What is the diagnosis for a patient with urinary frequency, dysuria, and pain with pressure on the bladder, who has a history of rheumatoid arthritis (RA) and a family history of systemic lupus erythematosus (SLE), had temporary relief with amitriptyline (tricyclic antidepressant) and has normal urinalysis (UA), culture, and ultrasound results?

Diagnosis: Interstitial Cystitis/Bladder Pain Syndrome

This patient has interstitial cystitis/bladder pain syndrome (IC/BPS), definitively diagnosed by the combination of chronic bladder pain with urinary frequency and dysuria lasting more than six weeks, normal urinalysis and culture excluding infection, normal imaging excluding structural pathology, and temporary symptom relief with amitriptyline—a known effective treatment for IC/BPS. 1, 2

Why This is IC/BPS and Not the Other Options

Diagnostic Criteria Met

• Pain, pressure, or discomfort perceived to be related to the bladder with associated lower urinary tract symptoms (frequency, dysuria) present for more than six weeks in the absence of infection or other identifiable causes—this is the exact AUA definition of IC/BPS 1
• Normal urinalysis, negative culture, and normal ultrasound effectively exclude infectious cystitis, and when chronic urinary symptoms persist with normal studies, IC/BPS should immediately be suspected 2, 3
• Temporary relief with amitriptyline is highly characteristic, as amitriptyline is an established oral therapy for IC/BPS with variable but documented effectiveness, particularly in patients with bladder pain and frequency 4, 5

Why Not the Other Diagnoses

Acute bacterial cystitis is excluded because the urinalysis and urine culture are normal—UTI requires positive culture and typically shows pyuria on urinalysis 1, 6

Chlamydia and gonorrhea are excluded because these sexually transmitted infections would present with vaginal discharge, cervicitis on examination, and positive testing; they do not cause isolated bladder pain with normal urinalysis 3

Bladder cancer is excluded because the ultrasound is normal (would show an intraluminal mass), the patient lacks the classic presentation of painless hematuria (80% of bladder cancer patients), and bladder cancer does not respond to amitriptyline 1

Clinical Context Supporting IC/BPS

Relevant Medical History

• Rheumatoid arthritis and family history of SLE are significant because IC/BPS commonly coexists with other autoimmune and systemic conditions including Sjögren's syndrome, fibromyalgia, and irritable bowel syndrome, suggesting possible systemic dysregulation 1
• History of depression treated with amitriptyline that provided temporary bladder symptom relief is diagnostically important—amitriptyline at doses of 25-100 mg is therapeutically useful for bladder pain and frequency syndromes, with durable response requiring maintained dosing 5

Physical Examination Findings

• Lower abdominal tenderness to palpation is consistent with bladder/pelvic pain characteristic of IC/BPS 1, 2
• No costovertebral angle tenderness excludes pyelonephritis and upper tract pathology 3, 6

Management Approach

Confirm Diagnosis

• Document symptom duration of at least six weeks with negative cultures to meet diagnostic criteria 1, 2
• Consider voiding diary to assess baseline symptom severity before initiating therapy 2
• Cystoscopy is NOT routinely indicated unless Hunner lesions are suspected, as it is not required for diagnosis and should be reserved for specific indications 1, 2

Treatment Algorithm

First-line treatments (most conservative, appropriate at any point):

• Behavioral modifications including dietary changes and stress management 1
• Oral medications: Restart amitriptyline (since it provided temporary relief), pentosan polysulfate, or hydroxyzine—these are more effective when given together 1, 4
• Pain management should be considered throughout therapy with the goal of maximizing function and minimizing pain 1

Treatment principles:

• Multiple simultaneous treatments may be considered based on symptom severity and patient preferences 1
• Ineffective treatments should be stopped and diagnosis reconsidered if no improvement occurs within a clinically meaningful timeframe 1
• Treatments progress from conservative to more invasive only after other options have failed, with surgical treatment reserved for end-stage disease 1

Important Pitfall

Do not confuse IC/BPS with recurrent UTI—the key distinguishing feature is that IC/BPS has consistently negative cultures despite chronic symptoms, whereas recurrent UTI requires documented positive cultures with each symptomatic episode 1, 2, 3