TITLE:
Course of Atypical Manifestations of a Case of Charcot-Marie-Tooth Disease over 35 Years of Clinical Observation
AUTHORS:
Giuseppe Lanza, Luisa Vinciguerra, Valentina Puglisi, Daniela Modica, Alfio Catalano, Giuseppe Zelante, Riccardo Ricceri, Lorenzo Lupo, Salvatore Giuffrida, Manuela Pennisi
KEYWORDS:
Hereditary Neuropathies; Clinical Overlap; Genetic Analysis; Phenotypic Variability
JOURNAL NAME:
Neuroscience and Medicine,
Vol.4 No.3,
September
10,
2013
ABSTRACT:
Introduction: Atypical manifestations of peripheral
neuropathy are not rare, challenging the differential diagnosis. In the past,
the diagnosis of hereditary neuropathy was mainly based on the clinical and
electromyographic (EMG) findings and, occasionally, biopsy. Nowadays, the
genetic tests allow us to
identify more than 40 different genes/loci associated with Charcot-Marie-Tooth
(CMT) disease, although some subtypes are clinically indistinguishable. We have
followed a patient with a clinical diagnosis of apparent sporadic and atypical CMT
and recently diagnosed genetically as distal hereditary motor neuropathy, type V (dHMN-V). Case Report: Thirty-five years ago, a 16 years old
patient complained muscular weakness and wasting at the hands small muscles.
Sporadic fasciculations were observed whereas deep tendon reflexes and sensation were
normal. EMG examination revealed neurogenic muscular denervation in the distribution of C7, C8 and T1 segments
bilaterally. Muscular biopsy of the left Biceps Brachii showed rare atrophic
fibers and some cellular atypia. The disease has undergone a clinical and EMG
progression and diffusion over the years, involving the lower limbs and leading
to a bilateral steppage. A more slight diffuse axonal motor neuropathy was also
identified in the proband’s son and second cousin. The genetic study found a
known missense mutation in BSCL2 gene
related to a dHMN-V. Interestingly, there was a remarkable intra-familiar
phenotypic variability, especially in the clinical onset and severity. Discussion: Atypical manifestations of hereditary
neuropathies often overlap with other conditions. The present case highlights how a
comprehensive clinical evaluation and a careful follow-up have led to a correct
diagnosis even 35 years later and have allowed to identify other affected
family members. The apparent lack of familiarity was probably due to the very
soft presentation in the proband’s relatives. Although the genetic study was
not available at that time, the first clinical diagnosis was not disavowed. The
main differential diagnoses and a brief review of similar reported cases are
discussed.