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THE SPLEEN AND LYMPHATIC SYSTEM 145
Haemangioma
The benign haemangioma occurs rarely in the
spleen. As in the liver, it is usually hyperechoic and
well-defined, though may, rarely, contain cystic
areas. 9 Like the hepatic haemangioma, they may
pose a diagnostic dilemma as characterization is
difficult with ultrasound alone. In cases with a low
clinical suspicion of malignancy, such lesions may
be followed up with ultrasound, and tend to
remain stable in size. Less commonly, haemangiomas
may also be multiple.
Abscess
Splenic abscesses are relatively uncommon compared
with their incidence in the liver. They usually
result from blood-borne bacterial infection, but
can also be due to amoebic infection, post-traumatic
or fungal infection. Patients with splenomegaly
resulting from typhoid fever, malaria and
sickle cell disease are particularly predisposed to
the formation of multiple pyogenic abscesses in the
spleen.
Increasingly splenic abscesses are associated with
immunosuppressed patients, patients with AIDS
and those on high-dose chemotherapy. Such
patients become susceptible to invasive fungal
infections which can cause multifocal microabscesses
in the liver and spleen. 10
Patients present, as might be expected, with
LUQ pain and fever.
The ultrasound appearances are similar to liver
abscesses; they may be single or multiple, hyperechoic
and homogeneous in the early stages, progressing
to complex, fluid-filled structures with
increased through-transmission (Fig. 6.5 C, D).
Splenic abscesses are frequently hypoechoic and
it may not be possible to differentiate abscess from
lymphoma or metastases on ultrasound appearances
alone. This applies both in cases of large solitary
abscesses and in multifocal micro-abscesses.
They may also contain gas, posing difficulties for
diagnosis as the area may be mistaken for overlying
bowel.
As with liver abscesses, percutaneous drainage
with antibiotic therapy is the management of
choice for solitary abscesses.
Calcification
Calcification may occur in the wall of old, inactive
abscess cavities, forming granulomatous deposits.
Other infective processes, particularly in association
with AIDS, may cause multiple small calcific
foci throughout the spleen and liver (Fig. 6.6).
SV
A
B
Figure 6.6 (A) Calcification in the spleen in a patient with nephrotic syndrome. Note the left pleural effusion.
(B) Small calcified foci in the spleen of a patient with hepatitis.
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