Pepsin As A Biomarker For Aspiration
Condition: Aspiration; Gastroesophageal Reflux
MeSH terms: Gastroesophageal Reflux
Study type: Observational

Summary: 
      Evaluation of tracheal pepsin as a biomarker for aspiration
    

Detailed description: 
      Aspiration is well recognized in children who have chronic lung disease or who are intubated.
      There is a known association between gastroesophageal reflux (GER) and aspiration. The
      distinction between aspiration of swallowed material, such as food and the aspiration of
      refluxed gastric contents is important. Determining whether an aspiration syndrome in an
      individual is due to GER may be difficult. The most widely used test to determine whether GER
      is the cause of aspiration involves staining bronchoalveolar lavage (BAL) fluid for lipid
      laden macrophages (LLM) based on the hypothesis that refluxed and aspirated fluid is
      phagocytosed by tracheal macrophages.

      Pepsinogen is a protein unique to gastric chief cells and also requires acidic conditions for
      activation. Therefore the presence of pepsin in BAL fluid should only be found when gastric
      fluid is aspirated. In previous studies, pepsin has been detected in the tracheal fluid of
      children with chronic lung disease. Thus far, studies of this material have been small, not
      all have control groups, and LLM were not looked for in all studies.

      Based on previous studies and the need to improve diagnostic methods, the following aims are
      proposed:

        1. to determine the frequency of pepsin contamination of children without chronic
           respiratory disease undergoing elective surgery with intubation

        2. to determine frequency of tracheal pepsin and lipid laden macrophages (LLM) in children
           with chronic respiratory disease or symptoms and in children with tracheostomies

        3. to compare the presence or absence and concentration of pepsin to the presence of LLM

        4. to relate the presence or absence and concentration of pepsin to clinical status To
           achieve these aims, BAL fluid will be obtained from subject patients and controls. These
           fluids will be transported to the research lab and stored on ice until analysis.
           Determination of LLM will be done in children undergoing diagnostic bronchoscopy in the
           clinical lab of CHW per routine. BAL analysis will consist of Western blot staining for
           the presence of pepsin. Demographic data will also be collected from the medical record.
    

Intervention name(s): Tracheal Lavage
Intervention type(s): Procedure
Intervention description(s): Tracheal Lavage will be performed on the control population patients and the tracheal fluid obtained from this procedure will be used as the research sample.
Observational model: Case-Control
Time perspective: Prospective
Sampling method: Non-Probability Sample
Study population: 
        Normal children undergoing general endotracheal anesthesia Children with tracheostomies
        Children undergoing bronchoscopy Intubated children in PICU
      
Biospecimen description: 
      Tracheal fluid
    
Keywords: pepsin; aspiration; GE reflux