Salivagram revisited: justifying its routine use for the evaluation of persistent/recurrent lower respiratory tract infections in developmentally normal children.

Purpose: To assess and establish the utility of radionuclide salivagram in the routine evaluation of developmentally normal children with persistent/recurrent lower respiratory tract infection.

Methods: 113 neurodevelopmentally normal children diagnosed with persistent/recurrent lower respiratory tract infection underwent a salivagram and a milk scan on two consecutive days. Frequency of detection of pulmonary aspiration by either procedure individually and increment in detection rates on combining the two were assessed. The agreement between the tests was also studied.

Results: Antegrade pulmonary aspiration was demonstrated using the salivagram in 39.2 % of infants and 16.1 % of children between the ages of 1 and 2 years. No antegrade aspiration was seen in children above the age of 2 years. 44 % of all antegrade aspirations identified were bilateral, while remaining 66 % were into the right lung. Milk scan revealed gastroesophageal reflux in 38 % of children and most commonly in those above the age of 2 years. Diagnosis of pulmonary aspiration as an underlying cause of the lung pathology increased from 38 % with the use of milk scan alone to 53.9 % on combining the procedures. There was a poor agreement between the two procedures (kappa -0.103).

Conclusion: Antegrade pulmonary aspiration can be demonstrated as an underlying cause for persistent/recurrent lower respiratory tract infection in developmentally normal children, with age being an important clinical predictor. Combined use of salivagram and milk scan is warranted to objectively evaluate pulmonary aspiration in children.