Patient's question:

Fungus, Epididymitis

Doctor's answer:

Hello,
1. Acute Epididymitis
Epididymitis has three common causes:
① Secondary to prostatitis or urinary tract infection.
② Prostatectomy, especially transurethral surgery, because bacteria may remain in the urine for 8–12 weeks postoperatively. During urination, urine may reflux into the vas deferens, causing retrograde infection and leading to epididymitis; infection can also spread to the epididymis via surrounding lymphatic vessels.
③ Chemical epididymitis caused by sterile urine refluxing into the vas deferens. Recent studies have found that urine can reflux into the seminal vesicles.
Pathophysiology and Early Pathology
Acute epididymitis is initially a cellulitis that starts in the vas deferens and spreads to the tail of the epididymis. During the acute phase, the epididymis swells and becomes hard, with infection spreading from the tail to the head. On histopathological examination, small abscesses can be seen, and the tunica vaginalis often secretes serous fluid (inflammatory hydrocele). This fluid may contain pus, the spermatic cord may thicken, and the testis may become secondarily congested and swollen, though inflammation is generally absent. Under light microscopy, tissue edema, neutrophil, plasma cell, and lymphocyte infiltration can be observed, followed by abscess formation. Epithelial necrosis may occur, and inflammation can be completely absorbed. However, fibrosis around the epididymal tubules often leads to lumen obstruction, which may result in infertility if bilateral epididymitis is present.
Clinical Manifestations
1. Symptoms
Epididymitis often occurs after heavy physical labor, such as lifting heavy objects, or after intense sexual arousal. Trauma caused by urethral instrumentation can also lead to epididymitis, and it may develop post-prostatectomy. Epididymitis is often secondary to prostatitis. Pain in the scrotum typically occurs suddenly and may radiate along the spermatic cord to the inguinal region and lumbar-sacral area. The pain is usually severe, with marked tenderness and rapid swelling, which can double the size of the epididymis within 3–4 hours. The temperature may rise to around 40°C, and purulent discharge may appear in the urethra, often accompanied by cystitis and cloudy urine.
2. Signs
Tenderness is present in the inguinal region, the scrotum is enlarged, and the skin is red and swollen. If an abscess forms, the skin may become dry, thin, and easily peeling. Abscesses may also rupture spontaneously. If diagnosed promptly, the swollen and hardened epididymis can be distinguished from the testis. However, within hours, the testis and epididymis may merge into a hard mass. The spermatic cord may thicken due to edema, and secondary hydrocele of the tunica vaginalis may develop within a few days. Purulent discharge may be present in the urethra. Prostate palpation may reveal acute or chronic prostatitis, but digital massage should be avoided during the acute phase.
3. Laboratory Tests
Peripheral blood leukocyte count may reach (2–3) × 10?/L. Urethral discharge can be examined via staining or non-staining methods. Urinalysis is also an important diagnostic tool.
4. Ultrasound
Ultrasound can visualize the swelling and inflammatory extent of the epididymis and testis.
5. MRI
Epididymitis is diffuse or focal. On T2-weighted images, the signal from the epididymis may be the same as or higher than that of the testis.
(IV) Differential Diagnosis
1. Tuberculous Epididymitis
Pain is rare, and the epididymis and testis are clearly demarcated on palpation. The vas deferens appears beaded, the surface of the prostate is uneven, both seminal vesicles are thickened, and "sterile" urine is observed on smears. Mycobacterium tuberculosis can be cultured.
2. Testicular Tumor
The mass is painless. If acute hemorrhage occurs within the tumor, sudden increases in pressure may cause testicular and epididymal pain. The testicular mass can be distinguished from the normal epididymis. Prostate examination and urinalysis are normal. If doubt remains, human chorionic gonadotropin (hCG) testing may be performed, as approximately 15% of testicular tumors are positive. If the diagnosis is uncertain, intraoperative rapid pathology may be performed to determine whether orchiectomy is necessary.
3. Testicular Torsion
Common in prepubertal children and rarely in adults. Epididymitis is more common in older age groups. In early testicular torsion, the epididymis is palpable in front of the testis, and the testis is retracted superiorly. Later, the epididymis and testis form a painful, enlarged mass. Prehn’s sign helps differentiate the two: if pain decreases when the scrotum is lifted to the pubic symphysis, it is likely epididymitis; if pain worsens, it is likely testicular torsion. If torsion cannot be ruled out, surgical exploration is necessary.
4. Testicular or Epididymal Appendage Torsion
A rare condition in prepubertal boys. These pedunculated structures can wrap around, causing localized pain and swelling. In early stages, a hard nodule can be palpated at the superior pole of the testis, while the epididymis appears normal. In later stages, the entire testis is swollen, making differentiation from epididymitis, testicular torsion, or appendage torsion difficult. Since testicular torsion requires prompt treatment, active surgical exploration should be performed in this case.
5. Testicular Injury
May cause acute epididymitis but can be differentiated by trauma history and the absence of purulent urine.
6. Mumps-Associated Orchitis
Typically occurs with mumps and often lacks urinary symptoms. Urinalysis shows no pus cells or bacteria.
(V) Complications
Abscesses are rare but may develop after urethral instrumentation or digital massage. Abscesses may drain spontaneously into the scrotum or require surgical drainage. Epididymal abscesses may extend and damage the testis (epididymo-orchitis), though this is uncommon.
(VI) Prevention
Prostatitis and urinary tract infections should be treated thoroughly. If recurrent acute epididymitis occurs, bilateral vasectomy may be performed to prevent recurrence.
(VII) Treatment
1. Specific Treatment
If the patient visits within 24 hours of onset, infiltration anesthesia of the spermatic cord above the testis with 20 mL of 1% procaine or lidocaine may completely relieve the condition. Body temperature typically falls rapidly, pain disappears, and inflammatory masses may resolve within days. If one injection is insufficient, a second may be administered the next day. Antibiotics are helpful and can quickly treat secondary cystitis. Antibiotic selection should be based on bacterial culture and sensitivity tests. Commonly used drugs include sulfamethoxazole-trimethoprim, ciprofloxacin, ofloxacin, and third-generation quinolones or cephalosporins, all of which are effective.
2. General Treatment
During the acute phase (3–4 days), bed rest is recommended. A scrotal support can alleviate symptoms, and a homemade scrotal support with cotton padding is more comfortable. Painful patients may take analgesics, and local heat therapy can relieve symptoms and promote inflammation resolution. However, early heat application may worsen pain and risk spreading infection, so ice packs are preferred in the early stages. Sexual activity and physical labor may exacerbate infection, so they should be avoided.
(VIII) Prognosis
Acute epididymitis responds well to treatment, with symptoms gradually resolving within 1–2 weeks. However, it may take 4 weeks or longer for the epididymis to return to normal size and texture. Complications are uncommon, but bilateral epididymitis may lead to infertility.