Related Experiment Video
Updated: Aug 29, 2026
Monitoring Neutrophil Elastase and Cathepsin G Activity in Human Sputum Samples
Published on: May 21, 2021
Polymorphonuclear elastase in the early diagnosis of complicated pyogenic pleural effusions
Carmen Alemán1, José Alegre, Rosa M Segura
1Department of Internal Medicine, Hospital General Vall d'Hebron, Autonomous University, Barcelona, Spain. 29261cal@comb.es
Background:
Polymorphonuclear elastase (PMN-E) is a neutrophilic marker that has been implicated in acute inflammatory responses.
Objectives:
To evaluate the accuracy of PMN-E in the diagnosis of complicated pyogenic effusions.
Patients And Method:
We studied 536 patients with pleural effusion of various etiologies. There were 125 pyogenic bacterial effusions (42 typical parapneumonic, 17 borderline complicated parapneumonic and 66 complicated parapneumonic or empyema), 83 tuberculous, 91 malignant, 42 paramalignant, 95 transudates, 28 miscellaneous and 72 effusions of unknown origin. Classic markers (pH, glucose, proteins, adenosine deaminase, LDH, leukocytes and differential count) and the PMN-E level were quantified in pleural fluid. The accuracy of PMN-E as an early marker in the diagnosis of complicated pyogenic infectious effusions was evaluated among pleural effusions that were not diagnosed with classic biochemical markers, radiological findings or Gram stain. Since results of pleural fluid culture and cytological examination are generally available after a 48-hour delay, they were not included as early markers in the initial diagnosis of pleural effusions.
Results:
Early diagnosis of complicated pyogenic bacterial effusions was achieved in only 48 of 66 cases with classic markers. Among those that were not diagnosed with these parameters, a pleural PMN-E value >3,500 microg/l discriminated between complicated and noncomplicated pyogenic bacterial effusions with a sensitivity of 67% and a specificity of 97%.
Conclusions:
PMN-E is useful in the early diagnosis and management of complicated pyogenic infectious effusions, which may be delayed with classic markers.
Insights
Polymorphonuclear elastase (PMN-E) aids in early diagnosis of complicated pyogenic effusions. This neutrophilic marker offers high specificity when classic markers are inconclusive, improving patient management.
Area of Science:
- Pulmonary Medicine
- Infectious Diseases
- Biochemistry
Background:
- Polymorphonuclear elastase (PMN-E) is a neutrophilic marker associated with acute inflammatory responses.
- Accurate and timely diagnosis of complicated pyogenic effusions is crucial for effective treatment.
Purpose of the Study:
- To assess the diagnostic accuracy of PMN-E in identifying complicated pyogenic effusions.
- To evaluate PMN-E as an early diagnostic marker when traditional methods are insufficient.
Main Methods:
- A cohort of 536 patients with diverse pleural effusion etiologies was analyzed.
- Pleural fluid was analyzed for classic markers and PMN-E levels.
- PMN-E's accuracy was evaluated in cases not diagnosed by conventional markers, excluding delayed results from culture and cytology.
Main Results:
- Classic markers achieved early diagnosis in only 48 of 66 complicated pyogenic bacterial effusions.
- In undiagnosed cases, pleural PMN-E >3,500 microg/l distinguished complicated from non-complicated pyogenic effusions with 67% sensitivity and 97% specificity.
Conclusions:
- PMN-E is a valuable tool for the early diagnosis of complicated pyogenic infectious effusions.
- Its utility complements classic markers, especially when diagnosis is delayed.
Related Concept Videos
01:25Pleural Effusion I: Introduction
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
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:
01:30Pneumonia III: Complications and Assessment