Our patient was a 63-year-old retired gentleman, weighing 64 kilograms and 1.8 meters tall. He had no significant family history and drank only occasionally. At presentation he was trying to give up a 40 pack-year smoking habit. His medications were predominately analgesics but also a bisphosphonate and prednisolone 20 mg.\nHe had a history of SLE, haemolytic anaemia, recurrent idiopathic thrombocytopenia purpura and recent chemotherapy (6 months previously) for diffuse large B-cell lymphoma.\nHe presented to clinic with a tender, diffusely enlarged right testicle, and was also noted to be suffering from night sweats, a 7 kg weight loss, and splenomegaly (previously noted prior to treatment for lymphoma).\nTumour markers were normal, but an ultrasound scan of his right testicle showed a non-homogenous abnormality inferiorly (), in keeping with a recurrence of lymphoma or a primary malignancy [].\nGiven his history and symptoms, he was urgently referred to the urologists who decided to proceed with a right orchidectomy.\nHistology of the right testis showed a granulomatous orchiditis. A Ziehl-Neelson (ZN) stain showed a large number of acid fast bacilli (AFB) which, given the morphology and absence of caseation, was most consistent with a NTM infection. Unfortunately, no sample had been sent for culture, but given the histological findings and clinical presentation, this was considered most likely to be Mycobacterium avium-intracellulare (MAI) infection.\nHe recovered well post operatively, and, as a CT scan showed a right apical lung lesion, he was referred to the local respiratory physician for further investigation and management.\nBronchial washings of the right upper zone and left lingula were positive for AFB. He was commenced on conventional quadruple anti-tuberculous therapy pending formal identification of the AFB. The organism was subsequently confirmed as MAI, and therapy was switched according to the British Thoracic Society guidelines [].
A 33-year-old man presented with right scrotal hardening and swelling, accompanied by inguinal pain and flank soreness, for 3 months. An off and on fever was also noted. Right epididymitis was the initial impression, and oral antibiotics of Cephalexin were prescribed. The symptoms persisted after treatment. An ultrasound examination showed heterogeneous echogenicity of the right testis, suggesting a testicular tumor. A further pelvic computed tomographic scan revealed enlargement of the right testis estimated to be 4.5 x 4.0 cm in dimension, with heterogeneous enhancement, suspected of being a testicular tumor (Fig. ). No abdominal lymphadenopathy was found. Serum tumor markers, including α-fetoprotein, β-human chorionic gonadotropin (β-hCG) and lactate dehydrogenase (LDH), were within normal limits. A right radical orchiectomy was performed under the impression of a testicular tumor.\nOn gross examination, the testis revealed an ill-defined, gray to tan, soft-tumor-like lesion measuring 3.3 x 3.2 x 2.6 cm (Fig. , ). Histologically, the lesion disclosed dense lymphoplasma cell and histiocyte infiltration in the interstitium, as well as spindle cell proliferation (Fig. , , ). There were small foci of foamy histiocyte aggregation and microabscess formation in the lesion (Fig. ). Some of the blood vessels revealed obliterative vasculitis (Fig. ). The seminiferous tubules revealed atrophic change (Fig. ). There was no well-formed granuloma or caseous necrosis in the lesion. The inflammatory process had also partially affected the epididymis and spermatic cord.\nA panel of histochemical stains and immunohistochemical (IHC) stains was performed. IHC staining of CD68 (1:250; Biocare) and CD163 (1:50; Leica) proved a histiocytic nature. The spindle cells were focally positive for smooth muscle actin (1:50; DAKO), but negative for ALK (1:200; NOVO) and CD21 (1:100; Cell Marque), suggesting a myofibroblastic origin. No significant immunoglobulin G4 -positive plasma cell infiltration was seen (IgG4, 1:800; Invitrogen). No microorganisms were demonstrated by acid-fast, periodic acid-Schiff, Grocott-Gomori methenamine-silver stains, or Gram’s stain. IHC with a rabbit polyclonal antibody against Treponema pallidum (dilution 1:100, Biocare Medical, Concord, CA, USA) displayed some spirochetes in the cytoplasm of histiocytes (Fig. ), highly suggestive of syphilitic orchitis.\nPolymerase chain reaction (PCR) testing for the T. pallidum DNA polymerase I gene using paraffin-embedded tissue was done. Positive control was applied using an anal biopsy specimen previously diagnosed as syphilis proved by immunohistochemistry and serology. A semi-nested PCR using the primers of TPmod-F1 (5′-GTGTGCACTGGGCATTACAG-3′), TPmod-F2 (5′-TGAAGCTGACGACCTCATTG-3′), and TP mod-R1 (5′- GTCTGAGCACTTGCACCGTA-3′) targeted a different region of the T. pallidum DNA polymerase I gene (Fig. ) []. Direct sequencing proved positivity for T. pallidum, which confirmed the diagnosis of syphilitic orchitis.\nThe patient underwent further serology tests postoperatively. An anti-human immunodeficient virus (HIV) enzyme-linked immunosorbent assay (ELISA) and Western blot tests were positive. However, serology tests for syphilis, including both Venereal Disease Research Laboratory (VDRL) test and Treponema pallidum particle agglutination (TPPA), demonstrated false-negative results. At that time, the patient had a low CD4 count (72 cells/mm3) and a low CD4/CD8 ratio (0.07).