Clinical sequelae of 17 cases with glycogen storage disease type II/Pompe disease / 中华儿科杂志

<p><b>OBJECTIVE</b>To analyze and summarize the characteristics of glycogen storage disease type II (Pompe disease) patients according to the clinical description and prognosis.</p><p><b>METHOD</b>Seventeen Chinese patients diagnosed by acid alpha-glucosidase (GAA) enzyme activity test were reviewed. Clinical data tables were designed. Interviews were made via phone calls. Information was collected to reach the objective.</p><p><b>RESULT</b>Four of 17 patients diagnosed by acid alpha-glucosidase are infantile-onset, symptoms started between 2 to 6 months after birth with increased serum creatine kinase and cardiac problems, with or without respiratory concerns. Other 13 patients were later-onset cases, and their symptoms started between 2 to 22 years of age with increased serum creatine kinase. Eleven later-onset patients started with muscle weakness, 2 patients developed respiratory insufficiency, 2 patients showed scoliosis, and 1 patient expressed increased serum creatine kinase with abnormal liver function. Just 3 of the later-onset patients were treated with mechanical ventilator and adjuvant therapy, others were not. All patients' acid alpha-glucosidase (GAA) enzyme activity analysis showed lower than 10% of normal. Fourteen patients were tested by muscle biopsy pathology, and 9 of them progressed to glycogen storage disease type II; 10 patients received genetic analysis, and 6 of them had two mutations which cause the disorder. Twelve of the 17 patients were interviewed successfully. In 3 of the infant-onset patients the disease resulted in death from respiratory failure, and 1 is still alive at the age of 1 year and 7 months. In 4 of 8 later-onset patients the disease resulted in death from respiratory failure between 3 to 5 years after onset of symptoms. Three of 4 survivors had increased muscle weakness, and 1 patient kept alive with ventilator without any changes. Seven of 12 interviewed patients died, the mortality rate was 58.3%.</p><p><b>CONCLUSION</b>Glycogen storage disease type II (Pompe disease) present differently in the clinic. Infant-onset Pompe disease is mainly characterized by generalized muscle weakness and obvious cardiac involvement. It's a dangerous disease, with high mortality rate. Later-onset Pompe disease is characterized by chronic proximal muscle weakness and respiratory insufficiency. GAA enzyme activity analysis, muscle biopsy and genetic analysis used to support the diagnosis of Pompe disease. Prognosis of the disease depends on age of onset and respiratory muscle involvement.</p>

Mutation in the SLC37A4 gene of glycogen storage disease type Ib in 15 families of the mainland of China / 中华儿科杂志

<p><b>OBJECTIVE</b>Glycogen storage disease type Ib (GSDIb, MIM: 232220) is an autosomal recessive inborn error of metabolism caused by deficiency of the glucose-6-phosphate translocase. The clinical manifestations include symptoms and signs of both the typical GSDIa, including hepatomegaly, fasting hypoglycemia, lactic acidemia and hyperlipidemia, and the dysfunction of neutrophils of recurrent infection and neutropenia. More than 84 mutations have been identified since the discovery of the SLC37A4 gene as the disease causing gene. Up to date, 5 mutations in 4 Chinese patients were reported from Hong Kang and Taiwan. In order to see the spectrum of the SLC37A4 gene mutations and the correlation between genotype and phenotype in patients with GSDIb of the mainland of China, the authors investigated 17 GSDIb patients from 15 families in this study.</p><p><b>METHOD</b>Data of 17 patients from 12 provinces, 11 male and 6 female, aged 6 months to 35 years, were collected from the genetic clinics of Peking Union Medical College Hospital from Oct. 2006 to Mar. 2009. All of them were Han Chinese in ethnicity. Consanguineous status was confirmed in 2 unrelated patients. All patients were presented with hepatomegaly, fasting hypoglycemia, lactic acidemia, hyperlipidemia and neutropenia with variable frequency of infections. The full coding exons, their relevant exon-intron boundaries, and the 5'- and 3'-flanking regions of the SLC37A4 gene were amplified and directly sequenced. RT-PCR was performed to verify the effect of the 2 novel splicing mutations.</p><p><b>RESULT</b>A total of 11 mutations were identified in 15 families. Four mutations, p.Gly149Glu, p.Pro191Leu, p.Arg415X and c.1042_1043 del CT, were previously reported, and seven mutations, p. Leu23Arg, p.Gly115Arg, p.Gly281Val, p.Arg415Gly, c.784 + 1G > A, c.870 + 5G > A and c.1014_1120del107, were novel. The frequent mutations are p.Pro191Leu, p.Gly149Glu and c.870 + 5G > A, accounting for 37%, 15% and 11% of mutant alleles respectively. RT-PCR analysis of novel mutation c.784 + 1G > A confirmed the splicing of exon 5 of 159 bp, causing inframe deletion. While mutation c.870 + 5G > A was proved to cause exon 6, 86 bp, deletion causing frame-shift. Among 15 families, 12 genotypes were identified, including 3 with homozygous mutation and 9 with compound heterozygous mutations. Homozygous p.Pro191Leu mutation was the only genotype detected in more than 1 family and was found in 4 unrelated families, including 1 patient from consanguineous marriage.</p><p><b>CONCLUSION</b>A total of 11 SLC37A4 gene mutations were identified in 15 families of the mainland of China. The frequent mutations are p.Pro191Leu, p.Gly149Glu and c.870 + 5G > A. The number of Chinese SLC37A4 gene mutations was extended from 5 to 14.</p>

Clinical characteristics and follow-up of 12 cases with severe chronic active Epstein-Barr virus infection / 中华儿科杂志

<p><b>OBJECTIVE</b>There are two different types of chronic active Epstein-Barr virus (CAEBV) infection: chronic EBV (CEBV) having persistent infectious mononucleosis (IM)-like illness with relatively good prognosis, and severe CAEBV (SCAEBV)infection that has rather severe manifestations and generally poor prognosis with many life-threatening complications, such as EBV-associated malignant lymphoma and hemophagocytic syndrome (HPS). The purpose of this study was to clarify the clinical and prognostic characteristics in 12 cases with SCAEBV infection.</p><p><b>METHOD</b>Data of 12 cases with SCAEBV infection were analyzed retrospectively, which included clinical and auxiliary examination, pathological data, especially EB virus (EBV)-antibodies and DNA in peripheral blood mononuclear cells (PBMC) and infected tissue, and follow-up information.</p><p><b>RESULT</b>Of the 12 cases, 7 were male and 5 were female. The age at the onset of diseases ranged from 35 months to 14 years (median, 11 years). The major manifestations were fever (100%), splenomegaly (91.7%), hepatomegaly (83.3%), lymphadenopathy (75.0%), and others, including skin rash, development retardation, jaundice, ascites, pulmonary hypertension, oral ulcer, cholecystitis and pleural effusion. The abnormalities of auxiliary examination were as follows: elevated LDH level (91.7%), liver dysfunction (83.3%), anemia (75.0%), leukopenia (58.3%), neutropenia (50.0%), thrombocytopenia (25.0%) and abnormal chest X-ray findings. At the time of onset, 58.3% of the patients had an IM-like illness. In all of the 12 cases, EBV serologic tests revealed high IgG antibody levels against EB viral capsid antigen (VCA). The patients often had positive IgM and IgA antibodies against VCA (33.3% and 66.7%) as well. Elevated IgG antibody level to early antigen (EA) (100.0%), occasionally positive IgA antibody (40.0%) were also seen. The mean load of EBV-DNA detected by real-time polymerase chain reaction (PCR) in the PBMC was (8.12 x 10(6), median)copies/ml. Four of 12 cases presented a poor clinical course, two of whom died from EBV-associated HPS, 1 from severe multiple pathogens infection, and 1 from multiple organ failure. In addition, 1 case developed Hodgkin's T cell lymphoma and another case showed hepatopulmonary syndrome in 2 years after splenectomy.</p><p><b>CONCLUSIONS</b>The clinical feature of SCAEBV infection varied exceedingly. EBV-DNA load in PBMC of SCAEBV infected patients was significantly increased. More attention should be paid to the disease because of its severe complications, poor prognosis and high mortality.</p>

Clinical and molecular genetic study on two patients of the juvenile form of Pompe disease in China / 中华儿科杂志

<p><b>OBJECTIVE</b>Glycogen-storage disease type II (GSD II, Pompe's disease) is an autosomal recessive disorder caused by a functional deficiency of acid alpha-glucosidase (GAA) that leads to glycogen accumulation within lysosomes in most tissues. The GAA gene is located to human chromosome 17q25 and contains 20 exons, 19 of which are coding. Clinically, patients with the severe infantile form of GSD II have muscle weakness and cardiomyopathy eventually leading to death before the age of two years. Patients with the juvenile or the adult form of GSD II present with myopathy with a slow progression over several years or decades. A broad genetic heterogeneity has been described in GSD II in Europe, South Africa, USA, Japan and Korea, however, the investigation has not been performed in the patients from the mainland of China. In this study, clinical analysis and mutation detection were done on Chinese patients.</p><p><b>METHODS</b>Two unrelated juvenile patients with late onset GSD II (one boy, 3 years old and one girl, 9 years old) were included in the study with the informed consents. The diagnosis was confirmed by alpha-glucosidase determination in cultured fibroblasts. In addition, their clinical presentation, laboratory findings, electrophysiologic studies and muscle biopsy findings were analyzed in detail. Genomic DNA samples were extracted from fibroblasts of the probands, from peripheral blood of their parents and 50 unrelated, normal individuals. All the coding 19 exons and exon-intron boundaries of GAA were detected in the proband by polymerase chain reaction (PCR) and direct sequencing.</p><p><b>RESULTS</b>One patient presented decrease of muscle strength, limb-girdle hypotonia, the other patient presented reduced muscle volumes and respiratory problems. Both had increased CPK value, myopathic pattern on EMG; vacuoles on muscle biopsy, and deficiency of 1, 4-alpha-glucosidase activity. After 1 year follow up, the girl died after pneumonia at 10 years of age. One patient was found to be compound heretozygote for the novel mutation Arg702His, and the previously reported mutation Pro266Ser, which was reported in Korean population, with the late-onset phenotype. Two novel missense mutations Thr711Arg, Val723Met were found on the other patients.</p><p><b>CONCLUSIONS</b>Three mutations identified in the patient were new missense mutations causing late onset GSD II, which had not been reported elsewhere before.</p>