Histochemical Diagnosis of Muscle Phosphofructokinase Deficiency

Abstract

MUSCLE phosphofructokinase (PFK) deficiency in man was first described by Tauri et al¹in a biochemical investigation in 1965. In 1967, Layzer et al²reported additional biochemical and immunologic studies in a second family with this disease. This disorder may be regarded as a fourth type of muscle glycogenosis³in addition to deficiencies of phosphorylase, amylo-1,6-glucosidase (debrancher) and amylo-1,4-glucosidase (acid maltase). The PFK catalyzes the conversion of fructose-6-phosphate (F-6-P) to fructose-1,6-diphosphate (F-1,6-PP); in the absence of this enzyme, glycogen cannot be broken down to lactic acid (Fig 1). The clinical features of this disease are identical to muscle phosphorylase deficiency (McArdle's disease) and include muscle cramps, exercise intolerance, contracture following ischemic work, and myoglobinuria.⁴ At the present time, phosphorylase deficiency can be detected by histochemical means prior to biochemical studies,^5,11but a histochemical method for the detection of muscle PFK deficiency is not