Lung ventilation-perfusion scintigraphy in children on long-term parenteral nutrition.

Abstract

Pulmonary emboli (PE) are one of the major complications associated with total parenteral nutrition (TPN). Ventilation-perfusion scintigraphy (V/Q) remains the most used test for the diagnosis of PE and follow-up of patients on TPN. The aim of our study was to demonstrate the high prevalence of undiagnosed PE in children on TPN. The medical and imaging files of 64 patients on TPN who underwent V/Q examinations covering the period of 1986-2004 were reviewed. Children were aged between 3.18 months and 21.6 years. TPN was started at birth (range 0-15 years). All children had a normal chest radiograph and no symptoms at the time of the V/Q scan. A comparative analysis between the prevalence of PE and risk factors (number of days per week with lipophilic content of the TPN, bowel inflammation and thrombophilic factors (protein C and S) was performed. Of the 64 patients, 25 (39%) had an abnormal V/Q scan. A total of 29 PE episodes were diagnosed in all patients. Two children had three episodes of PE. The median age at PE diagnosis was 4.6 years. In 17 patients (68%) diagnosis was achieved on the first V/Q scan performed. PE was bilateral in 56% and unilateral in 44%. PE was the main cause of 2 out 15 recorded deaths. All risk factors were associated with an increase in PE prevalence by statistical analysis. PE is underdiagnosed in children on long-term TPN. Lung V/Q scintigraphy is useful in the diagnosis of PE in children with a low pretest probability.