Testicular Infarction

Testicular infarction is ischaemic necrosis of testicular tissue caused by interruption of its blood supply. Global infarction needs a major compromise of inflow or outflow.

The testis receives blood from the testicular artery (from the aorta), the cremasteric artery, and the artery of the vas deferens. Venous drainage is through the pampiniform plexus.

Causes:

• testicular torsion, the most common cause, with irreversible necrosis after 6 to 12 hours of complete torsion, and 24 hours for a 360-degree twist
• strangulation of the spermatic cord from incarcerated inguinal hernia
• epididymo orchitis with venous congestion and compartment syndrome (swollen epididymis compressing the cord vessels)
• trauma (blunt rupture and haematocele, cord injury)
• iatrogenic injury (inguinal hernia repair, hydrocele repair, orchidopexy, varicocelectomy with ligation of testicular artery, vasectomy, and scrotal surgery)
• thrombosis (hypercoagulable states, sickle cell disease, polycythaemia, vasculitis such as polyarteritis nodosa and Henoch-Schonlein purpura)
• venous infarction (pampiniform plexus thrombosis)
• severe infection
• mumps orchitis

Segmental testicular infarction (partial infarction of a segment) can be seen in children and adults without torsion. Causes are idiopathic, vasculitic, or epididymitis related. It has a wedge shaped appearance that can mimic a tumour.

Outcomes: atrophy, loss of testis, subfertility, hypogonadism (bilateral), and chronic pain.

• Acute torsion with infarction: sudden severe unilateral scrotal pain, nausea and vomiting, a high riding, horizontally lying, tender testis with absent cremasteric reflex, scrotal swelling and erythema (late), and negative Prehn sign.
• Later stages (days after infarction): the pain subsides, the testis becomes firm, enlarged and swollen, with a hydrocele, scrotal wall oedema and erythema, resembling epididymo orchitis, and finally atrophy over weeks.
• Segmental infarction: acute or subacute testicular pain, often without torsion, in young men with swelling.
• Fever, scrotal oedema and a firm tender testis with infection, abscess, or gangrene.
• Following surgery: a firm, painful, swollen testis in the days following hernia or varicocele surgery.
• Chronic infarction: a small, firm and atrophic testis.

• Clinical diagnosis in acute torsion, so that surgery is not delayed by imaging.
• Scrotal colour Doppler ultrasound shows:
  • absence or reduced intratesticular blood flow
  • an enlarged heterogeneous testis (hypoechoic initially, then heterogeneous with hyperechoic areas in haemorrhagic infarction)
  • twisting of the spermatic cord (whirlpool sign)
  • reactive hydrocele and scrotal wall thickening
  In segmental infarction, there is a well defined, wedge shaped avascular hypoechoic area, with preserved blood flow in the remaining testis. Contrast enhanced ultrasound shows no enhancement of the infarcted area.
• MRI: absence of enhancement of the infarcted area, T2 hypointense (haemorrhage) rim; useful to differentiate from tumour.
• Tumour markers (alpha fetoprotein, beta-hCG, lactate dehydrogenase) when a mass is seen, to exclude a germ cell tumour.
• Laboratory: complete blood count, C-reactive protein, urinalysis, thrombophilia or sickle cell testing, and autoimmune tests where indicated.

• Testicular torsion (suspected): emergency surgical exploration without delay, without waiting for imaging. Explore within 6 hours of onset of pain for best salvage. Salvage is about 90 to 100 percent within 6 hours, 50 percent within 12 hours, and under 10 percent after 24 hours.
• Manual detorsion may be tried as a temporising measure, but surgery is still mandatory. Usually rotate the testis outward in 'open book' fashion, turning the right testis anticlockwise and the left clockwise, up to 360 degrees, with analgesia.
• At surgery: detorsion, then warm saline soaked gauze for 10 to 15 minutes to assess viability (return of colour and bleeding at incision of the tunica). Perform orchidopexy with 3 to 4 non-absorbable sutures at 3 sites. Perform orchidopexy of the contralateral testis in the same operation.
• Orchiectomy for a necrotic, non-viable testis (black, no bleeding after warming and incision of the tunica albuginea). A necrotic testis left in place can lead to infection, pain and anti-sperm antibodies.
• Other causes: treat the underlying cause.
  • Incarcerated hernia: urgent reduction or repair.
  • Epididymo orchitis with compartment effect: antibiotics (ceftriaxone 500 mg intramuscularly single dose plus doxycycline 100 mg twice daily for 10 to 14 days in men under 35 with sexually transmitted infection risk; ofloxacin 200 mg twice daily or levofloxacin 500 mg daily for 10 to 14 days in older men), with scrotal elevation and analgesia. Surgery (epididymectomy, scrotal exploration with incision of the tunica albuginea for decompression) for suspected compartment syndrome.
  • Vasculitis: corticosteroid (prednisolone 1 mg/kg daily) and immunosuppression.
  • Sickle cell disease: hydration, analgesia and exchange transfusion in severe cases.
• Segmental infarction: conservative management, with analgesia (non-steroidal anti-inflammatory drugs, paracetamol), scrotal support, and ultrasound follow up at 4 to 6 weeks and 3 months.
• If the diagnosis of tumour is uncertain (an avascular lesion that does not shrink) or tumour markers are raised, perform surgical exploration with frozen section. Perform radical inguinal orchiectomy if cancer is confirmed. Testis sparing surgery with enucleation can be done if benign on frozen section.
• Infected infarcted testis (abscess, gangrene, pyocele): drainage, orchiectomy and antibiotics (piperacillin tazobactam 4.5 g every 6 to 8 hours or ceftriaxone with metronidazole).
• Postoperative care: scrotal support, analgesia, and avoiding strenuous activity for 2 to 4 weeks.
• Follow up: ultrasound at 3 to 6 months for atrophy; semen analysis at 3 to 6 months; testosterone, LH and FSH if bilateral or if only one testis remains.
• Counsel about fertility, reduced in about 20 to 30 percent even after detorsion and orchidopexy because of anti-sperm antibodies and atrophy.
• Consider a testicular prosthesis (silicone, 6 months after healing) for cosmesis after orchiectomy.
• Prevention: counsel boys and parents to seek urgent care for acute scrotal pain; educate about the "6-hour window."