Infectious Diseases in Critical Care Medicine

Table 8

Radiographic Findings

Pathogen

Chest radiographic findings

Comments and other radiologic findings

Category A pathogens

Anthrax (

B. anthracis

)

Inhalation anthrax (36)]

Radiographic findings

(comparing inhalational anthrax and

CAP)

Inhalational anthrax (

N

¼

22)

CAP (

N

¼

188)

Mediastinal widening only

9.1%

1.1%

Pleural effusion only

0%

0%

Infiltrate* only (*

¼

focal density, opacity, or consolidation)

0%

41.5%%

Mediastinal widening and pleural effusion

18.2%

1.1%

Mediastinal widening and infiltrate*

9.1%

4.3%

Pleural effusion and infiltrate*

18.2%

19.1%

Mediastinal widening, pleural effusion, and infiltrate*

45.5%

1.6%

Nonspecific findings

0%

15.4%

Normal

0%

14.9%

Botulism (

C. botulinum

toxin)

Pneumonia complicating fatal cases. Aspiration pneumonia.

Plague (

Y. pestis

)

10% of patients with bubonic plague develop secondary

pneumonia.

Extensive bilateral secondary opacities cannot be distinguished

from primary plague pneumonia or acute respiratory distresssyndrome.

Pneumonic plague from inhalation

has a 4-day incubation period.

In septicemic plague, bilateral infiltrates may represent

secondary plague pneumonia or diffuse alveolar damagefrom sepsis.

Mediastinal, cervical, and hilar adenopathy may not be

consistently present in bubonic and secondary pneumonicplague.

Secondary plague pneumonia appears as bilateral

parenchymal infiltrates that may be initially nodular.Cavitation occurs but is uncommon.

Also described a multilobar air-space disease without extensive

hilar or mediastinal node enlargement.

Pneumonic plague is caused either by hematogenous

disease or direct inhalation.

Smallpox (

V. major

)

Viral and/or bacterial pneumonia has been reported in some

patients.

The skin rash usually appears before pulmonary disease, thus

the diagnosis is almost never in doubt.

Pulmonary edema is a common complication of flat and

hemorrhagic smallpox.

Bones and joints may become involved with periostitis of the

diaphyses of long bones, and patchy destruction of themetaphyses involving the joints (especially the elbow).

“Smallpox handlers disease”

(incubation: 9–12 days aftercontact)

Patients present 9–12 days with fever. Radiographs show ill-

defined nodular opacities in the upper lung fields that maypersist for months. These nodules calcify after severalyears.

Occurs in vaccinated patients who are in contact with smallpox

patients, especially health care workers.

460 Cleri et al.