In an adult (20‑50 year‑old) male from a TB‑endemic region, what are the typical clinical signs, symptoms, and urinalysis findings of genitourinary tuberculosis?

Genitourinary Tuberculosis: Clinical Presentation and Urinalysis Findings

In adult males from TB-endemic regions, genitourinary tuberculosis typically presents with non-specific irritative voiding symptoms (frequency, dysuria), hematuria, and sterile pyuria—the hallmark urinalysis finding is pyuria with hematuria in the absence of bacterial growth on routine culture. 1, 2

Clinical Signs and Symptoms

Most Common Presentations

• Irritative voiding symptoms occur in more than 50% of patients, including increased urinary frequency, urgency, and dysuria 3
• Hematuria is extremely common and often accompanies pyuria 1, 2
• Loin pain (flank or lumbar pain) is the most frequent symptom, present in approximately 27% of patients 4
• Abdominal and suprapubic pain are frequently reported 1
• Difficulty voiding or obstructive symptoms may develop as disease progresses 1

Constitutional Symptoms

• Constitutional symptoms are less frequent than local urinary symptoms, which is a critical diagnostic pitfall—patients may not appear systemically ill 2
• Fever, weight loss, and night sweats occur but are not the predominant presentation in genitourinary TB 2

Key Diagnostic Pitfall

• Only 23.5% of patients have a known history of pulmonary tuberculosis, so the absence of prior TB does not exclude the diagnosis 2
• The disease is almost always secondary to hematogenous spread from chronic latent TB infection, not direct extension 1

Urinalysis Findings

Pathognomonic Pattern

• Sterile pyuria with hematuria is the classic urinalysis finding—pyuria plus hematuria with negative routine bacterial cultures 2, 5
• This "sterile pyuria" occurs because Mycobacterium tuberculosis does not grow on standard bacterial culture media 5

Specific Urinalysis Characteristics

• Pyuria (white blood cells in urine) is present in the majority of cases 2, 5
• Hematuria (microscopic or gross) accompanies the pyuria 2, 5
• Negative routine urine cultures despite significant pyuria—this is the key that should trigger suspicion for TB 2, 5
• Acidic urine pH is typical (though not always documented in guidelines) 5

Diagnostic Approach

High Index of Suspicion Required

• Diagnosis relies on high clinical suspicion based on patient history and risk factors, as there is no single diagnostic test 1
• Risk factors include: diabetes, advanced age, low BMI, immunosuppression (HIV), renal failure, and poor socioeconomic conditions 1

Essential Diagnostic Tests

• Collect multiple early-morning urine samples (at least 3-6 specimens) for acid-fast bacilli (AFB) staining and mycobacterial culture, as Ziehl-Neelsen staining is positive in only 48% of cases 2
• Mycobacterial urine cultures take a mean of 2.3 weeks to become positive, so empiric treatment may be needed while awaiting results 2
• Newer rapid tests including radiometric liquid culture systems (BACTEC) and PCR provide faster results with higher sensitivity 3

Imaging Studies

• Intravenous urography (IVU) is abnormal in 95% of cases and provides both anatomical and functional kidney assessment 2
• Common IVU findings include: non-visualized kidney (23%), hydronephrosis/hydroureteronephrosis (31%), calyceal distortion/cavitation/scarring (14.5%), and contracted "thimble" bladder 4
• MRI can be used in patients with renal failure when contrast studies are contraindicated 3

Microbiological and Molecular Testing

• Demonstration of Mycobacterium tuberculosis in urine or body fluid is the gold standard 3
• Histological examination of tissue (if biopsy performed) may show caseating granulomas 1

Critical Clinical Pearls

Presentation Patterns

• Patients are most commonly 30-69 years of age, with a mean age around 48-51 years 2
• Male-to-female ratio is approximately 1.4:1 4
• The disease can remain asymptomatic for extended periods, leading to late presentation with advanced disease 4

Common Pitfalls to Avoid

• Do not dismiss recurrent "sterile" UTIs—relapsing urinary infection with sterile pyuria over months to years is a red flag for genitourinary TB 5
• Slow progression causes continuous renal parenchymal destruction, so early diagnosis is critical to prevent irreversible damage 4
• Sequelae develop in 42% of cases if diagnosis is delayed, including non-functioning kidneys, ureteral strictures, and bladder contracture 2

Treatment Implications

• Combination drug therapy is first-line treatment: 2 months of isoniazid, rifampicin, pyrazinamide, and ethambutol, followed by 4 months of isoniazid and rifampicin 1
• If identified early and treated appropriately, GUTB is curable; delayed diagnosis leads to nephrectomy (19% of cases) or reconstructive procedures 4