Diagnostic ultrasound ( PDFDrive )

CHAPTER 9 The Kidney and Urinary Tract 329
A
B
FIG. 9.26 Xanthogranulomatous Pyelonephritis. (A) Sagittal sonogram shows an enlarged hypoechoic kidney and a large showing staghorn
calculus. (B) Corresponding contrast-enhanced CT demonstrates a diffusely enlarged left kidney, multiple intrarenal abscesses, and a large, central
obstructing calculus.
A
B
FIG. 9.27 Papillary Necrosis. (A) Sagittal and (B) transverse sonograms show swollen bulbous papillae.
Sonographic Findings of Papillary Necrosis
Swollen pyramids
Papillary cavitation
Adjacent clubbed calix
Sloughed papilla in collecting system that can calcify and
simulate a stone
Sloughed papilla may cause obstruction
Hydronephrosis may develop if the sloughed papilla obstructs
the ureter.
Tuberculosis
Urinary tract tuberculosis (TB) occurs with hematogenous seeding
of the kidney by Mycobacterium tuberculosis from an extraurinary
source (typically lung). Urinary tract TB usually manifests 5 to
10 years ater the initial pulmonary infection. Chest radiographs
may be normal (35%-50% of patients) or may show active TB
(10%) or inactive healed TB (40%-55%). Most patients present
with lower urinary tract signs and symptoms that include frequency,
dysuria, nocturia, urgency, and gross or microscopic
hematuria, whereas 10% to 20% of patients are asymptomatic. 48
Urinalysis indings include sterile pyuria, microscopic hematuria,
and acidic pH. TB is deinitively diagnosed with acid-fast bacilli
urine cultures; however, this usually requires 6 to 8 weeks for
growth.
Although both kidneys are seeded initially, clinical manifestations
of urinary tract TB are typically unilateral. he early or
acute changes include development of multiple small bilateral
tuberculomas. Das et al. 49 found that the most frequently
encountered sonographic abnormality was focal renal lesions