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PubMed2002

Combined Ala601-Thr-type dysplasminogenaemia and antiphospholipid antibody syndrome in a patient with recurrent thrombosis.

A 44-year-old man was admitted to our hospital because of recurrent thrombosis. Laboratory findings showed that he had antiphospholipid antibody syndrome (APS) associated with systemic lupus erythematosus. Plasminogen activity was reduced (21%), but its antigenic level was rather elevated (16.4 mg/dl). The discrepancy of plasminogen activity and antigen levels was also found in his three daughters. Gene analysis revealed a homozygous missense mutation (Ala601-->Thr) at exon 15 of the plasminogen gene in the patient and a heterozygous mutation in his three daughters, suggesting that the patient has dysplasminogenaemia, which was reported as "plasminogen Tochigi." Although it still remains controversial whether both dysplasminogenaemia and plasminogen deficiency are relevant independent thrombotic risk factors, the combination of this deficiency and APS should be considered as a strong predisposition to thrombosis in this patient.

Adult↗
PubMed1997

A novel mitochondrial tRNA phenylalanine mutation presenting with acute rhabdomyolysis.

We describe a patient who presented with acute rhabdomyolysis and had 68% cytochrome c oxidase (COX)-deficient fibers in skeletal muscle. Further investigations confirmed a respiratory chain defect that was associated with a novel heteroplasmic point mutation in the phenylalanine tRNA gene of the mitochondrial genome (mtDNA). Analysis of single muscle fibers revealed a significantly greater level of mutant mtDNA in COX-negative fibers. This is the first case of a mitochondrial tRNA gene point mutation presenting with acute rhabdomyolysis and recurrent myoglobinuria.

Acute Disease↗
PubMed2003

[Turkish children with recurrent abdominal pain and fever: familial Mediterranean fever].

Four children of Turkish origin, three boys aged 12, 8 and 7 years, and a girl aged 5 years, presented with clinical symptoms of familial Mediterranean fever. They had the characteristic episodes of fever combined with abdominal pain, thoracic pain, general malaise or arthralgia. Familial Mediterranean fever is an autosomal recessive genetic disorder restricted to people originating from the Middle East. The causative gene (MEFV) and many missense mutations have been identified. The clinical syndrome is characterised by self-limiting febrile episodes accompanied by inflammation of the serous membranes, resulting in peritonitis, pleuritis or synovitis. In untreated patients systemic amyloidosis may develop, which manifests as renal insufficiency. The diagnosis is based on the characteristic medical history and is confirmed by DNA analysis. Meanwhile, treatment with colchicine can be started. This is effective in 90% of affected patients. Being aware of the prevalence of familial Mediterranean fever in immigrant populations can improve the quality of life and prevent long-term complications.

Abdominal Pain↗
PubMed2005

Protein C Sapporo (protein C Glu 25 --> Lys): a heterozygous missense mutation in the Gla domain provides new insight into the interaction between protein C and endothelial protein C receptor.

Interaction of the gamma-carboxyglutamic acid (Gla) domain of protein C with endothelial protein C receptor (EPCR) is a critical step for efficient activation of protein C, though interactions by mutants in the Gla domain of protein C with EPCR have been rarely evaluated. We identified a 44-year-old Japanese woman with a history of recurrent thromboembolism as an inherited missense mutation, the first such case reported in Japan, which involved a protein C Gla 25 mutation. Total protein C antigen and Gla protein C antigen levels in the proband were normal. Protein C activity measured with an anticoagulant assay was reduced, whereas that measured with an amidolytic assay was normal. She was therefore phenotypically diagnosed as type IIb protein C deficiency. Direct sequencing of the PCR fragments revealed a heterozygous G to A transition at nucleotide position 1462 in exon 3, which predicted an amino acid substitution of Glu 25 by Lys. Her mother and one son were also heterozygous for this mutation. A molecular dynamics simulation of Gla 25-->Lys/EPCR complex in water suggested that the affinity between the molecules was decreased compared to the wild type Gla domain/EPCR complex. Since Gla 25 has been shown to play an important role in protein C function, not only in membrane phospholipid binding but also in binding to EPCR, our findings provide new insight into the mechanism by which the Glu 25-->Lys mutation induces type IIb protein C deficiency in individuals.

Adult↗
PubMed2001

Recurrent acute pancreatitis: an algorithmic approach to identification and elimination of inciting factors.

Recurrent acute pancreatitis represents a challenging clinical problem associated with significant morbidity, impairment in quality of life, and expense. If unchecked, recurrent episodes of acute pancreatitis may lead to chronic pancreatitis. In this work we have combined the opinion of experts in pancreatology and an extensive review of the literature to develop a logical algorithm that facilitates the stepwise identification and elimination of inciting factors using current technology. The approach taken in recurrent acute pancreatitis is clearly dependent on adequate and appropriate evaluation and treatment of the patient with an initial episode of acute pancreatitis. Future advances in the treatment of these patients will almost certainly depend on improved imaging modalities, prospective clinical trials assessing the efficacy of endoscopic and surgical intervention, a better understanding of mutations and pathophysiologic mechanisms responsible for recurrent acute pancreatitis, and the development of novel, effective preventive and therapeutic strategies.

Acute Disease↗
PubMed2003

Natural history of pancreatitis associated with cystic fibrosis gene mutations.

BACKGROUND: An increased incidence of CFTR mutations has recently been reported in chronic and idiopathic pancreatitis. AIM: The aim of the study was to verify these data and describe the clinical, morphological and histological findings in 99 patients (59 males, 40 females, mean age 40+/-16 years), 45 suffering from idiopathic chronic pancreatitis and 54 from acute recurrent pancreatitis. METHODS: Each subject was screened for the 18 CFTR mutations: DF508, DI507, R1162X, 2183AA>G, 21303K, 3849+10KbC>T, G542X, 1717-1G>A, R553X, Q552X, G85E, 711+5G>A, 3132delTG, 2789+5G>A, W1282X, R117H, R347P, R352Q), which cover 72% of cystic fibrosis chromosomes in the Italian population, plus the 5-thymidine allele in intron 8 of the CFTR gene (IVS85T). RESULTS: Among the 99 patients, we found 14 patients with CFTR mutation (14.1%). Three idiopathic chronic pancreatitis patients had cystic fibrosis (compound mutations in two and a single mutation with a pathological sweat test in one) and 11 (11.1%) presented a single mutation (carriers) (seven idiopathic chronic pancreatitis and four acute recurrent pancreatitis). The incidence of patients with cystic fibrosis was 167.5 times higher than that observed in the general population, whereas the carrier frequency was 4.43 times higher for chronic pancreatitis and 2.11 times for acute recurrent pancreatitis than that observed in 428 unrelated partners of cystic fibrosis patients. The prevalence of IVS8-5T was similar (7.1%) to that of the general population (10%). All idiopathic chronic pancreatitis patients with one or more CFTR gene mutations had a long history of recurrent attacks of pancreatitis. The length of recurrences of pancreatitis before diagnosis of chronic pancreatitis was shorter in chronic pancreatitis patients with one or more CFTR gene mutations than in the other idiopathic chronic pancreatitis patients (7.4+/-5.8 vs. 2.1+/-2 years). In idiopathic chronic pancreatitis patients with one or more CFTR gene mutations, exocrine and endocrine insufficiency (diabetes and steatorrhoea) were rare or delayed events. CONCLUSIONS: The natural history of pancreatitis associated with CFTR gene mutations seems to be characterised by recurrences of pancreatitis which develops into chronic pancreatitis.

Acute Disease↗
PubMed1996

[Analysis of cell origin of human hepatocellular carcinoma according to p53 gene mutation].

Paraffin-embedded hepatocellular carcinoma (HCC) samples were used to study point mutation of p53 gene at 249 codon in the exon 7 by polymerase chain reaction and gel electrophoresis under Hae III enzyme digestion. Fourteen primary tumor foci and 15 recurrent tumor foci from 11 patients were investigated. p53 gene point mutation was detected in 10 of 14 primary foci (71.4%), in 10 of 15 recurrent foci (66.7%) and in 10 of 12 multiple foci. The p53 genotype of the primary and recurrent tumor foci was the same in 5 patients but different in 6. The p53 genotype of the primary and recurrent tumor foci was identical in 5 patients with multiple tumor nodules. The results suggest that recurrent HCC was multi-centric in origin in 7 of the 11 patients but was mono-centric in the other 4 patients studied.

Adult↗
PubMed1999

p53 mutations predict non-small cell lung carcinoma response to radiotherapy.

In vitro and animal studies, the effect of loss of p53 function on radiosensitivity is controversial. p21Waf1/Cip1 is a potent inhibitor of cyclin-dependent kinases and p21 gene polymorphisms are associated with some human cancers. We sought to determine whether p53 mutations or p21 polymorphisms affect response to radiotherapy in patients with recurrent non-small cell lung carcinoma (NSCLC). Thirty-four patients with NSCLC who underwent radiotherapy for recurrent tumors after potentially curative resection were studied. Gene alterations or polymorphisms were analyzed in DNA from the primary tumor tissue, and the response to radiotherapy was based on the metastatic lesion. Mutations in exons 5-8 of the p53 gene were detected by polymerase chain reaction (PCR)-single strand conformation polymorphism (SSCP) analysis. p21 gene polymorphisms were identified by restriction digestion (BsmAI or PstI) of PCR products. Mutations in p53 were found in 13 of 34 patients (38.2%). The response rates (complete plus partial) were 15.4% for patients with tumors having p53 mutations and 61.9% for patients with wild-type p53 (P = 0.013). There was no significant difference between p21 polymorphisms and response to radiation. p53 gene mutations predict response to radiotherapy in NSCLC. Our results provide clinical support for the in vitro model that loss of p53 function decreases radiosensitivity.

Adult↗
PubMed2006

Renal amyloidosis in a child with sickle cell anemia.

The kidney is frequently affected in patients with sickle cell syndrome, i.e., homozygous and heterozygous patients, with a consequently large spectrum of renal abnormalities that may range from minimal functional changes to chronic renal failure. Here, we present a 13-year-old boy with sickle cell anemia (SCA) (HbSS) who was referred to our unit with nephrotic syndrome. Renal biopsy revealed AA type amyloidosis on the basis of light microscopic findings, indicating Congo red staining and immunohistochemistry. He had neither a family history of familial Mediterranean fever (FMF) nor any complaint of recurrent abdominal pain, arthritis, and fever, but frequent painful vaso-occlusive crises. The patient was found to have no MEFV gene (Mediterranean feVer) mutations either. Painful episodic attacks might provoke recurrent acute inflammation, leading to repeated stimulation of acute phase responses and cause secondary amyloidosis. To our knowledge, this boy is the first case of SCA complicated by renal amyloidosis observed in childhood.

Adolescent↗
PubMed2002

Non-inversion factor VIII mutations in 80 hemophilia A families including 24 with alloimmune responses.

Heteroduplex screening identified 74 small mutations in the factor VIII genes of 72 families with hemophilia A. In addition, patients from 3 families with high titer inhibitors had partial gene deletions and 5 unrelated families that were negative for heteroduplex formation had a mutation on direct sequencing. The latter had mild hemophilia A with an inhibitor, and sequencing their exon 23 fragments found a transition predicting a recurrent Arg2150 to His. Of 69 distinct mutations (including the 3 partial gene deletions), 47 are novel. Of small mutations, 51 were missense (one possibly a normal variant and two that could also alter splicing) at 39 sites, 13 were small deletions or insertions (3 inframe and one a normal variant in an intron), 13 were nonsense at 12 sites and 2 altered intron splice junctions. In 24 families, at least one affected member had evidence for an alloimmune response to factor VIII: of these, 11 were associated with missense mutations. In 14 families, de novo origin was demonstrated.

Alternative Splicing↗
PubMed2002

[Relationship between core gene mutations of hepatitis B virus and response to alpha interferon therapy in chronic hepatitis B].

BACKGROUND/AIMS: Treatment of chronic hepatitis B with interferon results in a sustained loss of hepatitis B virus DNA and hepatitis B e antigen (HBeAg) and remission of liver disease only in a proportion of cases. Recently, mutations of hepatitis B virus (HBV) core gene have been reported as being related to the failure of interferon treatment in chronic hepatitis B. This study investigated whether core gene mutations of HBV are related to non-response to interferon therapy and whether the recurrence of HBeAg and HBV DNA in initial responders to interferon therapy is associated with the emergence of HBV core gene mutants. METHODS: The precore/core gene sequence was determined by polymerase chain reaction (PCR) and direct sequencing of PCR product in serum samples obtained before interferon treatment from 10 responders and 10 non-responders to interferon therapy. In addition, precore/core gene sequence was determined in serum samples obtained before interferon treatment and after recurrence from 10 patients who showed recurrence of HBeAg and HBV DNA after initial response to interferon therapy. RESULTS: In samples from 10 responders, there were 7 missense mutations and 71 silent mutations. However, there were 43 missense mutations and 109 silent mutations in samples from 10 non-responders. In samples obtained before interferon treatment from the 10 patients who showed recurrence after initial response, 8 missense mutations and 74 silents mutations were found. The nucleotide sequences from the samples obtained after the recurrence showed 6 silent nucleotide substitutions compared with the sequences from the samples obtained before interferon treatment. CONCLUSIONS: Mutations in the core protein of HBV occur more frequently in non-responders than responders to interferon therapy of chronic hepatitis B and may be a factor responsible for the failure of interferon treatment. The recurrence of HBeAg and HBV-DNA in initial responders to interferon therapy is not associated with the emergence of the HBV core gene mutants.

Adolescent↗
PubMed1995

The clinical significance of p53 gene mutation in hepatocellular carcinomas from Japan.

To clarify the clinical significance of the mutation of p53 gene in hepatocellular carcinoma (HCC), 90 resected specimens from Japanese patients were assayed using a polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. p53 mutations were detected in 25 cases (27.8%) at exons 4, 5, 6, 7, and 8, and the most frequent region of the mutation was at exons 5 and 7. No statistically significant correlation was observed between the p53 mutations and the clinical features except for the preoperative alpha-fetoprotein (AFP) level (P < .05). According to the pathological features, prognostic factors, such as size of the tumor, vascular invasion, fibrous capsule infiltration, and intrahepatic metastasis, showed no relationship to the existence of the mutation. However, p53 mutations were significantly associated with the degree of differentiation of HCC; that is, the mutation was found in 19 cases of 53 poorly differentiated HCCs (35.9%) and 2 of 3 cases of anaplastic HCCs (66.7%). The presence of p53 mutations was associated with a shortened cancer-free survival (P < .001, by log rank test) and a shortened survival (P < .05). A multivariate analysis by the Cox regression analysis showed that the p53 mutations were an unfavorable prognostic factor related to recurrence (P < .005), which is especially significant within the first postoperative year. These results suggest that the mutations of p53 gene of HCC might be an independent prognostic predictor to help in the selection of candidates who should undergo more intensive postoperative treatment.

Adult↗
PubMed1998

Somatic mosaicism: a common cause of classic disease in tumor-prone syndromes? Lessons from type 2 neurofibromatosis.

Blood samples from 125 families with classic type 2 neurofibromatosis with bilateral vestibular schwannomas were analyzed for mutations in the NF2 gene. Causative mutations were identified in 52 families. In five families, the first affected individual in the family (the index case) was a mosaic for a disease-causing mutation. Only one of nine children from the three mosaic cases with children are affected. Four of these nine children inherited the allele associated with the disease-causing mutation yet did not inherit the mutation. NF2 mutations were identified in only 27/79 (34%) of sporadic cases, compared with 25/46 (54%) of familial cases (P<.05). In 48 families in which a mutation has not been identified, the index cases have had 125 children, of whom only 29 are affected with NF2 and of whom only a further 21 cases would be predicted to be affected by use of life curves. The 50/125 (40%) of cases is significantly less than the 50% expected eventually to develop NF2 (P<.05). Somatic mosaicism is likely to be a common cause of classic NF2 and may well account for a low detection rate for mutations in sporadic cases. Degrees of gonosomal mosaicism mean that recurrence risks may well be <50% in the index case when a mutation is not identified in lymphocyte DNA.

Adult↗
PubMed2005

Heterozygous mutations in the LDL receptor-related protein 5 (LRP5) gene are associated with primary osteoporosis in children.

UNLABELLED: Three of 20 patients with juvenile osteoporosis were found to have a heterozygous mutation in the LRP5 gene. No mutations were found in the type I collagen genes. Mutations in the other family members with similar bone phenotype confirmed that LRP5 has a role in both juvenile and adult osteoporosis. INTRODUCTION: The gene encoding the low-density lipoprotein receptor-related protein 5 (LRP5) gene has recently been shown to affect bone mass accrual during growth and to be involved in osteoporosis-pseudoglioma syndrome and a high bone mass phenotype. Mutations in the type I collagen genes (COL1A1 and COL1A2) are known to cause osteogenesis imperfecta, characterized by increased bone fragility. MATERIALS AND METHODS: Here we analyzed COL1A1, COL1A2, and LRP5 for mutations in 20 pediatric patients with primary osteoporosis characterized by low BMD, recurrent fractures, and absent extraskeletal manifestations. RESULTS AND CONCLUSIONS: No mutations were detected in the type I collagen genes, but two missense mutations (A29T and R1036Q) and one frameshift mutation (C913fs) were found in the LRP5 gene in three of the patients. The frameshift mutation was also seen in the proband's father and brother, who both were found to have significant osteoporosis. R1036Q was observed in the proband's mother and two brothers, who all had osteoporosis. These results indicate that heterozygous mutations in the LRP5 gene can cause osteoporosis in both children and adults.

Adolescent↗
PubMed2000

[Leiden, G20210A mutations in prothrombin gene and antiphospholipid antibodies in systemic lupus erythematosus and antiphospholipid syndrome].

AIM: To estimate incidence rate of Leiden mutation in factor V gene, prothrombin gene mutation responsible for replacement of G for A in position 20210 (G20210A) of its 3'-end noncoding part in patients with systemic lupus erytheamtosus (SLE) and antiphospholipid syndrome (APS) and their relationships with antiphospholipid antibodies (aPL): lupus anticoagulant (LA) and anticardiolipin antibodies (aCL). MATERIALS AND METHODS: The trial included 33 patients (2 males and 31 females) aged 20-62 years (mean age 32.7 +/- 9.8 years). 29 patients suffered from SLE, 17 of them had also APS (criteria by G. R. V Hudhes). 3 patients had primary APS, 1 female had hemorrhagic vasculitis. IgG and IgM-aCL were detected by enzyme immunoassay. In revealing mutation, DNA was used isolated from peripheral blood by standard methods based on polymerase chain reaction (PCR). Primary screening of Leiden mutation was made according to Bertina et al. with Mnl I restrictase. The mutation was confirmed by an original technique with allele-specific primers. G20210A mutation in the prothrombin gene was determined with restrictase Taq I after introduction of artificial restriction site in PCR product. The patients were divided into 2 groups. Group 1 incorporated 12 patients with SLE without APS. Group 2--21 patients with APS (17 with SLE + APS, 3 with primary APS and 1 with hemorrhagic vasculitis). RESULTS: Patients of group 1 had neither thrombotic complications nor Leiden mutation. Two patients of group 2 had heterozygous Leiden mutation. Both females were aPL-positive and had previously recurrent thrombophlebitis. One of them had also recurrent disorders of cerebral circulation. None of the examinees had any G20210A mutations in the prothrombin gene. CONCLUSION: Detection of genetic defects in APS provide arguments in the dispute about the necessity, duration and choice of anticoagulant therapy. If patients with APL syndrome appeared to have besides aPL also genetic defects in coagulation, this will enable identification of patients at high risk of thrombosis which need permanent administration of anticoagulants among which only low-molecular ones or glycosaminoglycanes are indicated. Mutation in gene of factor V is absolute contraindication to phenilin and quamarines.

Adult↗
PubMed2001

Muscle weakness in a Japanese family of Arg1239His mutation hypokalemic periodic paralysis.

Familial hypokalemic periodic paralysis is an autosomal dominant disorder. Recently, three predominant mutations were found in the muscle dihydropyridine-sensitive calcium channel alpha 1-subunit gene. We present a Japanese family that displays one of these, the Arg1239His mutation. All the affected individuals of this family displayed this mutation. Two cases had a history of recurrent episodes of muscle weakness and difficulty in running before their first paralytic attack. It is suggested that there are no racial differences with this mutation, and that mild muscle weakness occurs not only after but also preceding the first attack.

Adult↗
PubMed2006

A syndrome of holoprosencephaly, recurrent infections, and monocytosis.

We describe three siblings with holoprosencephaly, recurrent infections, and increased peripheral blood monocytes. These children were born to apparently healthy parents in a family with one unaffected child. Affected individuals had microcephaly, severe developmental delay, failure to thrive, and brachydactyly. The clinical courses were complicated by endocrine dysfunction, multiple respiratory, and skin infections. Laboratory studies showed normal karyotypes, normal lymphocyte function, and a peripheral blood monocytosis with markedly abnormal morphology. Mutation analysis of the seven genes (SHH, ZIC2, SIX3, TGI, FTDGF1, GLI2, and PTCH) known to be involved in holoprosencephaly was normal. This is the first report demonstrating an association between abnormal mononuclear phagocytes and holoprosencephaly.

Abnormalities, Multiple↗