Genitourinary Disorders: Diagnosis and Management
Urinary tract infections, hematuria, nephrolithiasis, urinary incontinence, acute kidney injury, and rhabdomyolysis require prompt recognition of key symptoms and appropriate diagnostic testing for optimal management.
Urinary Tract Infections (UTIs)
Diagnosis
- UTI diagnosis requires BOTH urinary symptoms AND laboratory evidence of pyuria and bacteriuria (≥50,000 CFU/mL of a uropathogen) 1
- UTIs are classified as:
- Uncomplicated UTI (cystitis): Localized to bladder with symptoms of dysuria, frequency, urgency, suprapubic pain, without vaginal discharge
- Complicated UTI (pyelonephritis): Extension beyond bladder with systemic symptoms (fever, chills, CVA tenderness)
Special Populations with Complicated UTIs
- Males with UTI
- Poorly controlled diabetes
- Pregnancy
- Children or elderly
- Immunocompromised patients
- Recurrent UTIs
- Kidney stones or obstruction
- Indwelling catheter
Diagnostic Testing
- Urinalysis: Leukocyte esterase (83% sensitivity, 78% specificity) and nitrite test (53% sensitivity, 98% specificity) 1
- Combined positive test (either leukocyte esterase OR nitrite): 93% sensitivity, 72% specificity 1
- Urine culture indicated for:
- Suspected pyelonephritis
- Complicated UTI
- Recurrent UTIs
- Symptoms not resolving within 48 hours
- Pregnant women
Treatment
- First-line for uncomplicated UTI: Cephalexin (also safe in pregnancy) 2
- Nitrofurantoin: Good for uncomplicated UTIs in non-pregnant females but avoid if:
- Pyelonephritis is suspected
- Creatinine clearance <30
- Pregnancy (first trimester if possible, and after 36 weeks)
- Asymptomatic bacteriuria requires treatment ONLY in pregnancy 1
Hematuria
Classification
- Gross hematuria: Visible to naked eye
- Microscopic hematuria: ≥3 RBCs per high-power field
Evaluation
- Patients >35 years with unexplained hematuria have increased risk of malignancy (85% of bladder cancer presents with hematuria)
- Workup should include:
- Urinalysis
- Urine culture and sensitivity
- Urine cytology
- Referral to urology for patients >35 years or with risk factors
Causes
- UTI
- Glomerular bleeding
- Pyelonephritis
- Kidney stones
- Mass lesions
- Recent instrumentation
- Trauma
- Exercise-induced hematuria
Imaging
- CT abdomen/pelvis without and with IV contrast for unexplained hematuria, especially with high malignancy risk
- Cystoscopy for bladder evaluation (gold standard for diagnosing bladder cancer)
Nephrolithiasis (Kidney Stones)
Presentation
- Renal colic/flank pain
- Hematuria (gross or microscopic)
- Nausea/vomiting
- Dysuria and urinary urgency
Diagnosis
- Low-radiation CT abdomen/pelvis without contrast: Preferred imaging for adults 3
- Ultrasound of kidneys and bladder with abdominal radiography as second-line alternative
Management
- Stones <5mm: Conservative management (most pass spontaneously)
- Stones 5-10mm: Trial of tamsulosin for up to 4 weeks
- Stones >10mm: Refer to urology
- Pain management and hydration for all patients
- Strain urine to collect passed stones for analysis
Urinary Incontinence
Types
- Stress incontinence: Urine loss with increased intra-abdominal pressure (coughing, laughing)
- Urgency incontinence/Overactive bladder: Strong, sudden urge with small volume voids
- Mixed incontinence: Features of both stress and urgency
- Overflow incontinence: Due to detrusor muscle underactivity or obstruction
Risk Factors
- Obesity
- Vaginal parity
- Older age
- Family history
Management
- Urinalysis for all patients
- Urine culture if UTI or hematuria suspected
- Lifestyle modifications:
- Avoid alcohol and caffeine
- Pelvic floor exercises (Kegels) for stress and urgency incontinence
- Bladder training for urgency incontinence
- Topical vaginal estrogen for peri/postmenopausal women with vaginal atrophy
- Continence pessaries for stress incontinence
- Complete initial therapy for 6 weeks before considering referral
Acute Kidney Injury (AKI)
Diagnosis (KDIGO Criteria)
- Increase in serum creatinine by ≥0.3 mg/dL within 48 hours, OR
- Increase in serum creatinine to ≥1.5 times baseline within 7 days, OR
- Urine volume <0.5 mL/kg/hour for 6 hours 3
Staging
- Stage 1: Creatinine 1.5-1.9× baseline or ≥0.3 mg/dL increase; urine output <0.5 mL/kg/h for 6-12h
- Stage 2: Creatinine 2.0-2.9× baseline; urine output <0.5 mL/kg/h for ≥12h
- Stage 3: Creatinine 3.0× baseline or ≥4.0 mg/dL; urine output <0.3 mL/kg/h for ≥24h or anuria for ≥12h
Management
- Only Stage 1 AKI with known etiology can be managed outpatient
- Refer to ER for:
- Stage 2 or 3 AKI
- Unclear etiology
- Sepsis concerns
- Significant comorbidities
- Discontinue nephrotoxic medications (NSAIDs, ACE inhibitors)
- Treat hypovolemia or hypervolemia
- Correct electrolyte imbalances
- Nephrology referral for co-management
Rhabdomyolysis
Presentation
- Classic presentation (ICK DUMP):
- Increased Creatinine Kinase
- Dark Urine
- Muscle Pain
- CK levels typically at least 5× upper limit of normal (1,500-100,000+ IU/L) 4
50% of patients don't report muscular symptoms 4
Causes
- Traumatic/muscle compression injury
- Non-traumatic exertional (extreme exercise)
- Non-traumatic non-exertional (medications, infections, electrolyte disorders)
Management
- Hospital admission for close monitoring
- Volume expansion with IV fluids
- Monitor for hyperkalemia and hypocalcemia
- Early renal replacement therapy may improve outcomes 5
- Nephrology consultation
Common Pitfalls to Avoid
- Overdiagnosis: Treating asymptomatic bacteriuria (except in pregnancy) 1
- Inadequate specimen collection: Contaminated specimens lead to false positives
- Delayed processing: Process urine specimens promptly or refrigerate
- Relying solely on urinalysis: Integrate clinical symptoms with laboratory findings
- Overlooking hematuria: Always follow up persistent hematuria after UTI treatment
- Delaying referral: Promptly refer patients with AKI beyond Stage 1 to emergency care
Remember that diagnosis should integrate clinical symptoms with laboratory findings, and treatment decisions should be based on the specific clinical scenario and patient characteristics.