Epididymoorchitis due to Mycobacterium marinum – the first case description Petr Macek1, Monika Bodnárová2, Jakub Závada3, Petr Ježek4, Ivo Pavlík5, Marta Havelková6, Jaroslava Dušková7 1) Department of Urology, General University Hospital and 1st Faculty of Medicine Charles University Prague, Czech Republic 2) Department of Dermatovenerology, General University Hospital and 1st Faculty of Medicine Charles University Prague, Czech Republic 3) Institute of Rheumatology, Prague, Czech Republic 4) Department of Clinical Microbiology and Parasitology, County Hospital Přibram, Czech Republic 5) Veterinary Research Institute, Mycobacteriology Unit, O.I.E. Reference laboratories for paratuberculosis and avian tuberculosis, Brno, Czech Republic 6) National reference laboratory for mycobacteria, National Institute of Public Health, Prague, Czech Republic 7) Institute of Pathological Anatomy, General University Hospital and 1st Faculty of Medicine Charles University Prague, Czech Republic

Abstract Background Investigations Diagnosis Management

The Case Sixty year old male was referred to Department of Urology for 1 day history of unilateral scrotal tenderness with only a minimal swelling which occurred during patient’s hospital stay at the Institute of Rheumatology. On examination, there was very mild right-sided scrotal enlargement and some redness of the skin. The involved side of the scrotum was generally firmer, the testis and epididymis were only slightly tender on palpation and no fluctuation was felt. Patient denied general symptoms and his temperature was 37,1°C. He admitted mild urinary hesitancy and slower flow for few months already, however denied any actual burning or stinging or any acute worsening of urinary symptom. His urological history included similar right sided scrotal swelling 4 weeks ago for which he attended office urologist in his city and was treated with oral antibiotics (however was unable to not recall its name) for 1 week and tamsulosin 0,4 mg daily was commenced for his mild urinary symptoms. Following the antibiotic treatment patient’s local scrotal symptoms and swelling disappeared.

Personal history included appendectomy at the age of 10, no smoking and no history of alcohol abuse. His primary medical problem was 10 months history of gradually increasing swelling of metacarpophalangeal and interphalangeal joints of 2nd to 4th finger on his right hand. The swelling started after a small injury on the tip of the index finger when cleaning an aquarium. The site of injury was red and swollen, but there were no general symptoms. He was treated by repeated courses of antibiotic treatment by his local physician however with only minimal response. Over the time the primary site of injury healed up and swelling of metacarpophalangeal joint index finger occurred. Thereafter its size was slowly increasing for few months. Gradually, middle and ring finger became swollen and tender as well. Because of failed response to antibiotic course, working diagnosis of rheumatoid disease was determined by office rheumatologist in his city and course of methylprednisolone 16 mg daily was commenced. For the period of 2 weeks just prior to the admission there was also concomitant treatment with 10 mg of methotrexate daily and it was ceased due to lack of efficacy. Because of no response to the therapy was he admitted to the Institute of Rheumatology for further diagnostic work-up. At the Institute of Rheumatology swollen joint aspiration was performed, however all cultures from joint fluid and Gram stain were negative. Mantoux II test result was 10 mm. After 4 days of the hospital stay scrotal tenderness and swelling occurred. At the time of presentation to Department of Urology, the treatment with methylprednisolone was ongoing for 3 months. His medications were only methylprednisolone and tamsulosin. He denied diabetes, allergies and other medical problems. Patient was working as a grinder. He was also a breeder of many freshwater aquarium fish, of which some were deformed and anorexic at the time of patient’s injury.

Diagnosis Scrotal ultrasound revealed normal left testis and epididymis and significant enlargement of right epididymis and multiple hypoechoic foci within the testis with diffusely increased blood flow on Doppler mapping both in the testis and epididymis including the hypoechoic foci (Figure 1a,b). The ultrasound picture was highly suspicious of epididymoorchitis with multiple small abscesses, which was our working diagnosis. Urinalysis including sediment was completely negative. However there was a discrepancy between severe sonographic appearance of inflammatory process and relatively good overall condition of the patient and minimal local symptoms. Patient was admitted, the suprapubic tube was inserted as per institution protocol for the treatment of acute epididymitis and antibiotic treatment with ofloxacin 200 mg every 12 hours orally in combination with gentamicin 240 mg once daily was commenced. Laboratory results showed white cell count of 7,6 x 109/l and CRP 10,9 mg/l, all other tests including renal function, liver function tests were with normal range. Urine cultures returned negative, including those for Mycoplasma and

Ureaplasma. Urine PCR for Chlamydia and Neisseria gonorrhoeae was negative too. These results admitted the option of infection with Mycobacterium sp.. Patient however denied any previous family or personal history of any form of tuberculosis, was never treated with BCG vaccine, denied ingestion of unpasteurized milk and was monogamous heterosexual male with no history of intravenous drug use. The fact that patient mentioned a history of finger injury when cleaning an aquarium with sick fish brought up a possibility of rare infection with Mycobacterium marinum (MM). This mycobacterium belongs among opportunistic, photochromogenic, non-tuberculous (= atypical) slowly growing mycobacteria and is the most commonly affecting atypical mycobacterium in humans1-4. Skin and joints appearance together with no response to antibiotic treatment were very suggestive, because in otherwise healthy subjects these mycobacteria cause mainly granulomatous cutaneous lesions (so-called “fish-tank or swimming-pool granuloma”), tenosynovitis or osteomyelitis1, 5. Also 3 month history of immunosupression with methylprednisolone and 2 weeks of methotrexate for alleged rheumatoid disease was a contributing factor, because individuals immunocompromised due to various reasons (e.g. corticosteroids, post-transplantation, HIV infection) can develop a systemic disease which may be life-treatening2, 6-8. Only rare cases of systemic spread were reported in immunocompetent patients9. Dermatologist with the experience in treatment of atypical mycobacterioses was consulted and based on presence of hand oligoarthritis, forearm subcutaneous nodules and olecranon bursitis confirmed the suspicion. Three urine samples were sent for culture and microscopy, but local microbiologic laboratory started cultures only at 37°C. These cultures returned negative in 3 weeks, including microscopy. Urine PCR for Mycobacterium tuberculosis was also negative. Chest X-ray did not show any signs of active or past pulmonary tuberculosis, HIV testing was negative. Fluid aspiration from 2nd metacarpophalangeal joint was performed for the second time. This again grew no ordinary bacteria, but the sample was also sent to county laboratory with previous experience in cultures of atypical mycobacteria. Microscopy with Gram stain was negative, but microscopy with Ziehl-Neelsen stain and fluorescence with auramine stain revealed many acid-fast bacilli (AFB). Joint fluid PCR for Mycobacterium tuberculosis was negative. Cultures at Löwenstein-Jensen, Ogawa and Sula media at 30°C were started and also BACTEC MGIT 960 method for rapid identification. Temperatures within the range of 28°C to 33 °C should be used for the culture if MM infection is possible5, 6. PCR REA of joint fluid identified Mycobacterium marinum. PCR REA of the urine and ejaculate was negative. Treatment was then changed to a combination of ofloxacin 200 mg every 12 hours, clarithromycin 500 mg every 12 hours daily and ethambutol 2 g once daily. This was based on the previous empiric experience with the treatment of several patients with cutaneous MM infection5. MM is naturally multi-resistant, with common resistance to isoniazid, streptomycin and pyrazinamide and on the

other hand it is usually sensitive to rifampicin, ethambutol, clarithromycin, quinolones, doxycycline, minocycline or trimethoprim/sulfamethoxazole2, 3, 5, 6. Combination with 3 or more drugs is recommended for the treatment of systemic infections10. Suprapubic tube was removed because canalicular spread of infection from the urinary tract was unlikely. Patient was transferred back to the Institute of Rheumatology for further treatment due to severe arthritis on his right hand. Further diagnosis included QuantiFERON®-TB Gold test that was positive. Patients with MM infection can have positive result in up to 58 %11 and previously mentioned tuberculin skin test could also be positive after exposure to non-tuberculous mycobacteria12. Three-phase abdominal CT was normal. Magnetic resonance imaging of the right hand and bone scan revealed osteomyelitis of affected metacarpophalangeal joints.

Treatment and Management After 12 days of treatment with combination of ofloxacin, ethambutol and clarithromycin patient returned for follow-up urology check-up. Local scrotal condition did not change, but the ultrasound showed enlargement of hypoechoic areas with epididymis suggestive of the disease progression with abscess or necrosis formation. After discussing the options with the patients, scrotal orchiectomy was carried out next day without complications. The removed specimen was cut open and this revealed oval area (3 x 2 cm) filled with a transparent jelly-like matter in the body of epididymis and several pale irregular nodules in the head and tail of the epididymis, all suggestive of caseous inflammation. The testis was full of small whitish foci suggestive of miliary orchitis (Figure 2). Tissue samples from epididymis and testis were taken and immediately transported to the microbiology laboratory and the main part of the specimen was sent to pathology. Ziehl-Neelsen stain and microscopy of testicular tissue revealed AFB too (Figure 3) and after very thorough microscopy also one AFB was found in the epididymal tissue (not shown). Low temperature (30°C) cultures from joint fluid in the meantime grew colonies suspicious from Mycobacterium marinum and this was confirmed GenoType Mycobacterium CM/AS test. Cultures from testicular and epididymal tissue were negative despite positive microscopy (Table 1). Most likely explanation of this was an ongoing antibiotic treatment. Orchiectomy incision healed-up by primary intention.

Table 1. Summary of culture results on various media. Material

Joint fluid

Decontamination

no

Löwenstein-Jensen 1 Löwenstein-Jensen 2 Ogawa Šula

+/14d +/14d +/14d +/14d

Testis yes

no

yes

no

+/14d +/14d +/14d +/14d

C* C* C* C*

-/63d -/63d -/63d -/63d

C* C* C* C*

Epididymis yes -/63d -/63d -/63d -/63d

BACTEC MGIT 960 +/14d +/14d -/63d -/63d -/63d -/63d Decontamination with N-acetyl-L-cysteine was performed and both samples were cultured; + or – indicate positive or no growth; number indicates days after which the results were assessed, C* - bacterial contamination. Culture at Löwenstein-Jensen medium was duplicated to increase the chance of positive

identification. Tissue (testis and epididymis) samples were sent for the confirmation to the reference laboratory as well. The comparison of the sample from MM strain acquired the joint fluid and sample of the testicular tissue by 16S rDNA PCR confirmed the same mycobacterial strain. Histology of the removed testis and epididymis showed multiple small (1-6 mm) and coinciding epitheloid granulomas with central caseous necrosis consistent with miliary testicular infection and severe fibrocaseous inflammation with massive central caseous necrosis was present in the epididymis. The fibrocaseous inflammation was continuously spreading onto testis.

Because of the insufficient clinical response in the area of the right hand the treatment was later changed based on results of drug sensitivities (Tables 2 and 3) to a combination of amikacin, ciprofloxacin, ethambutol, cycloserine and pyrazinamide.

Table 2. Sensitivity of isolated Mycobacterium marinum strain to antituberculotics (S = sensitive, Rresistant). antituberculotic ethambutol ethionamide pyrazinamide cycloserine kanamycin

result S S S S S

antituberculotic isoniazid streptomycin rifampicin para-aminosalicylic acid

result R R R R

Table 3. Sensitivity of isolated Mycobacterium marinum strain to antibiotics (minimum inhibitory concentration in mg/l). antibiotic amikacin rifabutin = rifampicin ciprofloxacin

results 0,5 1,0 2,0

antibiotic ofloxacin azithromycin clarithromycin

result 32,0 >32,0 1,0

Conclusions Despite being the most common non-tuberculous mycobacterium in humans, testicular and epididymal involvement with Mycobacterium marinum was never reported before either in immunocompetent or immunusupressed individuals. There are also very rare report on epididymitis

and/or orchitis with other tuberculous mycobacteria (M. africanum13, M. bovis14) and nontuberculous (M. avium-intracellulare complex7, 15, 16) mycobacteria. The key to the successful diagnosis was primarily a multidisciplinary approach beginning with a very thorough history taking, which revealed important information about the finger injury during aquarium cleaning. The diagnosis of systemic spread was based on immunosupression due to several months use of corticosteroids. Clinical presentation of MM infection on the skin is frequently mistaken with bacterial infection or rheumatoid disorder bringing unsuccessful attempts for antibiotic treatment or immunosupression1, 6, 17. Differential diagnosis of scrotal enlargement can include broad range of diseases, but mainly various infections, including tuberculosis following BCG treatment18, and tumors for which it can be misdiagnosed19. Multiple small hypoechoic areas with the testis represent characteristic pattern of miliary orchitis, which was also the case of our patient20. On the other hand non-specific and mycobacterial infections may share very similar features20. There are no specific guidelines for the management of scrotal presentation of non-tuberculous mycobacteriosis. Treatment is usually empiric. Rifampicin, ethambutol, clarithromycin, quinolones, doxycycline, minocycline or trimethoprim/sulfamethoxazole are used most commonly2, 3, 5, 6. Orchiectomy is often performed in cases with insufficient response to the medical therapy.

References 1.

2. 3. 4. 5. 6.

7.

8.

9. 10.

Adhikesavan, L.G. & Harrington, T.M. Local and disseminated infections caused by Mycobacterium marinum: an unusual cause of subcutaneous nodules. J Clin Rheumatol 14, 156-60 (2008). Katoch, V.M. Infections due to non-tuberculous mycobacteria (NTM). Indian J Med Res 120, 290-304 (2004). Rallis, E. & Koumantaki-Mathioudaki, E. Treatment of Mycobacterium marinum cutaneous infections. Expert Opin Pharmacother 8, 2965-78 (2007). Pavlík, I., Mrlík, V., Bodnárová, M. & Novotný, L. Mykobakterióza ryb a rizika infekce člověka. Československá dermatologie 83, 310-314 (2008). Bodnárová, M. et al. Atypická mykobakterióza a úskalí její léčby. Československá dermatologie 83, 305-309 (2008). Streit, M. et al. Disseminated Mycobacterium marinum infection with extensive cutaneous eruption and bacteremia in an immunocompromised patient. Eur J Dermatol 16, 79-83 (2006). Kishihara, Y., Nakashima, K., Nukina, H., Hayashi, J. & Kashiwagi, S. Two cases of acquired immunodeficiency syndrome with disseminated non-tuberculous mycobacterial infection. Kansenshogaku Zasshi 67, 1223-7 (1993). Pandian, T.K., Deziel, P.J., Otley, C.C., Eid, A.J. & Razonable, R.R. Mycobacterium marinum infections in transplant recipients: case report and review of the literature. Transpl Infect Dis 10, 358-63 (2008). Vazquez, J.A. & Sobel, J.D. A case of disseminated Mycobacterium marinum infection in an immunocompetent patient. Eur J Clin Microbiol Infect Dis 11, 908-11 (1992). Ho, P.L., Ho, P., Fung, B.K., Ip, W.Y. & Wong, S.S. A case of disseminated Mycobacterium marinum infection following systemic steroid therapy. Scand J Infect Dis 33, 232-3 (2001).

11. 12.

13. 14. 15. 16. 17. 18.

19. 20.

Kobashi, Y. et al. Clinical evaluation of the QuantiFERON-TB Gold test in patients with nontuberculous mycobacterial disease. Int J Tuberc Lung Dis 13, 1422-6 (2009). Lewis, F.M., Marsh, B.J. & von Reyn, C.F. Fish tank exposure and cutaneous infections due to Mycobacterium marinum: tuberculin skin testing, treatment, and prevention. Clin Infect Dis 37, 390-7 (2003). Perez-de Pedro, I., Bermudez, P., Artero, I. & Jimenez, M.S. Orchiepididymitis due to Mycobacterium africanum. Enferm Infecc Microbiol Clin 26, 600-2 (2008). Mateos Colino, A. et al. Tuberculous epididymitis caused by Mycobacterium bovis. Arch Esp Urol 56, 175-8 (2003). De Paepe, M.E., Guerrieri, C. & Waxman, M. Opportunistic infections of the testis in the acquired immunodeficiency syndrome. Mt Sinai J Med 57, 25-9 (1990). Hartley, R.A. Mycobacterium avium-intracellulare infection presenting as a testicular mass in an immunocompromised patient: a case report. Cases J 2, 8975 (2009). Lovric, S. et al. Fish, flesh and a good red herring: a case of ascending upper limb infection in a renal transplant patient. Clin Nephrol 72, 402-4 (2009). Hoag, N., Pommerville, P.J., Kibsey, P.C., Cavers, D.J. & Eddy, R.J. Tuberculous epididymitis following intravesical Bacillus Calmette-Guerin immunotherapy. Can J Urol 16, 4589-91 (2009). Yu-Hung Lai, A., Lu, S.H., Yu, H.J., Kuo, Y.C. & Huang, C.Y. Tuberculous epididymitis presenting as huge scrotal tumor. Urology 73, 1163 e5-7 (2009). Muttarak, M., Peh, W.C.G., Lojanapiwat, B. & Chaiwun, B. Tuberculous Epididymitis and Epididymo-orchitis: Sonographic Appearances. American Journal of Roentgenology 176, 1459-1466 (2001).