Table 1: Biomarkers studied in gastroesophageal reflux with respiratory illnesses.

BiosampleSerumSputumBronchoalveolar lavageExhaled airExhaled breath condensate

Studies found223471716
Studies reviewed2112148
Biomarkers studiedEosinophil cationic proteinBile acidsPepsinBile acidsPepsinFeNOPepsin
Neurotrophin 3LLMIIL-4, IL-6LLMIIL-1, IL-8, IL-15IL-4, IL-6
BDNFSubstance PNeurokinin AIFN-gammaMyeloperoxidase8-Isoprostane
Nerve growth factorNerve growth factorMast cell tryptaseLactate dehydrogenaseProtein carbonylspH
8-IsoprostaneHistamineDPPCSP-A, SP-DCalcium
Prostaglandin D2FibrinogenElastase pHMagnesium
Eosinophil cationic proteinChloride