Basics Definition

Ruptured aortic aneurysm
• Cardiovascular collapse
secondary to a ruptured
aortic aneurysm may occur
alongside a history of
cardiovascular disease,
high cholesterol, and HTN,
not found with inhalation
anthrax.
•
An x-ray shows mediastinal
widening much like with a
ruptured aortic aneurysm;
however, mediastinal
changes in anthrax occur
early in the infection along
with pulmonary oedema.
18
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Anthrax
Diagnosis
Condition
Differentiating signs /
symptoms
Differentiating tests
Superior vena cava
syndrome
• Cardiovascular collapse
secondary to superior vena
cava syndrome must be
differentiated from inhalation
anthrax.
•
An x-ray shows mediastinal
widening much like
with superior vena cava
syndrome; however,
mediastinal changes in
anthrax occur early in
the infection along with
pulmonary oedema.
Subarachnoid
haemorrhage
• May be confused with
haemorrhagic meningitis;
however, anthrax usually
has a history of occupational
exposure.
•
A subarachnoid
haemorrhage may
be differentiated from
haemorrhagic meningitis on
CT scan, Gram stain, and
culture of CSF.
Viral gastroenteritis
• Nausea and vomiting may
accompany both diagnoses;
however, ingestion
anthrax often has rebound
abdominal tenderness,
ascites, oropharyngeal
mucosal ulceration,
or pseudomembrane
formation.
[43]
•
Cultures of blood, peritoneal
fluid, or oropharyngeal
secretions will not yield 
B anthracis 
. Standard
blood cultures should be
sent for laboratory testing.
Further confirmatory testing
(immunohistochemical
staining, gamma phage,
PCR assays) must be
performed by a reference
site of the Laboratory
Response Network site,
if in the US, or according
to local protocols in other
countries.
[34]
Cowpox
• Cowpox lesions,
characterised by blister
formation and scab
development resembling
eschar, can occur when
humans are in direct contact
with cowpox ulcers on the
cow’s udder. Cases are
distinguished by historical
clues and contact with the
affected animal.
•
There are no differentiating
tests.