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PubMed2002

Evaluation of referrals for genetic investigation of short stature in Hong Kong.

OBJECTIVE: To establish a profile of the causes of apparently unexplained SS in genetic referral center and evaluate the current referral system. METHODS: This was a retrospective database survey on patients who were referred our clinical genetic service from 1988 - 1998 primarily because of SS. We retrieved the study population from our computer database using "short stature"as a search handle and then studied the demographic, clinical and laboratory data from their medical records. RESULTS: Three hundred and fifty-three subjects were referred for genetic evaluation of SS in 1988 - 1998. The mean age of referred subjects was 11.5 years and the female to male ratio was 7.6. All referrals had undergone cytogenetic studies to exclude chromosomal abnormalities, 19% of girls with apparently unexplained short stature had Turner syndrome; at least 47.9% of the study population were normal variants and 25% of the referrals had inadequate information for classification. CONCLUSIONS: Genetic investigation is essential in the management of patients with SS, especially for girls suspected of having Turner syndrome, in which growth hormone treatment has shown to improve final height. We also highlight the inherited causes of short stature, which were often misdiagnosed as benign familial short stature, and discussed the drawbacks of the current referral system.

Child↗
PubMed2003

Primary endocrinomas (carcinoids and variant neoplasms) of the gallbladder. A statistical evaluation of 138 reported cases.

This study was carried out to obtain extensive information on carcinoids (the carcinoid group) and related variant endocrinomas (the variant group) of the gallbladder, and to statistically analyze their characteristics from various clinicopathologic aspects. A total of 138 cases were collected from the international sources, 101 belonging to the carcinoid group and 37 to the variant group. The first group consisted of 81 cases of typical and 20 atypical carcinoids. Comparative evaluation was attempted mainly between the carcinoid and variant groups, and occasionally between the typical and atypical carcinoid series when statistical significance was suspected. The carcinoid group showed a statistically significant difference from the variant group by exhibiting a younger average age (61.7 years vs 69.7 years: P<0.01), a higher incidence of associated cholelithiasis (87.3% vs 56.0%: P<0.01), a higher incidence of small tumors 50 mm or less (85.2% vs 52.9%: P<0.01), a smaller average tumor-size (29.6 mm vs 58.7 mm: P<0.01), a lower rate of metastases (40.7% vs 70.6%: P<0.05), a higher immunoreactivity rate of chromogranin (100.0% vs 66.7%: P<0.01), a lower immunoreactivity rate of gastrin (23.8% vs 70.6%: P<0.01), and a higher five-year survival rate (60.4% vs 21.3%: P<0.0005). Significant differences in various clinicopathological aspects confirmed between the carcinoid group and the variant group suggested that endocrine carcinomas of these two groups perform a different clinical pattern, represented most clearly by postoperative outcomes. These groupings are decided on the basis of histologic patterns, namely, well to poorly differentiated endocrine carcinomas (typical to atypical carcinoids) and undifferentiated or anaplastic variants of other endocrine carcinomas. The basic criteria for such classification of these endocrine carcinomas based on international agreements are required.

Age Factors↗
PubMed1992

Cluster headache.

In this article we describe the clinical features, natural history, and clinical variants of cluster headaches, following the modern International Headache Society classification of cluster headaches in its two types: episodic and chronic. The basic pathophysiology is considered to be the trigeminal vascular system, the common final pain pathway, with pain initiated in a cyclical fashion by disordered central hypothalamic pacemaker. Oxygen, rapidly acting ergotamine, or dihydroergotamine preparations serve as abortive treatment of acute attacks; various pharmacotherapeutic options and combination therapies aid in the prophylaxis of cluster headache; and trigeminal radio frequency gangliorhizolysis is a very useful surgical approach in patients with chronic cluster headache who are resistant to medical treatment.

Cluster Headache↗
PubMed1991

[Criteria for evaluating the severity of craniocerebral trauma in children].

The article discusses the total results of multifactorial analysis of observations over 16,000 children with isolated and more than 400 with combined craniocerebral trauma (CCT) in the light of the peculiarities of the child age and the current trends in studying the problem in the Soviet Union and other countries. From these standpoints, the author first gives a clinicomorphological characterization of CCT types in children, deals with the methods and prospects of objectivication of the evaluation of the severity of isolated and combined CCT, extracranial local injuries in polytrauma, totally determining the severity of the general condition and the efficacy and prognosis of the diagnostic and therapeutic measures. Original methods for quantitative evaluation of the degree of severity of the trauma, which were developed in the clinic, are described. A variety of the clinical CCT forms and the possible variants of the concomitant injuries are systematized in a CCT classification approximated maximally to the solution of practical problems under different conditions, including extreme conditions in mass injuries. For this purpose, the author uses conventional designations for the main gradients of the pathophysiological reactions of the child's organism depending on the location and severity of the concrete damages and the general condition, making a coded recording of the diagnosis possible, which makes easier the sorting out and registration of the patients and orientation as regards the order in which aid should be given and the volume of the therapeutic and diagnostic programs with the use of computers. The patients were subjected to general clinical examination and laboratory tests, as well as special methods of examination (radiography, ultrasonic study, angiography, circulography, computed tomography, etc.). Importance was attached to the results of histological study and the reports of the forensic medical examination committee.

Brain Injuries↗
PubMed1989

[The place of echography in the clinical diagnosis of hepatic hemangioma].

On the basis of 104 hemangiomas diagnosed in 81 patients an ultrasound classification of the disease is made which includes four basic variants. Echotomography detects the tumor most successfully in group I (well outlined homogenous hyperechogenisity) while in the other groups it shows a low percentage of correct diagnoses. The average sensitivity of the method is 60.6%. The possibilities of the other basic diagnostic methods are discussed and a scheme for clinical investigation is proposed. Scintigraphy is of no substantial help, computed tomography increases the percentage of the correct diagnoses, angiography and correctly indicated laparoscopy most often end the clinical investigation. The patients with hemangioma are subjected to a prolonged clinical follow up and ultrasound tomography is the best suitable method for this.

Adult↗
PubMed1988

[Artificial arteriovenous anastomoses in reconstructive surgery of arteries with a poor distal vascular bed].

Based on their experience with the operative treatment of 20 patients with acute thrombosis of major arteries of extremities the authors recommend if indicated to combine reconstructive operation on the arteries with the artificial arterio-venous anastomosis. The authors have developed a classification of such associated operations which facilitates choice of their variants dependent on the state of the distal vascular bed.

Adult↗
PubMed1989

Revised classification of posterior fossa cysts and cystlike malformations based on the results of multiplanar MR imaging.

MR and clinical data on 31 patients with posterior fossa CSF collections were analyzed. A clear separation of these patients into classical categories was not possible because of new information obtained from the MR images. We present a new classification of these disorders. The Dandy-Walker malformation, Dandy-Walker variant, and mega-cisterna magna seem to represent a continuum of developmental anomalies of the posterior fossa. A possible embryologic basis for this continuum is suggested. Discrete posterior fossa CSF collections that are clearly separate from the fourth ventricle and vallecula are classified as posterior fossa cysts. Posterior fossa CSF collections that communicate with the fourth ventricle and are associated with cerebellar atrophy are classified as prominent cisterna magna. Both the Dandy-Walker complex and posterior fossa cysts can cause enlargement of the posterior fossa and scalloping of the inner table of the occipital bone. The Dandy-Walker complex presents with seizures, developmental delay, and enlarging head size; it requires CSF diversion when associated with hydrocephalus. Posterior fossa cysts present with symptoms of a posterior fossa mass; they generally require surgical resection. Prominent cisterna magna is a result of degenerative disorders and requires no surgical therapy. This new classification facilitates both diagnosis and therapy of these disorders. MR revealed that disorders previously referred to as the Dandy-Walker malformation, the Dandy-Walker variant, and the mega-cisterna magna actually are not separate entities, but appear to represent steps on a continuum of developmental anomalies of the posterior fossa. Because of this, we suggest a new term, the Dandy-Walker complex, be used to describe this continuum.

Adolescent↗
PubMed2004

Disease location, anti-Saccharomyces cerevisiae antibody, and NOD2/CARD15 genotype influence the progression of disease behavior in Crohn's disease.

BACKGROUND: Crohn's disease (CD) is characterized by heterogeneity of phenotype. The Vienna classification can be used to classify CD, and recent data illustrate that behavior evolves over the course of the disease. Clinical and biological influences on disease progression remain unclear. We examined the associations of CD disease progression at diagnosis and for up to 20 years of follow-up. METHODS: Two hundred thirty-one well-characterized CD patients were studied. Demographic, clinical, and NOD2/CARD15 data were collected. Disease behavior according to the Vienna classification was assessed at diagnosis and for up to 20 years following diagnosis. RESULTS: At diagnosis, 70% of patients had inflammatory disease, 9% stricturing, and 21% penetrating. Early age at diagnosis was associated with ileocolonic and upper GI disease (p = 0.015), and positive anti-Saccharomyces cerevisiae antibody (ASCA) was associated with ileal involvement (p = 0.008). Smoking was relatively protective against colonic, rather than ileal involvement at diagnosis (p < 0.02). At 20 years, 92% had progressed to a more severe disease type. Patients who progress to a more severe disease type require more frequent surgery (p < 0.00001). Multivariate analysis found disease progression to be associated with ileal disease location (p = 0.001) and positive ASCA (p = 0.003). Variant NOD2/CARD15 alleles were protective against rapid progression of disease phenotype (p = 0.04). The presence of perianal disease was independent of intestinal penetrating disease. CONCLUSIONS: The progression of disease type in CD is associated with the need for more frequent surgery. Rapid progression is associated with ileal disease and positive ASCA, and delayed progression is associated with variant NOD2/CARD15 alleles. Consideration should be given to a separate Vienna classification for perianal disease.

Adult↗
PubMed2007

Relationship between clinical features of Crohn's disease and the risk of developing extraintestinal manifestations.

OBJECTIVES: Crohn's disease is frequently associated with extraintestinal manifestations. The aim of this study was to evaluate the degree of association between the development of extraintestinal manifestations, the clinical forms of Crohn's disease according to the Vienna Classification and to the presence of several potential risk factors of the disease. METHODS: One hundred and seventy-three consecutive Crohn's disease patients were studied. Sex, smoking habits, previous Crohn's disease-related surgery, family history of Crohn's disease, steroid dependency, steroid resistance and the presence of at least one mutant allele in any of the three considered variants of CARD15 gene were considered as potential risk factors. The Vienna Classification was applied, and the presence of extraintestinal manifestations was evaluated. RESULTS: A total of 61 (35.3%) patients developed extraintestinal manifestations. They were more frequently seen in women than in men (41.1 vs. 26.7%), (odds ratio 1.92, 95% confidence interval: 0.99-3.70; P=0.05) and in steroid-dependent patients than in steroid responders (61.1 vs. 28.5%), (odds ratio 3.94, 95% confidence interval: 1.83-8.49; P<0.01). No relationship was found in general between the extraintestinal manifestations of Crohn's disease and smoking habits, previous Crohn's disease-related surgery, a family history of Crohn's disease, steroid resistance and CARD15 mutations. Such relationships were, however, detected for some individual extraintestinal manifestations as between both smoking habits (odds ratio 9.09, 95% confidence interval: 1.15-71.66; P<0.05) and the G908R CARD15 mutation (odds ratio 4.76, 95% confidence interval: 1.11-20.43; P<0.05), respectively, and erythema nodosum. Patients with any colonic involvement of Crohn's disease (L2+L3) suffered from extraintestinal manifestations of the disease more frequently than patients without colonic involvement (42.7 vs. 25.9%, respectively; odds ratio 2.12, 95% confidence interval: 1.10-4.07; P<0.05). CONCLUSIONS: Female gender, steroid-dependency and colonic involvement are associated with the risk of developing extraintestinal manifestations of Crohn's disease.

Adult↗
PubMed1999

Histone variants of H2A and H3 families are regulated during in vitro aging in the same manner as during differentiation.

In a previous communication, we showed that the H2A.1/H2A.2 histone variant ratio decreases in a linear manner during the in vitro aging of human diploid fibroblasts. This ratio is known to decrease in the same manner in progressive stages of development and in the process of differentiation, and is thus considered to be a biochemical marker for differentiation. A detailed analysis of the synthesis of H2A and H3 histone variants as a function of cumulative population doublings in the same in vitro cell system is presented in this study. Quantitative analysis of these variants in the G0 phase, synchronized fibroblasts has shown that their relative amount in chromatin, as well as their biosynthesis rate, change during in vitro aging of human diploid fibroblasts, revealing both up-and down-regulation of certain variants as a function of cumulative population doublings. Furthermore, we show by morphometric studies employing the seven distinct fibroblast morphotypes, as described by the Bayreuther classification, that this regulation is attributable to the replicative sub-populations. These results reveal that histone variants of the H2A and H3 families are regulated during in vitro aging in the same manner as that during differentiation.

Cell Differentiation↗
PubMed1997

A comparative study on morphology and immunohistochemistry of rhabdomyosarcoma and embryonal skeletal muscles.

OBJECTIVE: To investigate the histologic and histogenetic relationship between various types of rhabdomyosarcomas (RMS) and embryonal skeletal muscle (ESM) for further understanding of the histogenesis, classification and pattern of differentiation of RMS. METHODS: Fifty cases of variant types of RMS and 20 cases of ESM at different gestational ages were available. All specimens were stained with HE, PAS, Van Gieson, Masson, phosphotungstic acid hematoxilin and with antibodies for the demonstration of vimentin, desmin, HHF-35 and myoglobin by ABC method. RESULTS: The results showed that the order of positive expression and the intensity of positive reaction of the different immunohistochemical staining were consistent with the degree of differentiation of the tumor and the development of the ESM. It is obvious that each type of RMS is composed of tumor cells in different degree of differentiation and is derived from primitive mesodermal cells which are capable of potential differentiation towards mature skeletal muscles. CONCLUSIONS: Based on the results of this study, an ideal histologic classification of RMS should reflect not only the cell morphology and histologic structures but also the degree of differentiation of the tumor cells.

Adolescent↗
PubMed2003

[Glucose-6-phosphate dehydrogenase (G6PD) deficiency--a cause of anaemia in pregnant women].

Glucose-6-phosphate dehydrogenase (G6PD) is one of the most important cytoprotective enzymes for oxidative stress. The WHO classification of G6PD deficiency, based on enzyme activity and clinical significance, distinguishes five variants. Chronic haemolytic process is rare and the main factors causing haemolysis are: infections, substances derived from plants, drugs with high oxidation-reduction potential, stress, ketoacidosis in diabetes and surgery operations. We report two cases of women belonging to the class 3 of the WHO classification in whom haemolysis occured during pregnancy. One of the patients developed two incidents of haemolytic anaemia. The cause of the first episode, nine months before pregnancy, was probably infection of the urinary tract caused by Escherichia coli, but the influence of the drugs also cannot be excluded. Because of the genetic background of this enzymopathy we also examined members of the patients, families but did not find any evidence of G6PD deficiency among them. The reported cases indicate that haemolytic anaemia caused by G6PD deficiency may occur during pregnancy what can lead to many not only haematological but also serious obstetrical complications such as infertility, fetus malformations and even its death. We also draw attention to several difficulties in diagnosing G6PD deficiency especially during haemolysis.

Adult↗
PubMedDate not supplied

Eosinophilic fasciitis: a distinct clinical entity?

Eosinophilic Fasciitis is a syndrome characterized by exertion related scleroderma-like skin changes, peripheral eosinophilia, hypergammaglobulinemia and diffuse faciitis. Controversy exists as to the precise classification of the syndrome, i.e., whether it is a distinct entity or a variant of scleroderma. We describe a patient with eosinophilic faciitis but with several unique features: 1) progressive skin changes unresponsive to corticosteroid therapy; 2) elevated anti-DNA antibodies; 3) hypocomplementemia; and 4) a followup biopsy showing sclerodermatoid skin changes. These features and others relating to the controversial aspects of classification of eosinophilic fasciitis are discussed.

Diagnosis, Differential↗
PubMed1989

Genetic variability for pathogenicity, isozyme, ribosomal DNA and colony color variants in populations of Rhynchosporium secalis.

Samples of Rhynchosporium secalis were collected from two experimental barley populations known to carry a diverse array of alleles for resistance to this fungal pathogen. Classification of 163 isolates for four putative isozyme systems, a colony color dimorphism and 20 ribosomal DNA restriction fragment length variants revealed 49 different multilocus phenotypes (haplotypes). The six most common haplotypes differed significantly in pathogenicity. Genetic analyses of the data indicated that effective population sizes of the fungus were very large, that the effects of genetic drift were small, and that negligible recombination occurred in the populations studied. Frequency dependent selection was suggested as an explanation for the maintenance of variation in pathogenicity in the fungus.

DNA, Fungal↗
PubMed2000

A morphometric analysis of cytological features of tall cell variant and classical papillary carcinoma of the thyroid.

In order to assess whether morphometric parameters could be of value in distinguishing between tall cell variant and classical pattern of thyroid papillary carcinoma, the fine needle aspiration cytology (FNAC) samples of 14 cases were analysed using Arcimage 5 software on an Acorn computer. Histological examination of the specimens allowe classification of nine of them as classical pattern and the remaining five as tall cell variants. The nuclear diameter (NDD) and standard deviation distribution (NDSDD), th nuclear area (NAD) and standard deviation distribution (NASDD), and the nuclear/cytoplasmic ratio (NCR) were assessed on May-Grunwald-Giemsa stained smears. Statistical analysis was performed by use of one-way analysis of variance (ANOVA) of the two groups as identified by histology. Whilst NDD (P = 0.007), NAD (P = 0.015) and NADSD (P = 0.026) all appeared statistically significant, NDSD (P = 0.06) and NCR (P = 0.71) were not. The cytological diagnosis of papillary carcinoma is established and reproducible, but morphometric data on the thyroid have so far focused on the differential diagnosis between benign and malignant nodules. The choice of simple morphometric parameters appears to be helpful in the preoperative distinction between the classical pattern and tall cell variant of papillary carcinoma.

Biopsy, Needle↗
PubMed2004

Nonsaccular aneurysms of the azygos anterior cerebral artery.

OBJECT: The azygos or undivided anterior cerebral artery (ACA) is a rare variant, and aneurysms associated with this variant are particularly rare. Most reported azygos ACA aneurysms are saccular, but the authors encountered four patients with this variant who had nonsaccular aneurysms. A review of the management of these lesions and this morphological distinction is presented. METHODS: A retrospective review of patients with aneurysms treated over a 6-year period identified five Type I (according to the Baptista classification) azygos ACA lesions, of which four were nonsaccular. Aneurysms associated with other ACA variants (Baptista Types II and III) were excluded. Azygos ACA aneurysms accounted for 0.5% of all treated lesions and 1.7% of all ACA and anterior communicating artery aneurysms. One lesion in this series was located proximally at the azygos ACA origin, and three were located distally. All four aneurysms were large (>10 mm in diameter), and two were thrombotic. All aneurysms were treated with microsurgical clip occlusion. CONCLUSIONS: Azygos ACA aneurysms are rare, and may have unusual nonsaccular anatomy (for example, fusiform shape, broad base, complex branching, and/or thrombus in the lumen). The nonsaccular morphology of these aneurysms may render them unsuitable for endovascular coil placement, and may complicate their microsurgical management.

Adult↗
PubMed1999

B-cell lymphoma of 708 cases in Japan: incidence rates and clinical prognosis according to the REAL classification.

New insights into the pathogenesis of lymphoid malignancies have been gained through novel techniques such as genetic, molecular and immunologic methods. Recently, based on those findings, a new classification system for lymphoid malignancies, known as the REAL classification, has been proposed. To clarify the relation between the histological classification and prognosis of B-cell lymphoid malignancies, we re-classified 708 cases. In all cases, the B-cell phenotype and/or genotype was confirmed by immunohistochemical staining and/or receptor gene analysis. The most common B-cell lymphoma types were diffuse large B-cell lymphoma (58.8%), follicular lymphoma (12.1%), marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) (9.0%) and mantle cell lymphoma (5.9%). Minor types were lymphoblastic lymphoma (3.4%), Burkitt's lymphoma (2.4%), nodal marginal zone lymphoma (2.1%), lymphoplasmacytic lymphoma (2.0%) and plasmacytoma (1.4%). Rare types were prolymphocytic lymphoma and splenic marginal zone lymphoma. Using overall survival rates, the various B-cell lymphoma types could be divided into three broad groups for prognostic purposes: (1) the low risk group consisted of follicular lymphoma, marginal zone lymphoma of MALT, nodal marginal zone lymphoma, plasmacytoma and lymphoplasmacytic lymphoma; (2) the intermediate risk group consisted of diffuse large B-cell lymphoma, Burkitt's lymphoma and mantle cell lymphoma; and (3) the high risk group consisted of lymphoblastic lymphoma. In MALT, the low grade type had a better prognosis than the high grade type. In diffuse large B-cell lymphoma, the common type had a better prognosis than the variant type, which mainly consisted of the immunoblastic lymphoma. The histological classification will have a benefit for the clinical approach.

Adolescent↗