Related Experiment Video
Updated: Mar 12, 2026
Quality-Controlled Sputum Analysis by Flow Cytometry
Published on: August 9, 2021
Application of Droplet Digital PCR in Sputum Samples in Myasthenia Gravis Patients with Pneumonia
Manqiqige Su1, Yeting Luo2, Xiao Huan1
1Department of Neurology and Huashan Rare Disease Centre, Huashan Hospital, Shanghai Medical College, National Centre for Neurological Disorders, Fudan University, Shanghai, People's Republic of China.
Background:
Due to the rapid progression of the pneumonia in patients with Myasthenia gravis (MG), faster pathogen detection techniques are needed. The droplet digital polymerase chain reaction (ddPCR) has the ability to detect pathogens in about 3 h. Thus, this study focused on application of ddPCR in sputum samples in the MG patients with pneumonia and analyzed the association between ddPCR and other laboratory results.
Methods:
We prospectively enrolled 22 MG inpatients with pneumonia and collected 24 sputum samples. All samples were analyzed using traditional culture, ddPCR and metagenomic next-generation sequencing (mNGS) in parallel. Clinical outcomes during hospitalization were documented.
Results:
Among the 24 sputum samples collected from 22 MG patients, ddPCR achieved a 100% positivity rate with the identification of bacteria in all 24 samples, while mNGS also demonstrated a high detection rate, identifying bacteria in 23 of 24 samples (95.8%), and additionally detecting viral and fungal pathogens across multiple cases. In 4 patients with negative sputum culture results, pathogens were identified by both ddPCR and mNGS.
Conclusion:
The ddPCR demonstrated rapid and sensitive identification of predefined bacterial targets and drug-resistance genes, making it suitable for initial diagnostic screening and timely clinical decision-making in MG patients with pneumonia. The speed of ddPCR detection is faster than mNGS and traditional culture, and the results are similar to mNGS and culture, with good consistency.
Insights
Droplet digital PCR (ddPCR) offers rapid and sensitive pathogen detection in Myasthenia gravis (MG) patients with pneumonia. This technique aids timely diagnosis and clinical decisions, showing high consistency with other methods.
Area of Science:
- Medical Diagnostics
- Microbiology
- Genomics
Background:
- Pneumonia progression in Myasthenia gravis (MG) necessitates faster pathogen detection.
- Droplet digital PCR (ddPCR) offers pathogen detection within approximately 3 hours.
Purpose of the Study:
- To evaluate the application of ddPCR in sputum samples from MG patients with pneumonia.
- To analyze the association between ddPCR results and other laboratory findings.
Main Methods:
- Prospective enrollment of 22 MG inpatients with pneumonia, collecting 24 sputum samples.
- Parallel analysis of samples using traditional culture, ddPCR, and metagenomic next-generation sequencing (mNGS).
Main Results:
- ddPCR achieved 100% positivity for bacterial identification in all 24 samples.
- mNGS identified bacteria in 95.8% of samples and also detected viral/fungal pathogens.
- Pathogens were identified by both ddPCR and mNGS in 4 patients with negative sputum cultures.
Conclusions:
- ddPCR enables rapid and sensitive identification of bacterial targets and resistance genes in MG pneumonia.
- ddPCR is suitable for initial diagnostic screening and timely clinical decisions.
- ddPCR offers faster detection than mNGS and culture, with comparable results and good consistency.
Related Concept Videos
01:26Sputum Studies I: Gram Stain, cytology, and Acid-fast smear and culture
Gram Stain
The Gram Stain is an integral part of sputum studies. It involves the staining of sputum, which permits...
01:15Myasthenia Gravis: Diagnostic Tests
The edrophonium test is a diagnostic tool for myasthenia gravis. It involves...
01:30Pneumonia III: Complications and Assessment
01:20Sputum Studies II: Culture and Sensitivity
Sputum culture and sensitivity is a medical procedure used to diagnose bacterial infections in the respiratory tract and select the most appropriate antibiotics for treatment. This process involves analyzing sputum samples of thick and opaque secretions produced in the lungs and airways. These samples are collected from patients and then sent to the laboratory for analysis.
The test can identify various pathogens responsible for respiratory infections, including Streptococcus,...