Facial Onset Sensory And Motor Neuronopathy Research Articles

Facial Onset Sensory and Motor Neuronopathy (FOSMN) with C9orf72 Mutation (P5-11.007)

Facial Onset Sensory and Motor Neuronopathy (FOSMN) with C9orf72 Mutation (P5-11.007)

A nationwide survey of facial onset sensory and motor neuronopathy in Japan

The epidemiology and etiology of facial onset sensory and motor neuronopathy (FOSMN), a rare syndrome that initiates with facial sensory disturbances followed by bulbar symptoms, remain unknown. To estimate the prevalence of FOSMN in Japan and establish the characteristics of this disease, we conducted a nationwide epidemiological survey. In the primary survey, we received answers from 604 facilities (49.8%), leading to an estimated number of 35.8 (95% confidential interval: 21.5–50.2) FOSMN cases in Japan. The secondary survey collected detailed clinical and laboratory data from 21 cases. Decreased or absent corneal and pharyngeal reflexes were present in over 85% of the cases. Electrophysiological analyses detected blink reflex test abnormalities in 94.1% of the examined cases. Immunotherapy was administered in 81% of cases and all patients received intravenous immunoglobulin. Among them, 35.3% were judged to have temporary beneficial effects evaluated by the physicians in charge. Immunotherapy tended to be effective in the early stage of disease. The spreading pattern of motor and sensory symptoms differed between cases and the characteristics of the motor-dominant and sensory-dominant cases were distinct. Cases with motor-dominant progression appeared to mimic amyotrophic lateral sclerosis. This is the first nationwide epidemiological survey of FOSMN in Japan. The clinical course of FOSMN is highly variable and motor-dominant cases developed a more severe condition than other types of cases. Because clinical interventions tend to be effective in the early phase of the disease, an early diagnosis is desirable.

Facial Onset Sensory and Motor Neuronopathy with Neurotrophic Keratitis: A Case Report

Facial-onset sensory and motor neuronopathy (FOSMN) is a rare, progressive neurodegenerative disorder characterized by sensory loss and motor deficits, primarily affecting the face and upper extremities. The condition begins with sensory impairments in the trigeminal nerve distribution, extending to involve the scalp, neck, upper limbs, and trunk. Symptoms include facial weakness, bulbar disturbances (dysphonia, dysarthria, dysphagia, and sialorrhea), and lower motor neuron signs (weakness, atrophy, fasciculation, and cramps) in the limbs. A hallmark of FOSMN is the diminished or absent corneal reflex, indicating trigeminal nerve involvement and leading to potential complications like neurotrophic keratitis (NK), which can cause corneal ulceration and blindness. The etiology of FOSMN remains uncertain, with theories proposing autoimmune or neurodegenerative origins. Diagnosis is challenging due to the overlap with other ocular surface disorders, necessitating careful examination and differential diagnosis. Management focuses on symptomatic relief, including eye protection to prevent corneal complications. Awareness and early detection of ocular symptoms in FOSMN are crucial for preventing severe outcomes like NK and blindness.

Facial Onset Sensory and Motor Neuronopathy: A Case Series and Literature Review

Introduction: Facial Onset Sensory and Motor Neuronopathy (FOSMN) typically presents with paresthesias in the trigeminal nerve distribution and weakness that progresses rostro-caudally.
 Objective: To present two new cases of FOSMN, summarize the current literature, and address areas for future study.
 Methods: Observational data was collected from two patients with FOSMN from our institution. A literature review of FOSMN was completed using PubMed.
 Results: We identified 100 cases of FOSMN, including our two new cases. 93% presented with facial paresthesias. 97% had bulbar symptoms. Five had family history of ALS. Abnormal Blink reflex was most common on EMG/NCS. CSF was typically normal, but a rare severe case showed elevated protein. Mutations included: TARDBP, OPMD, D90A-SOD1, CHCHD10, VCP, and SQSTM1. Neuropathological studies showed neurodegenerative changes without inflammation. Some cases have reported transient stabilization or improvement to immunomodulatory therapy.
 Case Reports: A 72-year-old man presented with right-sided trigeminal paresthesias that progressed in a rostro-caudal fashion, dysphagia, and hand weakness. He died 4-5 years after symptom onset. A 69-year-old man presented with left-sided jaw paresthesias, dysphagia and dysarthria. He was trialed on IVIG for 1.5 years without improvement and died 2.6 years after symptom onset.
 Conclusion: FOSMN is a rare disorder with a unique clinical and electrophysiological phenotype. The pathophysiology has been associated with neurodegeneration and multiple gene mutations have correlated to FOSMN. Some reports suggest transient response to immunomodulatory therapy, though prospective studies are lacking. CSF protein elevation may be seen in severe disease. Future studies will help further elucidate the approach to diagnosis, treatment, and prognostic counseling (biomarkers).

Muscle and skin fibroblast TDP-43 expression, dynamic mutation analysis of NOTCH2NLC and C9orf72 in patients with FOSMN.

Facial-onset sensory and motor neuronopathy (FOSMN) syndrome is a rare clinical syndrome in which the etiopathogenesis and disease-causing genes remain unknown. In addition, clinical and molecular pathological studies have rarely been evaluated in a large case series. In this study, we present the clinical features and electrodiagnostic findings of the largest cohort of six patients with FOSMN in East Asia to date. Immunofluorescence assessment of TAR DNA-binding protein (TDP)-43 in muscle and skin fibroblasts, detection of GGC trinucleotide repeat expansions in NOTCH2NLC gene, and GGGGCC hexanucleotide repeat expansions in the C9orf72 gene were also performed. All patients exhibited typical symptoms and signs of FOSMN syndrome. Almost all patients showed a delayed or absent blink reflex. Neurogenic damage was found in five patients by electromyography. Two of the five patients with muscle and skin biopsies showed TDP-43-positive inclusions in both the nucleus and cytoplasm of muscular tissue and skin fibroblasts. There were no repeat expansions in the C9orf72 or NOTCH2NLC genes in any of the six patients. To date, this is the largest FOSMN cohort in East Asia. TDP-43-positive cytoplasmic inclusions in muscle and skin fibroblasts may be a pathologic feature of the disease. The patient's dynamic mutation test showed no GGC trinucleotide repeat expansions in the NOTCH2NLC and GGGGCC hexanucleotide repeat expansions in the C9orf72 gene. Further studies are needed with more patients.

Nuclear countdown

Case: A 50-year-old woman presented with a 10-year history of progressive symptoms, beginning with right facial numbness. She developed dysgeusia, and dysphagia before the onset of dysarthria. She had progressive gait instability with frequent backwards falls. A gastrostomy was inserted for persistent weight loss. She required hospital admission for aspiration pneumonia and type 2 respiratory failure. On examina- tion she had a head drop and staring expression with reduced blink frequency and hypophonia. There was bilateral facial weakness with temporalis and tongue wasting. She had a supranuclear gaze palsy and her saccadic eye movements were almost absent in all directions. Limbs were hypotonic with distal weakness and reduced reflexes.InvestigationsNCS/EMG showed chronic widespread partial denervation in the facial, trigeminal (motor) and hypoglossal-innervated muscles. Blink reflexes were absent bilaterally. There were chronic denerva- tion changes in the cervical and lumbar spinal segments. MRI brain showed global atrophy particularly implicating the temporal lobes and brainstem.DiagnosisA diagnosis of Facial-Onset Sensory and Motor Neuronopathy (FOSMN) was made. Given the additional clinical features of supranuclear gaze palsy we believe this is the first case of FOSMN-PSP overlap syndrome.ConclusionWe report a unique FOSMN case with some overlap features of PSP, not previously described. daniel.rice-wilson@nhs.net23

Facial Onset Sensory and Motor Neuronopathy: New Cases, Cognitive Changes, and Pathophysiology.

Purpose of ReviewTo improve our clinical understanding of facial onset sensory and motor neuronopathy (FOSMN).Recent FindingsWe identified 29 new cases and 71 literature cases, resulting in a cohort of 100 patients with FOSMN. During follow-up, cognitive and behavioral changes became apparent in 8 patients, suggesting that changes within the spectrum of frontotemporal dementia (FTD) are a part of the natural history of FOSMN. Another new finding was chorea, seen in 6 cases. Despite reports of autoantibodies, there is no consistent evidence to suggest an autoimmune pathogenesis. Four of 6 autopsies had TAR DNA-binding protein (TDP) 43 pathology. Seven cases had genetic mutations associated with neurodegenerative diseases.SummaryFOSMN is a rare disease with a highly characteristic onset and pattern of disease progression involving initial sensory disturbances, followed by bulbar weakness with a cranial to caudal spread of pathology. Although not conclusive, the balance of evidence suggests that FOSMN is most likely to be a TDP-43 proteinopathy within the amyotrophic lateral sclerosis–FTD spectrum.

Taste disorder in facial onset sensory and motor neuronopathy: a case report

BackgroundTaste disorder is a common symptom in the general population. Several studies have shown that patients with neurological disorders, such as amyotrophic lateral sclerosis and Parkinson’s disease, develop taste disturbance. Facial onset sensory and motor neuronopathy (FOSMN) is a rare disease characterized by sensory disturbance and weakness spreading from the face to the limbs caudally. We describe a patient with FOSMN who showed taste disorder as the sole initial symptom.Case presentationA 49-year-old man who smoked cigarettes developed taste disturbance. Despite using zinc supplements, an herbal medication, and an ointment, his taste disorder worsened. 4 years later, a tingling feeling emerged at the tip of his tongue and gradually spread to his entire lips. At 55 years of age, he showed difficulty in swallowing, followed by facial paresthesia, muscle atrophy, and weakness in the face and upper limbs without apparent upper motor neuron sign. Cessation of smoking did not improve his taste disturbance, and he was unable to discriminate different tastes on the entire tongue. In an electrogustometric study, electrical stimulation did not induce any type of taste sensation. Blink reflex showed delayed or diminished R2 responses. Needle electromyography revealed severe chronic neurogenic changes in the tongue and masseter muscles. Mild chronic neurogenic changes were also observed in the limbs. In the thoracic paraspinal muscles, active neurogenic changes were detected. Findings of hematological and cerebrospinal fluid analyses, and magnetic resonance images of the brain and spinal cord were unremarkable. One cycle of intravenous immunoglobulin therapy did not improve his symptoms. We diagnosed him as having FOSMN with the sole initial symptom of taste disorder. Nine years after the onset of taste disorder, he developed impaired sensation of touch in the right upper limb and required tube feeding and ventilator support.ConclusionTaste disorder can be the initial manifestation of FOSMN and might involve the solitary nucleus.

Facial onset sensory and motor neuronopathy: a motor neuron disease with an oligogenic origin?

Objective: To describe a patient with facial onset sensory and motor neuronopathy (FOSMN) carrying heterozygous mutations in both TARDBP and SQSTM1 genes. Methods: The patient underwent neurological, neuropsychological, and neurophysiological examinations. Brain magnetic resonance imaging (MRI) and extensive genetic analysis were also performed. Results: The neurological examination showed dysphonia, left trigeminal hypesthesia, and left masseter and temporalis muscle atrophy. Mild cognitive impairment, affecting predominantly executive functions and social cognition, was appreciable in the neuropsychological examination. The electrophysiological studies revealed: left abnormal blink reflex; neurogenic changes in bulbar and cervical muscles; normal motor evoked potential amplitude, central motor conduction time and cortical silent period. Brain MRI showed right-predominant frontotemporal atrophy. Genetic analysis showed a heterozygous mutation in TARDBP (p.A390S) and in SQSTM1 (p.P392L), both previously described as causing amyotrophic lateral sclerosis. The SQSTM1, but not the TARDBP, mutation was found in both healthy siblings. Conclusions: Our data provide new clinical, neuroimaging, and genetic evidence that FOSMN is a neurodegenerative disease of the motor neuron disease and frontotemporal dementia spectrum, with a possible oligogenic origin. Multicentric efforts focusing on cognitive and genetic studies are necessary to confirm this hypothesis and to determine if ALS genes should be systematically screened in these patients.

New findings in facial-onset sensory and motor neuronopathy (FOSMN) syndrome

Facial-onset sensory and motor neuronopathy (FOSMN) syndrome represents a rare, slowly progressive, lower motor neuron disease with sensory compromise, involving mainly the face, bulbar region and upper limbs. However, non-motor symptoms and neurogenetic studies have rarely been evaluated in large case series. In the present study, 10 unrelated Brazilian patients with FOSMN syndrome underwent extensive clinical, laboratory, neurophysiological and neurogenetic assessment. Median age at symptom onset was 52.1 years, and men and women were equally affected. Patients presented with hemifacial or bilateral facial paresthesia and weakness, which evolved with dysphagia, dysphonia, and facial and tongue atrophy and, finally, a dropped-head, upper limb weakness and syringomyelia-like sensory disturbances in the upper limbs. All 10 patients showed chronic diffuse neurogenic compromise of bulbar, cervical and thoracic myotomes, and abnormal blink reflex tests. A positive family history of neurodegeneration was identified in six cases, and revealed pathogenic gene variants in three families (involving VCP, TARDBP and CHCHD10). Thus, our case series has revealed new findings regarding FOSMN syndrome: (i) its clinical course is not always benign, with poorer prognoses associated with dropped-head syndrome and early bulbar compromise; (ii) FOSMN syndrome may be part of a complex familial neurodegenerative spectrum; and (iii) a definite genetic basis may be observed in some cases.

Facial onset sensory and motor neuronopathy.

Facial onset sensory and motor neuronopathy (FOSMN) is a recently defined slowly progressive motor neuron disorder. It is characterized by facial onset sensory abnormalities which may spread to the scalp, neck, upper trunk and extremities, followed by lower motor neuron deficits. Bulbar symptoms, such as dysarthria and dysphagia, muscle weakness, cramps and fasciculations, can present later in the course of the disease. We search the PubMed database for articles published in English from 2006 to 2016 using the term of "Facial onset sensory and motor neuronopathy". Reference lists of the identified articles were selected and reviewed. Only 38 cases of FOSMN have been reported in the Pubmed database since it was first reported in 2006. Typically, FOSMN present with slowly evolving numbness of the face followed by neck and arm weakness. Reduced or absent of corneal reflexes and blink reflex is the main pathognomonic features of FOSMN. In this review, we summarize the epidemiology, clinical presentation, auxiliary examination, and treatment of all the reported cases of FOSMN. Moreover, we discuss the pathogenesis of this rare disorder. In addition, we propose diagnostic criteria for FOSMN.

Amyotrophic lateral sclerosis causes small fiber pathology.

Our aim was to address the correlation between small fiber loss and amyotrophic lateral sclerosis (ALS) for disease onset, phenotype, genotype, duration, severity and sensory findings. Consecutive patients referred for suspected ALS were screened. Exclusion criteria were possible ALS and previous diagnosis or known risk factors for small fiber neuropathies. A sural nerve conduction study (NCS) was bilaterally recorded. The ALS functional rating scale revised was administered and loss of functions were calculated using the Milano-Torino staging (MITOS) system. Sensory symptoms and signs were recorded. Genetic analysis was performed by the next-generation sequencing approach. Skin biopsy was performed at the distal leg and intraepidermal nerve fiber (IENF) density was quantified in three non-consecutive sections following published guidelines. Findings were referred to age- and sex-adjusted normative values. Fifty-seven patients including six with facial onset sensory and motor neuronopathy (FOSMN) were enrolled. Eight (15.7%) pure ALS patients and five (83%) FOSMN patients complained of sensory disturbances with different distributions. Sural NCS was normal in all except two patients. IENF density was reduced in 75.4% of pure ALS and 50% of FOSMN patients, without correlation with any disease features. IENF density was similarly reduced in bulbar (78.5%), flail limb (87.5%), pyramidal (100%), and spinal (68.2%) onset, as well as in genetic (83.3%) and sporadic (82%) ALS. There was no correlation with genotype, disease duration and severity. Intraepidermal nerve fiber loss is a feature of most ALS patients. It does not correlate with onset, phenotype, course and severity of the disease, and cannot be considered a clinical or prognostic biomarker.

Recognising facial onset sensory motor neuronopathy syndrome: insight from six new cases

Facial onset sensory and motor neuronopathy (FOSMN) was first described in 2006 as an apparently sporadic neurodegenerative disease. Thirty cases have been reported to date. We summarise six new cases,...

Corneal confocal microscopy reveals trigeminal small sensory fiber neuropathy in amyotrophic lateral sclerosis

Although subclinical involvement of sensory neurons in amyotrophic lateral sclerosis (ALS) has been previously demonstrated, corneal small fiber sensory neuropathy has not been reported to-date. We examined a group of sporadic ALS patients with corneal confocal microscopy, a recently developed imaging technique allowing in vivo observation of corneal small sensory fibers. Corneal confocal microscopy (CCM) examination revealed a reduction of corneal small fiber sensory nerve number and branching in ALS patients. Quantitative analysis demonstrated an increase in tortuosity and reduction in length and fractal dimension of ALS patients’ corneal nerve fibers compared to age-matched controls. Moreover, bulbar function disability scores were significantly related to measures of corneal nerve fibers anatomical damage. Our study demonstrates for the first time a corneal small fiber sensory neuropathy in ALS patients. This finding further suggests a link between sporadic ALS and facial-onset sensory and motor neuronopathy (FOSMN) syndrome, a rare condition characterized by early sensory symptoms (with trigeminal nerve distribution), followed by wasting and weakness of bulbar and upper limb muscles. In addition, the finding supports a model of neurodegeneration in ALS as a focally advancing process.

TAR DNA-binding protein 43 pathology in a case clinically diagnosed with facial-onset sensory and motor neuronopathy syndrome: An autopsied case report and a review of the literature

We report an autopsy case of a 48-year-old female clinically diagnosed with facial-onset sensory and motor neuronopathy (FOSMN) syndrome with TAR DNA-binding protein 43 (TDP-43) pathology. She developed paresthesia involving her whole face, right upper extremity and the right side of her upper trunk, followed by dysphagia, dysarthria, muscle atrophy and weakness with fasciculation in both upper extremities. Her symptoms showed a marked cranial and right-sided dominancy. She had anti-sulfoglucuronyl paragloboside (SGPG) IgG and anti-myelin-associated glycoprotein (MAG) IgG, and repeatedly showed limited response to immunotherapies. Her disease was essentially progressive, culminating in death due to respiratory failure three and a half years after onset. The autopsy revealed severe degeneration of the nuclei of the right trigeminal nerve and right facial nerve and widespread TDP-43-positive glial inclusions in the brainstem tegmentum. Neurons in the hypoglossal nerve nuclei were also shrunken and lost, with TDP-43-positive neuronal inclusions. Neuronal loss and gliosis in the anterior horn, predominantly in the cervical cord, were prominent with TDP-43-positive skein-like inclusions. Bilateral ventral roots were obviously atrophic. Spinal tract degeneration was also prominent in the ventral columns, essentially sparing the anterior corticospinal tracts at the cervical cord level. Additionally there was severe myelin pallor in the right spinal trigeminal tract and right fasciculus cuneatus of the cervical cord. The right spinal root ganglion showed numerous Nageotte's nodules and focal lymphocytic infiltration. The present case manifested FOSMN syndrome clinically, while the pathological findings suggested a motor neuron disease like TDP-43 proteinopathy and a possible involvement of immune-mediated neuropathy.

FOSMN syndrome

To better define the pathophysiologic mechanisms underlying the development of the novel facial-onset sensory and motor neuronopathy (FOSMN) syndrome and, in particular, to determine whether neurodegenerative processes, mediated by excitotoxicity, or autoimmune mechanisms contribute to the development of FOSMN syndrome. Clinical, laboratory, neurophysiologic, and pathologic assessments were undertaken for 5 patients with FOSMN syndrome (3 male and 2 female), the largest cohort of FOSMN syndrome reported to date. In addition to conventional neurophysiologic studies, novel threshold tracking transcranial magnetic stimulation (TMS) techniques were undertaken to assess for the presence of cortical excitability. Clinically, all patients exhibited the typical FOSMN syndrome phenotype, heralded by facial-onset sensory deficits with subsequent development of motor deficits evolving in a rostral-caudal direction. Pathologic studies, including an autopsy, disclosed widespread degeneration of sensory and motor neurons with no evidence of inflammation, amyloid deposition, or intraneuronal inclusions, such as TDP-43, Bunina bodies, or ubiquitin inclusions. Conventional neurophysiologic studies revealed abnormalities of blink reflexes, along with features of motor and sensory neuronopathy. Threshold tracking TMS disclosed normal cortical excitability in patients with FOSMN syndrome, with preserved short-interval intracortical inhibition, resting motor threshold, motor evoked potential amplitude, and cortical silent period duration. Patients with FOSMN syndrome failed to respond to immunomodulatory approaches. Findings from the present study suggest that FOSMN syndrome is a primary neurodegenerative disorder of sensory and motor neurons, with distinct pathophysiologic mechanisms.

174 Horizontal saccade slowing in a patient with facial onset sensory and motor neuronopathy (FOSMN)

FOSMN is heralded by facial sensory loss with subsequent sensory and motor loss spreading caudally. Few cases have been described in the literature but a single case with upper motor...

Clinical features and follow‐up of four new cases of facial‐onset sensory and motor neuronopathy

In this study we report three patients with facial-onset sensory and motor neuronopathy (FOSMN), including the first female to be described. A fourth rather atypical case of a pyramidal syndrome with a fast rate of progression is also described. These cases raise the question as to whether upper motor neuron impairment is involved in FOSMN and whether there is a link between this syndrome and amyotrophic lateral sclerosis. The existence of this syndrome suggests that it may be wise to monitor all patients with isolated idiopathic trigeminal sensory neuropathy to ensure that this type of motor neuron disease is not overlooked.

Facial onset sensory and motor neuronopathy (FOSMN) syndrome responding to immunotherapies

We report the first non-Caucasian case of facial onset sensory and motor neuronopathy (FOSMN) syndrome partially responding to various immunotherapies. A 55-year-old man had first felt paresthesia on his right cheek at age 45. This gradually extended to the scalp. Paresthesia of bilateral fingers and dysphagia appeared 6 years later. On admission, facial sensory impairment and bulbar palsy were found. There were no sensory or motor deficits evident in any limb, except for decreased deep tendon reflex and vibratory sensation. Videofluorography (VF) revealed decreased pharyngeal clearance. The sensory nerve action potential (SNAP) amplitudes of median and ulnar nerves were decreased. Intravenous immunoglobulin therapy and plasma exchange ameliorated his dysesthesia and dysphagia after several weeks, and resulted in improvements in VF and SNAP abnormalities. These observations suggest that FOSMN syndrome maybe, in part, immune-mediated.

Anchorage and attachment

Motor neuron disease (MND) represents a wide and heterogeneous expanding group of disorders involving the upper or lower motor neurons, mainly represented by amyotrophic lateral sclerosis (ALS), primary lateral sclerosis, progressive muscular atrophy and progressive bulbar palsy. Primary motor neuronopathies are characterized by progressive degenerative loss of anterior horn cell motoneurons (lower motor neurons) or loss of giant pyramidal Betz cells (upper motor neurons). Despite its well-known natural history, pathophysiological and clinical characteristics for the most common MND, atypical clinical presentation and neurodegenerative mechanisms are commonly observed in rare clinical entities, so-called atypical variants of MND-ALS, including flail-leg syndrome, flail-arm syndrome, facial-onset sensory and motor neuronopathy (FOSMN), finger extension weakness and downbeat nystagmus (FEWDON-MND) and long-lasting and juvenile MND-ALS. Herein, we provide a review article presenting clinical, genetic, pathophysiological and neuroimaging findings of atypical variants of MND-ALS in clinical practice.