Case of the Month
Phosphoglycerate mutase deficiency with tubular aggregates in a patient from panama
Article first published online: 21 NOV 2012
Copyright © 2012 Wiley Periodicals, Inc.
Muscle & Nerve
Volume 47, Issue 1, pages 138–140, January 2013
How to Cite
Salameh, J., Goyal, N., Choudry, R., Camelo-Piragua, S. and Chong, P. S. T. (2013), Phosphoglycerate mutase deficiency with tubular aggregates in a patient from panama. Muscle Nerve, 47: 138–140. doi: 10.1002/mus.23527
- Issue published online: 15 DEC 2012
- Article first published online: 21 NOV 2012
- Accepted manuscript online: 20 JUL 2012 12:00AM EST
- Manuscript Accepted: 13 JUL 2012
- CK elevation;
- glycogen-storage disease type X;
- phosphoglycerate mutase;
- tubular aggregates
Phosphoglycerate mutase deficiency (PGAM) is a rare metabolic myopathy that results in terminal block in glycogenolysis. Clinically, patients with PGAM deficiency are asymptomatic, except when they engage in brief, strenuous efforts, which may trigger myalgias, cramps, muscle necrosis, and myoglobinuria. An unusual pathologic feature of PGAM deficiency is the association with tubular aggregates.
We report an African-American patient from Panama with partial deficiency of PGAM who presented with asymptomatic elevation of creatine kinase levels and tubular aggregates on muscle biopsy.
Muscle biopsies showed subsarcolemmal and sarcolemmal tubular aggregates in type 2 fibers. Muscle PGAM enzymatic activity was decreased and gene sequencing revealed a heterozygous mutation in codon 78 of exon 1 of the PGAM2 gene, which is located on the short arm of chromosome 7.
PGAM deficiency has been reported in 14 patients, 9 of whom were of African-American ethnicity, and in 5 (36%) tubular aggregates were seen on muscle biopsy. Contrary to previously reported cases, our patient was initially asymptomatic. This further expands the PGAM deficiency phenotype. Muscle Nerve, 2013