Cardiopulmonary exercise test to quantify enzyme replacement response in pediatric Pompe disease.

Bar-Yoseph R; Mandel H; Mainzer G; Gur M; Tal G; Shalloufeh G; Bentur L.

Pediatric Pulmonology. 53(3):366-373, 2018 03.

INTRODUCTION: Enzyme replacement therapy (ERT) with Myozyme improved the
prospect of Pompe disease patients. Our aim was to evaluate ERT acute
effect on exercise capacity in pediatric Pompe patients.

METHODS: Five Pompe patients (10-19 years, 4 infantile-onset and 1
diagnosed at 5 years) were evaluated before and 2 days after ERT using
cardiopulmonary exercise testing (CPET), 6 min walking test (6MWT) and
motor function test (GMFM-88).

RESULTS: Preserved normal peak oxygen uptake, 6MWT and motor function
were observed in the relative mild disease and impairment of these
parameters in the more advanced disease. Two days following ERT, three
patients demonstrated changes; one patient (relative mild disease)
increased both oxygen uptake (11%) and walking distance (38%). Second
patient (advanced disease) increased oxygen uptake (11%) while a small
decrease in walking distance in the 6MWT (8%) was observed. Third patient
(advanced disease) decreased oxygen uptake (39%) but increased walking
distance (42%) and motor function score (27%).

CONCLUSIONS: CPET is safe for pediatric Pompe patients. ERT may benefit
exercise capacity in patients with less advanced disease. Individualized
assessment by CPET, 6MWT, and motor function may help ERT adjustment by
providing precise quantification of the response to treatment. Additional
studies are needed to clarify the benefit of this assessment protocol.