A 48-year-old man from Argentina with no personal history of interest with progressive enlargement and pain in the left testicle of 2 months' evolution; no urinary symptoms, no fever. He was treated with various antibiotics without improvement.
Physical examination revealed a hard tumour on the left testicle that was painless and without signs of fluctuation. Complementary tests: Haemogram: Lymphocytosis, the rest normal. Urine sediment: pyuria. Urine culture: sterile. Semen cultures: E. coli (1st), S. Sprophiticus (2nd), P. Mirabilis (3rd). Tumour markers: CEA, alpha foetus and BHCG normal. Urinary ultrasound: normal. Testicular ultrasound: Heterogeneous left testicular tumour without liquid areas inside. Positive Mantoux test with ulceration. In the absence of clinical and radiological improvement, radical orchiectomy was performed and the pathological study reported non-specific orchitis.

A sample was sent to microbiology, consisting of purulent exudate obtained intraoperatively from the testicular tissue. Auramine staining for mycobacteria was negative. Gram staining showed polymorphonuclear leukocytes and few Gram(+) bacilli, some of them filamentous, with irregular staining and with bulging bacillary ends in the form of maces. Genomic amplification (PCR) for M.tuberculosis was negative. Chlamydia antigen detection was also negative. Culture for usual bacteria, including Neiseria and Haemophilus, were negative at 72 hours of incubation.
At 96 hours, growth was detected in the culture of a micro-organism very adherent to the medium, difficult to emulsify, which on Gram staining showed a Gram(+) bacillus morphology of coryneform appearance, sometimes with irregular staining and some with club-shaped terminations.
Phenotypic identification did not provide significant data, so genetic study by 16SrRNA sequencing was performed and the strain was identified as Corynebacterium thomsseni. Cultures for Nocardia, mycobacteria and fungi were negative. The isolated strain was highly sensitive to Penicillin, Ampicillin, Amoxicillin with clavulanic acid, Cefotaxime, Gentamicin, Amikacin, Erythromycin, Tetracycline, Trimethoprim sullfamethoxazole, Rifampicin and Imipenem.