Community-acquired Pneumonia, Pneumonia, Pneumococcal
Conditions
Keywords
quantitative polymerase chain reaction, qPCR, autolysin, lytA, Pneumococcal pneumonia, Diagnostics, Community-acquired Pneumonia, Antibiotic resistance
Brief summary
The purpose of this study is to evaluate the added diagnostic value of a quantitative polymerase chain reaction targeting the lytA gene in detecting pneumococci in patients with community-acquired pneumonia.
Interventions
DIAGNOSTIC_TESTLytA targeted quantitative polymerase chain reaction (qPCR)
LytA qPCR and cultures will be performed on samples of the upper respiratory tract (nasopahrynx, oropharynx, saliva, sputum if available)
Sponsors
Medical Center Alkmaar
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
Yes
Inclusion criteria
Patients: * Age 18 years or above; * Presentation at the emergency department (ED); * Working diagnosis of CAP at the ED with the presence of at least two of the following criteria: 1. New or worsened coughing; 2. Production of purulent sputum or change in sputum colour; 3. Temperature \>38.0 ⁰C or ≤36.0 ⁰C (tympanic); 4. Auscultatory findings consistent with pneumonia, including rales, evidence of pulmonary consolidation (dullness on percussion, bronchial breath sounds, rales, or egophony), or both; 5. White blood cell count of \>10x10\^9 cells/L or \<4x10\^9 cells/L or \>15% bands; 6. C-reactive protein level ≥30mg/L; 7. Dyspnea, tachypnea, (\>20 breaths per minute), or hypoxemia (arterial pO2 \<60mmHg or peripheral O2 saturation \<90%). * New consolidation(s) on the chest radiograph or computed tomography (CT); * No other explanation for the signs and symptoms; Control group 1 - Related controls * Being aged 18 years or above; * Close relative of the patient: relative defined as living in the same house as the CAP patient or daily contact; * Is at the hospital at the moment of inclusion of the CAP patient or is willing to come for testing within 7 days; Control group 2 - Unrelated healthy individuals * Being aged 18 years or above; * Subject with a preoperative appointment with the anaesthiologist for a planned surgical procedure; * Age matched to a included CAP patient (+-10 years); * Time matched to a included CAP patient (up to 14 days after inclusion of the CAP patient); * Gender matched to a included CAP patient. Control group 3 - Patients with stable COPD * Being aged 18 years or above; * Diagnosis of COPD confirmed with spirometry (GOLD criteria 2017)(76); * Stable disease. Control group 4 - Patients with exacerbation of COPD * Being aged 18 years or above; * Diagnosis of COPD confirmed with spirometry (GOLD criteria 2017)(76); * Diagnosis of exacerbation of COPD: defined as an acute event characterised by a worsening of the patient's respiratory symptoms that is beyond normal day-to-day variations and leads to a change in medication (76). * Presentation at emergency department with the suspicion of an exacerbation.
Exclusion criteria
In general: * Recent pneumonia (\< 1 month) or pneumonia in last 3 months with known pneumococcal aetiology with one of current diagnostics; * Was included in the study group before; * Not capable of understanding information needed to sign informed consent. Patients: * Aspiration pneumonia; * Hospitalisation for two or more days in the last 14 days; * History of cystic fibrosis. For all control groups: * Fits inclusion criteria for patient group; * Present or recent hospitalisation (14 days); * Fits inclusion criteria for patient group; * Use of antibiotics in the last 14 days, including maintenance antibiotic therapy. Control group 1 and 2 - Related healthy controls and unrelated healthy individuals * Active infectious respiratory complaints defined as defined as two or more respiratory symptoms (cough, nasal congestion, runny nose, sore throat or sneezes); * Temperature \>38.0 ⁰C; * Fits inclusion criteria for control group 3 or 4; * Chronic pulmonary disease: COPD, asthma, cystic fibrosis, bronchiectasis. Control group 3 - Patients with stable COPD * Temperature \>38.0 ⁰C; * Stable disease; * Fits inclusion criteria for control group 4; * Recent exacerbation (\<1 month) defined as increased respiratory symptoms with need of antibiotic and/or corticosteroid therapy; * History of cystic fibrosis. Control group 4 - Patients with exacerbation of COPD * Current pneumonia; * Recent exacerbation (\<1 month) defined as increased respiratory symptoms with need of antibiotic and/or corticosteroid therapy; * Fits inclusion criteria for control group 3; * History of cystic fibrosis.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| qPCR diagnosed pneumococcal pneumonia | 1 day, day of inclusion | Occurrence of qPCR proven pneumococcal pneumonia (CAP with S. pneumoniae detected by qPCR in at least one of the samples with a positive lytA qPCR and a DNA copy number above the determined cut-off value) using the cut-off value in at least one of the specimens at inclusion. The cut-off value will be determined in this study, see secondary objective. |
| Pneumococcal pneumonia with usual tests | 1 day, day of inclusion | Occurrence of pneumococcal pneumonia proven by at least one of the routine microbiological tests (urine antigen test, blood culture and/or sputum culture). The difference between outcome measure 1 and 2 is the added diagnostic value. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Number of DNA copies of S. pneumoniae in all lytA qPCR positive study subjects | 1 day, day of inclusion | The number of DNA copies of every study subject with a positive qPCR will be determined. The optimal cut-off value will be determined to distinguish between colonisation and infection by comparing the number of DNA copies of controls with a positive lytA PCR and patients with a pneumococcal pneumonia proven by routine microbiological tests. This cut-off value will be used for outcome measure 1 to determine the amount of patients with an qPCR proven pneumococcal pneumonia. |
| Occurrence of positive lytA qPCR at 30 days after inclusion in CAP patients | 30 days | Occurrence of positive lytA qPCR at 30 days after inclusion in CAP patients in the different samples: oropharynx, nasopharynx, saliva and sputum. |
| CURB-65 scores | 1 day, day of inclusion | CURB-65 scores will be determined in CAP patients at moment of inclusion. |
| Procalcitonin | 1 day, day of inclusion | Procalcitonin levels will be determined in CAP patients at moment of inclusion. |
Countries
Netherlands
Outcome results
None listed