Tubercular epididymitis and Epididymo-Orchitis: Ultrasound appearances

 

Raja Kollu^1*, Prachi Kala², Ramprakash H V³, Mary Varunya⁴, Anees Dudekula⁵

 

 

Abstract               Objective: To determine the Ultrasonographic appearances in patients with tuberculous Epididymo-Orchitis and Orchitis and to correlate them with the histopathological findings. Materials and Methods: Total 25patients with 50 hemi scortums of clinically suspected Epididymo-Orchitis and Orchitis with high suspicion of tubercular aetiology were assessed on ultrasonography. Of these 50 hemi scrotums, 12 scortums of 8 patients testicular and epididymal tissues cultures were positive for Mycobacterium tuberculosis. Results: The most detected sonographic findings of tuberculous epididymitis were an enlarged epididymis commonly in the tail region, and marked heterogenous echo texture of the involved epididymis. Sonographic findings of testicular involvement consist of an ill defined focal intratesticular hypoechoic area or diffusely enlarged hypoechoic testis or an irregular margin between the testis and epididymis. In our study Unilateral Epididymo-Orchitis is the most common involvement pattern followed by isolated epididymitis, bilateral Epididymo-Orchitis and isolated orchitis respectively. The sonographic appearances in patients with tuberculous epididymitis are seen to be different from those encountered in nontuberculous epididymitis. Conclusion: Adequate evaluation of patients with high suspicion of Tuberculous Epididymo-Orchitis and Orchitis, by means of scrotal ultrasound coupled with fine needle aspiration cytology is critical to diagnostic accuracy and optimal treatment. Ultrasound significantly helpful to the initial assessment and future management of the patient with follow-up scans ensuring positive response to treatment thereby avoiding surgical intervention.

Key Words: GUTB - Genitourinary tuberculosis, TB – Tuberculosis, TBE - Tuberculous epididymitis, TBE-O - Tuberculous epididymo-orchitis, USG – Ultrasonography.

 

 

 

 

INTRODUCTION

Genitourinary tuberculosis (GUTB) is a chronic granulomatous infection and the most common extrapulmonary site of tuberculosis (TB) representing up to 20 -30 % of all TB cases. Tuberculous infection of the scrotum is rare and occurs in approximately 7% of patients with extrapulmonary disease¹. The epididymis being the commonest structure to be involved, followed by the seminal vesicles, prostate, testis, and the vas deferens². Tuberculous orchitis usually occurs as a result of direct extension from the epididymis³. Present HIV Pandemic has resulted in a global surge in the TB prevalence which in turn resulted in the surge of extra pulmonary TB in endemic areas⁴ Most of the cases are coexist with pulmonary TB or tuberculosis of other parts of lower genitourinary system including bladder, ureter and prostate. Isolated tuberculous epididymitis (TBE) or epididymo-orchitis (TBE-O) is rare⁴ Clinically, TBE-O may mimicthe other testicular conditions like bacterial epididymitis, viral orchitis, infected hydrocele, spermatocele, testicular torsion, scrotal trauma, or neoplasm in healthy patients with no clinical symptoms and signs. This diagnostic dilemma may result in an inappropriate surgical procedure for a potentially curable medical illness, which could have been avoided with anti-TB management⁵ hence accurate differentiation is important for appropriate treatment. High-resolution sonography is currently the best technique for imaging of the scrotum and its contents. In this study, we aim to describe the sonographic appearances of tuberculous epididymitis (TBE)and epididymo- orchitis (TBE-O).A high index of suspicion, scrotal ultrasonography and fine needle aspiration could be quite helpful in the diagnosis.

 

MATERIALS AND METHODS

This is a prospective study conducted in the department of Radio diagnosis and imaging, Vydehi Institute of Medical Sciences and Research Centre (VIMS and RC), Bangalore from Oct 2016 to Aug 2018. Clinically suspected patients of Epididymo-Orchitis and Orchitis with high suspicion of tubercular etiology were included in the study, Subsequently underwent high resolution ultrasonography of the scrotum and Fine needle aspiration cytology (FNAC). All the scans were performed on Phillips Affinity 50G machine using L5-12 MHz high frequency transducer.

RESULTS AND DISCUSSION

Figure 1:                                                                                              Figure 2:

 

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Figure 5:

Figure 1: 47 year old patient with pain and swelling in the scrotum– Ultrasound Scrotum - Right epididymo- orchitis and left epididymitis A)Enlarged, nodular homogenous hypoechoic right epididymis B )Hypoechoic granulomas in the right testis C) Enlarged Heterogeneous Left epididymis with involvement of head, body and tail with normal left testis. D) Left scrotal wall thickening; Figure 2: 42 year old patient with pain and swelling in the left scrotum– Ultrasound Scortum - Left epididymo-orchitis A)Enlarged, heterogeneous hypoechoic Left epididymis with involvement of head, body and tail B ) Multiple small Hypoechoic granulomas in the testicular parenchyma C) Multi loculated left hydrocele with thin septations with in. D) Normal right epididymis and testis; Figure 3: 38 year old patient with pain in the Left hemiscrotum and discharge from scrotal skin surface – Ultrasound Scrotum – Left epididymo- orchitis with scrotal collection and sinus formation; A) Enlarged, Heterogeneous hypoechoic epididymis with increased peripheral vascularity (solid arrow). B) Well defined Hypoechoic granuloma (white arrows) in the testis. C) Hypoechoic area observed independent to epididymis and testis is Collection in the left hemi scrotum; Figure 4: 34 year old patient with Pulmonary and Musculo-Skeletal TB, Presented with Swollen right hemiscrotum and collections in the left gluteal region and left lateral thigh – Ultrasound Scrotum – Right epididymo- orchitis with miliary lesions in testis A) Enlarged, round hypoechoic epididymis with contiguous involvement of adjacent rete testis. B) Multiple small Hypoechoic lesions in rest of the testis - Miliary lesions. C) Heterogeneous Collection in the lateral compartment of thigh; Figure 5: 54 year old patient with bilateral scrotal swelling and ulcer on the right hemiscrotum – Ultrasound Scrotum -Bilateral epididymo- Orchitis A and B) Diffusely Enlarged, oedematous epididymis and testis on both sides C) Calcific speck (Yellow Arrow) in the left epididymal head;

 The study group consists of 25 subjects with 50 hemiscrotums. 12 scrotums of 8 patients testicular and epididymal tissues cultures were positive for Mycobacterium tuberculosis. In our study, Unilateral Epididymo-Orchitis is the most common involvement pattern followed by isolated epididymitis, bilateral Epididymo-Orchitis, and isolated Orchitis respectively. The sonographic appearances in patients with tuberculous epididymitis are seen to be different from those encountered in nontuberculous epididymitis. GUTB is the most common extrapulmonary manifestation after lymphatic TB, representing 2–4% of all cases of tuberculosis and 15% of all non-pulmonary manifestations^3,6. Genitourinary system involvement has been observed in 20% of pulmonary TB cases. TB of the scrotal contents is rare, occurring in about 7% of patients with TB^3,7. Vulnerable population groups at risk for TB infection are the immunocompromised (HIV infection, organ transplants) and those suffering from chronic illness¹. TB of the scrotal contents usually results from retrograde extension from the prostate and seminal vesicles. The tuberculous bacillus can gain entry also via the hematogenous and lymphatic routes. With both hematogenous and direct spread, the epididymal tail is the first structure to be involved,^2,8,9 as it has the rich blood supply and also the first part to be involved in urinary reflux². The inflammatory process may propagate to the rest of the epididymis and finally to the ipsilateral testis or may regress and heal with calcifications⁶. Isolated TB orchitis without epididymitis is very rare^3,7,10. Clinically patients with TB epididymo-orchitis present with a painless or painful scrotal swelling and heavy sensation as principal symptoms^3,10. Ultrasonography (USG) is the best imaging modality of choice for evaluation of TB of scrotum and scrotal contents. In conjunction with USG, Fine needle aspiration cytology (FNAC) has been reported to enhance diagnosis. Characteristic FNAC picture includes epithelioid granuloma with a necrotic background and presence of variable lymphocytes. Ziehl-Neelsen (ZN) stain performed on the slides confirms the presence of numerous acid-fast bacilli⁴. Sonographic patterns of tuberculosis in the scrotum are varied and dependent on the stage of the disease⁶.

Sonographic Appearances of Tuberculosis Epididymitis: Different sonographic echogenic patterns of tuberculosis epididymitis include: (a) Enlarged, hypoechoic and diffusely homogeneous (Figs.1A, 2A); (b) enlarged, hypoechoic and diffusely heterogeneous (Fig.1C); and (c) enlarged, nodular, heterogeneous and hypoechoic (Figs.3A, 4A). Kim et al.⁸ and Drudi et al.⁹ observed that the tail of the epididymis is the preferential site of involvement in tuberculosis epididymitis. Kim et al. suggested that heterogeneous and enlarged epididymis is reliable finding in differentiating tuberculosis from nontuberculous epididymitis. These findings were also confirmed in the series of Chung et al study¹². The heterogeneous appearance of the epididymis is due to various pathologic stages of the disease, which include caseation necrosis, granulomas formation, and fibrosis^8,11,12.

Sonographic Appearances of Tuberculosis Orchitis: Isolated tuberculous Orchitis without epididymis is very rare^11,12. Tuberculosis Orchitis usually result from contiguous extension of disease process through the epididymis. The Gray-scale sonographic appearances of the tuberculous Orchitis include (a) diffusely enlarged heterogeneously hypoechoic testis (Figs.5A, 5B), (b) diffusely enlarged homogeneously hypoechoic testis, and; (c) nodular enlarged heterogeneously hypoechoic testis (Figs.1B, 2B). Drudi et al.⁹ also described another pattern of multiple small hypoechoic nodules (Figs.2B, 4B) in the enlarged testis as a miliary type and suggested that this pattern was a feature of tuberculosis Orchitis. Miliary pattern was also found in two of 18 patients in the series of Chung et al. study^11,12. On Colour Doppler ultrasound examination of TB nodule showslinear peripheral increased vascularity with no abnormal flow in the centre (Fig.3A) which is well correlate with pathological findings that central portion shows, caseation necrosis, and the peripheral portion shows several medium to small sized vessels^1,13 which may help to differentiate TB nodules from other lesions⁶. Bilateral involvement of epididymides is seen in about 25% of patients,¹² and coarse calcifications also favor the diagnosis of a chronic tuberculous infection².

Other sonographic findings in Scrotal Tuberculosis: Other associated ultrasound findings include scrotal skin thickening (Fig.1D), hydrocele (Fig.2C), calcification (Fig.5C), scrotal abscesses formation (Fig.3C), and scrotal sinus tract. Thickening of the scrotal skin is best visualized when compared with the unaffected side. Calcification is frequently seen in the epididymis and the tunica vaginalis testis. Clinical differential diag­noses of scrotal swelling with or without pain include inflamma­tory processes, tumors and testicular torsion. Non- seminomatous tumors are - hetero­geneous masses with cysts and calcifications. Seminomas are homogeneous, hypoechogenic and sharply delineated masses on ultrasound¹⁴. Testicular tumors tend to involve the epididymis in late stages of the disease¹². The presence of epididymal involvement with testicular lesion favors infection rather than tumor, being that orchitis is the complication of epididymitis^1,7. Testicular torsion usually presents with sudden orchalgia and swelling. US Doppler interrogation shows reduced or absent blood flow to the testis, in contrast to the hyperemia seen in inflammation¹. Differentiation of tuberculous epididymo-orchitis from bacterial epididymo-orchitis is the most challenging task as both can present with similar symptoms affecting the epididymis as well as the testis. On Color Doppler ultrasound, marked vascularity observed in pyogenic etiology compared with the linear peripheral flow in the tubercular epididymo- orchitis^1,15. Ultrasound findings in association with histopathology findings are crucial in the diagnosis of scrotal tuberculosis and selecting the appro­priate treatment. Ultrasound is also central in the follow-up and outcome prediction: fibrosis and calcifications are of afavorable outcome, whereas fistula formation is a poor outcome^1,15.

 

CONCLUSION

Tuberculous Epididymo-Orchitis commonly presents as a scrotal mass. The clinical outcome of TBEO depends on prompt diagnosis and effective treatment. Ultrasound in conjunction with histopathology contributed significantly to the initial assessment and future management of the patients with follow-up scans ensuring positive response to treatment thereby avoiding unnecessary surgical intervention. Although Scrotal TB is still rare, it is an important consideration in the differential diagnosis, especially in aimmunocompromised patients.

 

REFERENCES

1. Chirindel A, Martinez F, Gagliardi J, Armm M. Testicular Tuberculosis Without Epididymitis Simulating Neoplasm. Radiol Case Reports. 2008; 3(3):1–6.
2. Batchala P, Sailo S, Wankhar B. Case report: USG of bilateral tuberculous epididymo-orchitis. Indian J Radiol Imaging. 2008; 18(1):76.
3. Michaelides M, Sotiriadis C, Konstantinou D, Pervana S, Tsitouridis I. Tuberculous orchitis US and MRI findings. Correlation with histopathological findings. Hippokratia. 2010; 14(4):297–9.
4. Badmos KB. Tuberculous epididymo-orchitis mimicking a testicular tumour: A case report. Afr Health Sci. 2012; 12(3):396–8.
5. Patricio C, David VA, Mauricio SU, Martín LS, Fernando DTR. Scrotal tuberculosis: a case report and literature review. 2011; 71(1321):176–81.
6. Wallage I, Riley SJ. Case Report Tuberculous epididymo-orchitis: the role of ultrasound. 2010;(Figure 4):195–7.
7. Muttarak M, Peh WC. Case 91: Tuberculous Epididymo-orchitis. Radiology. 2006; 238: 748-751.
8. Kim SH, Pollack HM, Cho KS, Pollack MS, Han MC. Tuberculous epididymitis and epididymo-orchitis: Sonographic findings. J Urol 1993; 150:81-4.
9. Drudi FM, Laghi A, Iannicelli E, Di Nardo R, Occhiato R, Poggi R, et al. Tubercular epididymitis and orchitis: US patterns. Eur Radiol 1997; 7:1076-8.
10. Turkvatan A, Kelahmet E, Yazgan C, Olcer T. Sonographic findings in tuberculous epididymo-orchitis. J Clin Ultrasound. 2004; 32: 302-305.
11. Muttarak M, Peh WC, Lojanapiwat B, Chaiwun B. Tuberculous epididymitis and epididymo-orchitis: sonographic appearances.Am J Roentgenol. 2001; 176: 1459-1466.
12. Chung JJ, Kim MJ, Lee T, Yoo HS, Lee JT. Sonographic findings in tuberculous epididymitis and epididymo-orchitis. J Clin Ultrasound 1997; 25:390-4.
13. Yang DM, Chang MS, Oh YH, Yoon MH, Kim HS, Chung JW. Chronic tuberculous epididymitis: Color Doppler US findings with histopathologic cor- relation. Abdom Imaging 2000; 25:559-562.
14. Marth D, Scheidegger J, Studer UE.Ultrasonography of testicular tumors.Urologia Internationalis 1990; 45(4):237-240.
15. Yang DM, Yoon MH, Kim HS, et al. Comparison of tuberculous and pyogenic epididymal abscesses: clinical, gray-scale sonographic, and color Doppler sonographic features. AJR Am J Roentgenol 2001; 177:1131-1135.