The Practical of Acute Inflammation
The cardinal signs of inflammation are rubor (redness), calor (heat), tumor (swelling), dolor (pain), and loss of function. Seen here is skin with erythema, compared to the more normal skin at the far rightCells involved in acute inflammation are mainly polymorph nuclear leukocytes (neutrophils)
Types of cells involved in acute inflammation are mainly neutrophils and macrophages which arrive to the area of acute inflammation to phagocytose cellular debris and infectious agents.
The diagram shown here illustrates the process of exudation, aided by endothelial cell contraction and vasodilatation, which typically is most pronounced in venules
here PMN's that are marginated along the dilated venule wall (arrow) are squeezing through the basement membrane (the process of diapedesis) and spilling out into extravascular space.
Seen here is vasodilation with exudation that has led to an outpouring of fluid with fibrin into the alveolar spaces, along with PMN's
numerous neutrophils fill the alveoli in this case of acute bronchopneumonia in a patient with a high fever. Note the dilated capillaries in the alveolar walls from vasodilation with the acute inflammatory process.
The PMN's seen here are in alveoli, indicative of an acute bronchopneumonia of the lung. The PMN's form an exudate in the alveoli. This patient had a "productive" cough
Here is an example of the fibrin mesh in fluid with neutrophils that has formed in the area of acute inflammation. It is this fluid collection that produces the or swelling aspect of acute inflammation
Acute appendicitis is an example of acute inflammation here the surface of the appendix is covered with yellow to tan exudate and hyperemia, including the periappendiceal fat superiorly, rather than a smooth, glistening pale tan serosal surface
Acute appendicitis: acute inflammatory cells infiltrating the whole layers (transmural).
the mucosa shows ulceration and undermining by an extensive neutrophilic exudate. Neutrophils extend into and through the wall of the appendix in a case of acute appendicitis.The neutrophils are seen infiltrating the mucosa and submucosa of the gallbladder in this patient with acute cholecystitis
This example of edema with inflammation : there is marked laryngeal edema such that the airway is narrowed. This is life-threatening. Thus, fluid collections can be serious depending upon their location
This yellow-green exudate on the surface of an inflamed, hyperemic (erythematous) bowel mucosa consists of many neutrophils along with fibrin and amorphous debris from dying cells.(purulent exudate)
Extensive acute inflammation may lead to abscess formation, as seen here with rounded abscesses (the purulent material has drained out after sectioning to leave a cavity) in upper lobe and lower lobe.
Localized collection of pus result in liver abscess. This may be due to ascending bacterial infection or paracitic infestation ( amoebiasis)
Microscopically, the extensive neutrophilic exudate of an acute abscessing pneumonia is seen here. Normal tissues are destroyed in the region of the abscess.
One consequence of acute inflammation is ulceration. This occurs on epithelial surfaces. Here the gastric mucosa has been lost, or ulcerated. A larger ulcer and several adjacent smaller ones with surrounding erythema
An esophageal acute ulcer is shown here in which the squamous mucosa has been lost. In the ulcer base are inflammatory cells and fibrin