Lobar pneumonia is a form of pneumonia characterized by inflammatory exudate within the intra-alveolar space resulting in consolidation that affects a large and continuous area of the lobe of a lung.It is one of three anatomic classifications of pneumonia (the other being bronchopneumonia and atypical pneumonia). In children round pneumonia develops instead because the  pores of Kohn which allow the lobar spread of infection are underdeveloped. Mechanism
The invading organism starts multiplying, thereby releasing toxins that cause inflammation and edema of the lung parenchyma. This leads to the accumulation of cellular debris within the lungs. This leads to consolidation or solidification, which is a term that is used for macroscopic or radiologic appearance of the lungs affected by pneumonia. Bacterial pneumonia is mainly classified into lobar and diffuse depending on the degree of lung irritation or damage. Stages
Lobar pneumonia usually has an acute progression. Classically, the disease has four stages:
Congestion in the first 24 hours: This stage is characterized histologically by vascular engorgement, intra-alveolar fluid, small numbers of neutrophils, often numerous bacteria. Grossly, the lung is heavy and hyperemic. Red hepatization or consolidation: Vascular congestion persists, with extravasation of red blood cells into alveolar spaces, along with increased numbers of neutrophils and fibrin. The filling of airspaces by the exudate leads to a gross appearance of solidification, or consolidation, of the alveolar parenchyma. This appearance has been likened to that of the liver, hence the term "hepatization". Grey hepatization: Red blood cells disintegrate, with persistence of the neutrophils and fibrin.
PCE may stand for:

Business and economics
Personal consumption expenditure, or private consumption expenditure
Personal consumption expenditures price index, a measure of inflation

Chemistry and engineering
PCE or eticyclidine, an illegal drug related to Phencyclidine (PCP)
Tetrachloroethylene (perchloroethylene), widely used in dry-cleaning
Pro-opiomelanocortin converting enzyme, an enzyme
Pyrometric cone equivalent, measuring heat in the firing of pottery
Power conversion efficiency, a near synonym for "Energy conversion efficiency" often used in the field of photovoltaics

Computing
Path computation element, a network element used for pathfinding
Principle of computational equivalence, a concept developed by Stephen Wolfram published in the book A New Kind of Science
PC Engine, a video game console

Medicine
Prenatal cocaine exposure, exposure of a fetus to cocaine when a pregnant woman uses the drug
Eticyclidine, a dissociative anesthetic drug

Organizations
Paavai College of Engineering, Namakkal, Tamil Nadu, India
Padmanava College of Engineering, Rourkela, an engineering college in Rourkela, Orissa state, India
Parents for Choice in Education, an advocacy group in Utah, U.S.