ABSTRACT
We present the case of a young woman with worsening attacks of muscle pain and rhabdomyolysis beginning at age 14. Initial metabolic testing and electromyography revealed findings of a nonspecific myopathy. Diagnostic options were discussed among the members of a neurogenetics clinic team. Whole-exome sequencing was selected as a first tier test. This testing revealed a known disease causing mutation in the PYGM gene consistent with McArdle disease. We discuss the decision to use whole-exome sequencing in diagnostics and the rationale for making this our choice as a first-level test modality.
Subject(s)
Glycogen Storage Disease Type V/diagnosis , Glycogen Storage Disease Type V/genetics , Myalgia/diagnosis , Myalgia/genetics , Adolescent , Diagnosis, Differential , Female , Genetic Testing , Glycogen Storage Disease Type V/physiopathology , Humans , Myalgia/etiology , Myalgia/physiopathology , Exome SequencingABSTRACT
Guillain-Barré syndrome diagnosis is based on clinical presentation and supportive diagnostic testing. In its early stage, no single, reliable diagnostic test is available. However, a finding of nerve root enhancement on spinal magnetic resonance imaging may be useful. We evaluated the frequency of nerve root enhancement on spinal magnetic resonance imaging in children with Guillain-Barré syndrome. At a single tertiary pediatric center, we conducted a retrospective chart review of children with Guillain-Barré syndrome who had complete spinal or lumbosacral spinal magnetic resonance imaging with gadolinium administration from January 2002-January 2009. Twenty-four consecutive patients were identified. Spinal nerve root enhancement with gadolinium was present in 92% (22/24) of children with Guillain-Barré syndrome on initial spinal magnetic resonance imaging (95% confidence interval, 0.745-0.978). This finding increased to 100% of patients, after two patients underwent repeat spinal magnetic resonance imaging that did reveal nerve root enhancement. Patterns of enhancement were variable, but involved the thoracolumbar nerve roots in all patients. Enhancement of nerve roots with gadolinium on initial spinal magnetic resonance imaging was frequently present in these children with Guillain-Barré syndrome. Spinal magnetic resonance imaging is a sensitive diagnostic test and should be considered an additional diagnostic tool in select cases.
