Diagnostic ultrasound ( PDFDrive )

330 PART II Abdominal and Pelvic Sonography
(Fig. 9.28). Small focal lesions (5-15 mm) were echogenic or
were hypoechoic with an echogenic rim. Larger, mixedechogenicity
focal lesions (>15 mm) were poorly deined. Bilateral
disease was noted in 30% of patients. Most tuberculomas will
heal spontaneously or ater antituberculous therapy. At some
later date (perhaps years later), one or more of the tubercles may
enlarge. With enlargement, cavitation and communication with
the collecting system will occur. he resultant pathologic changes
resemble papillary necrosis; papillary involvement is noted when
a sonolucent linear tract is shown extending from the involved
calix into the papilla. Sot tissue caliceal masses representing
sloughed papilla may be seen. Ater rupture into the collecting
system, M. tuberculosis bacilluria develops and allows the spread
of the renal infection to other parts of the urinary tract. Spasm
or edema in the region of the UVJ may occur, giving rise to
hydronephrosis and hydroureter. Ureteric linear ulcers may also
occur, typically within the distal ureter. Bladder involvement is
seen in 33% of patients with genitourinary tract TB. 49 Early
bladder manifestations include mucosal edema and ulceration.
Early clinical symptoms (dysuria and frequency) are also nonspeciic.
If edema occurs at the bladder trigone, ureteric obstruction
may occur. At ultrasound, early bladder involvement will
appear as focal or difuse wall thickening; the thickening can be
quite extensive (Fig. 9.29).
he later or more chronic changes of genitourinary tract TB
include ibrotic strictures, extensive cavitation, calciication, mass
lesions, perinephric abscesses, and istulas. 48 he chronic changes,
in particular those related to ibrotic strictures, result in functional
renal damage. Strictures may occur anywhere in the intrarenal
collecting system and ureter. he obstruction then results in
proximal collecting system dilatation and pressure atrophy of
the renal parenchyma. With time, calciication in the areas of
caseation or sloughed papilla may occur. If renal infection ruptures
into the perinephric space, an abscess may develop. Perinephric
abscesses may ultimately result in istulas to adjacent viscera.
he hallmark of chronic, upper tract renal TB is a small, nonfunctional,
calciied kidney, the “putty” kidney. In the bladder,
chronic infection and ibrosis result in a thickened, small-capacity
bladder. 48 Speckled or curvilinear calciication of the bladder
wall may rarely occur. 50
Most cases of genitourinary tract TB can be diagnosed with
a combination of intravenous/retrograde urography, ultrasound,
CT, and CT urography. 51 Premkumar et al. 52 demonstrated in
14 patients with advanced urinary tract TB that detailed morphologic
information and functional renal status are best assessed
with CT and urography. Das et al. 53 reported that ultrasoundguided,
ine-needle aspiration (1) may be diagnostic in patients
with negative urine cultures and (2) may conirm a diagnosis of
upper genitourinary tract TB in those patients with suspicious
lesions and positive cultures.
Fungal Infections
Patients with a history of diabetes mellitus, chronic indwelling
catheters, malignancy, hematopoietic disorders, chronic antibiotic
or steroid therapy, transplantation, and intravenous drug abuse
are at risk for developing fungal infections of the urinary tract. 54
Candida Albicans
Candida albicans is the most common fungal agent that afects
the urinary tract. Renal parenchymal involvement, typically
manifested by small parenchymal abscesses, occurs in the context
of difuse systemic involvement. he abscesses may calcify over
FIG. 9.28 Progressive Renal Tuberculosis. Sagittal sonogram shows
small, irregular hypoechoic medullary lesions. Areas of cavitation ultimately
connect to the collecting system. (With permission from Wasnik AP.
Tuberculosis, urinary tract. In: Kamaya A, Wong-You-Cheong J, editors.
Diagnostic ultrasound: abdomen and pelvis. Philadelphia: Elsevier; 2016.
pp. 490-493. 51 )
FIG. 9.29 Urinary Bladder Tuberculosis. Transverse sonogram
shows irregular mucosal thickening, particularly at the ureteric oriice—a
characteristic feature of early bladder tuberculosis. (With permission
from Wasnik AP. Tuberculosis, urinary tract. In: Kamaya A, Wong-You-
Cheong J, editors. Diagnostic ultrasound: abdomen and pelvis. Philadelphia:
Elsevier; 2016. pp. 490-493. 51 )