J Korean Neurol Assoc.  2025 Feb;43(1):35-39. 10.17340/jkna.2024.0055.

Identification of de novo BSCL2 Asn88Ser Variant with Atypical Presentation of Distal Hereditary Motor Neuropathy Type 5: Clinical Challenge in Diagnosis of Motor Neuron Diseases

• Kim H
• Lee JH
• Won D
• Choi JR
• Shin HY
• Kim SH

• KMID: 2564407
• DOI: http://doi.org/10.17340/jkna.2024.0055

Abstract

Diagnosing amyotrophic lateral sclerosis (ALS) is challenging and requires distinguishing it from conditions like distal hereditary motor neuropathy type 5 (dHMN-V). A 21-year-old female initially diagnosed with ALS showed progressive upper limb weakness extending to the lower limbs. Trio exome sequencing revealed a de novo pathogenic Berardinelli-Seip congenital lipodystrophy 2 variant (c.263A>G, p.Asn88Ser), confirming dHMN-V. Minipolymyoclonus of small amplitudes in bilateral wrists and ankles was an atypical presentation. This case underscores the importance of considering dHMN-V as a differential diagnosis in ALS-like distal upper extremity weakness.

Keyword

Distal hereditary motor neuropathy; type V; BSCL2; Amyotrophic lateral sclerosis