ABSTRACT
<p><b>OBJECTIVE</b>To analyze the clinical and pathological features of the centronuclear myopathy (CNM) in 5 Chinese patients and evaluate their diagnostic and differential diagnostic value.</p><p><b>METHODS</b>A standard series of histochemical and enzymohistochemical investigations were performed on all muscle specimens of CNM cases obtained via biopsy. The clinical manifestations and myopathological features of 5 CNM patients were retrospectively analyzed.</p><p><b>RESULTS</b>The age of onset ranged from 3 to 12 years. All patients primarily presented with limb girdle muscle weakness. In 3 patients extraocular muscles, facial muscles and cervical muscles were affected, respectively. The proximal muscles were affected more seriously than the distal and the lower limbs more seriously than the upper. Tendon reflex was reduced and no evident muscular atrophy was seen. The course of the disease ranged from 4 to 46 years and progressed slowly. The ability of walking could be maintained for many years and the fast movements such as running and jumping were impaired early. The serum creatine kinase (CK) level was normal or elevated slightly. Electromyography showed myopathic pattern in all cases. Two patients (mother and son) were from the same family and the son's two siblings had similar symptoms indicating autosomal dominant inherited pattern. There was mild variation in fiber size and most small fibers were round. Interstitial tissue increase slightly. Fibers with centrally placed nuclei accounted for 23% - 93%. Neither necrotic and regenerated fibers nor infiltration of inflammatory cells were seen. Type I fiber predominance and hypotrophy were present in all patients. Abnormal arrangement of the sarcoplasmic strands in appearance of "spokes of a wheel", increased oxidative enzyme activity around centronuclear and perinuclear halo were observed in 2 patients by NADH-TR staining.</p><p><b>CONCLUSIONS</b>For the patients who had the onset during the childhood and presented with slow progressive limb girdle muscle weakness, disability of fast movements and normal serum CK level, the possibility of benign congenital myopathy should be considered. High percentage of centronuclear fibers as well as type I fiber predominance and hypotrophy in muscle biopsy pathology may provide a morphological evidence for the definite diagnosis of CNM.</p>
Subject(s)
Adolescent , Adult , Child , Child, Preschool , Female , Humans , Male , Middle Aged , Biopsy , Creatine Kinase , Blood , Myopathies, Structural, Congenital , Diagnosis , Pathology , Retrospective StudiesABSTRACT
Objective To investigate the clinical,neuroimaging and myopathological features of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes(MELAS).Methods The clinical manifestations,neuroimaging and myopathological features of 31 patients with MELAS diagnosed in our Neuromuscular Center in the recent 7 years were retrospectively analyzed.A3243G point mutations were analyzed by RFLP method in 10 patients.Results ①Clinical features:There were 18 male patients and 13 female patients.The age of onset ranged from 3 to 43 years,averaging 21.9 years.The averaged duration was 4.9 years.Thirteen patients in this group had family history of maternal inheritance pattern.The main clinical manifestations included short stature(26 patients),recurrent headache and vomiting(24 patients), muscle weakness(22 patients),epileptic seizure(21 patients),cognitive decline(19 patients),visual disturbance(17 patients),sensorineural deafness(16 patients),ataxia(6 patients),psychiatric symptom (8 patients),external ophathalmoplegia(2 patients)and diabetes mellitus(9 patients).The serum CK level was slightly elevated in 6 patients,and the fasting blood lactic acid was increased in 15 of the 18 detected patients.②Neuroimaging features:The stroke-like lesions were mostly confined to cerebral cortex, including temporal lobe(24 patients),occipital lobe(21 patients),parietal lobe(12 patients)and frontal lobe(4 patients).Three patients had deep white matter involvement.Migrating stroke-like lesions were confirmed in 4 patients by repeated cranial CT/MRI examination.In addition,cerebral atrophy(17 patients)and bilateral basilar ganglion calcification(11 patients)were found.③Myopathological features: Scattered ragged red fibers(RRF)in various number were found in all the patients by MGT staining.Other founding included strongly SDH-reactive blood vessel(27 patients),COX enzyme deficiency(19 patients), and mild to moderate lipid storage in RRF(20 patients).④MtDNA analysis showed 9 patients with A3243G point mutation in all the detected 13 patients.Conclusion The clinical and neuroimaging features may offer important clue to the diagnosis of MELAS,but a definite diagnosis of MELAS relies on the myopathology and mtDNA mutation analysis.
ABSTRACT
Objective To clarify the clinical features,therapeutic strategy and prognosis of lipid storage myopathy (LSM).Methods The clinical data and therapeutic effects of 42 LSM patients were summarized retrospectively.All patients were followed up to evaluate their prognosis.Results Data of short-term therapeutic results of all the 42 patients were available.Thirty-three cases were placed in low- doses prednisone and 9 cases in riboflavin.All patients showed marked and quick improvement of symptoms within one month.Among thirty-two patients followed up for more than one year,26 cases had a full recovery and 6 remained to have intolerance to heavy exercise.Thirteen patients had relapses of muscle weakness in various degrees and most of which were induced by exertion,exposure to coldness and upper respiratory tract infection.In 5 patients the symptoms were recurred for more than one time.Among 13 cases with relapses, 7 had family history.Conclusions Our data suggest that LSM is a treatable disease and well responsive to low-doses prednisone.The disease tends to recur,especially in patients with family history.Glutaric aciduria type Ⅱ should be considered in LSM patients who are responsive well to riboflavin,indicating drug therapeutic strategy for LSM should be based on the etiology of the disease.