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Advanced Neurology Rare manifestation in nemaline myopathy

Z disc through its C-terminus, thereby ensuring the A B
structural integrity of the thin filaments. Primarily
3
inherited through autosomal recessive and autosomal
dominant modes, nemaline myopathy typically progresses
slowly and exhibits heterogeneous clinical manifestations.
It is characterized by limb or axial muscle weakness
typically appearing from the neonatal or preschool period,
often accompanied by hypotonia, and involvement of
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facial muscles and joints. Despite the broad spectrum of
clinical phenotypes, the clinical presentation characterized
by pyramidal tract involvement along with oligospermia
has not been reported.
This case report describes a 35-year-old Chinese male
diagnosed with nemaline myopathy, aiming to enrich the Figure 1. The atrophy of the left tongue muscle (A) and the high arches (B)
knowledge regarding its clinical manifestation through the
demonstration of the entire diagnosis process and to avoid biceps and triceps reflexes were symmetrically reduced,
misdiagnosis and missed diagnosis. and his left knee reflex was more active than the right. The
bilateral pectoralis major muscles and deltoids exhibited
2. Case presentation hyperreflexia. The bilateral Hoffmann’s sign, Rossolimo’s
2.1. Medical history and physical examination sign, Babinski’s sign, and Chaddock’s sign were all positive.
A 35-year-old man was admitted to the hospital in April 2.2. Auxiliary examination
2023 due to limb weakness, primarily affecting the lower The patient had a creatine kinase level of 29.0 U/L
limbs, since early childhood, which had worsened over (38 U/L<normal<174 U/L). The sperm concentration was
the past years. His family reported that he experienced 13.63 million/mL (normal ≥20 million/mL). The cephalic
postural instability, weakness in the limbs while learning magnetic resonance imaging yielded normal findings. Due
how to walk, and occasional falls while walking on flat to abnormalities in the pyramidal tract, high arches, and
ground. He also faced difficulty walking up the stairs and oligospermia, an electromyography test was performed.
climbing mountains. The patient required assistive support.
He walked and ran less proficiently than his peers, often The electromyogram showed the shortened duration of the
experiencing fatigue, which was relievable through sufficient motor unit potentials of the bilateral quadriceps femoris
rest. The patient also had delayed motor milestones. Until and right musculus tibialis anterior. The electromyogram
early 2022, the patient experienced a progression in limb also revealed muscle injuries but without neuronal damage,
weakness. He experienced fasciculations in his limbs suggesting that the diagnosis of motor neuron disease
and felt electric numbness in his lower extremities after was incorrect. Given the early symptom onset, sporadic
prolonged sitting. Throughout the course of the disease, late-onset nemaline rode myopathy was very unlikely;
the patient did not experience dizziness, headache, rash, therefore, immunofixation was not conducted.
dyspnea, hoarseness, dysphagia, vomiting, excessive Whole exome sequencing, next-generation sequencing,
sweating, or abnormal breast development. No family and short tandem repeat analyses were performed as genetic
history of hereditary diseases was reported. The patient components of his condition were suspected, in light of
was also sterile due to a low sperm survival index. the symptom appearance since childhood. Subsequently,
For physical examination, he was alert and oriented, his parents and sister were also tested using Sanger
with fluent speech and no signs of dysarthria. The muscle sequencing for result validation. The patient exhibited two
bulk of the whole body decreased significantly, particularly heterozygous variants in the NEB gene: c.21522+3A>G and
on the trapezius and infraspinatus of the right side, with c.23455A>T (Figure 2). His sister also carried these two
a more pronounced reduction in the lower extremities variants. His father carried the c.23455A>T variant, while
compared to the upper extremities. His muscle strength was the c.21522+3A>G variant was not detected. His mother
graded as 5/5, except for the proximal lower extremities, carried the c.21522+3A>G variant but not the other one.
which were graded as 4/5. The extremities exhibited 2.3. Muscle pathology examination
symmetrical hypomyotonia. The bilateral pharyngeal
reflexes were absent. The patient had atrophy of the left The NEB gene is strongly associated with nemaline
tongue muscle and high arches (Figure 1). The bilateral myopathy. Based on the gene sequencing results, we opted

Volume 3 Issue 3 (2024) 2 doi: 10.36922/an.3171