Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0013421 (dystonia)
 8,418 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report on three patients with xeroderma pigmentosum group A (XPA) who showed laryngeal stridor in their 20s. The stridor appeared on feeding and emotional excitation, was exaggerated during respiratory infection and was life-threatening on some occasions. Adduction of the vocal cords during inspiration, observed by laryngoscopy, confirmed laryngeal dystonia in all cases. This type of focal dystonia may be characteristic in XPA and requires special attention during the management of these patients to avoid serious complications.
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PMID:Laryngeal dystonia in xeroderma pigmentosum. 1592 64

We have prospectively followed 16 Finnish xeroderma pigmentosum (XP) patients for up to 23 years. Seven patients were assigned by complementation analysis to the group XP-A, two patients to the XP-C group and one patient to the XP-G group. Six of the seven XP-A patients had the identical mutation (Arg228Ter) and the seventh patient had a different mutation (G283A). Further patients were assigned to complementation groups on the basis of their consanguinity to an XP patient with a known complementation group. The first sign of the disease in all the cases was severe sunburn with minimal sun exposure in early infancy. However, at the time the diagnosis was made in only two cases. The XP-A patients developed neurological and cognitive dysfunction in childhood. The neurological disease advanced in an orderly fashion through its successive stages, finally affecting the whole nervous system and leading to death before the age of 40 years. Dermatological and ocular damage of the XP-A patients tended to be limited. The two XP-C patients were neurologically and cognitively intact despite mild brain atrophy as seen by neuroimaging. The XP-G patients had sensorineural hearing loss, laryngeal dystonia and peripheral neuropathy. The XP-C patients had severe skin and ocular malignancies that first presented at pre-school age. They also showed immunosuppression in cell-mediated immunity. Neurological disease appears to be associated with the complementation group and the failure of fibroblasts to recover RNA synthesis following UV irradiation, but not necessarily to the severity of the dermatological symptoms, the hypersensitivity of fibroblasts to UVB killing or the susceptibility of keratinocytes to UVB-induced apoptosis.
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PMID:Neurological symptoms and natural course of xeroderma pigmentosum. 1866 91

This article deals with the neurological basis of brainstem-related symptoms in disabled children. Synaptic interactions of respiratory and swallowing centers, which are briefly reviewed in this study, highlight the significance of the nucleus of solitary tract (NTS) in the stereotyped motor events. Coordination mechanisms between these two central pattern generators are also studied with a focus on the inhibitory action of decrementing expiratory neurons that terminate the inspiratory activity and become activated during swallowing. Dorsal brainstem lesions in hypoxic-ischemic encephalopathy (HIE) affect the area including NTS, and result in symptoms of apneusis, facial nerve paresis, dysphagia, gastroesophageal reflux, and laryngeal stridor. Leigh syndrome patients with similar distributions of medullary lesions show increased sighs, post-sigh apnea, hiccups, and vomiting in addition to the symptoms of HIE, suggesting pathologically augmented vagal reflex pathways. The present article also discusses the pathophysiology of laryngeal dystonia in xeroderma pigmentosum group A, self-mutilation in Lesch-Nyhan syndrome, and sudden unexpected death in Fukuyama congenital muscular dystrophy. Close observation and logical assessment of brainstem dysfunction symptoms should be encouraged in order to achieve better understanding and management of these symptoms in disabled children.
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PMID:Reflections on the brainstem dysfunction in neurologically disabled children. 1932 67

Xeroderma pigmentosum (XP), a genetic disorder in DNA nucleotide excision repair, is characterized by skin hypersensitivity to sunlight and progressive neurological impairment. Laryngeal dystonia and vocal cord paralysis are complications that can arise in older XP group A (XPA) patients. We report three patients with XPA being administered low-dose levodopa (0.3-1.5 mg/kg/day) for laryngeal dystonia. Patients were aged from 13 to 18 years, exhibited paroxysmal choking and inspiratory stridor, and were diagnosed with laryngeal dystonia. Two XPA patients responded to low-dose levodopa, and paroxysmal choking and involuntary movements resolved, although one of the two patients showed incomplete resolution due to suspected vocal cord paralysis. The other patient was unable to tolerate the medication because of a transient decrease of muscle tone in the extremities. We previously reported a decreased immunostaining of dopaminergic (DA) terminals in the basal ganglia of XPA patients, which may be involved in laryngeal dystonia. Low-dose levodopa has been reported to alleviate DA receptor supersensitivity in tic patients, while laryngeal dystonia occurs in patients with tardive dyskinesia caused by DA receptor supersensitivity. Thus, low-dose levodopa may improve laryngeal dystonia by alleviating DA receptor supersensitivity in XPA patients. We recommend that low-dose levodopa be used for treatment of paroxysmal respiratory disturbances and/or involuntary movements in XPA patients.
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PMID:Low-dose levodopa is effective for laryngeal dystonia in xeroderma pigmentosum group A. 1981 90

Xeroderma pigmentosum (XP) is an uncommon inherited dermatological disorder characterized by a high degree of skin photosensitivity with development of carcinomas at an early age. Neurological manifestations may be encountered in XP but few detailed descriptions have been provided. Here we describe a sister and a brother presenting chorea, dystonia, myoclonus, ataxia and polyneuropathy related to XP.
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PMID:Xeroderma pigmentosum: a rare cause of chorea. 2151 43