A 26-year-old man presented to uroligy clinicians with right testicular pain and a right epididymal mass. It was a challenge to diagnose the cause—until he revealed some essential clues.
The differential diagnosis included testicular malignancy and lymphoma. However, tumor markers were within normal limits. Tests for HIV and syphilis were negative. The clinicians also considered granulomatous or chronic orchitis, but after treatment with nonsteroidal anti-inflammatory drugs, the pain and palpable epididymal mass had resolved. Then, follow-up testicular ultrasound images showed new diffuse heterogeneous hypoechoic lesions in the right testis.
The patient elected to have a right radical orchiectomy with sperm cryopreserved. He recovered well, and semen analysis did not show any abnormalities.
Pathology of the surgical specimen revealed necrotizing and nonnecrotizing granulomas. At this point, the patient recollected that he had developed cervical lymphadenopathy and oral ulcers several weeks after traveling to South America, 8 months before presenting with the testicular symptoms.
Combined with another clue—frequent exposure to cats during his South America trip—the patient’s symptoms now created a clearer picture. He had been diagnosed with toxoplasmosis at the time but had not received treatment because he was immunocompetent. The patient’s symptoms had resolved spontaneously, and he said he had been in his usual health between then and when he developed the testicular pain.
Based on this new information, the clinicians conducted immunohistochemical tests, which revealed isolated cysts about 20 µm in diameter, confirming a diagnosis of testicular toxoplasmosis. They started him on systemic toxoplasmosis treatment; he has been in good health since.
The clinicians note that toxoplasmosis is highly prevalent, infecting up to 30% of the world’s population. Cat feces is one source of infection with Toxoplasma gondii, which is typically asymptomatic. In immunocompetent patients, it tends to present as an acute infection that is benign and self-limited.
Only a few cases of testicular toxoplasmosis have been reported in the literature, and all have been in immunocompromised patients. Because this patient was immunocompetent, the case is unique, being the only one reported as yet. Given the immunocompetence, the clinicians say, the patient demonstrates the need for clinicians to have a high index of suspicion.
Wong V, Amarasekera C, Kundu S. BMJ Case Rep. 2018;2018. pii: bcr-2018-224962.