Tuberculosis of the prostate gland masquerading prostate cancer; five cases experience at IGIMS.

OBJECTIVES: Tuberculosis (TB) of the prostate is a very rare disease. Most urologists are not familiar with it. Here, we present our experience with five cases of this disease and a review of literature.
MATERIALS AND METHODS: This is a retrospective study in a tertiary care center (IGIMS, Patna, Bihar, India) from January 2013 to February 2018.
RESULTS: All the patients were in their fourth to sixth decades of life. Lower urinary tract symptom was the most common presentation, predominantly irritative symptoms. A history of pulmonary TB was present in one case. Four out of five cases (80%) had a suspicious prostate on the digital rectal examination (DRE) (hard in consistency). Serum prostate-specific antigen (PSA) level was slightly elevated with a mean of 13.24 ng/ml. Urine analysis revealed sterile pyuria in all patients, and the urine culture was negative. The urine for acid-fast bacilli was positive in one case (20%). Mycobacterium tuberculosis culture test was positive in two cases (40%). The transrectal ultrasonogram showed hypoechoic areas with irregular outlines in three cases (60%) and calcification in two cases (40%). Histopathological examination showed chronic granulomatous prostatitis with few Langhans-type giant cells in four cases (80%). All patients were scheduled to receive 6 months of chemotherapy with isoniazid, rifampicin, and ethambutol or pyrazinamide.
CONCLUSION: TB of the prostate may present like cancer prostate with raised serum PSA and suspicious prostate on DRE; hence, a high index of suspicion with a wide range of investigations may be required to achieve a complete diagnosis of prostatic TB. Copyright:

INTRODUCTION

Tuberculosis (TB) is one of the most important infectious diseases, particularly in developing countries such as India. Approximately, one-third of the world population is infected with TB.[1] It has been estimated that the genus “Mycobacterium” causes more suffering in the humans than all the other bacterial genera combined.[2] Pulmonary TB is the most common form of the disease and comprises 68.4% of all cases. About 20%–25% of cases are extrapulmonary while only 27% of the extrapulmonary TB involves the genitourinary system.[3] TB of the prostate gland is seen in only 2.6% of genitourinary TB (GUTB).[1] TB involving the prostate gland, apart from being rare, can also mimic cancer of the prostate as well as benign prostatic hyperplasia and therefore requires a high index of suspicion.

MATERIALS AND METHODS

This is a retrospective study of a total of five patients who were diagnosed with prostatic TB (PTB) between January 2013 and February 2018 in the Urology Department of IGIMS, Patna, Bihar, India. The case records of these five cases were analyzed for clinical presentations; their urine analyzed for an acid-fast bacilli (AFB) smear and Mycobacterium tuberculosis culture, and a radiological and histopathological examination was done. An online literature search was made from PubMed regarding tubercular prostatitis and approximately 11 articles were found from 1997 to 2017.

RESULTS

All patients were in their fourth to sixth decades of life. Irritative voiding (100%) symptom was the most common presentation. A history of pulmonary TB was present in one case 20 years back. Complete course of anti-TB treatment (ATT) was taken by the patient. All cases were suspected to be prostate cancer on the digital rectal examination (DRE) due to enlarged prostate with hard consistency and nodules. The prostate-specific antigen (PSA) assay was slightly elevated with a mean of 13.24 ng/ml. In one case, PSA was very high (37.8 ng/dl). The urine analysis revealed sterile pyuria in all these patients, and their urine culture was negative. Urine for AFB stain [Figure 1] and urine culture for TB (BACTEC) were positive in two cases (40%). Chest X-ray was normal, erythrocyte sedimentation rate was raised to 80%, and Mantoux test score was positive in 3 (60%) out of five cases. Intravenous urogram was performed in all cases after kidney function test and was normal. All details of the patients are shown in Table 1.

Figure 1

Urine for acid-fast bacilli shows positive acid-fast bacilli

Table 1

The clinical data of all 5 cases

Case number	Age	Clinical feature	Digital rectal examination	Serum PSA	USG/TRUS	Chest x-ray/IVU	Urine for AFB stain, and urine culture for TB (BACTEC)	Histopathological examination	Treatment given
1	60	LUTS with predominantly irritative voiding symptoms	Prostate firm/hard in consistency with nodule	37.8	Multiple hypoechoic areas	NAD	Positive	TB	ATT
2	55	Irritative voiding symptoms	Prostate hard in consistency	11.2	Hypoechoic nodule calcification	NAD	Negative	TB	ATT
3	48	LUTS	Prostate firm/hard in consistency	7.5	Normal	NAD	Negative	TB	ATT
4	44	Irritative voiding symptoms	normal	6.1	normal	NAD	Positive	TB	ATT
5	38	Irritative voiding symptoms	Prostate firm/hard in consistency	4.8	Hypoechoic nodule with calcification	NAD	Negative	TB	ATT

PSA: Prostate-specific antigen, TRUS: Transrectal ultrasonogram, IVU: Intravenous urogram, AFB: Acid-fast bacilli, TB: Tuberculosis, LUTS: Lower urinary tract symptom, ATT: Antituberculosis treatment, USG: Ultra sonogram, NAD: Not associated with disease, MGIT: Mycobacterium growth indicator tube,culture media

Transrectal ultrasonogram (TRUS) showed hypoechoic areas with irregular outlines in four cases (80%) and calcification in two cases (40%) [Figure 2]. The TRUS-guided prostate biopsy showed granulomatous infection with caseous necrosis and Langhans giant cell [Figures 2 and 3]. These areas of caseation in these patients confirmed the diagnosis. Following this, an extensive search, including an intravenous pyelogram test for tubercular foci in the body, was made; however, no lesions in another area were found.

Figure 2

Transrectal ultrasonogram showing hypoechoic area with calcifications

Figure 3

Chronic granulomatous prostatitis with patchy necrosis and few Langhans-type giant cell reactions suggestive of Kochs

All the patients were scheduled to receive 6–9 months of chemotherapy with isoniazid, rifampicin, and ethambutol or pyrazinamide according to the Centers for Disease Control and the American Thoracic Society protocol. They showed improvement in their symptoms on regular follow-up. After 6 months of chemotherapy, all of them became negative for Mycobacterium in their urine and analysis on AFB smear, mycobacterial culture; PSA level also becomes normal.

DISCUSSION

The term GUTB was first introduced by Willbolz et al. It is the second most common form of extrapulmonary TB after lymph node involvement.[4] The primary organ affected in the urinary tract is the kidney and the epididymis in male genitalia.[4] Since PTB is a rare disease, it is generally not properly diagnosed or is underreported. Prostate localization, especially if it is isolated, is rare.[56] It was first described in 1882 by Benchekroun A et al.[5] Its incidence is estimated to be 6.6% of the urogenital TB according to Scotch Brady Urological Institute in Baltimore.

Sporer et al.[7] reported 728 autopsies of TB cases, of which 100 showed prostatic involvement.

In Medlar's[8] series of cases of genital TB, the prostate was involved in all.

Aziz et al. reported a case of a 60-year-old male patient presenting with tubercular prostatitis which mimicked as cancer prostate.[9]

Gupta et al. found that PTB is uncommon and is usually found incidentally following transurethral resection; nevertheless, there are no reports on transurethral resection for the surgery for PTB.[10]

Kulchavenya et al. reported about 93 patients with suspected prostate TB in their study and all underwent prostate biopsy. Their study allowed the confirmation of diagnosis in 32 patients (34.4%): 23 by histology, six by culture, and five by polymerase chain reaction (PCR) (among them, two had positive culture also).[1]

TB of the prostate is a rather rare condition. Cases of tubercular prostatitis and abscess in relatively young or middle-age patient with HIV infection have been reported.[34] TB of prostate results from the hematogenous spread of the microorganisms from the lungs or less often from the skeletal system.[1112] It may also spread from direct invasion from the urethra; however, this route of infection has been questioned.[78]

Primarily prostatic tubercular lesions are very rare.[2] Tubercular infection of the prostate is usually the result of hematogenous spreading.[3] It can also occur as a result of descending infection from the urinary tract or local spreading from the genital tract.[4] Although sexual transmission of M. tuberculosis has been reported, it is extremely rare.[3] Tubercular infection of the prostate results in chronic granulomatous inflammation. The resulting caseation necrosis either heals by fibrosis or causes cavitations and sloughing (i.e., autoprostatectomy, as in the case with poor host defenses).

Initially, the patients are usually asymptomatic or present with nonspecific irritative voiding symptoms or hemospermia. Hemospermia gives a strong suspicion of tubercular infection and its sequelae in the prostate.[2] Sometimes, the disease spreads rapidly and glandular destruction results reducing the volume of semen. Advanced cases may present with perineal sinus.[411] On palpation, most often, the prostate was found to be nontender, nodular, firm to hard, and enlarged Grade I/II.[4] PTB may cause transient elevation of PSA levels that decreases with resolution of inflammation.[13] In our series, serum PSA came down to normal range after 6–8 weeks of ATT.

A confirmed diagnosis required positive cultures, Ziehl–Nielsen staining, PCR, and/or histological examination.[10] However, staining has a low sensitivity (52.7% in one study), especially in extrapulmonary TB, and cultures require up to 8 weeks for maximal sensitivity.[8] PCR is highly sensitive and specific (the sensitivity and specificity of PCR of urine are 95.59% and 98.12%, respectively); however, it is unable to detect whether the infection is biologically active or is in its latent phase.[10] The diagnosis can be confirmed only by prostate biopsy. In our series, the confirmatory diagnosis was made after histopathological examination in all cases.

TRUS of the prostate revealed an enlarged irregular gland with solitary (rare) or multiple irregular hypoechoic zones of varying sizes [Figure 4]. The irregularity disappeared with medical treatment.[12] The TRUS findings are variable, usually showing a heterogeneous echotexture and dystrophic calcification. The tubercular lesions are typically located in the peripheral part and lateral lobes of the prostate.[10] Contrast-enhanced computed tomography (CT) demonstrates these lesions more clearly.[12] Granulomatous prostatitis lesions show low-signal intensity in the peripheral zone on long TR/TE images. A prostatic abscess is seen as an area of intermediate-signal intensity on short TR/TE images and high-signal intensity on long TR/TE images.[12]

Figure 4

Prostatic parenchyma showing granulomatous epittheloid and giant cell

Short-course combination chemotherapy is the standard care for the treatment of this disease.[10]6–9 months' regimens containing rifampicin and pyrazinamide are very effective with the fastest rates of culture conversion and the lowest rates of relapse.[10] However, extensive prostatic involvements may show resistance to medical treatment. In such cases, surgery is used as a second-line intervention.[14]

CONCLUSION

TB of the prostate is relatively rare. Prostatic tubercular lesions are most commonly secondary to a primary focus. A thorough examination to rule out other primary sites should be attempted. With the recent increase in the incidence of TB, clinicians need to be aware of this possibility, considering TB of the prostate in the differential diagnosis of prostatic carcinoma and thus play a role in the early detection of this disease.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.