What are the differential diagnoses for abdominal pain that worsens with urination?

Differential Diagnosis of Abdominal Pain That Worsens with Urination

Abdominal pain that worsens with urination most commonly indicates interstitial cystitis/bladder pain syndrome (IC/BPS), urinary tract infection (UTI), or in men, chronic prostatitis/chronic pelvic pain syndrome (CP/CPPS). 1

Primary Urologic Causes

Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS)

• Pain that worsens with bladder filling or improves with urination is a defining characteristic of IC/BPS, distinguishing it from other bladder conditions 1
• Patients typically describe suprapubic pain, pressure, or discomfort perceived to be related to the bladder, often accompanied by urinary frequency and urgency 1
• Pain may radiate throughout the pelvis—including the urethra, lower abdomen, and back—and is often described as "pressure" rather than pain 1
• IC/BPS patients void to avoid or relieve pain, whereas overactive bladder patients void to avoid incontinence 1
• Symptoms must persist for more than 6 weeks in the absence of infection or other identifiable causes 1
• Standard urine cultures are negative, and antibiotic therapy offers no relief, which helps distinguish IC/BPS from recurrent UTI 2, 3

Urinary Tract Infection (UTI)

• Dysuria (pain during urination) is the hallmark symptom of lower UTI, with >90% accuracy for UTI diagnosis in young women when not accompanied by vaginal discharge 4
• Suprapubic tenderness and urinary frequency are characteristic of cystitis 4, 5
• Fever, chills, flank pain, and costoverteboral angle tenderness suggest upper UTI (pyelonephritis) rather than simple cystitis 4, 5
• Bladder spasms may occur in severe infections 4

Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS) in Men

• Pain in the perineum, suprapubic region, testicles, or tip of the penis that is exacerbated by urination or ejaculation characterizes CP/CPPS 1
• Voiding symptoms include sense of incomplete bladder emptying and urinary frequency 1
• Clinical characteristics of CP/CPPS overlap significantly with IC/BPS in men, and some patients meet criteria for both conditions 1

Secondary Non-Urologic Causes

Gastrointestinal Pathology

• Left-sided colonic diverticulitis can mimic renal colic and present with flank/abdominal pain 6, 7
• Inflammatory bowel disease may manifest with abdominal discomfort that coincidentally worsens during voiding 6, 7
• Gastroenteritis and colitis can cause diffuse abdominal pain 6, 7

Gynecologic Conditions in Women

• Benign adnexal masses can cause lower abdominal pain 6, 7
• Pelvic congestion syndrome may present with chronic pelvic pain 6, 7
• Endometriosis shares symptom overlap with IC/BPS, and many women have both conditions simultaneously 8, 9

Musculoskeletal Causes

• Pain occurring after prolonged static positioning suggests paraspinal muscle or facet joint pathology 6
• Musculoskeletal pain is typically position-dependent and worsens with movement 6, 7

Critical Diagnostic Approach

Initial Evaluation

• Obtain urinalysis with microscopy and urine culture to distinguish UTI from IC/BPS 6, 9
• More than 20% of patients with confirmed urinary stones have negative urinalysis, so absence of hematuria does not exclude urologic pathology 6
• Perform beta-hCG testing in all women of reproductive age before imaging 6

Imaging Strategy

• Non-contrast CT abdomen/pelvis is the gold standard, with 98-100% sensitivity and specificity for stones, and identifies alternative diagnoses in approximately one-third of patients 6, 7
• Ultrasound is first-line in pregnant patients to avoid radiation exposure 6
• Reserve contrast-enhanced CT for suspected complicated infections (pyelonephritis, perinephric abscess) with fever and systemic symptoms 6

Key Clinical Pitfalls to Avoid

• Do not assume all patients with dysuria and frequency have UTI—IC/BPS is frequently misdiagnosed and treated inappropriately with repeated courses of antibiotics 2, 3, 8
• Do not attribute symptoms to asymptomatic bacteriuria, which is common in older adults and should not be treated without localized urinary symptoms 4
• Pain quality distinguishes conditions: IC/BPS patients describe constant pressure that improves with voiding, whereas UTI causes sharp dysuria during the act of urination 1, 4
• In women with delayed menses, do not miss ectopic pregnancy—obtain beta-hCG before attributing symptoms to bladder pathology 6

Red Flags Requiring Urgent Evaluation

• Fever, chills, or signs of systemic infection suggest obstructive pyelonephritis or urosepsis and mandate immediate imaging and possible admission 6, 4, 5
• Inability to urinate or decreased urine output indicates complete obstruction requiring urgent intervention 6
• Hemodynamic instability or shock requires emergent evaluation 6