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ABDOMINAL ULTRASOUND
Ultrasound may also be used to diagnose
acquired cystic kidney disease in long-term dialysis
patients (see above).
RENAL TRAUMA
The severity of trauma to the kidney may vary significantly
and therefore a range of findings can be
seen with ultrasound. A direct injury can rupture
the kidney. This will result in blood and/or urine
leaking out into the perinephric space. The nature
of the fluid can be determined by ultrasound
guided aspiration. A large urinoma or haematoma
may be drained percutaneously. The main renal
vessels may also be damaged, causing lack of perfusion
(see Chapter 10).
Causes of haematuria are listed in Table 7.3.
RENAL TRANSPLANTS
Although there are a number of treatment choices
for patients with renal failure including peritoneal
and haemodialysis, undoubtedly the treatment of
choice is renal transplantation.
From the very early days of Carrel’s experimental
attempts at transplantation in the 1900s
(resulting in the Nobel Prize of 1912 26 ), to the
un-immunosuppressed allografting of the 1950s,
the more successful and encouraging outcome of
twin to twin transplants, 27 a better understanding
of tissue rejection and the introduction of azathioprine
and steroid in 1963, 28 and more specifically
ciclosporin A by Calne in the 1970s, 29 have all
Table 7.3
Causes of haematuria
● Urinary tract infection
● Stones
● Neoplasm (renal cell or transitional cell carcinoma in
the kidney, ureter or bladder)
● Prostatic pathology (benign hypertrophy or carcinoma)
● Renal cyst haemorrhage
● Papillary necrosis
● Glomerulonephritis
● Trauma
● Tuberculosis
● Renal infarct
contributed immensely to slow but positive
progress in this field. Improvements in surgical
technique, newer, more effective and less toxic
anti-rejection therapy, the routine use of ultrasound
in the 1970s and then Doppler a decade
later, and the development of interventional radiology
have all combined to make this the successful
operation and clinical outcome we now take so
much for granted.
Although many different imaging modalities are
available, ultrasound is the single most useful
investigation in the postoperative monitoring of
the transplant. Amongst its many roles, it is sensitive
to early PCS dilatation, can be used to guide
biopsy procedures and to guide the drainage of
fluid collections and placement of nephrostomy
tubes.
An early, baseline scan is an essential part of the
postoperative management, and serial scans are to
be recommended.
Normal anatomy
Most renal transplants are heterotopic, that is they
are placed in addition to the diseased, native kidneys,
which remain in situ.
The transplanted organ is usually positioned in
the iliac fossa anterior to the psoas and iliacus muscles.
It lies outside the peritoneal cavity.
Within the UK the majority of transplanted kidneys
are cadaveric, and are harvested with their
main vessels intact, which are then anastomosed to
the recipient iliac artery and vein.
Normal ultrasound appearances
The transplanted kidney is particularly amenable to
ultrasonic investigation; its position relatively near
to the skin surface allows a high frequency transducer
(5 MHz) to be used for better detail. For
visualization of the vasculature or origins of the
transplant vessels a 3.5–4.0MHz probe is normally
required.
The ultrasonic appearances of the transplant kidney
are the same as expected for a native kidney,
allowing for the higher resolution [Fig. 7.24]. The
transplant kidney should be assessed in the same
way as the native organ, that is in two planes.
Features to be observed include: