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Biomedical subjects

C Schaap

Publications and source records attributed to C Schaap.

At least 19 recordsLinked to original sources
PubMed2000

Cri du chat syndrome: changing phenotype in older patients.

The cri du chat syndrome or 5p deletion syndrome is a well-delineated clinical entity and has an incidence of 1/50,000 in newborn infants. A de novo deletion is present in 85% of the patients. Ten to 15% are familial cases with more than 90% due to a parental translocation and 5% due to an inversion of chromosome 5. Although the size of the deleted segment varies, the critical segment that is deleted in all patients appears to be 5p15.2. The clinical picture is well known in younger patients and includes the typical high-pitched cry, psychomotor retardation, microcephaly, growth rate failure, and craniofacial abnormalities including round face, hypertelorism, broad nasal bridge, downward slanting palpebral fissures, and micrognathia. With advancing age, the clinical picture becomes less striking. We present seven patients with 5p deletion syndrome, who were between age 16 and 47 years. Comparing their phenotype at several ages, a change of their phenotype was noted. Some of the clinical characteristics became more evident such as long face, macrostomia, and scoliosis. All patients were severely or profoundly mentally retarded except one patient who was mildly mentally retarded. The diagnosis was difficult to make in some of the patients who were first seen at an older age. In some of them, the craniofacial appearance resembled that seen in Angelman syndrome. Most patients had periods of destructive behavior, self mutilation, and aggression. The clinical diagnosis should be confirmed as soon as possible with cytogenetic investigation to provide specific support, prevention, and treatment of complications. Therefore, it is important to perform follow-up studies in young children to determine their outcome after infant-stimulation programs.

Adolescent↗
PubMed1999

Novel KCNQ1 and HERG missense mutations in Dutch long-QT families.

Congenital long QT syndrome (cLQTS) is electrocardiographically characterized by a prolonged QT interval and polymorphic ventricular arrhythmias (torsade de pointes). These cardiac arrhythmias may result in recurrent syncopes, seizure, or sudden death. LQTS can occur either as an autosomal dominant (Romano Ward) or as an autosomal recessive disorder (Jervell and Lange-Nielsen syndrome). Mutations in at least five genes have been associated with the LQTS. Four genes, encoding cardiac ion channels, have been identified. The most common forms of LQTS are due to mutations in the potassium-channel genes KCNQ1 and HERG. We have screened 24 Dutch LQTS families for mutations in KCNQ1 and HERG. Fourteen missense mutations were identified. Eight of these missense mutations were novel: three in KCNQ1 and five in HERG. Novel missense mutations in KCNQ1 were Y184S, S373P, and W392R and novel missense mutations in HERG were A558P, R582C, G604S, T613M, and F640L. The KCNQ1 mutation G189R and the HERG mutation R582C were detected in two families. The pathogenicity of the mutations was based on segregation in families, absence in control individuals, the nature of the amino acid substitution, and localization in the protein. Genotype-phenotype studies indicated that auditory stimuli as trigger of cardiac events differentiate LQTS2 and LQTS1. In LQTS1, exercise was the predominant trigger. In addition, a number of asymptomatic gene defect carriers were identified. Asymptomatic carriers are still at risk of the development of life-threatening arrhythmias, underlining the importance of DNA analyses for unequivocal diagnosis of patients with LQTS.

Cation Transport Proteins↗
PubMed1999

Predictive DNA testing for multiple endocrine neoplasia 2: a therapeutic challenge of prophylactic thyroidectomy in very young children.

BACKGROUND: Patients with multiple endocrine neoplasia (MEN) type 2 are at risk for early medullary thyroid carcinoma (MTC). Recently, the cloning of the ret oncogene has made it possible to identify patients at risk for MEN 2 syndrome with a high degree of reliability before presenting any symptoms. METHODS: Children of families with MEN 2 were screened genetically if one of the parents was a known gene carrier of the RET proto-oncogene. If they were carriers, thyroidectomy was performed. RESULTS: The authors report five children with MEN 2 who underwent prophylactic thyroidectomy irrespective of the results of calcitonin screening tests after genetic screening had shown that they were carrier of the RET proto-oncogene. Apart from a temporary hypocalcemia in one, the operations were uneventful. Pathology results showed MTC in three children of one family with MEN 2A at age 2, 3, and 6 years. In two families with MEN 2B the thyroidectomy specimen showed bilateral MTC in a 1-year-old and a 3-year-old child. CONCLUSIONS: These findings show that MTC occurs at very young age in children with MEN 2. The authors advocate performing prophylactic thyroidectomy in the first year of life in children with MEN 2B and at age 2 years in children with MEN 2A to obtain an optimal cure rate.

Carcinoma, Medullary↗
PubMed1999

Two sibs with microcephaly, hygroma colli, renal dysplasia, and cutaneous syndactyly: a new lethal MCA syndrome?

We report two sibs of Turkish descent with multiple congenital anomalies including severe microcephaly, hygroma colli, cystic renal dysplasia, and bilateral cutaneous syndactyly of toes IV-V. In addition, the second sib presented with bilateral fusion of the eyelids, a bicornuate uterus, and clitoromegaly. The parents are first cousins, which suggests autosomal recessive inheritance. In reviewing previously published reports, several cases were found with cerebral, renal, and digital anomalies as the main features. Several of the additional symptoms present in the second sib were suggestive of Fraser syndrome, but the severe microcephaly in both sibs is unusual. The differential diagnosis is discussed, including the possibility of an entirely new entity in the broad spectrum of syndromes with cerebral, renal, and digital anomalies.

Abnormalities, Multiple↗
PubMed1996

Familial medullary thyroid carcinoma: not a distinct entity? Genotype-phenotype correlation in a large family.

BACKGROUND: Multiple endocrine neoplasia type 2A (MEN 2A) is a hereditary syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma, and hyperparathyroidism. Familial MTC (FMTC) is characterized by MTC only. Both MEN 2A and FMTC are caused by germline mutations of the RET proto-oncogene. PURPOSE: To assess genotype/phenotype correlations, large families have to be examined periodically over a long period using an extensive screening program. PATIENTS AND METHODS: Since 1973, we screened a large family with hereditary C cell carcinoma for MTC, pheochromocytoma, and parathyroid disease by clinical tests and imaging methods. A germline codon Cys618 to Ser mutation in the RET proto-oncogene was recently identified in this family. The disease phenotype associated with this mutation was compared with that of Cys634 mutations in some other large MEN 2A families. RESULTS: The distinct course of disease in the family described here is similar to that in other FMTC families and MEN 2A families with a Cys618 mutation of the RET gene, but clearly different from that in families with a Cys634 mutation. The frequency of pheochromocytomas and parathyroid disease is clearly lower, whereas cure rates and life expectancy are higher. However, in families with a Cys618 mutation, pheochromocytoma and parathyroid disease do occur. CONCLUSION: In FMTC families with cysteine codon mutations of the RET proto-oncogene, screening for other endocrinopathies is mandatory, since these may not be MTC-only families. Therefore, we suggest that MEN 2A families should not be subclassified into MEN 2A and FMTC, but rather according to their specific mutation in the RET protein (i.e., for this family MEN 2A RET C618S).

Adrenal Gland Neoplasms↗
PubMed1995

Three mildly retarded siblings with congenital cataracts, sensorineural deafness, hypogonadism, hypertrichosis and short stature: a new syndrome?

We report three male siblings with mild mental retardation, congenital cataract, sensorineural deafness, hypogonadism, hypertrichosis and short stature. This combination has not been previously reported and we suggest this is a new syndrome. Although X-linked recessive inheritance cannot be fully excluded, we favour autosomal recessive inheritance because of parental consanguinity.

Adolescent↗
PubMed1995

A genetic diagnostic survey in an institutionalized population of 116 moderately to severely retarded male patients: the Rekem experience.

In this paper we report the results of a genetic-diagnostic survey of 116 institutionalized male patients who were moderately to severely retarded. In 31 patients (26.7%) a constitutional cause of their mental impairment was found: chromosomal abnormalities in 11 patients (9.5%), Mendelian disorders in 16 (13.8%), of which 8 fragile X patients (6.9%), and a MCA/MR syndrome in 4 patients (3.4%). Acquired forms of mental retardation occurred in 26 patients (22.4%): CNS-dysfunction due to pre-, peri- or postnatal causes were most likely in 18 patients (15.5%), while infections played a major role in 8 (6.9%). In 59 patients (50.9%) not etiological diagnosis could be made.

Adult↗
PubMed1993

[A Dutch family with hereditary joint symptoms; multiple epiphyseal dysplasia].

Multiple epiphyseal dysplasia is a rare disease with autosomal dominant heredity which affects the epiphyseal ends of long bones; it leads to severe destruction of the joints. A large Dutch family with multiple epiphyseal dysplasia is described with manifestations of clinical disease predominantly in the lower extremities.

Adolescent↗
PubMed1993

Do patients suffering from obsessions alone differ from other obsessive-compulsives?

The aim of this study was to determine whether a group of 48 patients with obsessions and compulsions differed from a group of 26 patients with obsessions alone, on the basis of demographic variables, variables relating to obsessive-compulsive neurosis, psychological variables and treatment outcome. It was found that they differed significantly in the following areas: marital status, level of education, age at onset of complaints, psychoactive medication taken when admitted for treatment, severity of obsessive-compulsive complaints, depression and intelligence. No difference was found as far as treatment outcome was concerned. Patients suffering from obsessions alone, would appear to form a distinct sub-group within the group of obsessive-compulsive patients as a whole.

Adult↗
PubMed1993

The heterogeneity of schizophrenic information processing and negative versus positive symptoms.

In this study, 20 schizophrenic patients were subdivided into a schizophrenia group with positive symptoms (N = 11) and a schizophrenia group with negative symptoms (N = 9) by Andreasen's rating scales: the Scale for the Assessment of Negative Symptoms and the Scale for the Assessment of Positive Symptoms. These groups were compared with 17 normal controls and 17 subjects with a closed head injury. Indices of information processing derived from Coglab, a multiparadigmatic cognitive test battery developed by Spaulding et al., were used for comparison. The "negative" schizophrenia subjects were characterized by a more pervasive deficient information-processing capacity than the "positive" schizophrenia subjects. The deficits both groups had in common were, however, not of equal severity. The closed head injury group, who served as an indirect control for the presumed generalized deterioration in the negative schizophrenia group, did not compare very well to this latter group. The results are discussed in relation to the question of whether the information-processing deficiencies stem from a single causal process, or whether these deficiencies are independent and associated with many etiological pathways.

Adult↗
PubMed1992

McKusick-Kaufman syndrome: the diagnostic challenge of abdominal distension in the neonatal period.

We report a newborn girl with McKusick-Kaufman syndrome who presented at birth with severe life-threatening abdominal distension due to hydrometrocolpos. In children with polydactyly and cystic masses in the lower abdomen should hydrometrocolpos be especially considered. Ultrasonography is of great value in the correct assignment of lower abdominal tumours, but should be completed by vagino(cysto)scopy when hydrometrocolpos is suspected.

Abnormalities, Multiple↗
PubMed1992

Do drop-outs differ from successfully treated obsessive-compulsives?

The most common reasons given by patients for dropping out of treatment are: environmental constraints, dissatisfaction with services and that they no longer need help. In this study two groups of patients suffering from obsessive-compulsive disorders are compared. The drop-outs' reasons for terminating treatment are compared with the comments of patients who completed the therapy successfully. Drop-outs differ from successfully treated OCD's in five respects: they appear to be less obsessive-compulsive; they have more discongruent treatment expectations; they are more critical of the therapist; they experience less anxiety in carrying out homework assignments; they less frequently come under pressure from people close to them.

Adaptation, Psychological↗
PubMed1992

Opitz-C syndrome: on the nosology of mental retardation and trigonocephaly.

We report on two patients with a complicated form of trigonocephaly. The first patient has the Opitz-"C"-trigonocephaly syndrome. The second patient had initially a delayed motor development, but finally attained normal intelligence. A review of 22 patients with Opitz-C syndrome from the literature is presented. Most of the typical facial dysmorphism can be regarded as part of a trigonocephaly "sequence" rather than presenting characteristic features of a syndrome. More specific are the intra-oral anomalies, abnormally modelled ears, cardiac anomalies and neonatal hypotonia. All surviving patients are severely retarded. Since almost all patients are sporadic cases we suggest that the "C"-syndrome is a cytogenetically yet undetectable microdeletion syndrome.

Abnormalities, Multiple↗
PubMed1991

The effects of a somatostatin analogue on the metabolism of an infant with Beckwith-Wiedemann syndrome and hyperinsulinaemic hypoglycaemia.

Hypoglycaemia is a frequent finding during the neonatal period and may be due to insulin overproduction. Patients with Beckwith-Wiedemann syndrome have reduced numbers of somatostatin-producing cells and decreased extractable somatostatin. In this study the effect of long-acting somatostatin (SMS201-995) on the glucose and insulin levels in an infant with Beckwith-Wiedemann syndrome and hyperinsulinaemic non-ketotic hypoglycaemia is described. SMS201-995 lowered basal insulin levels while maintaining normal glucose and insulin homeostasis. During fasting however, both glucose levels declined rapidly whereas insulin levels did not. The absence of both ketosis and elevated levels of free fatty acids and lactate during hypoglycaemia, as observed in our patient, are important diagnostic clues since the insulin levels themselves may sometimes be only slightly elevated.

Beckwith-Wiedemann Syndrome↗
PubMed1991

Verbal analysis of doctor-patient communication.

A microscopic analysis of doctor-patient communication in the general practitioner's surgery is presented. Verbatim transcripts of 85 medical interviews, audiotaped in a natural situation were analysed. The effects of type of complaint, patient gender and physician gender on the process of verbal communication were assessed. This study focused upon the relational aspects of communication, using Stiles' Verbal Response Mode coding system (VRM), and, to a limited extent, upon the content of patient's complaints--whether they were primarily somatic or of a psychosocial nature. The hypothesis of an asymmetrical relation between physician and patient was confirmed. Results partially confirmed the hypothesis that interviews of psychosocial patients take more time than those of somatic patients. There was also some evidence that psychosocial patients try to exert more control over the conversation as compared to somatic patients. Male and female patients differed in the way they elaborated their complaints. When telling their complaints, women referred more to persons (family, friends, colleagues) than did men. In case of male GP's, the interviews of female patients took more time than those of male patients. The largest differences were between male and female physicians. In agreement with the hypothesis males were more imposing and presumptuous (giving more advisements and interpretations). Female GP's were more attentive and non-directive (giving more subjective and objective information and acknowledgements). The medical interviews of female GP's took more time than the interviews of their male colleagues. The results are discussed in the light of theoretical concepts of harmony and discrepancy with respect to doctor-patient communication and theories about gender differences.

Adolescent↗