloid solution.

• Abx: Initiating empiric broad-spectrum antibiotics targeting likely pathogens causing pyelonephritis, such as Escherichia coli.

• Lactate: Monitor lactate levels if there are signs of systemic illness or shock.

• Oxygen: Administering supplemental oxygen if the patient is hypoxic.

Ensure prompt senior clinical review and admission to hospital for further management.

What further radiological investigation would you order?

CT-KUB 

• Non-contrast CT of the kidneys, ureter and bladder 

• Gold Standard for investigation of ureteric stones 

CT KUB shows a right sided 4mm mid-ureteric stone. What further surgical intervention may be required in this patient? 

In cases where a patient presents with an infected obstructed urinary system, such as acute pyelonephritis with a ureteric stone, further surgical intervention may be necessary to relieve obstruction and facilitate drainage of infected urine. The two main surgical options in this scenario are nephrostomy tube placement and ureteric stent insertion. 

Nephrostomy Tube Placement

• Procedure: Tube insertion into renal pelvis through flank.

• Indications: Severe ureteric obstruction, infected obstructed system.

• Advantages: Rapid relief, direct drainage, bedside procedure.

• Disadvantages: Ongoing catheter/tube care, discomfort, risks of bleeding or infection.

Ureteric Stent Insertion

• Procedure: Flexible stent placed into ureter.

• Indications: Ureteric obstruction, pyelonephritis.

• Advantages: Relieves obstruction, minimally invasive.

• Disadvantages: Stent-related symptoms, migration, complications.

What is a calculi? 

An abnormal solid collection / stone that has precipitated within a duct or organ. 

The commonest sites include:

• Gallbladder and biliary tree (gallstones)

• Urinary system 

• Pancreas

• Prostate

• Salivary glands (sialolithiasis) 

Where along the renal tract are common sites for stones to become obstructed?

• Pelvi-ureteric junction (PUJ)

• Pelvic Brim

• Vesico-ureteric junction (VUJ)

Note: pelvic brim is where the ureters cross over the iliac vessels

What is the most common composition of renal calculi?

Calcium containing stones. Calcium Oxalate most common 

What are the most common organisms for UTI/pyelonephritis? 

The three most common causes of urinary tract infections are: 

• Escherichia coli (E. coli): This bacterium is the most common cause of UTIs, accounting for approximately 80-85% of uncomplicated cases and a significant proportion of pyelonephritis cases.

• Klebsiella pneumoniae: Another common Gram-negative bacterium that can cause UTIs, especially in patients with underlying conditions such as diabetes mellitus or structural abnormalities of the urinary tract.

• Proteus mirabilis: Known for its ability to form urinary tract stones, Proteus mirabilis is a common cause of complicated UTIs and is frequently associated with urinary catheterisation.

Which infections increase risk of stones? How does this occur? 

Proteus 

Klebsiella

Mycoplasma

These organisms have the enzyme urease. Urease involved in the hydrolysis of urea. Results in ammonia formation. The resultant  alkaline conditions  result in the formation of large struvite stones.

Note: Increased pH (alkaline conditions) predisposes to the formation of struvite stones

What are the potential consequences of a renal calculi?

• Haematuria 

• Ongoing renal colic

• Obstruction leading to hydronephrosis / hydroureter

• Infection 

  • Leading to infected system (pyelonephritis + sepsis)

• Malignant transformation

  • Rare

  • Squamous cell carcinoma formation

    
    

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