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Accuracy of Lung Injury Biomarkers in the Initial Investigation of Patients With Suspected Pneumonia

Diagnostic and Prognostic Accuracy of Surfactant Protein D, Krebs Von Den Lungen, and Chitinase-3-like Protein 1 (YKL-40 ) in the Initial Investigation of Patients With Suspected Pneumonia

Status
Completed
Phases
Unknown
Study type
Observational
Source
ClinicalTrials.gov
Registry ID
NCT04686331
Enrollment
411
Registered
2020-12-28
Start date
2021-03-01
Completion date
2022-06-01
Last updated
2022-09-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Community-acquired Pneumonia

Keywords

surfactant protein D, Krebs von den Lungen, YKL-40 C, pneumonia, lung injury, diagnostic markers, prognostic markers, emergency department

Brief summary

The aim of this study is to investigate the diagnostic and prognostic value of surfactant protein D, Krebs von den Lungen (KL-6), and Chitinase-3-like protein 1 (YKL-40) in the initial investigation of patients hospitalized with suspected pneumonia. This to improve the diagnosis of pneumonia, contribute to a more rapid and accurate antibiotic treatment, and assess disease severity to predict short-term and long-term mortality in community-acquired pneumonia patients.

Detailed description

Community-acquired pneumonia (CAP) is one of the most common infection diseases in the emergency department (ED). Diagnosis of pneumonia is challenging as symptoms are often weak and nonspecific and the current methods for focal and etiological diagnosis have low sensitivity and specificity and often deliver results after the antibiotic treatment decision has been made. The abundant and restricted expression of surfactant protein D (SP-D) within the lung makes this protein a specific marker for lung disease. Krebs von den Lungen-6 (KL-6) is expressed in the lung and is a diagnostic and prognostic marker of interstitial lung disease. The inflammatory glycoprotein Chitinase-3-like protein 1 commonly known as YKL-40 is associated with severity of interstitial lung disease. The value of these lung injury markers for diagnosing pneumonia needs further investigation. The investigators hypothesize that surfactant protein D, Krebs von den Lungen (KL-6), and Chitinase-3-like protein 1 (YKL-40) have an impact on diagnosing, prognosis, and treatment of patients with verified CAP. The objectives of the study are: * To investigate the diagnostic accuracy of surfactant protein D, Krebs von den Lungen (KL-6), and Chitinase-3-like protein 1 (YKL-40) in the diagnosis of CAP * To identify the prognostic value surfactant protein D, Krebs von den Lungen (KL-6), and Chitinase-3-like protein 1 (YKL-40) in relation to adverse events in patients with verified CAP

Interventions

DIAGNOSTIC_TESTBiomarkers for pneumonia

Blood samples will be collected by a medical laboratory technologist and transferred to the local laboratory for analysis of surfactant protein D, Krebs von den Lungen (KL-6), and YKL-40. Laboratory staff will be blinded to participant diagnosis and outcome. None of the biomarkers will be available to the treating physician. * Diagnostic test of surfactant protein D - will be quantified using enzyme-linked immunosorbent assay (ELISA)-based analysis * Diagnostic test of KL-6: will be quantified using enzyme-linked immunosorbent assay (ELISA)-based analysis * Diagnostic test of YKL-40 - will be quantified using enzyme-linked immunosorbent assay (ELISA)-based analysis

Sponsors

University of Southern Denmark
Lead SponsorOTHER

Study design

Observational model
COHORT
Time perspective
PROSPECTIVE

Eligibility

Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Suspicion of APN assessed by the receiving physician at the ED

Exclusion criteria

* If the attending physician considers that participation will delay a life-saving treatment or patient needs direct transfer to the intensive care unit. * Admission within the last 14 days * Verified COVID-19 disease within 14 days before admission * Pregnant women * Severe immunodeficiencies: Primary immunodeficiencies and secondary immunodeficiencies (HIV positive CD4 \<200, Patients receiving immunosuppressive treatment (ATC L04A), Corticosteroid treatment (\>20 mg/day prednisone or equivalent for \>14 days within the last 30 days), Chemotherapy within 30 days)

Design outcomes

Primary

MeasureTime frameDescription
Verified and non-verified community acquired pneumonia (CAP)2 months after patient dischargeThe decision of whether patients admitted with suspicion of CAP actually has a final diagnosis of CAP is based on a combination of all findings during admission. The verification of diagnosis requires human handling, interpretation and judgment. Therefore, in this study, an expert panel will define the reference standard for the diagnosis CAP. The expert panel consists of two independent consultants from the emergency department with significant experience in emergency medicine and acute infections. They will individually determine whether or not the patient admitted suspected with CAP actually had this diagnosis. The final diagnosis will be based on all available relevant information from the patient medical record including HR-CT of lungs. A standardized template will be used. Disagreement will be discussed until a consensus is reached.

Secondary

MeasureTime frameDescription
Length of staywithin 60 days from current admission to the emergency departmentdays spent in hospital during current admission
the number of participants who died within 30 dayswithin 30 days from arrival daybinary - 30-days mortality
Intensive care unit treatmentwithin 60 days from admission to the emergency departmenttransfer to ICU during current admission (binary outcome)
Readmissionwithin 30 days from day of dischargebinary
In-hospital mortalitywithin 60 days from admission to the emergency departmentbinary
The number of participants who died within 90 dayswithin 90 days from arrival daybinary - 90-days mortality

Other

MeasureTime frameDescription
Bacteriuriaurine collected within 4 hours of arrival to emergency departmentBinary outcome defined by microbiologist on urine culture analysis
Microbial agentsresults within 7 days from sputum sample collectionMicrobial agents (bacteria and viruses) identified in standard culture, PCR and multiplex PCR. Sputum or tracheal secretion samples are collected within 1 hour from patient admission.
Diagnostic capabilities of Ultra low-dose computer thermography for pneumoniaWithin 24 hours from hospital admissionTrue positive, true negative, false positive and false negative for ultra low-dose computer thermography for pneumonia.
Diagnostic capabilities of lung ultrasound for pneumoniaWithin 24 hours from hospital admissionTrue positive, true negative, false positive and false negative for lunge ultrasound for pneumonia.
Diagnostic capabilities of chest x-ray for pneumoniaWithin 24 hours from hospital admissionTrue positive, true negative, false positive and false negative for chest x-ray for pneumonia
Level of infection markersblood collected with 4 hours of arrival to emergency departmentConcentration of serum procalcitonin, CRP and suPAR
CURB-65 severity scorewithin 4 hours from admissionConfusion of new onset, Blood Urea nitrogen greater than 7 mmol/L (19 mg/dL), respiratory rate of 30 breaths per minute or greater, blood pressure less than 90 mmHg systolic or diastolic blood pressure 60 mmHg or less and age 65 or older. The score stratify patients to groups 1 (mild pneumonia), 2 (moderate pneumonia) and 3-5 (severe pneumonia).
Pneumonia severity index (PSI)within 4 hours from admissionRisk classes to predict the severity of pneumonia. Scores are given based on demographics, comorbidity, clinical measurements and physical Exam Findings (\<70 = Risk Class II, 71-90 = Risk Class III, 91-130 = Risk Class IV, \>130 = Risk Class V)

Countries

Denmark

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026