TY - JOUR
T1 - Fasting as a provocative test in neuromuscular diseases
AU - Carroll, James Edwin
AU - DeVivo, Darryl C.
AU - Brooke, Michael H.
AU - Planer, G. James
AU - Hagberg, James H.
N1 - Funding Information:
Supported by a center grant from the Muscular Dystrophy Association, NHLBI Training Grant S-T32-HL-0708 entitled “Multidisciplinary Heart and Vascular Diseases,” and USPHS Grant RR-00036 from the Division of Research Facilities and Resources.
PY - 1979/6
Y1 - 1979/6
N2 - A 38-hr fast was used as a provocative test in patients suspected of having defects in muscle substrate utilization. In five controls and nine patients, exercise capacity and respiratory exchange ratio were determined before and at the end of the fast. Blood was collected at intervals during the fast from ten controls and nine patients for creatine kinase (CK), free fatty acids, (FFA) β-hydroxybutyrate, acetoacetate, free and total carnitine, glucose, and alanine. Two patients with myophosphorylase deficiency had increased exercise capacity, and a marked fall in CK, and one had a lesser fall in blood glucose than normal at the end of the fast. Two patients with known lipid myopathies (carnitine deficiency and carnitine palmityl transferase deficiency) had decreased exercise capacity and apparent increased dependence on carbohydrate metabolism during the fast. Carnitine concentrations became even more abnormal in the patient with carnitine deficiency during fasting. Several patients with less well-defined defects were also significantly different from the controls in several respects, indicating that the fast might be useful for finding new defects.
AB - A 38-hr fast was used as a provocative test in patients suspected of having defects in muscle substrate utilization. In five controls and nine patients, exercise capacity and respiratory exchange ratio were determined before and at the end of the fast. Blood was collected at intervals during the fast from ten controls and nine patients for creatine kinase (CK), free fatty acids, (FFA) β-hydroxybutyrate, acetoacetate, free and total carnitine, glucose, and alanine. Two patients with myophosphorylase deficiency had increased exercise capacity, and a marked fall in CK, and one had a lesser fall in blood glucose than normal at the end of the fast. Two patients with known lipid myopathies (carnitine deficiency and carnitine palmityl transferase deficiency) had decreased exercise capacity and apparent increased dependence on carbohydrate metabolism during the fast. Carnitine concentrations became even more abnormal in the patient with carnitine deficiency during fasting. Several patients with less well-defined defects were also significantly different from the controls in several respects, indicating that the fast might be useful for finding new defects.
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U2 - 10.1016/0026-0495(79)90023-4
DO - 10.1016/0026-0495(79)90023-4
M3 - Article
C2 - 449706
AN - SCOPUS:0018762627
SN - 0026-0495
VL - 28
SP - 683
EP - 687
JO - Metabolism
JF - Metabolism
IS - 6
ER -