Related Experiment Video
Updated: Jun 19, 2026
04:25
Capsular Serotyping of Streptococcus pneumoniae Using the Quellung Reaction
Published on: February 24, 2014
IMMUNOLOGICAL REACTIONS OF PNEUMONIC PLEURAL FLUIDS
1Thorndike Memorial Laboratory, Second and Fourth Medical Services (Harvard), Boston City Hospital, and the Department of Medicine, Harvard Medical School, Boston.
The Journal of Experimental Medicine
|October 30, 2009
Summary
Pleuritic exudates in lobar pneumonia can be sterile or infected. Sterile fluids contain antibodies, while infected fluids lack them due to soluble specific substance, impacting treatment effectiveness.
Area of Science:
- Immunology
- Infectious Diseases
- Pulmonary Medicine
Background:
- Pleuritic exudates in lobar pneumonia present unique immunological characteristics.
- Understanding the antibody content in these fluids is crucial for diagnosing and treating pneumonia.
- The presence of soluble specific substance may interfere with immune responses.
Purpose of the Study:
- To investigate the presence and concentration of antibodies and therapeutic sera in sterile versus infected pleuritic exudates.
- To determine the influence of soluble specific substance on antibody levels in infected exudates.
- To compare antibody and serum concentrations in pleural fluid with those in blood serum.
Main Methods:
- Analysis of pleuritic exudate and blood serum samples from patients with lobar pneumonia.
- Detection and quantification of actively acquired antibodies.
- Identification of horse serum and heterologous antibodies in serum-treated patients.
- Assessment of soluble specific substance in infected fluids.
Main Results:
- Sterile exudates contain actively acquired antibodies comparable to blood serum.
- Infected exudates lack these antibodies, likely due to soluble specific substance.
- Serum-treated patients' exudates contain therapeutic horse serum and antibodies.
- Concentrations of horse serum and antibodies in pleural fluid generally mirror those in blood serum.
Conclusions:
- Antibody presence in pleuritic exudates differentiates between sterile and infected cases.
- Soluble specific substance in infected exudates neutralizes antibodies, affecting immune response.
- Therapeutic sera administered to patients are detectable in pleural fluids.
- Findings support the role of immunological factors in pneumonia exudate composition.
Related Concept Videos
01:25Pleural Effusion I: Introduction
Pleural effusion is an abnormal fluid accumulation in the pleural cavity, a narrow space between the lungs and the chest wall. It is not a disease per se but rather a symptom or indication of an underlying disease. In normal circumstances, this space contains a small amount of fluid (5 to 15 mL), a lubricant facilitating the non-frictional movement of the pleural surfaces.
There are two main types of pleural effusion: transudative and exudative. They are differentiated using Light's criteria,...
There are two main types of pleural effusion: transudative and exudative. They are differentiated using Light's criteria,...
01:28Pleural Effusion II: Symptoms and Management
Pleural Effusion Overview
A pleural effusion is the abnormal collection of fluid between the parietal and visceral pleura layers of tissue that form the lining of the lungs and chest cavity. It can occur independently or due to surrounding parenchymal diseases, such as infection, malignancy, or inflammatory conditions.
Clinical Manifestations:
A pleural effusion is the abnormal collection of fluid between the parietal and visceral pleura layers of tissue that form the lining of the lungs and chest cavity. It can occur independently or due to surrounding parenchymal diseases, such as infection, malignancy, or inflammatory conditions.
Clinical Manifestations:
01:29Pneumonia II: Pathophysiology
The pathophysiology of pneumonia involves the following steps:
01:13Pleura of the Lungs
The lungs are nestled in a cavity, shielded by the pleura. The pleura, a form of serous membrane, wraps around each lung. This membrane arrangement consists of two layers: the visceral and parietal pleurae. The visceral pleura lines the surface of the lungIn contrast, the parietal pleura is the outer layer and contacts to the thoracic wall, the mediastinum, and the diaphragm. The hilum is the point of connection between the visceral and parietal layers. The space between the parietal and...
01:30Pneumonia III: Complications and Assessment
Pneumonia poses the potential for numerous complications that warrant consideration. These complications include the following:
01:30Pleural Disorders: Types and Brief Description
The pleura is a vital part of the respiratory system. It's a double-layered membrane surrounding the lungs and lining the chest cavity. The two layers of the pleura are: