Causes of Penile Edema

Infectious Causes

Gonococcal and chlamydial infections are the most common infectious causes in sexually active men under 35 years, often presenting with associated urethritis and penile edema 1, 2
Chlamydia trachomatis and Neisseria gonorrhoeae are the predominant organisms in men under 35 years 1
Enteric organisms cause epididymitis in older men or those with urinary tract abnormalities 2
In immunosuppressed patients, fungi and mycobacteria become more likely causative organisms 1

Fournier gangrene involves the scrotum and penis with insidious or explosive onset, mean age 50 years, most commonly in diabetic patients 3
Mixed aerobic and anaerobic flora including staphylococci and Pseudomonas species cause most cases of Fournier gangrene 3
The infection extends along fascial planes from perianal, retroperitoneal, or urinary tract sources 3

Deep venous thrombosis can cause secondary genital edema through venous congestion 2
Phimosis can contribute to penile edema through impaired lymphatic drainage 4
Post-surgical complications following hydrocelectomy may present with persistent swelling 5

Ultrasound with Doppler is the first-line imaging modality to distinguish between etiologies, assess testicular perfusion, and identify complications 2, 5
Both grayscale and color Doppler must be performed to evaluate for abscess, hematoma, fluid reaccumulation, or underlying testicular mass 5
Failure to improve within 3 days requires reevaluation of diagnosis and therapy 2, 5
Delay beyond 6-8 hours in torsion-related cases significantly increases risk of testicular loss 2
Systemic signs including fever, tachycardia, and diaphoresis suggest necrotizing infection requiring immediate surgical consultation 3

False-negative Doppler evaluations can occur in partial torsion or spontaneous detorsion 2
Hydroceles can mask testicular cancer, leading to delayed presentation of metastatic disease 5
Early presentation may not show classic symptoms of serious underlying pathology 2
Penile fracture and pelvic fractures can cause secondary penile edema 4