eMedicine Specialties > Radiology > Genitourinary

Tuberculosis, Genitourinary Tract

Ali Nawaz Khan, MBBS, FRCS, FRCP, FRCR, LRCP, Chairman of Medical Imaging, Professor of Radiology, NGHA, King Fahad National Guard Hospital, King Abdulaziz Medical City, Riyadh, Saudi Arabia
Muthusamy Chandramohan, MBBS, DMRD, FRCR, Consultant Radiologist, Bradford Teaching Hospitals, UK; Sumaira MacDonald, MBChB, PhD, MRCP, FRCR, Lecturer, Sheffield University Medical School; Endovascular Fellow, Sheffield Vascular Institute

Updated: Sep 17, 2008

Introduction

Background

The genitourinary tract is the most common site, after the lungs, for tuberculous infection. The infection almost always affects the kidneys during the primary exposure to infection but does not present clinically. The spread to the kidneys from the lungs, bone, or a GI tract focus usually is hematogenous. The true incidence of renal tuberculosis may be underestimated, because radiologic findings may be absent and diagnosis is made by urine culture. Genital tuberculosis is usually secondary to renal tuberculous infection.

Renal involvement may be indolent, with a latency period of more than 20 years after the primary infection to the appearance of urinary tract symptoms of hematuria and stone disease. In patients with renal tuberculosis, treatment involves antitubercular drugs, with surgical excision as an adjunct to antitubercular therapy. The urine can be free of bacteria in less than 72 hours, but anatomic changes can progress as part of the healing process. Females with genital tuberculosis may present with infertility, menstrual disorders, and pain. Pregnancy is unusual in the presence of genital tuberculosis. When pregnancy occurs, spontaneous abortion or ectopic pregnancy usually result. As a result of the lack of clinical features, diagnosis of genital tuberculosis may be difficult.

Genitourinary tract tuberculosis. Excretory urography in a patient with renal tuberculosis shows an irregular cavity at the upper pole calyx of the right kidney. Note the multiple tiny calcifications in the liver, spleen, and right adrenal gland due to calcified tuberculous granuloma.

Genitourinary tract tuberculosis. Lobar calcification in a large destroyed right kidney in a patient with renal tuberculosis. Note the involvement of the right ureter.

Genitourinary tract tuberculosis. Ultrasonographic image of the scrotum in a young male patient shows left epididymo-orchitis resulting from tuberculosis.

Pathophysiology

Tuberculosis of the kidneys usually spreads by a hematogenous route from pulmonary disease, although it occasionally may be secondary to tuberculosis of the GI tract or bone. By the time of diagnosis of renal tuberculosis, the primary source of pulmonary infection may be inactive or calcified. True prevalence of renal tuberculosis is underestimated, because radiologic signs may be absent. Moreover, tubercle bacilli are found in 7-29% of urine samples in patients with extrarenal tuberculosis.

The initial renal focus is usually a small tubercle in the glandular and cortical arterioles. With the passage of time, these lesions progress to form necrotizing lesions. The disease spreads to the renal tubules and renal medulla, in which further tubercles develop, usually at the turn of the loop of Henle, coalescing into larger, necrotic, irregular cavities. The cavities usually communicate with the renal collecting system, generally a calyx, with formation of fistulae and stricturing. Eventually, the kidney may become fibrotic and scarred.

The course of renal tuberculosis may be indolent, with the appearance of few, if any, symptoms. Presentation is usually late, and symptoms usually occur as a result of nonspecific urinary tract infection. Constitutional symptoms usually do not occur or are sparse. Renal tuberculosis is bilateral, although radiologic findings are asymmetric and unilateral in 25% of patients. Ultimately, the kidney becomes atrophic, scarred, densely calcified, and nonfunctioning (autonephrectomy) if not appropriately treated.¹

Ureteric involvement occurs as a descending infection secondary to kidney infection. Tubercles may involve the transitional epithelium, causing mucosal granulomas that project into the ureteric lumen. Eventually, fibrosis occurs in the ureter. These pathologic processes can be demonstrated radiologically by the appearance of a beaded, saw-toothed, corkscrew, or pipestem ureter, depending on the stage of disease. Usually, the upper and/or lower third of the ureters are involved. The vesico-ureteric junction may become fixed and patulous, allowing vesico-ureteric reflux. The kidneys are always involved when ureteric tuberculosis is present.

Bladder tuberculous infection is almost always secondary to renal involvement. Initially, interstitial cystitis occurs, eventually causing bladder mucosal ulceration and thickening of the bladder wall. End-stage disease causes scarring and bladder fibrosis, resulting in diminished capacity of the urinary bladder. Bladder wall calcification is uncommon. Bladder tuberculosis may be complicated by fistulae or sinus tract formation, although these complications are rare.

Tuberculosis of the seminal vesicles usually occurs as a result of hematogenous spread. Descending infection is unusual. The same pathologic processes occur as within the bladder (ie, mucosal tuberculomas, ulceration, fibrosis). Calcification is present in only 10% of patients.

Unlike seminal vesicle tuberculosis, tuberculosis of the prostate is usually secondary to descending infection from the kidney. However, the kidneys may occasionally appear normal, suggesting subclinical infection or a hematogenous prostatic infection. The tuberculous cavities or abscesses may discharge into the surrounding tissues, forming sinuses or fistulae to the perineum or rectum (eventually resulting in a watering-can perineum). The scrotum and urethra may be involved, although rarely. Urethral involvement may be complicated by urethral strictures.

Tuberculosis may cause chronic epididymitis and epididymo-orchitis.² Tuberculous granulomas may develop within the testes and epididymis and rarely may be complicated by abscesses and discharging sinuses. Thickening of the scrotal wall and tunica albuginea, as well as moderate hydrocele, also may occasionally be observed.

Female genital tuberculosis is invariably secondary to tuberculosis elsewhere, and spread may be hematogenous, via the lymphatic system, or by direct spread from adjacent organs. Patients usually present with infertility, menstrual irregularity, and pain. Pregnancy is rare in the presence of genital tuberculosis and is often complicated by ectopic pregnancy or spontaneous abortion.

Clinical features of female genital tuberculosis, if any, are nonspecific, and diagnosis may be difficult. A definitive diagnosis of endometrial involvement can be made using endometrial biopsy. The endometrial cavity may be obliterated by adhesions and thick synechia. In end-stage disease, the endometrial cavity may be completely obliterated. Tubal obstruction is common, as are hydrosalpinx and pyosalpinx. Dilatation of the terminal segment can be moderate or marked.³

In end-stage disease, the tubes become rigid and pipelike because of fibrosis, and they lack peristalsis. A wet or dry peritonitis may accompany genital tuberculosis. Surprisingly, tuberculous endometritis is not a significant cause of sterility (<2% of patients).

Frequency

United States

The genitourinary tract is the second most common site of tuberculosis, the most common site being the lung. Renal tuberculosis is associated with active pulmonary tuberculosis in 4-8% of patients. Tuberculous salpingitis is uncommon in the United States and probably accounts for no more than 1-2% of cases. Before the human immunodeficiency virus (HIV) epidemic, approximately 15% of newly reported cases of tuberculosis had extrapulmonary involvement. In the years since, reported cases of extrapulmonary tuberculosis infection have increased.⁴

International

Exact worldwide incidence of genitourinary tuberculosis is unknown. Genitourinary tuberculosis appears to be fairly common in developing countries.

Mortality/Morbidity

Although no specific figures for genitourinary tuberculosis are released, the World Health Organization (WHO) estimates that about one third of the world's population is infected with Mycobacterium, that about 9 million new cases of tuberculosis disease occur each year, and that tuberculosis causes nearly 2 million deaths each year.⁵

Untreated, the end result of renal tuberculosis is autonephrectomy.¹ The exact incidence of infertility in patients with genital tuberculosis is unknown, but in parts of the world where tuberculosis is common, genital tuberculosis is an important cause of infertility.

Race

Incidence of renal tuberculosis varies throughout the developing world, where the infection is common. The disease is more common in higher socio-economic groups, similar to the pattern found in Europe. Renal tuberculosis is uncommon in tropical Africa despite the fact that other forms of tuberculosis are common. High prevalence is observed in Eastern Europe, Asia, and (particularly) Bangladesh, India, and Pakistan. On the Indian subcontinent, renal tuberculosis is associated with diabetes.

Sex

Males are affected more often than are females.

Age

Individuals of any age can be affected, but most patients who present are younger than 50 years.

Presentation

Renal tuberculosis may remain dormant for many years after the kidneys become seeded during the primary tuberculous infection. With reactivation, 1 or more renal abscesses are produced. Patients usually become symptomatic, with extension of the disease to the renal pelvis and ureters causing hydronephrosis. Specific symptoms may be lacking until the hydronephrotic kidney becomes secondarily infected.

Symptoms of frequency and urgency of urination and dysuria may ensue, with development of tuberculous cystitis. However, long before patients become symptomatic, sterile pyuria, albuminuria, and hematuria are present, although cultures for pyogens demonstrate negative results. Diagnosis usually is achieved using imaging, cystoscopy, and culture of acid-fast bacilli from early morning urine specimens. Needle aspiration biopsy is a last resort when urine cultures are negative.

Male genital tuberculosis may present with epididymitis, hydrocele or a palpable testicular mass, and discharging scrotal or perineal sinuses. Tuberculous prostatitis may present with rectal/pelvic pain and dysuria. Acute prostatic inflammation later is replaced by induration and hard nodules, occasionally followed by abscesses. The abscesses may discharge into the surrounding tissues, forming sinuses or fistulae to the perineum or rectum and eventually resulting in a watering-can perineum.

Female genital tuberculosis may present with pelvic pain, menstrual irregularity, and sterility. Diagnosis is based on analysis of biopsy specimens obtained from the endometrium, laparoscopic biopsy specimens, or culture of menstrual fluid or vaginal discharge.⁶

An association between genital endometrial tuberculosis and Asherman's syndrome has been described. In India, it appears to be a common cause of Asherman's syndrome, resulting in oligomenorrhea or amenorrhea with infertility.⁷

The incidence of pulmonary and extrapulmonary tuberculosis has shown an increase since the late 20th century, due mainly to the rising number of people with acquired immunodeficiency syndrome (AIDS) and the development of drug-resistant strains of Mycobacterium tuberculosis. Diagnosis of extrapulmonary tuberculosis may be challenging because of its clinical and radiological spectra, and because it can mimic many other disease entities.⁶ Therefore, to allow early diagnosis and timely management, a high index of clinical suspicion is required, as is familiarity with the spectra of imaging findings .

Preferred Examination

While intravenous urography remains the primary modality used to image patients with renal, ureteric, and bladder tuberculosis, findings of urinary tuberculosis are also detectable using ultrasonography, computed tomography (CT) scanning, or magnetic resonance imaging (MRI).
CT scanning is not only useful in the diagnosis of renal tuberculosis, but also in the assessment of renal function and of the severity of the disease; it may also detect the involvement of other abdominal organs.
Plain radiography may provide a clue to the diagnosis and may guide further imaging.
Because the type and distribution of calcification may be suggestive of tuberculosis, CT scans (with the ability to depict calcification) may be helpful.
MRI is useful when fistulae or tuberculous tracts are formed.
Hysterosalpingographic images may suggest female genital tuberculosis by demonstrating abnormal findings within the uterus and fallopian tubes.
Ultrasonographic findings in the appropriate clinical setting may help to avoid orchiectomy for benign testicular disease. In patients with female genital tract tuberculosis, awareness of ultrasonographic changes associated with tuberculous infection may improve diagnostic accuracy and help the clinician to avoid clinical mismanagement and surgical explorations in patients with genital infections associated with wet-type tuberculosis (peritonitis).

Limitations of Techniques

All imaging findings may be normal in patients with early genitourinary tuberculosis. Genitourinary calcification may occur in patients with diabetes mellitus and schistosomiasis. Brucellosis also may mimic tuberculosis. The differential diagnosis of an adnexal mass is wide. A congenital megacalyx and focal papillary necrosis may mimic renal tuberculosis radiologically. Papillary necrosis can result from tuberculosis. A tuberculous testicular granuloma may mimic a testicular neoplasm on ultrasonographic images.

Small areas of calcification are difficult to detect on MRI scans, although they are pivotal to the diagnosis of tuberculosis. Hysterosalpingographic findings are also nonspecific; blockage of the fallopian tubes is not pathognomonic for tuberculous salpingitis and may occur as a result of other forms of infective processes of the genital tract.

Findings in all imaging modalities used in the diagnosis of genitourinary tuberculosis are essentially nonspecific, because the diagnosis is based on the presence of calcification, cavities, and strictures, which are associated with a long list of differential diagnoses. However, a fairly confident diagnosis can be made in most instances with clinical correlation. In summary, (1) imaging changes are observed late in the disease; (2) in many instances, there is a significant group of differential diagnoses; and (3) the diagnosis is determined by culture, not by imaging.

Differential Diagnoses

Brucellosis
Papillary Necrosis
Pelvic Inflammatory Disease/Tubo-ovarian Abscess
Schistosomiasis, Bladder

Radiography

Findings

Findings in the kidneys

Genitourinary tract tuberculosis. Plain radiograph of the abdomen in a woman with renal tuberculosis shows calcification of varying patterns (curvilinear, amorphous, speckled).

Genitourinary tract tuberculosis. Excretory urography in a patient with renal tuberculosis shows an irregular cavity at the upper pole calyx of the right kidney. Note the multiple tiny calcifications in the liver, spleen, and right adrenal gland due to calcified tuberculous granuloma.

Genitourinary tract tuberculosis. Excretory urography in a patient with renal tuberculosis shows multiple curvilinear calcifications in the left kidney. Note the calyceal dilatation in the upper pole of the left kidney due to infundibular stricture.

Genitourinary tract tuberculosis. Excretory urography in a man with renal tuberculosis shows irregular cavitation of the left upper pole calyx. Note the multiple tiny calcifications in the spleen.

Genitourinary tract tuberculosis. Excretory urography in a woman with a history of tuberculosis of the breast. The film shows irregular cavitation in the lower pole calyx of the left kidney due to renal tuberculosis.

Genitourinary tract tuberculosis. Excretory urography in a patient with advanced renal tuberculosis shows lobar calcification with no excretion of contrast on intravenous urogram.

Genitourinary tract tuberculosis. Lobar calcification in a large destroyed right kidney in a patient with renal tuberculosis. Note the involvement of the right ureter.

Signs of active or inactive extrarenal tuberculosis (such as osseous or paraspinal changes of tuberculosis, as well as old, healed, calcified splenic, hepatic, lymph node, and adrenal granulomas) may be apparent. Chest radiographs may show evidence of active or healed tuberculosis in 50% of patients, with the remaining patients having normal chest studies.
Changes of renal tuberculosis are unilateral in 75% of patients.
A tuberculoma usually starts as a localized, caseating lesion, most commonly in the upper pole of the kidney, although it may arise anywhere.
With time, the nidus of infection enlarges and ruptures into a neighboring calyx, discharging necrotic, caseous material and distorting the calyx. At this stage, a variety of radiologic abnormalities may be demonstrated, including smudged papillae due to surface irregularity of the papillae, a moth-eaten calyx (early sign), irregular tract formation from the calyx to the papilla, and large, irregular cavities with extensive destruction secondary to papillary necrosis. Changes may be detected on intravenous urography, retrograde pyelography, and on some CT and MRI scans.
The kidney enlarges initially but subsequently may return to normal or become atrophic.
Once communication with a tuberculous cavity is established, the involved calyx becomes an ulcerocavernous lesion.
The finding of hydrocalyces with no pelvis dilatation or an atrophic pelvis is highly suspicious for tuberculosis. The cephalic retraction of the inferior medial margin of the renal pelvis at the ureteropelvic junction (UPJ), or the "hiked up renal pelvis," is another suggestive urographic/pyelographic change.
The infection spreads to the stem of the involved calyx, which may develop a stricture, thus sealing off the involved calyx. This change may be apparent as a mass lesion.
Dilated calyces often are associated with infundibular strictures and may be demonstrated radiologically. The lesions may be better depicted on cross-sectional imaging.
If the ulcer or stricture extends to the renal pelvis or to the UPJ, urine outflow obstruction may occur. In this instance, intravenous urogram may show delayed function, clubbed calyces, or absence of function. At this stage, a "putty" kidney may be depicted. Ultrasonography, CT scanning, and MRI can better depict an outflow obstruction.
If tuberculous infection extends directly to the rest of the kidney, the entire kidney becomes a bag of caseous, necrotic pus.
Plain radiographs may reveal dystrophic calcification, but intravenous urography usually shows absence of function, although a faint nephrogram may be demonstrated if some function remains.
Associated renal calculi are found in as many as 20% of patients with renal tuberculosis.
The final outcome of renal tuberculosis is autonephrectomy, which represents a small, shrunken, scarred, nonfunctioning kidney and is often associated with dystrophic calcification.¹
Renal calcification is present in as many as 50% of patients and may appear as an amorphous, granular opacification, which is associated with active, granulomatous infection, and dense, punctate calcification, which is associated with healed tuberculomas.
Shell-like calcification within the renal collecting system and a thinned-out renal cortex are more a feature of autonephrectomy.
Renal infection may extend into the psoas sheath and/or the perirenal or pararenal spaces.

Findings in the ureters

Genitourinary tract tuberculosis. Excretory urography in a patient with tuberculosis of the ureter and bladder. The lower end of the right ureter demonstrates an irregular caliber with an irregular stricture at the right vesico-ureteric junction. Note the asymmetric contraction of the urinary bladder, with marked irregularity due to edema and ulceration.

Although ureteral involvement is usually unilateral, bilateral changes are asymmetric when they occur. The most common site of involvement is the lower third of the ureter.
Mucosal granulomas may be demonstrated as intraluminal filling defects on intravenous urogram or retrograde pyelography.
Mucosal ulceration is difficult to depict radiologically but rarely may show as irregularity in the contrast-filled ureter.
The involved ureter may appear beaded or with a corkscrew configuration as a result of alternating dilatations and strictures.
Ultimately, the ureter may form a rigid, aperistaltic, shortened tube.
See below (bladder) for findings in vesico-ureteric reflux, hydro-ureter, and hydronephrosis.

Findings in the bladder

Genitourinary tract tuberculosis. Intravenous urography series in a man with renal tuberculosis shows marked irregularity of the bladder lumen due to mucosal edema and ulceration (same patient as Image 4 in Multimedia).

When tuberculosis involves the bladder, progressive thickening of the bladder wall occurs with increasing diminution of bladder volume.
Trabeculation may develop.
The vesico-ureteric junction orifice may become fixed and patulous, resulting in vesico-ureteric reflux.
The vesico-ureteric junction may be affected by progressive narrowing, causing stenosis and resulting in bilateral hydro-ureters and hydronephrosis.
Bladder wall calcification is rare.
Bladder tuberculosis may be complicated by fistulae or by sinus tract formation, although these complications are rare and are demonstrated better on CT and MRI scans.

Findings in the prostate

Tuberculous prostatic cavities or abscesses may discharge into the surrounding tissues, forming sinuses or fistulae to the perineum or rectum and eventually resulting in a watering-can perineum. These changes are demonstrated best on MRI scans.
Plain radiographs may show dense calcification within the prostatic bed, which can also be demonstrated on ultrasonographic and CT scans.
Urethrography or a micturating cysto-urethrogram typically demonstrates filling of variable, dilated prostatic ducts associated with destruction of the prostatic parenchyma.
Sloughing and irregular cavitation of the prostate eventually may result in a smooth-walled cavity that replaces the prostate.

Findings in the seminal vesicles

Genitourinary tract tuberculosis. Plain radiograph of the abdomen in a patient with calcified seminal vesicles due to tuberculosis. Note the amorphous and speckled calcification in the right kidney.

Calcification is depicted on plain abdominal radiographs in as many as 10% of patients with tuberculosis of the seminal vesicles. Calcification of the seminal vesicles is more common in patients with diabetes mellitus.

Findings in the epididymis and vas deferens

Calcification of the epididymis and vas deferens may be visualized on plain radiographs of the male pelvis and must be differentiated from diabetes and schistosomiasis.

Findings in female genital tuberculosis

Genitourinary tract tuberculosis. Hysterosalpingogram in a patient with tuberculosis of the uterus. The contour of the uterus is irregular, with nodular filling defects.

Genitourinary tract tuberculosis. Hysterosalpingogram in a patient with tuberculosis of the fallopian tubes shows right-sided hydrosalpinx with an occluded left fallopian tube.

Tuberculosis can affect any part of the female genital tract but more commonly involves the fallopian tubes.

Hydrosalpinx and pyosalpinx are usually large and may appear as soft-tissue masses on plain abdominal radiographs.
The pyosalpinx may be calcified.
Tuberculous tubo-ovarian abscesses may calcify, are observed on either side of the pelvis, and sometimes appear as well-defined, homogeneous masses, occasionally with areas of increased density that presumably are due to the granuloma. Serpiginous or linear calcification can occur in the tubes.
Hysterosalpingographic findings may suggest a diagnosis. Hysterosalpingographic appearances vary as widely as do the pathologic changes observed in this condition.
- Tubal involvement is almost always bilateral, but the degree of involvement varies between the 2 sides.
- Hysterosalpingography (HSG) may demonstrate a flask-shaped dilatation of the fallopian tubes due to obstruction at the fimbria. Occasionally, the obstruction is at the uterine end of the tube; therefore, the tubes are not depicted.
- HSG may demonstrate sacculation with infiltration of contrast material resembling salpingitis isthmica nodosa. Infiltration around the tube, which creates a cloudlike appearance of the delicate sinus tracts, has also been described.
- A characteristic hysterosalpingographic feature suggestive of tuberculosis has been described in which irregular contrast distribution resembling a cotton-wool plug occurs. Focal irregularity and areas of calcification may occur within the lumen of the fallopian tubes.
- Obstruction of the fallopian tubes is not pathognomonic for tuberculosis and may occur with other pathology.
- In end-stage disease, the tubes become rigid, lack peristalsis, and resemble pipelike conduits.
- Within the endometrial cavity, tuberculous endometritis findings include adhesions, which may vary from very thin to very thick synechiae. In end-stage disease, the uterine cavity may be completely obliterated.
- Within the pelvis, calcified lymph nodes and ovaries may be observed.

Degree of Confidence

Early features of renal tuberculosis may be difficult to detect, and the kidneys may appear entirely normal. With the development of a caseating cavity and calcification at the stage of autonephrectomy, a fairly reliable diagnosis can be achieved. Diagnosis of renal tuberculosis can be confirmed by examination of an early morning urine specimen using microscopy, but diagnosis depends on urine culture for tuberculosis. Certain features are highly suggestive of a tuberculous female genital tract, such as an irregular distribution of contrast on HSG, termed the cotton-wool plug appearance.

False Positives/Negatives

Genitourinary tract tuberculosis. Lateral view of the abdomen in a patient with schistosomiasis shows tubular calcification of the ureters in contrast to the speckled calcification in tuberculosis.

Genitourinary tract tuberculosis. Radiograph of the pelvis in a patient with schistosomiasis shows fine linear calcifications of the bladder wall with normal volume. In tuberculosis, the bladder is contracted and demonstrates speckled calcification.

Renal calcification may occur in nephrocalcinosis, which has several causes. Renal hydatid cysts, renal abscesses, and renal artery aneurysms may calcify and mimic renal tuberculosis.

Ureteric calcification more commonly occurs in patients with schistosomiasis, but differentiation from ureteric, tuberculous calcification is fairly reliable. In schistosomiasis, calcification is first observed in the bladder and then extends up the ureter. Ureteric calcification without bladder calcification is most unusual. In tuberculosis, calcification is more amorphous and patchy, and it extends down the ureter; moreover, the bladder is seldom calcified. Multiple strictures and nodules of ureteritis cystica are fairly rare in ureteric tuberculosis.

Calcification may occur within bladder tumors, or calcium may be encrusted on the surface of bladder tumors, which need to be differentiated from bladder tuberculosis. A shrunken bladder may be neurogenic, but the clinical presentation is not that of urinary tuberculosis.

Calcification of the epididymis and vas deferens may occur in patients with diabetes and schistosomiasis, as well as in patients with tuberculosis. Prostatic calcification may be the aftermath of chronic prostatitis, prostatic carcinoma, or diabetes mellitus.

Blockage of the fallopian tubes is not pathognomonic for tuberculous salpingitis and may occur as a result of previous ectopic pregnancy, iatrogenic or developmental causes, pelvic inflammatory disease, or other forms of infective processes of the genital tract.