Clinical Characteristics and Molecular Genetic Analysis of Korean Patients with GNE Myopathy

PURPOSE: Glucosamine (UDP-N-acetyl)-2-epimerase/N-acetylmannosamine kinase (GNE) myopathy is an autosomal recessive neuromuscular disorder characterized by early adult-onset weakness of the distal muscles of the lower limbs. The clinical spectrum of GNE myopathy varies, and it is not clear how the same GNE gene mutations can result in different phenotypes. Here, we present clinical, pathological and genetic characteristics of twenty-one Korean patients with GNE myopathy. MATERIALS AND METHODS: Twenty-one GNE myopathy patients were included in this study, conducted from 2004 to 2011. Based on medical records, patients' gender, onset age, family history, clinical history, serum creatine kinase (CK) level, neurologic examination, findings of muscle biopsy, muscle imaging findings and electrophysiologic features were extensively reviewed. Mutation of the GNE gene (9p13.3) was confirmed by DNA direct sequencing analysis in all patients. RESULTS: The mean onset age was 23.8+/-8.8 years (mean+/-SD). Patient serum CK levels were slightly to moderately elevated, ranging from 41 to 2610 IU. Among the patients, twelve patients were female and nine patients were male. Except for eight patients, all of the patients presented initially with only distal muscle weakness in the lower extremities. The most common mutation was V572L, followed by C13S. CONCLUSION: The clinical manifestations of our patients with GNE mutations varied. Among twenty-one patients, thirteen patients showed the typical GNE myopathy phenotype. There was no relationship between clinical features and site of mutation. Therefore, we suggest that neither homozygous nor compound heterozygous models are correlated with disease phenotype or disease severity.

A Case of GNE Myopathy Presenting a Rapid Deterioration during Pregnancy

BACKGROUND: GNE myopathy is characterized by early-adult-onset distal myopathy sparing quadriceps caused by mutations in the GNE gene encoding UDP-N-acetylglucosamine 2-epimerase/N-acetylmannosamine kinase, an enzyme in the sialic-acid synthesis pathway. CASE REPORT: A 27-year-old Korean woman presented a rapid deterioration in strength of the distal lower limbs during her first pregnancy. She was diagnosed with GNE myopathy and carrying the compound heterozygous mutations of the GNE gene (D208N/M29T). CONCLUSIONS: This is a representative case implying that an increased requirement of sialic acid during pregnancy might trigger a clinical worsening of GNE myopathy.

A Case of Acute Disseminated Encephalomyelitis Associated with Hepatitis C Virus Infection

Acute disseminated encephalomyelitis (ADEM) is a monophasic autoimmune demyelinating disease of the central nervous system, which typically follows acute viral or bacterial infection or vaccination. We report a case of ADEM associated with hepatitis C virus (HCV) infection with positive serum and cerebrospinal fluid (CSF) anti-HCV antibody. After steroid treatment, neurologic symptoms were improved. Virus triggers autoimmunity or direct viral invasion plays a part in the genesis of ADEM. This is the first reported case of ADEM with anti-HCV antibody in the CSF.

Facial Diplegia in Plasmodium vivax Malaria

BACKGROUND: Facial diplegia has diverse etiologies, including viral and bacterial infections such as diphtheria, syphilis and Lyme disease, and also protozoal infection in very rarely cases. CASE REPORT: A 20-year-old male patient was admitted to our hospital due to bilateral weakness of the upper and lower facial muscles. Examination revealed that the patient had a facial diplegia of the peripheral type. A peripheral blood smear demonstrated the presence of the asexual trophozoite stage of Plasmodium vivax with ring-form trophozoites, which led to a diagnosis of malaria. A serum work-up revealed increased IgG titers of antibodies to myelin-associated glycoprotein and ganglioside GD1b. The patient was administered antimalarial treatment, 1 week after which he showed signs of recovery. To our knowledge, this is the first case of facial diplegia after malaria infection, providing evidence that the mechanism underlying the condition is related to immune-mediated disease. CONCLUSIONS: Facial diplegia can manifest after P. vivax infection.

Clinical Features of the Patients with Seizures after Doxylamine Succinate Overdose / 대한간질학회지

PURPOSE: Doxylamine succinate is an over-the-counter drug commonly used in the treatment of insomnia. It is in the ethanolamine class of antihistamine and is frequently involved in intentional overdoses. Seizures are uncommon, but there are potentially serious complications, making early recognition and treatment essential. METHODS: We reviewed retrospectively the medical records of patients admitted for seizures after a doxylamine succinate overdose from Jan. 1, 1992 to Dec. 31, 2008. We evaluated them with respect to age, sex, amount ingested, clinical symptomatology, time from ingestion to seizure, complication, and prognosis. RESULTS: Among the 146 doxylamine overdose patients, 11 patients developed seizures. Females accounted for 9 (81.8%) patients and the number aged between 20 and 40 years was also 9 cases (81.8%). The average time from ingestion to emergency room visit was 170 minutes (60-360). The average time from ingestion to development of seizures was 188 minutes (60-480). The amount of doxylamine succinate ingested was 750-4,750 mg (mean = 2,425 mg). The frequent anticholinergic symptoms were tachycardia (63.6%), vomiting (45.5%), mydriasis (36.4%), and hypertension (36.4%). Rhabdomyolysis and drug induced hepatitis were observed in 7 cases (63.6%) and 6 cases (54.5%), respectively. Primary treatment included administration of benzodiazepine and conservative care. After more than a 6 month follow-up, no patients developed further seizure. CONCLUSIONS: The incidence of seizure after doxylamine succinate overdose is uncommon and prognosis is good. However, other serious symptoms are commonly combined, and we have to be aware that seizures are a potential complication and should be actively investigated and vigorously treated.