Kidney Infection (Pyelonephritis): Exposure Risks, Diagnosis & Treatment

A kidney infection, or acute pyelonephritis, is a bacterial infection of the renal pelvis and parenchyma. Almost all cases arise from ascending infection: uropathogens colonise the periurethral area, climb the urethra into the bladder and—when defences fail—travel up the ureters to seed the kidney. Far less commonly, the infection reaches the kidney by haematogenous spread (notably Staphylococcus aureus bacteraemia, with risk of renal cortical abscess) or by direct extension from a perinephric source.

The dominant organism is Escherichia coli, responsible for roughly three-quarters to nine-tenths of community-onset cases. Other Enterobacterales (Klebsiella pneumoniae, Proteus mirabilis, Enterobacter species), Pseudomonas aeruginosa, enterococci and Staphylococcus saprophyticus account for most of the remainder; resistant ESBL-producing strains are increasingly common in healthcare-associated and recurrent infection. Specific virulence factors—P-fimbriae and type-1 fimbriae adhesion, haemolysins, siderophores and capsular antigens—help pathogenic E. coli colonise the urothelium and survive innate immune defences.

The clinical syndrome ranges from a mildly unwell young woman with fever and flank ache who can be safely discharged on oral antibiotics, to an obstructed septic patient with rigors, hypotension and acute kidney injury who needs the sepsis pathway, urgent imaging and emergency decompression. Early international guidance (IDSA, EAU, NICE) frames management around three pivots: uncomplicated versus complicated, severity (sepsis or not), and whether the urinary tract is structurally or functionally normal—because each pivot changes the antibiotic, the route, the disposition and the urology phone call.

Two complementary frameworks anchor decision-making. The first sorts the patient by tract—is this a structurally normal urinary tract, or is something obstructing, refluxing, immunosuppressed or instrumented? The second sorts the patient by severity—are they septic, or can they go home with tablets? Both run in parallel from the first triage encounter.

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Severity scoring is supported by the same generic acute medicine tools used everywhere else: NEWS2 (UK), MEWS or MEDS in the US, qSOFA at the bedside (respiratory rate ≥22, altered mentation, systolic BP ≤90 mmHg) and lactate. None of them replace the clinician’s eye, but they catch the patient who has tipped from “unwell with a UTI” to “septic with pyelonephritis” before the obvious vital-sign collapse.

Classic acute pyelonephritis announces itself loudly: an unwell adult with rigors, a temperature ≥38°C, unilateral flank pain that radiates to the loin or groin, a tender costovertebral angle, dysuria and a sense that something is seriously wrong. Many real patients are not classic, and the variations matter clinically more than the textbook triad.

Common adult presentation

• Fever, often spiking, with chills and rigors that can shake the bed.
• Unilateral flank or costovertebral-angle pain; bedside CVA tenderness reproducible with a firm percussion of the loin.
• Painful urination, urgency and frequency in the days leading up to admission, often with a treated or untreated cystitis history.
• Nausea and vomiting heavy enough to threaten oral hydration and oral antibiotics.
• Visible blood in urine or microscopic haematuria on dipstick.
• Generalised lower back pain rather than focal flank pain in some patients—particularly older adults and those with neurogenic bladders.

Pattern-recognition clues

• The septic phenotype: rigors with hypotension, tachycardia, mottled skin and capillary refill >3 s—look for sepsis trajectory and activate the local pathway before ordering more tests.
• The obstructed phenotype: severe colicky flank pain plus rigors strongly suggests an obstructed infected kidney (an emergency) until imaging proves otherwise—classically with a known stone history or a kidney stone background.
• The pregnancy phenotype: right-sided flank pain (the right ureter is more often dilated by gravid uterus compression) plus low-grade fever is enough to admit—escalate even without florid sepsis.
• The diabetic phenotype: blunted pain perception, atypical low-grade fever, glycosuria-fed bacteriuria, and high risk of emphysematous pyelonephritis or papillary necrosis—keep diabetic patients in hospital longer.
• The catheter phenotype: new fever and rigors in an indwelling-catheter user with no other source—suspect catheter-associated pyelonephritis even when the urine looks “normal” on dipstick.

Atypical and easy-to-miss patterns

Older adults frequently present with confusion, falls, anorexia, urinary incontinence or generalised weakness rather than fever and flank pain—a urinary source can be silent until they crash. Patients with spinal cord injury, dementia or cognitive impairment may show only autonomic dysreflexia (cord injury), increased spasticity, foul or cloudy urine, or unexplained agitation. Children—particularly under 2 years—can present with fever alone, vomiting, poor feeding and irritability, and a febrile UTI in this age group is pyelonephritis until proven otherwise. Asymptomatic bacteriuria found on routine urinalysis in a patient who already feels unwell with vague systemic symptoms can be the only clue.

Risk factors fall into three buckets: things that let bacteria climb (anatomy, behaviour, instrumentation), things that let bacteria multiply (urinary stasis, glycosuria, obstruction) and things that let infection escape the immune system (extremes of age, immunosuppression, comorbidity). Identifying which buckets apply changes both the antibiotic and the disposition.

Microbiology

• Escherichia coli dominates community-onset cases (~75–90%), especially uropathogenic strains carrying P-fimbriae.
• Other Enterobacterales: Klebsiella pneumoniae, Proteus mirabilis (urease-producing, stone-prone), Enterobacter, Citrobacter, Morganella.
• Healthcare-associated: Pseudomonas aeruginosa, multidrug-resistant Enterobacterales (ESBL, carbapenemase producers), enterococci.
• Gram-positives: Staphylococcus saprophyticus in young women, Enterococcus faecalis in catheterised patients, Staphylococcus aureus with bacteraemia (look for endocarditis, IV drug use, abscess seeding).
• Less common: Candida species in catheterised, diabetic or immunocompromised patients; Mycobacterium tuberculosis in chronic sterile pyuria with classic risk factors.

Modifiable and behavioural risk factors

• Recent or recurrent urinary tract infection, especially within the previous month.
• Sexual activity (frequency, new partner, spermicide use).
• Indwelling urethral catheter, recent urological instrumentation, ureteric stent.
• Voiding dysfunction—incomplete emptying, deferred voiding habits.
• Constipation, dehydration, low fluid intake.

Structural and functional risk factors

• Urinary tract obstruction: stones, strictures, tumours, ureteropelvic junction obstruction.
• Benign prostatic hyperplasia with bladder outlet obstruction in older men.
• Vesicoureteral reflux (childhood and adult); neurogenic bladder from spinal cord injury or multiple sclerosis.
• Single functioning kidney, transplant kidney, polycystic kidney disease.
• Pregnancy (mechanical compression and progesterone-mediated ureteric dilation, peak risk in the second trimester).
• Type 2 diabetes (and type 1) with glycosuria; gestational diabetes compounding pregnancy risk.

Immune and demographic risk factors

• Extremes of age (infants, frail older adults).
• Immunosuppressive therapy, HIV with low CD4 count, post-transplant.
• Underlying chronic kidney disease—pyelonephritis is a known precipitant of acute kidney injury on chronic disease.
• Prior pyelonephritis, especially with residual renal scarring.
• Use of SGLT2 inhibitors—small but documented increase in genitourinary infection risk.

Diagnosis is clinical, supported by urine and blood investigations and—when complicated, severe or non-responsive—imaging. Aim to send the right specimens before antibiotics start, but never let specimen collection delay the first dose in a septic patient.

Bedside history checklist

• Onset, fever pattern, rigors, flank or loin pain laterality, radiation to groin.
• Dysuria, urinary frequency, urgency, haematuria, foul or cloudy urine.
• Recent UTIs, antibiotics taken (and adherence), recent hospitalisation or instrumentation.
• Pregnancy status, contraception, sexual exposures.
• Diabetes control, immunosuppression, transplant, single kidney, known stones or anatomical anomalies.
• Catheter use, intermittent self-catheterisation, recent stent or nephrostomy.
• Antibiotic allergies and recent travel (multidrug-resistance risk).

Focused examination

A structured head-to-toe assessment framed around the urinary tract: temperature, heart rate, blood pressure, respiratory rate, mental state, capillary refill, mottling. Palpate the abdomen for tenderness, masses, and a palpable bladder; percuss the costovertebral angle (a sharp percussive blow to the loin) for unilateral tenderness. Examine for signs of sepsis (mottled skin, prolonged capillary refill, fingertip cyanosis), pregnancy and dehydration. In men, examine the prostate gently for tenderness suggestive of concurrent prostatitis; in catheterised patients, inspect the catheter and meatus for purulent discharge.

Initial laboratory panel

• Urine dipstick at the bedside via a urinalysis dipstick—nitrites and leucocyte esterase support but do not confirm; a negative dipstick does not rule out pyelonephritis when symptoms are typical.
• Clean-catch midstream sample (or catheter sample port specimen) for microscopy, culture and sensitivities—see the clean-catch urine specimen collection standard. ≥10⁴ CFU/mL with pyuria typically supports diagnosis; lower thresholds matter in symptomatic women.
• Two sets of blood cultures in any febrile or septic patient—up to a quarter to a third of inpatients are bacteraemic.
• Full blood count with differential, U&E with creatinine and eGFR, CRP ± procalcitonin where used locally for stewardship.
• Lactate and venous (or arterial) blood gas if NEWS2 ≥5 or qSOFA ≥2.
• Glucose / HbA1c and ketones in suspected diabetic ketoacidosis precipitated by infection.
• Pregnancy test (β-hCG) in any person of childbearing potential.
• Coagulation panel in severe sepsis or before any procedural intervention.

Imaging—when, what, and why

Most uncomplicated pyelonephritis does not need imaging. Image promptly when the patient is septic, has a known or suspected obstruction, has a single functioning kidney, has poorly controlled diabetes with severe symptoms, is pregnant with severe disease, or has not improved within 48–72 hours of appropriate antibiotics.

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Common interpretation traps

• Negative dipstick does not exclude pyelonephritis. Symptoms beat the dipstick when the clinical picture is convincing.
• Catheter urine looks bacteriologically dirty. Asymptomatic bacteriuria in catheterised patients is common and rarely justifies treatment—anchor on systemic features and pyuria.
• Sterile pyuria with normal cultures raises suspicion for genital tuberculosis, partially treated infection, atypical organisms (Chlamydia, Ureaplasma) or interstitial cystitis.
• “Resolved” lactate after fluid resuscitation does not exclude ongoing source problems—repeat trends and re-image if fever persists.
• Procalcitonin is not magic. A reassuring level can guide stewardship but cannot overrule a sick-looking patient.

A pragmatic chain that ED, ward and primary-care teams can apply in the first 30 minutes:

1. Triage severity. NEWS2 / qSOFA / lactate decide whether the patient sits in resus or in the cubicle. Sepsis trajectory triggers sepsis screening and the local pathway immediately.
2. Decide the tract. Uncomplicated (young non-pregnant adult woman, normal tract) versus complicated (pregnancy, male, diabetes, immunosuppression, stones, instrumentation, transplant, single kidney). Complicated pyelonephritis admits more often and gets imaged sooner.
3. Send the right specimens before antibiotics. Two sets of blood cultures, a clean-catch or catheter sample-port urine, and bedside dipstick. Run U&E, creatinine, FBC, lactate, CRP and—when relevant—β-hCG and glucose.
4. Start empiric antibiotics within 1 hour for sepsis; within 4–6 hours for stable patients. IV ceftriaxone is the default inpatient empiric agent for community-onset disease in much of the world; oral fluoroquinolone is a reasonable outpatient choice when local resistance is low and the patient is well.
5. Decide oral or IV, home or admission. Stable, non-pregnant, non-diabetic adult who can tolerate oral fluids, has good follow-up and lives close to care can be discharged on oral therapy after a single observed parenteral dose. Everyone else admits.
6. Image the right ones. Septic, obstructed, diabetic with severe disease, single-kidney, pregnant with severe disease, or non-responder at 48–72 hours—contrast CT (or ultrasound first in pregnancy/children) is non-negotiable.
7. Reassess at 48–72 hours. Defervescence, falling lactate, falling CRP, clinically improved—step down to oral targeted therapy. Persistent fever, rising creatinine or worsening NEWS2—repeat imaging and rethink the antibiotic.
8. Plan the back-end. Total course typically 7 days for fluoroquinolones, 10–14 days for beta-lactams, longer for complicated infection, abscess or pregnancy. Refer to urology after recovery for any obstruction, abscess, recurrent disease, paediatric first febrile UTI, or pyelonephritis in a male.

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Management runs three rails: kill the bug, support physiology, and remove obstruction. The first dose of an appropriate empiric antibiotic is the single most consequential intervention in the first hour.

Empiric antibiotic choice

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Always confirm empirical choices against local antibiograms—community fluoroquinolone resistance in many regions now exceeds 10–15%, and oral fluoroquinolone monotherapy without an initial parenteral dose is no longer recommended in those areas. Nitrofurantoin and oral fosfomycin do not achieve adequate renal tissue concentrations and should not be used for pyelonephritis.

Supportive therapy

• IV fluids. Balanced crystalloid (Hartmann’s, Plasma-Lyte) to restore perfusion in sepsis; avoid hyperchloraemic bolus stacks; titrate to mean arterial pressure ≥65 mmHg, urine output ≥0.5 mL/kg/h and falling lactate.
• Antipyretics and analgesia. Acetaminophen / paracetamol 1 g every 4–6 hours up to 4 g/day; NSAIDs cautiously when renal function and sepsis allow; opioids reserved for breakthrough flank pain.
• Antiemetics. Ondansetron, metoclopramide or cyclizine to enable oral switch; document intake and watch QT in cardiac patients.
• Glycaemic control. Tighten in inpatients with diabetes—hyperglycaemia worsens outcomes; insulin sliding scale only when needed and per local protocol.
• Venous thromboembolism prophylaxis. Mechanical and pharmacological per usual inpatient pathway unless contraindicated.

Source control

Antibiotics alone do not save an obstructed kidney. Decompression with a retrograde ureteric stent or percutaneous nephrostomy is the priority intervention in obstructed pyelonephritis—do not delay surgical input awaiting antibiotic effect. Renal or perinephric abscesses larger than 3–5 cm typically need image-guided drainage; emphysematous pyelonephritis frequently requires percutaneous drainage and may require nephrectomy. Catheter removal or replacement is the source-control step in catheter-associated infection.

Step-down and duration

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Pregnancy

Pyelonephritis complicates 1–2% of pregnancies and is the most common non-obstetric reason for admission in pregnancy. Right-sided disease predominates because the dextrorotated gravid uterus compresses the right ureter, and progesterone-mediated ureteric dilation provides a ready-made conduit for ascending infection. Treat any febrile UTI in pregnancy as upper-tract: admit, IV ceftriaxone 1–2 g daily, fetal monitoring, low threshold for obstetric review and imaging with ultrasound first. Step down to oral cefalexin or co-amoxiclav based on sensitivities to complete a 10–14 day course. Avoid fluoroquinolones (cartilage), tetracyclines (teeth, bone), trimethoprim in the first trimester (folate antagonism) and nitrofurantoin near term (haemolysis risk). Screen and treat asymptomatic bacteriuria at the booking visit—it halves the risk of pyelonephritis in pregnancy. Recurrent disease in pregnancy may warrant prophylactic antibiotics until delivery and a postnatal urology review.

Paediatric considerations

Febrile infants under 3 months and children under 2 with an unexplained fever need a urine sample collected by clean-catch, in-out catheter or suprapubic aspiration—bag samples are unreliable. E. coli dominates here too. UK and US paediatric guidelines (NICE NG224, AAP) recommend ultrasound of the kidneys and urinary tract for atypical or recurrent UTI, with selective DMSA and micturating cystourethrography depending on age and the imaging pathway. Empirical therapy starts with IV cefotaxime or ceftriaxone (avoiding ceftriaxone in neonates with hyperbilirubinaemia) and oral step-down based on sensitivities; total courses run 7–10 days. Refer all children with a first febrile UTI to paediatric urology for assessment of vesicoureteral reflux. Careful explanation to parents about safety-netting (return for new fever, vomiting, lethargy) is part of the discharge bundle.

Older adults

Frail older adults often present with delirium, falls, anorexia, urinary incontinence or unexplained tachypnoea rather than fever and flank pain. Asymptomatic bacteriuria is extremely common in this group and should not be treated reflexively—treatment is appropriate only when there are systemic features attributable to a urinary source. NEWS2 ≥5 in any older adult deserves a same-shift senior review. Avoid nephrotoxic combinations (gentamicin plus NSAIDs plus contrast), watch QT prolongation with fluoroquinolones, and review cognitive status before discharge. Catheter-associated pyelonephritis is a major driver of admission—urinary catheterization indications should be challenged at every shift, and removal is the highest-value source-control intervention you will make all day.

• Document the time to first antibiotic. Record the dose, route and time on the drug chart and observation chart—the audit trail matters legally and operationally.
• Send cultures from the right source. A catheter sample taken from the sample port (after disinfection) is acceptable; the bag is not. Replace long-dwelling catheters before sampling when feasible.
• Reconcile antibiotics carefully. A formal medication reconciliation at admission catches recent OTC, recurrent-UTI prophylaxis and over-the-counter cranberry/D-mannose use that changes both expectations and resistance patterns.
• Track intake and output. Hourly urine output ≥0.5 mL/kg/h is a quick proxy for kidney perfusion in sepsis; document fluid in, urine out and lactate every 1–2 hours during resuscitation.
• Plan the IV-to-oral switch. A timed switch when the patient has been afebrile 24–48 hours, is clinically stable and has sensitivities back avoids unnecessary line days, reduces phlebitis risk and shortens stay.
• Stewardship at every step. De-escalate to the narrowest active agent once cultures return; document why broad-spectrum is being continued if cultures fail to identify a target.
• Anticipate AKI. Sepsis, contrast load, NSAIDs and aminoglycosides stack risk—monitor creatinine daily and adjust drug doses to renal function; review nephrotoxic medications.
• Plan handover meticulously. Use a structured nursing handoff covering current empiric agent, cultures pending, fluid status, source-control plan and escalation criteria.
• Refer urology after recovery for any obstruction, recurrent pyelonephritis (≥2 episodes in 6 months or ≥3 in 12 months), pyelonephritis in a male, abscess or emphysematous pyelonephritis, anatomical anomalies or paediatric first febrile UTI.

Vital signs and systemic check

• Routine vital signs measurement with NEWS2 / qSOFA every 1–4 hours during the acute phase—track temperature, heart rate, respiratory rate, blood pressure, SpO₂ and conscious level.
• Hourly urinary output measurement during resuscitation—target ≥0.5 mL/kg/h.
• Capillary blood glucose every 4 hours (or per protocol) in any patient with diabetes—pyelonephritis can precipitate diabetic ketoacidosis.
• Daily creatinine, U&E and CRP; serial lactate every 2–4 hours during sepsis until cleared.

Source-specific assessment

• Flank pain score (0–10) and side every 4 hours—worsening or migrating pain may flag abscess, obstruction or stone passage.
• Inspect the catheter site (if present), bag and urine appearance every shift; document colour, clarity, sediment and any foul odour.
• Check antibiotic timing on the drug chart at every round—missed or delayed doses are a frequent driver of treatment failure.
• Tolerance of oral intake, antiemetic effect and signs of dehydration (mucous membranes, capillary refill, postural drop).

Red flags requiring escalation

• NEWS2 ≥5 or qSOFA ≥2—activate rapid response and senior review.
• Lactate ≥2 mmol/L despite a 30 mL/kg crystalloid bolus, or rising lactate on serial measurement.
• Persistent fever >72 hours despite appropriate antibiotics—repeat imaging for abscess or obstruction.
• Rising creatinine ≥1.5× baseline or oliguria <0.5 mL/kg/h—evolving acute kidney injury.
• New confusion, agitation or asterixis in a patient previously alert and oriented.
• New onset uterine contractions, fetal distress or vaginal bleeding in pregnancy.

Acute

• Urosepsis and septic shock. Up to a quarter to a third of inpatients are bacteraemic; mortality rises sharply with delayed antibiotics, persistent obstruction or comorbidity.
• Acute kidney injury. Sepsis, dehydration, NSAIDs, contrast and nephrotoxic antibiotics stack to drive AKI; track creatinine daily.
• Renal or perinephric abscess. Suspect when fever persists beyond 72 hours; image, drain and prolong antibiotics.
• Emphysematous pyelonephritis. Necrotising infection in poorly controlled diabetes; emergency drainage with high mortality.
• Papillary necrosis. Particularly in diabetes, sickle-cell disease and analgesic nephropathy; can present with passage of necrotic papillae and sterile pyuria.
• Preterm labour, fetal compromise or miscarriage in pregnancy—obstetric input is mandatory.
• Catheter-associated complications: blockage, bypassing, urethral injury, ongoing infection.

Long-term

• Chronic pyelonephritis with renal scarring, hypertension and progressive chronic kidney disease.
• Recurrent pyelonephritis—particularly in patients with stones, reflux or persistent obstruction.
• Reduced renal function in survivors of severe disease, especially when AKI was prolonged or required renal replacement therapy.
• Antimicrobial resistance developing within an individual patient through repeated antibiotic exposures.

Several drivers are genuinely modifiable. Treat asymptomatic bacteriuria at the booking visit in pregnancy—evidence supports a halving of pyelonephritis risk. In recurrent UTI, post-coital low-dose antibiotic prophylaxis, vaginal oestrogen therapy in postmenopausal women, methenamine hippurate where licensed, and behavioural advice (adequate fluid intake, post-coital voiding, complete bladder emptying) all have a role. Tighten glycaemic control in patients with diabetes; review SGLT2 inhibitor exposure if recurrent genitourinary infection emerges. Remove or replace indwelling urinary catheters at every clinical opportunity—catheter days drive catheter infections. Ensure timely treatment of obstructive uropathy: stones, prostatic obstruction, neurogenic bladders and ureteral strictures all warrant proactive urology follow-up. Vaccinate eligible patients against influenza and pneumococcus; while this is not pyelonephritis-specific, it reduces the overall sepsis burden in vulnerable groups. In paediatric care, treat first febrile UTI promptly and refer for imaging assessment per local pathways.

Outlook in uncomplicated pyelonephritis is excellent: prompt antibiotics defervesce most patients within 48–72 hours, and short oral or IV-to-oral courses cure most disease without sequelae. Mortality in hospitalised adults is generally low (around 1–3%) but climbs to 10–20% in urosepsis with shock, and emphysematous pyelonephritis carries reported mortality of 20–40%. Recurrent pyelonephritis affects a meaningful minority and is strongly associated with structural anomalies, stones and inadequate first-episode treatment. Long-term renal function recovery is the rule in adults with normal baseline kidneys; in patients with pre-existing chronic kidney disease, single kidneys, transplant kidneys or paediatric scarring patterns, even one severe episode can leave a measurable footprint. Setting realistic expectations early—particularly about the duration of fatigue (1–2 weeks is normal), the timing of follow-up cultures, and the urology pathway when warranted—prevents the “I’m not better yet” follow-up call that often masks unresolved infection.

Subtle deterioration

The patient who is silently slipping rarely complains loudly. Watch for the cluster: respiratory rate creeping from 18 to 22, a pulse that has gone from 92 to 110 between sets, a urine bag that has stopped filling, a sodium that has slipped two points, mottling at the knees, and a quietly rising lactate on the second gas. Pyelonephritis with obstruction frequently announces itself as “the patient just isn’t right yet”—repeat imaging is rarely wasted in a non-responder.

Communication friction

Patients who have had recurrent UTIs often arrive expecting “another tablet” and may push back against admission. Clear language helps: explain that this episode has features that put the kidneys themselves at risk, that the first dose of IV antibiotics within an hour halves the risk of bad outcomes, and that monitoring overnight is the safest path. Document refusal of admission carefully when it occurs, with senior decision-making and a written safety-net plan.

Bedside checklist

• Two sets of blood cultures from separate sites in any febrile patient before the first antibiotic.
• Time-stamp the first dose of IV antibiotic and the time of the sepsis pathway activation on the observation chart.
• Confirm catheter status, indication and removal plan at every shift change—drive a daily catheter-out review.
• Audit the antibiotic against local antibiograms and against returning sensitivities—escalate or de-escalate, do not coast.
• Loop the next team in via a structured handover with the diagnosis, severity score, source-control status and escalation criteria.

Initial bundle: ABCDE primary survey, IV access × 2, two sets of blood cultures, urinalysis with reflex culture, FBC, U&E, lactate, blood gas, glucose, β-hCG and coagulation. First dose of broad-spectrum IV antibiotic within an hour for any septic patient. Balanced crystalloid 30 mL/kg titrated to perfusion targets, vasopressors via central access if hypotension persists, and early surgical/urology contact for any imaging suggestion of obstruction or abscess. Document timings, escalation conversations and senior names.

Nursing-priority lens (NCSBN Clinical Judgment Measurement Model): recognise cues → analyse cues → prioritise hypotheses → generate solutions → take safe action → evaluate outcomes. These NCLEX-style clinical judgment practice items mix Priority FIRST, SATA, deterioration trends, multi-patient assignment, ordered response, matrix matching and cloze completion across acute pyelonephritis triage, antibiotic selection, urosepsis recognition, pregnancy escalation and obstruction-driven decision-making—matched to the Clinical Judgment Measurement Model arc of recognising cues before acting.