Low Back Pain

• New Bladder / Bowel / Saddle Symptoms?
  • Assess sacral function.
  • Preserved walking or urination does not exclude CES
• New Substantial OR Progressive Motor Weakness?
  • Urgent imaging + spine consult
  • Even in one root distribution without bladder symptoms
• Conus / Cord?
  • A sensory level or findings beyond lumbar roots require assessment of a higher lesion

• Examination + PVR
  • Document the deficit
  • Bladder scanning supports the assessment—not clearance
• Suspected CES → emergency MRI
  • Do not wait for consultant approval, retention, or a PVR measurement
• Severe / Progressing Deficits Or Imaging / Transfer Delays
  • Involve the spine team early

• Compression Explains The Deficit
  • Immediate spine consult
  • Definitive treatment / transfer
• Tumor / Infection / Hemorrhage
  • Start cause-specific treatment while arranging definitive care
• MRI Does Not Explain The Deficit
  • Reassess the level, scan adequacy, and other causes of weakness / retention

• Repeat motor, sensory, and bladder findings
  • Communicate deterioration immediately
• OR / Spine Center
  • Confirmed compression requiring definitive treatment—not a routine bed request
• Continued Evaluation / Admission
  • Significant deficits, retention, or emergency assessment remain unresolved
• Discharge
  • No unresolved emergency, safe function, and a clear follow-up plan

• Anatomy: The cord ends in the upper lumbar spine.
  • Lumbar and sacral roots continue as the cauda equina, supplying the legs and pelvic organs.
  • CES is a nerve-root problem—not necessarily cord compression. AANS — Cauda Equina Syndrome
• CES: Sacral-root dysfunction, particularly S2 and below, affecting bladder, bowel, saddle sensation, or sexual function.
  • Back pain, sciatica, and weakness may accompany it but are not required.
  • Preserved walking or urination does not exclude CES. Lavy 2022
• Cause: Often a large central lumbar disc herniation.
  • A smaller lesion may matter in an already narrowed canal.
  • Other causes include tumor, epidural infection, hemorrhage, and trauma.
  • CES describes the dysfunction; imaging establishes whether compression explains it. AANS — Causes

• Radicular Pain / Sciatica: Radiating leg pain from root irritation.
  • Weakness is not required.
• Radiculopathy: Root dysfunction causing corresponding sensory loss, weakness, or reflex change.
  • CES involves sacral dysfunction—not simply worse sciatica or more affected roots. Lavy 2022
• New Substantial OR Progressive Motor Weakness
  • Urgent imaging + spine consult, even in one root distribution without bladder symptoms.
  • “Not CES” does not mean “no important compression.” AANS — Herniated Disc

• Conus: The terminal cord produces overlapping leg / sacral findings.
  • The examination may not distinguish conus disease from CES.
  • Imaging establishes the level. WFNS 2024
• Sensory Level / Findings Beyond Lumbar Roots
  • Assess for a proximal cord lesion and adjust imaging.
  • Do not stop at lumbar MRI when the examination points elsewhere.

• Bladder
  • New difficulty starting, altered urge or awareness of flow, weak stream, straining, incomplete emptying, or painless retention.
  • Ask what changed—not simply “any incontinence?”
• Saddle / Genitals
  • New numbness around the anus, perineum, or genitals.
  • Altered sensation when wiping may be the first clue.
• Bowel / Sexual Function
  • New loss of rectal-fullness sensation, bowel control, or sexual function.
  • Ask directly.
• Legs
  • New substantial or progressive weakness, worsening gait, or bilateral / multiple-root symptoms.
  • Unilateral symptoms or preserved strength do not exclude sacral dysfunction.
• Context / Trajectory
  • Document onset and progression, including changes from chronic symptoms.
  • Review spinal procedures, anticoagulation, infection, cancer, and trauma.
  • A plausible urinary explanation does not override concerning neurologic findings. Lavy 2022 · Hennessy 2025 — Pathway Review

• Incomplete CES: Neurogenic urinary difficulty with voluntary emptying preserved.
  • Altered sensation, weak stream, or straining may precede retention.
• CES With Retention: Loss of voluntary bladder control with painless retention and possible overflow leakage.
  • Leakage does not establish normal emptying.
• Do Not Wait For Retention
  • These categories describe severity—not referral requirements.
  • Saddle or other sacral symptoms may precede urinary failure.
  • PVR alone does not establish the stage. Lavy 2022

• Legs
  • Compare strength, sensation, reflexes, and gait when safe.
  • Distinguish pain-limited effort from objective weakness.
  • Document the deficit and examination limitations.
• Sacral Function
  • Assess perineal sensation with consent.
  • Record reported changes even when testing is normal or incomplete.
  • Document bladder function before catheterization when feasible.
    • Do not delay necessary drainage. HSE — National CES Guideline
• Rectal Tone: Normal tone does not exclude CES.
  • Pathways differ on routine examination.
  • It must not delay MRI / referral or serve as a clearance test. Tabrah 2022 · GIRFT 2026

• Measure After Voiding
  • Obtain promptly when feasible.
  • Interpret with urinary symptoms and the neurologic examination.
  • ≥200 mL: Raises concern but does not diagnose CES.
  • <200 mL: Lowers probability but does not exclude incomplete CES.
• MRI Decision
  • A low PVR does not clear a concerning presentation.
  • Do not delay indicated MRI for bladder measurements. Boktor 2023

Journal Club — PVR Is An Adjunct

• Katzouraki 2020
  • In a prospective cohort of 260 suspected cases, PVR ≥200 mL had 94.1% sensitivity. Katzouraki
• Boktor 2023
  • A meta-analysis found 82% pooled sensitivity at the 200-mL threshold. Boktor
  • Different populations and methods limit comparison; neither supports a universal clearance cutoff.
• Todd 2022
  • A selected medicolegal series included 13 definite incomplete-CES cases with PVR ≤200 mL, all requiring emergency decompression.
  • This demonstrates CES despite low PVR—not its frequency in an unselected ED population. Todd

• Suspected CES → Emergency MRI
  • Do not wait for consultant approval or progression to retention.
  • Involve spine early for severe / progressing deficits or imaging / transfer delays. WFNS 2024 · GIRFT 2026 — MRI
• Protocol
  • Lumbar MRI without contrast for suspected disc-related compression.
  • Adjust contrast / coverage for infection, tumor, prior surgery, or findings suggesting another level. ACR/RSNA — Low Back Pain Imaging
• MRI Unavailable / Contraindicated
  • Urgent transfer or a radiology / spine-directed alternative, sometimes CT myelography.
  • A reassuring plain film or routine CT does not replace the necessary compression assessment. ACR/RSNA
• Interpretation: Match imaging to the syndrome.
  • A disc protrusion alone does not establish CES.
  • An adequate MRI without explanatory compression argues against surgically treatable compressive CES.
    • Persistent weakness or retention still needs an explanation. GIRFT 2026 — Imaging Outcome

• Compression Explains The Deficit
  • Immediate neurosurgical / orthopedic spine consult + urgent decompression planning.
  • Transfer when definitive treatment is unavailable locally.
• Timing
  • Do not use 24–48 hours as permission to wait.
  • Retention or delayed presentation does not make assessment futile.
  • Timing alone cannot guarantee recovery. WFNS 2024

• Prepare
  • Analgesia
  • NPO if urgent surgery is possible
  • Necessary preoperative tests—without delaying imaging or transfer. GIRFT 2026
• Retention
  • Catheterize significant retention.
  • Document preceding symptoms and retained / drained volume.
  • Do not delay necessary drainage for a PVR assessment. HSE — National CES Guideline
• Serial Examination
  • Repeat motor, sensory, and bladder findings.
  • Time-stamp and communicate deterioration during imaging / transfer.

• Level / Study
  • Was the relevant anatomy adequately imaged?
  • A sensory level or more proximal findings require assessment beyond the lumbar roots.
• Other Causes
  • Review urinary obstruction, medications, pain-related difficulty voiding, and other neurologic disease.
  • Persistent myelopathy without compression → neurology assessment
    • Including inflammatory causes such as transverse myelitis.
• Persistent Deficit
  • Negative lumbar MRI does not establish a functional disorder or explain progressive weakness.
  • Treat retention.
  • Reassess function.
  • Arrange appropriate specialist care.
  • Do not discharge on the scan result alone. GIRFT 2026 — Imaging Outcome

• Confirmed Compression Requiring Treatment
  • Proceed with surgery / transfer—not routine ward placement.
  • Communicate timing, progression, imaging, anticoagulants, and bladder findings. GIRFT 2026 — Referral

• Unresolved Emergency
  • Required imaging / consultation remains incomplete, or significant weakness / retention remains unexplained.
  • Monitoring does not replace timely MRI.
• Function / Treatment
  • Unsafe mobility, ongoing bladder-care needs, or required inpatient treatment.
  • The setting must support timely evaluation and escalation.

• Critical Support
  • Shock, organ-support needs, or complications requiring intensive monitoring.
  • Suspected CES alone does not mandate ICU instead of urgent MRI / spine assessment.

• Reassuring Completed Assessment
  • No unresolved emergency.
  • Manageable symptoms, safe mobility / bladder management, and a workable home plan.
  • Low PVR, normal tone, or pain relief alone is insufficient.
• Return Immediately
  • New urinary difficulty, bladder / bowel change, saddle numbness, or new substantial / worsening weakness.
  • Do not wait for scheduled follow-up. GIRFT 2026 — Safety-Netting

• Concerning Spine Pain + Infection Context: Assess SEA even without fever or weakness.
• New Neurologic Deficit / Sepsis: Resuscitate and activate urgent spine assessment. See Recognition. AHRQ — Diagnostic Pitfalls

• High Concern / New Deficit / Sepsis: Urgent MRI + spine assessment. Do not wait for ESR/CRP when imaging is indicated.
• Infection Possible, MRI Decision Uncertain? Stable neurologic examination → selective ESR/CRP to refine concern; interpret with the clinical assessment.
• Low Concern / Reassuring Examination: Routine ESR/CRP and MRI are generally unnecessary. Reassess an evolving or atypical presentation.
• Other Testing: Document neurologic function; obtain CBC, renal function, and blood cultures when spinal infection is suspected. See Diagnosis. ACR 2021 · Davis 2011

• Neurologic Compromise / Sepsis: Cultures without delay → IV antibiotics + immediate spine consultation.
• SEA Confirmed: Arrange drainage / decompression assessment; selected medical management requires specialist oversight. See Critical Actions. IDSA 2011 — MRSA / Spinal Epidural Abscess

• Repeat strength, sensation, bladder function, and perfusion; communicate deterioration immediately.
• Confirmed SEA requires admission / definitive-care planning. Do not delay needed intervention for routine ward placement. See Disposition. AANS — Spinal Infections

• SEA: Infection in the epidural space between the dura and the surrounding spinal canal. It may threaten the cord or cauda equina and cause permanent neurologic injury.
• Related Disease: Vertebral osteomyelitis involves bone; discitis involves the disc space. These may coexist with SEA, but an epidural infection can occur without either.
• How Infection Arrives: Bloodstream spread, extension from nearby infection, or inoculation during a spinal procedure. S. aureus is the leading organism. AANS — Spinal Infections
• Why Early Recognition Matters: Pain may precede weakness or sphincter dysfunction. A normal initial motor examination does not establish that the infection is harmless. AHRQ — Diagnostic Pitfalls

• Pain: New, focal, persistent, or worsening back / neck pain. Reassess repeat visits and a change from chronic pain rather than accepting the previous strain diagnosis.
• Infection Source: Recent bacteremia, especially S. aureus, skin infection, endocarditis, or an infected vascular catheter raises concern for spinal seeding. IDSA 2015 — Native Vertebral Osteomyelitis
• Procedure / Host Risk: Recent spinal injection or surgery, injection drug use, diabetes, dialysis / vascular access, or immunosuppression. No injection drug use does not exclude SEA.

• Fever: Supports infection but may be absent. Do not require fever, pain, and neurologic deficit together.

  Journal Club — Durant 2025:

  Among 457 MRI-confirmed cases, 10.7% had back / neck pain, fever, and weakness; 71% had a potentially related visit before diagnosis. This retrospective cohort supports vigilance—not MRI for every repeat visit. Durant 2025

• Neurologic Change: Radicular pain, new weakness, sensory loss, gait difficulty, urinary retention, or saddle symptoms. Progression need not follow a fixed sequence; new deficits change the urgency. AANS — Spinal Infections

• Neurologic Baseline: Compare strength, sensation, reflexes, and gait when safe. Examine the arms when cervical disease is possible; a sensory level may localize above the lumbar spine.
• Bladder / Saddle Function: Ask about new urinary difficulty, altered perineal sensation, and bowel dysfunction. PVR can support a retention assessment but does not exclude SEA; see the separate Cauda Equina section.
• Spine / Source: Assess focal tenderness, wounds, vascular access, and other infection findings. A lumbar-focused examination or scan can miss thoracic disease. AHRQ — Diagnostic Pitfalls

• CBC / Renal Function: Assess systemic illness and treatment implications. A normal WBC does not exclude spinal infection.
• Blood Cultures: Obtain two sets, preferably before antibiotics when this causes no meaningful delay. Positive cultures may establish the organism; negative cultures do not exclude infection. IDSA 2015 — Native Vertebral Osteomyelitis

• ESR / CRP — When Do They Help? Select when spinal infection remains plausible but the need for MRI is uncertain in a stable patient without a concerning neurologic deficit.

  • High Clinical Concern / New Deficit / Sepsis: Proceed with urgent MRI and spine assessment. Do not wait for inflammatory markers or use them to cancel indicated imaging.
  • Elevated Results: Support further investigation but do not establish SEA.
  • Both Low: Reduce concern when the history, examination, and trajectory are also reassuring. They may support deferring MRI after clinical reassessment—not a laboratory-only discharge rule.
  • Low Clinical Concern: A compatible benign presentation and reassuring neurologic examination generally do not require routine ESR/CRP or emergency MRI.
  • Different Diagnostic Question: Low inflammatory markers cannot exclude disc-related cauda equina compression, epidural hematoma, or another noninfectious lesion.

  Journal Club — Davis 2011:

  A risk-based pathway was associated with fewer SEA diagnostic delays. ESR sensitivity reached 100% in a selected risk-factor subgroup; the single-center, nonrandomized result is not a universal rule-out guarantee. Davis 2011.

  Journal Club — Gutovitz 2025:

  Retrospective analysis of 1,963 infectious-spine cases and 3,981 controls, all selected for inflammatory-marker testing and MRI. A combined screen using ESR ≤20 mm/hour and CRP ≤1.0 mg/dL (10 mg/L) reported 98.9% sensitivity for acute infectious spinal pathology.

  • Included SEA, discitis, osteomyelitis, and spinal septic arthritis—not SEA alone. Selection and diagnosis-code limitations apply; prospective validation is needed. Do not import these thresholds as a mandatory rule-out pathway. Gutovitz 2025.

• Preferred Study: MRI without and with IV contrast to define epidural infection and neural involvement. Noncontrast MRI remains useful when contrast cannot be obtained promptly; coordinate the protocol with radiology. ACR 2021
• Coverage: Image the clinically implicated levels; discuss broader or whole-spine coverage when localization is uncertain or multifocal disease is possible. A negative lumbar study does not exclude an unexamined thoracic lesion. AHRQ — Diagnostic Pitfalls

• CT / X-Ray: May identify bone destruction or another diagnosis but cannot reliably exclude epidural infection.

  Journal Club — Shroyer 2022:

  In a small 14-patient CT/MRI subgroup, CT detected only 2 of 11 SEAs. This is not a universal sensitivity estimate; it illustrates the danger of using a reassuring CT as clearance. Shroyer 2022

• MRI Unavailable / Nondiagnostic: Arrange urgent radiology / spine discussion and transfer when needed. Persistent deficits require reassessment of scan quality, coverage, and alternative diagnoses—not automatic discharge. ACR 2021 AHRQ — Diagnostic Pitfalls

• Lumbar Puncture: Not the diagnostic test for SEA; avoid puncturing a potentially infected epidural space. Use blood / operative cultures rather than CSF to investigate the suspected epidural infection. ACEP Now 2010 — LP Precaution

• Sepsis / Progressive Neurologic Deficit: Obtain cultures without delaying immediate IV antibiotics and spine consultation. Do not wait for biopsy or transfer before starting indicated treatment. IDSA 2015 — Native Vertebral Osteomyelitis
• Confirmed SEA, Currently Stable: Establish an urgent antibiotic and drainage plan with spine / ID. Preserved strength is not permission for routine outpatient treatment. IDSA 2011 — MRSA / Spinal Epidural Abscess UK MRSA Guideline 2021
• Biopsy-First Exception: Selected stable vertebral osteomyelitis without an epidural abscess may undergo sampling before empiric antibiotics. Do not transfer this exception automatically to SEA; any delay requires an explicit specialist plan. UCSF — Vertebral Osteomyelitis

• Initial Regimen: Cover MRSA, streptococci, and relevant gram-negative organisms.
  • Vancomycin + Ceftriaxone: A reasonable community-acquired example from UCSF's adult epidural-abscess pathway. UCSF — Epidural Abscess
  • Broader Gram-Negative Risk: Consider cefepime rather than ceftriaxone when the exposure / local resistance pattern warrants it; coordinate with ID. IDSA 2015 — Native Vertebral Osteomyelitis
• Dosing / Selection: Use the institutional serious-infection regimen with weight, renal function, allergy, and therapeutic-monitoring adjustments. Postoperative / hardware-associated infection requires its own specialist plan. UCSF — Epidural Abscess
• Culture Results: Narrow therapy and investigate the source. Duration depends on organism, drainage, associated osteomyelitis, and response—not one fixed course for every epidural abscess. IDSA 2011 — MRSA / Spinal Epidural Abscess

• Neurologic Deficit / Significant Compression: Immediate neurosurgical / orthopedic spine assessment for decompression and drainage. Do not wait for an antibiotic trial while neurologic function deteriorates. IDSA 2011 — MRSA / Spinal Epidural Abscess
• Instability / Persistent Infection: Structural instability, persistent bacteremia, or progression despite appropriate treatment also prompts operative reassessment. AANS — Spinal Infections

• Medical Management Alone: An option for selected patients after specialist review, including some small collections without deficits. It requires reliable serial examinations and immediate access to escalation—not simply antibiotics and discharge. UK MRSA Guideline 2021

  Journal Club — Shah 2018:

  Initial nonoperative treatment failed in 99 of 367 patients in a retrospective cohort. Baseline motor deficits and diabetes were among the predictors. This supports careful selection and surveillance; it does not prove that every patient benefits from surgery. Shah 2018

• Confirmed SEA: Not a routine ED discharge diagnosis. Initial inpatient treatment and specialist assessment are required.
• SEA No Longer Suspected: Discharge only after the evaluation supports a safe alternative plan, with no unresolved infection / neurologic concern. Explain immediate return for weakness, urinary difficulty, saddle symptoms, fever, or worsening pain. AANS — Spinal Infections AHRQ — Diagnostic Pitfalls

• Confirmed SEA without ICU-level support needs; arrange spine / ID assessment and serial neurologic examinations.
• Persistent substantial suspicion when required MRI or consultation is incomplete. Admission must not become a reason to postpone time-sensitive imaging. IDSA 2011 — MRSA / Spinal Epidural Abscess ACR 2021

• Shock, respiratory compromise, rapidly worsening neurologic function, or need for intensive support / surveillance.
• ICU placement does not replace urgent drainage or decompression when indicated. AANS — Spinal Infections IDSA 2011 — MRSA / Spinal Epidural Abscess

• UA: Interpret pyuria, bacteriuria, and nitrite with the symptoms and examination.
  • Bacteriuria Alone: Does not establish pyelonephritis or explain delirium. Without urinary or systemic infection findings, assess other causes. IDSA
  • A reassuring specimen does not end the assessment when infected obstruction remains suspected.
• Urine Culture: Obtain for suspected pyelonephritis, preferably before antibiotics without delaying urgent treatment. Use susceptibility results to adjust the regimen. Uroweb
• Blood Tests: Creatinine / electrolytes and CBC when clinically relevant; blood cultures / lactate for sepsis or significant systemic illness. NIDDK

• Typical Low-Risk Presentation: Usually no imaging solely to confirm pyelonephritis.
• Image Early: Suspected stone / obstruction, significant renal impairment, severe illness, or substantial complication risk. Radiologyinfo.org
• Ultrasound: Assess hydronephrosis / obstruction.
  • Unrevealing US but persistent obstruction / abscess concern → further imaging, usually CT in a nonpregnant adult. Uroweb
• CT Abdomen / Pelvis With IV Contrast: Assess renal infection complications, abscess, or an alternative diagnosis.
  • Match the protocol to the question—not automatic noncontrast stone CT. Radiologyinfo.org
• Not Improving By 48–72 Hours? Recheck the culture, antibiotic activity, and diagnosis; assess obstruction / abscess.
  • Deterioration → reassess now, not after another 48–72 hours. Uroweb

• Sepsis / Poor Perfusion: Resuscitate + IV antibiotics. Obtain cultures promptly; do not delay treatment. IDSA
• Infected Obstruction: IV antibiotics + urgent urology / IR for ureteral stent or nephrostomy.
  • Antibiotics do not relieve the obstruction. Do not delay drainage for an antibiotic trial or routine bed placement. Uroweb
• Abscess / Gas-Forming Infection: Imaging + early urology / ID assessment; source control may be required. Do not simply extend an ineffective prescription. PubMed

• Choose An Active Drug: Review severity, prior cultures, recent antibiotics, local resistance, allergies, renal function, and interactions.
  • A prior resistant organism may make ceftriaxone inadequate; broaden for the patient’s risk, then narrow to cultures. IDSA
• Oral Treatment? Selected stable, nonpregnant patient who can tolerate medication and has no unresolved obstruction / major complication.
  • Fluoroquinolone / TMP-SMX: Use when likely active and patient-specific risks permit; susceptibility should support the choice when available.
  • Oral Beta-Lactam: Selected agent at an appropriate pyelonephritis dose—not any cystitis prescription. IDSA
• Initial Parenteral Dose? Consider ceftriaxone or another appropriate long-acting agent when susceptibility is uncertain and the outpatient regimen calls for initial coverage.
  • EAU recommends this when starting TMP-SMX / an oral beta-lactam before susceptibility is known. Uroweb
  • An initial IV dose does not rescue an inactive oral course. IDSA
• IV Treatment? Sepsis, persistent vomiting, or no suitable effective oral option. Pregnancy follows the separate pathway below. IDSA
  • Improving + Tolerating PO: Transition when an effective oral option exists and any necessary source control is addressed. IDSA
• Bladder-Only Regimens: Nitrofurantoin and single-dose oral fosfomycin are not pyelonephritis treatment. IDSA

• Selected Nonpregnant Patients Improving On Effective Therapy: Count from the first effective dose.
  • Fluoroquinolone: 5–7 days.
  • Non-Fluoroquinolone: 7 days under the IDSA framework; confirm agent, dose, and patient suitability.
• Individualize: Obstruction, abscess, suspected prostatitis, severe illness, immunocompromise, significant renal disease, or other poorly represented populations.
  • Suspected prostate involvement requires a separate treatment plan—not an automatic seven-day course. IDSA

Journal Club

IDSA’s short-course recommendation has moderate-certainty evidence for fluoroquinolones and very-low-certainty evidence for non-fluoroquinolones. Short-course oral beta-lactam data remain limited. EAU is more conservative for febrile male UTI; assess prostate involvement and individualize duration. IDSA

• Suspected Pyelonephritis → OB Consultation + Initial Inpatient Treatment.
  • Parenteral antibiotics until clinically improving; select an effective pregnancy-appropriate regimen.
  • Complete 14 days total treatment under ACOG guidance—not the general short-course plan above. ACOG

• Stable / Nonpregnant: Symptoms manageable, tolerating effective oral treatment, and no unresolved obstruction / major complication.
• Home Plan: Medication access, reliable reassessment, and a culture-review plan. IDSA
• Return Immediately: Worsening illness, rigors, reduced urine, increasing pain, or inability to tolerate fluids / medication. NIDDK

• Treatment / Complication: Sepsis requiring inpatient care, unresolved obstruction, abscess, important renal dysfunction, persistent vomiting, or failed outpatient treatment.
• Pregnancy / Unsafe Home Plan: Initial inpatient obstetric care, or observation / admission when reliable outpatient treatment cannot be secured. ACOG

• Shock / Critical Support: Persistent hypoperfusion or organ-support requirements.
• Drainage Still Urgent: ICU placement does not replace source control for infected obstruction. IDSA

• UA: Assess hematuria, pyuria, and nitrites; interpret with the presentation.
  • No Hematuria: Does not exclude a ureteral stone. PubMed
  • Pyuria: May be sterile, but increases infection concern → obtain a culture. Do not automatically dismiss it as stone irritation. PubMed
• Urine Culture: Obtain when infection is suspected.
  • An abnormal UA alone does not establish infected obstruction. Strong clinical concern should not wait for culture confirmation. PubMed Central (PMC)
• Renal Function: Compare creatinine with baseline and assess urine output.
  • Review solitary functioning kidney / bilateral obstruction. Urgency depends on the functioning kidney and obstruction—not creatinine alone. Uroweb
• Pregnancy Possible? Establish pregnancy status before selecting imaging and medication.

• Ultrasound First? Selected presentations where the initial question is hydronephrosis / obstruction.
  • No visible stone does not exclude ureterolithiasis. Obtain further imaging when diagnostic or complication concerns remain. PubMed
• No Immediate Imaging? Selected uncomplicated recurrent episodes with a convincing stone pattern, controlled symptoms, and low concern for another diagnosis.
  • Requires a reassuring assessment and reliable follow-up—not stone history alone. DOI
• Noncontrast CT: Defines stone size, location, and obstruction.
  • Obtain for diagnostic uncertainty, suspected complications, or a result that will change treatment.
  • Use a reduced-radiation protocol when appropriate. PubMed
• Different Question? Suspected aortic disease or renal infection complications → the corresponding protocol, not automatic noncontrast stone CT.
• Pregnant: Ultrasound first.
  • Unresolved concern → radiology / OB / urology discussion. MRI or selected CT may be needed; pregnancy does not prohibit necessary imaging. Radiologyinfo.org

Journal Club — Ultrasound First, Not Ultrasound Only

• Smith-Bindman 2014: In 2,759 randomized patients, initial ultrasound reduced radiation without a significant increase in high-risk diagnoses with complications.
• Additional CT was allowed. This compared imaging strategies—not imaging versus no imaging. eScholarship

• Suspected Infected Obstruction: IV antibiotics + urgent urology / drainage. Obtain cultures without delaying treatment; see Infected Obstruction below.
• Kidney At Risk: Anuria, bilateral obstruction, obstruction threatening a solitary functioning kidney, or worsening renal function → urgent imaging / urology.
• Symptoms Still Uncontrolled: Persistent pain / vomiting despite treatment → reassess the diagnosis and need for intervention.
  • Do not continue a routine passage plan when infection, kidney function, or symptoms require escalation. PubMed Central (PMC)

• NSAID: First-line analgesia when renal, GI, bleeding, cardiovascular, and pregnancy-related risks permit.
  • Antiemetic as needed.
  • Persistent Severe Pain / Alternatives Unsuitable: Titrated opioid rescue with reassessment. Uroweb
• Fluids: Replace volume depletion—not an attempt to “flush out” the stone.
  • Forced hydration has no established passage benefit.
  • An isolated creatinine rise is not a reason for repeated fluid without reassessing volume status and obstruction. PubMed

• Safe To Observe? Symptoms controlled, no infection or threatened kidney function, and reliable follow-up.
  • Stone size and location help estimate passage likelihood. PubMed Central (PMC)
• Tamsulosin? Consider for a distal 5–10 mm ureteral stone suitable for a trial of passage.
  • Off-label; benefit is less convincing for very small stones likely to pass without it. Uroweb

Journal Club — Selective Benefit

• Furyk 2016: No significant overall passage benefit, but improved passage in the prespecified 5–10 mm subgroup.
• Pain and intervention rates were not significantly improved. PubMed

• Reassuring Assessment: Pain / vomiting controlled, tolerating oral intake and medication, and no unresolved infection or threatened kidney function.
• Home Plan: Medication access, reliable follow-up, and clear passage / reassessment instructions. PubMed Central (PMC)
• Return Immediately: Fever / rigors, reduced urine, worsening pain, or inability to tolerate fluids / medication. NIDDK

• Complication / Failed Symptom Control: Infected obstruction, threatened kidney function, or persistent pain / vomiting requiring inpatient care.
• Definitive Care: Urgent urology / transfer when needed. Necessary drainage or intervention takes priority over routine ward placement. PubMed Central (PMC)

• Infection Behind An Obstruction: An infected collecting system cannot drain adequately and may progress to sepsis—even with a small stone.
• Immediate Action: Urine / blood cultures + IV antibiotics + resuscitation as needed.
  • Urgent urology / IR for ureteral stent or nephrostomy.
  • Do not wait for culture results, an antibiotic trial, or routine bed placement. Antibiotics alone do not relieve the obstruction.
• Drain First: Defer definitive stone treatment until infection is controlled. Tamsulosin is not source control. Uroweb
• Urgent Intervention Without Infection? Anuria, bilateral obstruction / threatened solitary kidney, worsening renal function, or refractory symptoms → urgent urology assessment.
  • Small stone does not mean low risk when infection or kidney function is threatened.
• Shock / Organ-Support Needs: ICU-level resuscitation and urgent drainage planning proceed together. Uroweb