Merosin Deficient Congenital Muscular Dystrophy in Korea

PURPOSES:Congenital muscular dystrophies(CMDs) are an autosomal recessive and heterogeneous disorders. The classic forms of CMD are subclassified into two major categories:merosin positive and deficient. Merosin deficient congenital muscualr dystrophy (MDCMD) is rare in Asia and it has never been reported especially in Korea. So, we summarized the clinical features with neuroimaging findings of the patients, who were diagnosed as MDCMD, for the first time in Korea. METHODS: Twenty three patients were diagnosed as CMD in Seoul National University Children's Hospital over 3 years(2001-2004). Among them, four patients with MDCMD were proven by merosin immunohistochemical staining. We reviewed their clinical, pathologic features, EMG/NCS findings and brain MRIs. RESULTS: Among 23 patients with CMD, 4 patients(17.4%) were MDCMD. All of them were presented at birth or early infancy with hypotonia, muscle weakness and joint contracture. They all could not walk and had myopathic faces, developmental delay, poor weight gain and scoliosis. EMG/NCS showed myopathic motor unit action potential (MUP) and decreased compound motor unit action potential(CMAP). Merosin deficiency was demonstrated in muscle or skin tissues. All of them had diffuse or focal high signal intensity lesions of white matter in brain MR T2WI. However, they showed neither mental retardation nor seizure though one of them had right occipital polymicrogyria. CONCLUSION: We reported 4 children with MDCMD for the first time in Korea. The prevalence in Korea might be lower than in Europe but probably higher than in Japan. If CMD patients have sustained delayed motor milestone with normal intelligence, myopathic face, decreased CMAP and myopathic MUP in EMG/NCS, MDCMD should be suspected and further diagnostic work up such as brain MR and merosin immunohistochemistry will be needed.

MRI findings of primary CNS lymphoma

We retrospectively reviewed magnetic resonance image findings of primary CNS lymphomas in six patients. All patients showed parenchymal masses (n=8), a solitary mass in 4 and multiple in the other two. One patients showed leptomeningeal lesion. Parenchymal masses were located in forntal lobe (n=4), cerebellum (n=2), basal ganglia (n=1), and parietal lobe (n=1), These masses showed hypointensity on T1-weighted images (WI). On T2 WI, the signal intensity of mass was isointense to the brain parenchyma in 5 and hyperintese in 3. After Gadlinium-DTPA injection, seven lesions were enhanced homogeneously, and the margin of the mass was smooth in 5 and irregular in 3. Peritumoral edema was moderate in 4, absent in 3, and severi in 1. These characteristics may be useful in the diagnosis of primary CNS lymphoma.

Prognostic significance of proliferating cell nuclear antigen-positive growth fraction in gastric adenomas

The proliferative activity of gastric adenomas from 18 patients (42 endoscopic procedures) was compared with follow-up results. These cases were gastric adenomas proven by follow-up with repeated endoscopic procedures for more than 2 years, or were confirmed as gastric adenocarcinoma thereafter by histopathologic examination. Among the eighteen cases, nine showed carcinoma in the subsequent biopsies (group 1) and the remaining nine did not result in carcinoma (group 2). The proliferating cell nuclear antigen (PCNA) positivity rates of the two groups were significantly different (P < 0.01). The average PCNA positivity in group 1 was 33.1%, while it was 10.0% in group 2. The risk of developing carcinoma increased as the PCNA positivity increased: 0% in the low PCNA positivity group, 41% in the mid-positivity group and 89% in the high positivity group. We concluded that growth fraction could be taken into account as one of the most important prognostic factors for gastric adenoma, and accordingly repeated endoscopic biopsies with close follow-up should be carried out especially in the high PCNA positivity group.