Acute scrotal pain with a twist

Abstract

Intratesticular lesions identified on ultrasound are usually malignant. It presents a particular dilemma to the surgeon when conservative approach is considered. A 55-year-old smoker with peripheral vascular disease had attended the accident and emergency with acute left hemiscrotal pain of 24-h duration. Clinical examination revealed a swollen, tender hemiscrotum. Ultrasound had demonstrated a hypo-echoic lesion in the testis measuring 2 × 1.8 cm. This was reported as possible infarct and managed conservatively. On review after 4 weeks, the patient was still symptomatic with persistent dull pain. A repeat scan in 4 weeks showed persistence of the lesion raising the possibility of tumour. Tumour marker profile was not elevated. The patient had a radical orchidectomy and the histology showed segmental infarction of the testis with thrombosis of the segmental testicular vessels. Peripheral vascular disease can cause segmental infarction of the testis due to the end arterial blood supply; in these cases, magnetic resonance scan can be diagnostic. Once confirmed, segmental infarcts can be safely managed conservatively.

Segmental testicular infarction is uncommon. Less than 40 cases have been reported in the literature.¹ Most cases appear to be idiopathic or due to haematological disorders like sickle cell or vasculitis.^2–6 Infective or severe inflammatory process can also lead to infarction.⁷ It commonly occurs between the second and fourth decade of life.⁸

It is difficult to distinguish between an infarct and a testicular tumour especially if the tumour is small in size.⁹ Therefore, orchidectomy tends to be performed and the diagnosis made on histology. A conservative approach is possible if the diagnosis is reached with a high degree of certainty.^3,4

Case history

A 55-year-old man attended the accident and emergency department with a 24-h history of acute left hemiscrotal pain that had no precipitating factors and was not accompanied by any urinary symptoms. He was a known hypertensive, heavy smoker and an arteriopath. As a result of the latter, he had a left common iliac angioplasty and subsequent stent insertion in 2000. Clinically, the testis was found to be normally positioned, mildly tender with some fluid in the tunica vaginalis but normal scrotal skin. His urine dipstick was negative. An urgent ultrasound of testes was obtained which showed an abnormal hypodense area (size 2.0 × 1.8 cm) in the centre of the left testis extending to the surface. Although the appearance was considered non-specific, the possibility of testicular ischemia or infarction was raised (Fig. 1). He was managed conservatively as his acute symptoms had settled. He was reviewed a month later when he was still symptomatic with persistence of dull testicular pain. A repeat ultrasound scan confirmed the persistence of the hypo-echoic lesion, thus raising the suspicion of the lesion being a tumour. However, tumour markers were normal. A staging computed tomography (CT) scan did not reveal any retroperitoneal, pelvic or inguinal lymphadenopathy. There was no sign of metastatic spread although there were soft tissue densities in both lungs suggestive of non-calcified granuloma. Due to the suspicion of neoplasia and persistence of symptoms, a choice of watchful wait with repeat ultrasound scan in 3 months versus immediate surgery was offered to the patient. Given these options and the relevant information, the patient opted for a radical orchidectomy.

Figure 1.

Ultrasound of testes showing an abnormal hypodense area.

Pathological findings

Macroscopically, the testis weighed 48 g and measured 70 × 35 × 25 mm. There was a central area of haemorrhage and necrosis. The rest of the testis appeared within normal limits.

Microscopically, sections showed a central area of wedge-shaped, partly haemorrhagic infarction with ghosts of seminiferous tubules and an outer rim of atrophic tubules. Two large thrombosed vessels were identified adjacent to the infarcted area (Fig. 2). The interstitium showed mild chronic inflammation and many haemosiderin laden macrophages consistent with reaction to haemorrhage. Elsewhere, the testis showed normal spermatogenesis with maturation as well as an occasional Sertoli cell nodule. The spermatic cord and rete testis were unremarkable.

Figure 2.

Thrombosed vessel with infarct on the left and atrophic area on the right.

Discussion

This case highlights some important points in the diagnosis and management of segmental infarction. The history of peripheral vascular disease was significant in this case. He had developed significant stenosis (75%) of his left common iliac requiring angioplasty and, subsequently, a stent after the atheroma recurred.

The testicular artery, a branch of the aorta, traverses through the spermatic cord. It gives off a branch to the epididymis and then reaches the back of the testis. Here, it divides into medial and lateral branches that sweep around horizontally within the tunica albugenia. Branches from these vessels penetrate the substance of the testis forming the segmental end vessels.¹⁰ Due to this, the testis is exposed to the risk of end arteritis and segmental infarction.

Ultrasound is the initial imaging method of choice in diagnosis and has a > 95% sensitivity and specificity in identifying the intratesticular lesions.^11,12 Most intratesticular lesions are malignant. Colour Doppler ultrasound can be difficult to detect increased blood flow in tumours less than 2 cm in size and presence of hyper vascularity is not specific for a diagnosis of malignancy. A solid hypo-echoic mass in the testis should be considered malignant until proven otherwise.¹¹ Segmental infarcts are hypo-echoic as well.^3,4 Segmental testicular infarction ultrasound features are not always wedge-shaped but have reduced or absent vascularity.¹³ In a case that confounds the diagnosis, an magnetic resonance scan with contrast would show an infarcted area with an enhanced rim.¹ In these cases, a combination of ultrasound and magnetic resonance as imaging modalities can be helpful in arriving at the diagnosis,^14,15 and this will aid in further follow-up with ultrasound scans to assess complete regression or static nature of the lesion.^3,4 Ultrasound scan with contrast is a new modality in use but its efficacy is still to be proved.

Once diagnosed correctly, segmental testicular infarction can be managed conservatively avoiding loss of testis. Although it could be argued that, in the absence of abnormal tumour markers, a tumour is less likely, it has been shown that tumours can still be present in spite of a normal tumour marker level.¹⁶ As there is an element of uncertainty with this type of presentation, patients should be offered the relevant information to make an informed decision in the final treatment choice. This becomes particularly important in patients with solitary testis and or sub-fertility status where additional imaging modalities as discussed above should be considered to help the patient make his decision.