Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Six new patients with the Cohen syndrome are reported from Finland and 25 published cases from elsewhere are reviewed. New findings are consanguinity among two pairs of parents, granulocytopenia, and marked ophthalmological changes: decreased visual acuity, hemeralopia, constricted visual fields, chorioretinal dystrophy with bull's-eye-like maculae and pigmentary deposits, optic atrophy, and isoelectric electroretinogram. Previously known features of the Cohen syndrome (non-progressive mental retardation, short stature, microcephaly, peculiar facies, slender hands and feet, floppiness, delayed puberty) are confirmed or revised. The ophthalmological features merit attention in the previous and future suspected cases of the Cohen syndrome. Autosomal recessive inheritance can be taken for granted.
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PMID:Further delineation of the Cohen syndrome; report on chorioretinal dystrophy, leukopenia and consanguinity. 670 38

Few investigators have focused on the response of individuals with mental retardation to clozapine. In the general population, some people who have responded to no other psychotropic have had a tremendous positive response, including increased positive scores "quality of life" measures. Clozapine, however, can cause fatal side effects. At least six people in the United States have died from agranulocytosis despite weekly blood counts. The use of clozapine in the general population was reviewed, potential difficulties in prescribing it for individuals with mental retardation discussed, and three relevant case histories presented.
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PMID:Clozapine in three individuals with mild mental retardation and treatment-refractory psychiatric disorders. 798 16

Osteopetrosis is an inherited skeletal condition characterized by increased bone radiodensity. There are three clinical groups: infantile-malignant autosomal recessive, fatal within the first few years of life (in the absence of effective therapy); intermediate autosomal recessive, appears during the first decade of life but does not follow a malignant course; and autosomal dominant, with full-life expectancy but many orthopaedic problems. The infantile variant shows a myelophthisic anemia, granulocytopenia, and thrombocytopenia, and patients eventually die from infection or bleeding or both. Neurologic sequelae include cranial nerve compression (optic nerve, blindness; auditory nerve, deafness; facial nerve, paresis), hydrocephalus, convulsions, and mental retardation. Radiographs show uniform bone density without corticomedulary demarcation, broadened metaphyses, "bone within a bone" or endobone phenomena (tarsals, carpals, phalanges, vertebra, ilium), and thickened growth plates if there is superimposed rickets. Transverse pathologic fractures occur, often followed by massive periosteal bone formation. Computed tomographic scans, magnetic resonance imaging, and bone scans provide specific information. Iliac crest bone biopsy is valuable to quantitate osteoclast and marrow changes by light and electron microscopy. Medical treatments involve high-dose calcitriol to stimulate osteoclast differentiation and bone marrow transplantation to provide monocytic osteoclast precursors. Orthopaedic problems in the intermediate and autosomal dominant forms include increased fractures, coxa vara, long-bone bowing, hip and knee degenerative arthritis, and mandibular and long-bone osteomyelitis. Cranial nerve compression also occurs. Osteotomy, plating, intramedullary rodding, and joint arthroplasty can be done, but are difficult because of bone hardness.
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PMID:Osteopetrosis. Current clinical considerations. 835 40

Clozapine-use patterns in facilities operated by the Texas Department of Mental Health and Mental Retardation are reported. Data collected by manual and automated tracking systems from January 1990 through July 1992 were analyzed to determine patient demographics, the number of patients started on clozapine and the number who stopped taking the drug, the reasons for discontinuation, and other variables. Of 852 clozapine recipients still in the departmental system by the end of the study period, 134 (16%) had discontinued the drug by that date. There were no significant differences in gender, age, or race between the patients who discontinued the therapy and those who did not. Almost one fourth of the patients who discontinued clozapine therapy did so within the first month, and more than 90% did so within the first year. The most common reasons for discontinuing the medication were lack of clinical response, patient refusal or request, and adverse effects, including agranulocytosis. More women than men discontinued the drug because of adverse effects. Although relatively few patients discontinued clozapine during the study period, many had only recently begun taking the drug, and some of these may discontinue it in the near future. Of 852 clozapine-treated patients served by the Texas Department of Mental Health and Mental Retardation between January 1990 and July 1992, 16% discontinued the therapy. One fourth of these did so within the first month of treatment.
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PMID:Use of clozapine in Texas state mental health facilities. 836 20

Cohen syndrome is an autosomal recessive disorder characterized by mental retardation, microcephalia and typical craniofacial features, myopia and chorioretinal dystrophy. As some patients were reported to have leucopenia, we collected the haematological data of 26 Finnish Cohen patients. They all had experienced periods of isolated granulocytopenia from an early age. Granulocytopenia was mild to moderate, non-cyclic and never fatal. Most patients suffered from prolonged or repeated gingival or skin infections. We restudied 16 patients. Bone marrow examination revealed in all patients a normo- or hypercellular marrow, with a left-shifted granulopoiesis in 8/16 patients. The response to adrenaline stimulation was subnormal in 12/14 and to hydrocortisone in 8/16 patients, but administration of rhG-CSF caused granulocytosis in the three patients studied. No bone marrow malignancies were seen.
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PMID:Granulocytopenia in Cohen syndrome. 926 25

Agranulocytosis induced by metamizole is uncommon, with a frequency of less than one case per million treatments. We describe such a case in a patient requiring emergency surgery. An 85-year-old man with a history of infantile paralysis with mental retardation and Paget's disease and X-ray signs of the right femur came to the emergency room with a diaphysial fracture. He received 1 g metamizole i.v. every 8 hours for analgesia. Ten hours after admission a routine blood cell count showed a rapid fall in the number of leukocytes; at 24 hours the count was 600 x 10(9)/l. The diagnosis was agranulocytosis induced by metamizole. Postponement of surgery was advisable and treatment with granulocyte colony stimulating factor (GCSF) at a dose of 5 micrograms/kg/day. Agranulocytosis resolved after 3 days of treatment, after which time the bone was set with a straight femoral plate under subarachnoid anesthesia. Two packs of red blood cells were required during the immediate postoperative period. Twelve days after surgery the patient was released. We review the anesthetic approach to agranulocytosis and its treatment.
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PMID:[Agranulocytosis caused by metamizol. Anesthetic attitude]. 971 23

Our purpose was to perform the first systematic brain magnetic resonance imaging (MRI) study of a substantial number of Cohen syndrome (MIM n:o 216550) patients. 18 Cohen patients and 26 healthy volunteers were examined by MRI (1.0 T). All Cohen patients had essential features of this syndrome: typical facial and structural features, mental retardation, microcephaly, ophthalmologic symptoms, granulocytopenia and cheerful psychic disposition. All our patients belong to the recently published study of refined mapping of the Cohen syndrome gene by linkage disequilibrium. As visual analysis of MR images revealed an impression of a large corpus callosum (CC), quantitative analysis was performed. Sagittal diameter of the body of the CC was larger than that of controls (p = 0.02), whereas all sagittal diameters of the brain stem were markedly smaller (p < 0.0001), as was the midline internal skull surface (MISS) (p < 0.0001). The CC surface did not significantly differ from that of controls significantly. Our main finding, a relatively enlarged corpus callosum, has not previously been reported to associate with mental retardation. Though MRI alone can not confirm the diagnosis and no definite measurements can be recommended for clinical use, any clinical suspicion of this syndrome receives reinforcement through MRI: a relatively enlarged corpus callosum in a microcephalic head and normal signal intensities of the grey and white matters.
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PMID:MRI of the brain in the Cohen syndrome: a relatively large corpus callosum in patients with mental retardation and microcephaly. 1002 48

Our purpose was to perform the first systematic neurological, neurophysiological and psychological study of 18 patients with Cohen syndrome (MIM no 216550), aged 11 months to 57 years (median 27 years). All the patients had the essential features of this syndrome, i.e., typical facial and structural findings, mental retardation, microcephaly, ophthalmologic symptoms, granulocytopenia and a cheerful psychic disposition. Children with the syndrome were considered normal at birth, but upwards of 6 to 12 months, psychomotor retardation became obvious. The first symptoms were microcephaly, which manifested itself by the age of 6 months to 1 year, as well as hypotonia and delayed developmental milestones. Cohen children learned to walk at 2 to 5 years of age. Language development varied markedly. Neurological symptoms did not progress. All patients had normal EMGs. The three youngest (aged 11 months, 3 and 5 years) had normal EEGs, whereas the remainder had low-voltage EEGs. No irritative spikes or epileptoformic foci were found. Nine patients had quick beta transients. Of the 18 patients examined, 4 were profoundly, 11 severely, 1 moderately and 2 mildly retarded. On the AADM scale, Cohen patients had high scores in the positive domains, viz., self-direction, responsibility and socialisation. Maladaptive behaviour, on the other hand, was almost completely absent, except for stereotyped behaviours and odd mannerisms. Withdrawal, sexually aberrant behaviour, untrustworthy and rebellious behaviour as well as antisocial behaviour were rare. These findings are consistent with the cheerful and sociable disposition characteristic of those with Cohen syndrome.
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PMID:Neurological and psychological findings in patients with Cohen syndrome: a study of 18 patients aged 11 months to 57 years. 1056 9

We describe eight members from two large Amish kindreds who share a phenotype characterized by early-onset pigmentary retinopathy and myopia, global developmental delay and mental retardation, microcephaly, short stature, hypotonia, joint hyperextensibility, small hands and feet, common facial appearance, and friendly disposition. Several of the children had intermittent granulocytopenia. The phenotypic occurrence in three siblings coupled with the increased coefficient of inbreeding in the Amish suggested that this disorder is autosomal recessive and due to a single founder allele. Despite similarity to the clinical features of Cohen syndrome, experienced dysmorphologists attending the 23rd David W. Smith Workshop suggested the facial gestalt of the Amish children was inconsistent with this diagnosis. We mapped the locus responsible for these individuals' phenotype to chromosome 8q22-q23, which contains the recently discovered Cohen syndrome gene, COH1. Complete sequencing of the COH1 gene identified a likely disease-causing frameshift mutation and a missense mutation in the Amish patients. A comparison of features among different Cohen syndrome populations with shared linkage to the COH1 locus or known COH1 gene mutations may allow for the determination of improved clinical criteria on which to suspect the diagnosis of Cohen syndrome. We conclude that facial gestalt seems to be an unreliable indicator of Cohen syndrome between ethnic populations, although it is quite consistent among affected individuals within a particular ethnic group. Other features common to almost all individuals with proven COH1 mutations, such as retinal dystrophy, myopia, microcephaly, mental retardation, global developmental delay, hypotonia, and joint hyperextensibility appear to be better clinical indicators of this disorder.
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PMID:Cohen syndrome in the Ohio Amish. 1521 51