What is the best course of action for a patient with a history of kidney stones, presenting with severe low back and side pain, radiating to the right side, nausea, and difficulty breathing, who was treated with Toradol (ketorolac) and Flexeril (cyclobenzaprine) in the emergency department (ED) and discharged with a prescription for Flexeril (cyclobenzaprine)?

Critical Management Failure: This Patient Was Likely Misdiagnosed and Inappropriately Discharged

This patient's presentation is highly concerning for an acute kidney stone (nephrolithiasis) rather than musculoskeletal back pain, and discharging her with only Flexeril represents a significant management error that could lead to serious complications including obstructive uropathy, infection, and acute kidney injury.

Why This Was Likely a Kidney Stone, Not Musculoskeletal Pain

The clinical presentation strongly suggests renal colic:

• Excruciating unilateral flank pain radiating to the side is the hallmark of kidney stones, not muscle strain 1, 2
• Pain described as "worst pain ever experienced" with severity of 10/10 is characteristic of renal colic 3, 4
• Inability to find comfortable position is pathognomonic for kidney stones (patients typically writhe in pain), whereas musculoskeletal pain improves with positioning 3
• Severe nausea is present in the majority of kidney stone patients 3, 4
• History of previous kidney stones dramatically increases likelihood of recurrent stones 1, 2
• Dramatic response to Toradol (ketorolac) - NSAIDs are first-line therapy specifically for renal colic because they reduce ureteral spasm and inflammation 1, 2, 5

Critical Diagnostic Omissions

The emergency department failed to perform essential diagnostic workup:

• No urinalysis was documented - over 80% of kidney stone patients have hematuria, and its absence should prompt consideration of alternative diagnoses 3
• No imaging was obtained - this patient required urgent imaging (CT or ultrasound) to rule out obstructing stone, hydronephrosis, or other serious pathology 3, 1
• No assessment for infection - while afebrile, infected obstructed kidney is a urological emergency requiring immediate decompression 1, 2

Why the Discharge Plan Was Inappropriate

Flexeril (Cyclobenzaprine) is the Wrong Medication

Cyclobenzaprine is a muscle relaxant indicated only for musculoskeletal conditions, not renal colic 6:

• It has no role in kidney stone management and will not address the underlying pathophysiology of ureteral spasm 1, 2
• It provides only sedation without treating the cause of pain 6
• It has significant anticholinergic side effects and CNS depression 6
• The patient already received appropriate therapy (Toradol) in the ED but was not given continuation therapy

Correct Acute Management Should Have Been:

NSAIDs are first-line therapy for acute renal colic 1, 2:

• The European Association of Urology recommends NSAIDs (diclofenac, ibuprofen, or ketorolac) as first-line treatment due to superior efficacy over opioids 1, 2
• Ketorolac inhibits ureteral contractility and reduces inflammation 5
• The patient should have been discharged with oral NSAIDs (ibuprofen 600-800mg every 6-8 hours or diclofenac 50mg every 8 hours), not Flexeril 1, 2

However, NSAIDs must be used cautiously:

• Ketorolac is contraindicated in patients with advanced renal impairment or at risk for renal failure due to volume depletion 7
• Maximum duration of ketorolac use is 5 days due to renal, GI, and cardiac toxicities 3, 7
• Patients can develop acute renal failure or hyperkalemia, especially with pre-existing risk factors 8, 9
• This patient's renal function should have been checked before NSAID continuation

What Should Have Been Done

Immediate ED Management:

1. Urinalysis - to document hematuria and rule out infection 3
2. Non-contrast CT scan or renal ultrasound - to identify stone location, size, and degree of obstruction 3, 1
3. Basic metabolic panel - to assess renal function and electrolytes before continued NSAID use 2, 7
4. If stone confirmed:
   • Stones >5mm in distal ureter: prescribe alpha-blocker (tamsulosin 0.4mg daily) for medical expulsive therapy 1, 2
   • Discharge with oral NSAIDs (NOT Flexeril) for pain control 1, 2
   • Strain urine to capture stone for analysis 3, 2
   • Increase fluid intake to achieve >2.5L urine output daily 2

Admission Criteria (Any of These Warrant Hospitalization):

• Failure to achieve pain control within 1 hour 3
• Signs of infection (fever, elevated WBC) - requires urgent decompression via nephrostomy or stent 1, 2
• Solitary kidney or bilateral obstruction 1
• Acute kidney injury 1, 2
• Intractable nausea/vomiting preventing oral intake 3
• Stones >10mm (unlikely to pass spontaneously) 2

Appropriate Follow-up:

• Urology referral within 7 days for confirmed stones, not just "PCP follow-up in a few days" 3
• Return precautions: severe recurrent pain, fever, inability to urinate, or persistent vomiting 3
• Maximum 4-6 weeks of conservative management before intervention if stone doesn't pass 2

Common Pitfalls Demonstrated in This Case

• Anchoring bias - assuming "lifted heavy objects" = musculoskeletal injury without considering alternative diagnoses 3
• Failure to obtain basic diagnostic tests (urinalysis, imaging) in a patient with classic renal colic presentation 3
• Prescribing inappropriate medication (muscle relaxant for suspected kidney stone) 1, 2
• Inadequate discharge planning - no specific instructions for urine straining, hydration, or urgent urology follow-up 3, 2
• Not recognizing that dramatic response to ketorolac is diagnostic - NSAIDs work specifically on renal colic pathophysiology 1, 5

Immediate Action Required

This patient needs urgent callback and proper workup:

• Contact patient immediately to assess current symptoms
• Arrange urgent imaging (CT or ultrasound) within 24-48 hours
• Discontinue Flexeril and prescribe appropriate NSAID therapy (after confirming normal renal function)
• Provide proper discharge instructions for kidney stone management
• Arrange urology follow-up within 7 days, not just PCP follow-up 3, 2

The combination of history of kidney stones + classic renal colic presentation + dramatic response to ketorolac makes this diagnosis nearly certain, and the failure to pursue appropriate workup and treatment represents a significant deviation from standard of care 3, 1, 2.