eMedicine Specialties > Radiology > Genitourinary

Tuberculosis, Genitourinary Tract

Author: 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
Coauthor(s): 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
Contributor Information and Disclosures

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.

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

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

Other Problems to Be Considered

Diabetes mellitus
Fungal infections
Causes of fallopian tube obstruction
Congenital megacalyx
Focal papillary necrosis
Scrotal sarcoidosis may mimic tuberculosis. Datta and colleagues described a case in which a scrotal ultrasonogram revealed the presence of multiple, intratesticular, hypo-echoic lesions (even though the findings on a chest radiograph and abdominal ultrasonogram were normal).⁸ A CT scan revealed extensive lymphadenopathy. The patient’s clinical status deteriorated following a 3-month trial of antitubercular treatment. A diagnosis of sarcoidosis was entertained, because the blood results revealed hypercalcemia, elevated serum angiotensin-converting enzyme, and an elevated erythrocyte sedimentation rate. The patient showed rapid recovery following corticosteroid therapy.

• Search for CME/CE on This Topic »

• Atresia, Stenosis, and Other Obstruction of the Colon (Pediatrics: Surgery)
• Tuberculosis (Pediatrics: General Medicine)
• Tuberculosis of the Genitourinary System (Urology)
• Tuberculosis (Infectious Diseases)

• Tuberculosis Symptoms
• Tuberculosis Treatment
• Tuberculosis Causes
• Tuberculosis Overview
• Bacterial and Viral Infections Center

• BCG Vaccination Protects Toddlers Against Pulmonary Tuberculosis
• CDC Updates Guidelines for Nucleic Acid Amplification Tests to Diagnose Tuberculosis
• U.S. Tuberculosis Rate Hits All-Time Low: CDC

• Primary Cutaneous Actinomycosis on the Chest Wall
• Emerging Drugs for Active Tuberculosis
• Tuberculosis Reactivation During Immunosuppressive Therapy in Rheumatic Diseases: Diagnostic and Therapeutic Strategies