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Overview :
Salmonella bacteremia occurs in a small percentage of
patients with Salmonella intestinal infections. It can be serious if
intravascular sites become seeded.
Lesions may include:
(1) arterial mycotic aneurysms
(2) infected thrombi, including mural thrombi within the
heart
(3) endocarditis
(4) involvement of vascular grafts
Age of patient: Patients older than 50 years of age are a
high risk group for vascular involvement, with up to 25% developing vascular
infection
Historical findings:
(1) underlying valvular disease
(2) previous vascular surgery, especially with vascular
grafts
Clinical findings - one or more of the following:
(1) peripheral stigmata of bacterial endocarditis
(2) new or changing cardiac murmur
(3) embolic phenomenon
Laboratory evaluation:
• isolation
of Salmonella in blood cultures
• isolation
of Salmonella from resected tissue
•
histopathologic evidence of suppuration in resected tissue, with Gram-negative
bacilli
Grade of bacteremia:
• high grade: more than 50% of 3 or more blood cultures are
positive
• low grade: less than or equal to 50% of 3 or more blood
cultures are positive
Imaging techniques useful to detect vascular or cardiac
involvement:
• ultrasonography
• echocardiography
• arteriography
Therapy:
• If
patient does not have high grade bacteremia and if no vascular structures are
involved, then 7-14 days of intravenous antibiotic therapy is sufficient.
• Short
term antibiotic therapy usually fails with high grade bacteremia or with
involvement of vascular structures; intravenous therapy is recommended for at
least 6 weeks.
• Resection
of the infected area is recommended if feasible.
• If
resection not feasible, then long-term antibiotic therapy may be required.
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