%0 Case Reports
%T Neutral lipid storage disease with myopathy and myotonia associated to pathogenic variants on PNPLA2 and CLCN1 genes: case report.
%A Landim JID
%A Ribeiro IS
%A Oliveira EB
%A Freitas HC
%A Brito LA
%A Maia IHM
%A Távora DGF
%A Rodrigues CL
%J BMC Neurol
%V 23
%N 1
%D 2023 Apr 27
%M 37106355
%F 2.903
%R 10.1186/s12883-023-03195-6
%X BACKGROUND: Neutral lipid storage disease with myopathy (NLSD-M) is an autosomal recessive disease that manifests itself around the 3rd to 4th decade with chronic myopathy predominantly proximal in the shoulder girdle. Clinical myotonia is uncommon. We will report a rare case of association of pathogenic variants on PNPLA2 and CLCN1 genes with a mixed phenotype of NLSD-M and a subclinical form of Thomsen's congenital myotonia.
METHODS: We describe a patient with chronic proximal myopathy, subtle clinical myotonia and electrical myotonia on electromyography (EMG). Serum laboratory analysis disclosure hyperCKemia (CK 1280 mg/dL). A blood smear analysis showed Jordan's anomaly, a hallmark of NLSD-M. A genetic panel was collected using next-generation sequencing (NGS) technique, which identified two pathogenic variants on genes supporting two different diagnosis: NLSD-M and Thomsen congenital myotonia, whose association has not been previously described.
CONCLUSIONS: Although uncommon, it is important to remember the possibility of association of pathogenic variants to explain a specific neuromuscular disease phenotype. The use of a range of complementary methods, including myopathy genetic panels, may be essential to diagnostic definition in such cases.