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presents to the emergency department with cough, fever, and shortness of breath. The woman lives alone at home, but spends part of each day shopping and riding public buses. Approximately 4 days previously she had developed an upper respiratory infection. Approximately 2 days ago, she abruptly became much more ill, and her symptoms started worsening, beginning with a single, long, shaking chill. Since that time, she has had fever, pain with breathing, cough, and dyspnea. She decided to come to the emergency department when her temperature at home was 103.4 F. In the emergency department, her temperature is 39.9 C (103.8 F), blood pressure is 90/50 mm Hg, pulse is 120/min, and respirations are 30/min. No breath sounds are heard over her lower left lung field, but they can be heard at other sites.

At this stage of the disease (two days following onset of first symptoms), and before treatment is started, what are the expected histopathologic findings in the affected lung parenchyma?

A. Advanced organization with macrophages and fibroblasts

B. Interstitial lymphomonocytic inflammatory infiltration

C. Intra-alveolar purulent exudate admixed with erythrocytes

D. Resolution of inflammatory exudate with semifluid debris

E. Vascular congestion without intra-alveolar exudation

aaaaaaaa?

C- RED HEPATIZATION- puenmococal pneumonia

my guess

c or e ?? will go for c ....

C.

no breath sounds, oops CCCCCCCCCguys?

The correct answer is C .
Acute lobar pneumonia has classically been subdivided into four pathologic stages.
The initial stage of congestion(choice E) lasts less than 24 hours and is characterized by engorgement of vessels, with intra-alveolar fluid containing few cells, but often, numerous bacteria. Over the following few days, an exuberant intra-alveolar exudate of red cells, neutrophils, and fibrin develops, heralding the stage of red hepatization ( choice C ; so-called because the lung resembles liver at this stage). During the last half of the first week of illness, the red cells begin to break down, but a fibrinous exudate remains in the alveoli; this is the stage of gray hepatization . If death does not supervene, resolution (choice D) occurs in the second week in untreated cases, with digestion of the exudate to leave semifluid debris that are phagocytized, or coughed up. In some cases, the exudate, rather than resolving in this manner, undergoes further organization (choice A) .
An interstitial lymphomonocytic infiltrate (choice B) is characteristic of primary atypical pneumonia, caused by Mycoplasma or viruses.