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R P Zwierstra

Publications and source records attributed to R P Zwierstra.

At least 19 recordsLinked to original sources
PubMed2000

Limited role of meta-iodobenzylguanidine scintigraphy in imaging phaeochromocytoma in patients with multiple endocrine neoplasia type II.

OBJECTIVE: To compare diagnostic applicability of combined computed tomography (CT) and magnetic resonance imaging (MRI), with that of meta-iodobenzylguanidine (MIBG) scintigraphy in the preoperative localisation of MEN II related phaeochromocytoma. DESIGN: Retrospective study SETTING: University hospital, The Netherlands. MATERIALS: 17 patients with MEN II patients (33 adrenal glands) who were operated on for phaeochromocytoma. MIBG scintigraphy, CT and MRI were used to localize phaeochromocytoma. Histopathologically, an adrenomedullary lesion more than 1 cm in size was classified as a phaeochromocytoma. MAIN OUTCOME MEASURES: Sensitivity, specificity, and diagnostic accuracy of combined CT and MRI and MIBG scintigraphy, compared with histopathological findings. RESULTS: Sensitivity of combined CT and MRI (27 adrenal glands) was 87%, with a specificity of 100% and a diagnostic accuracy of 89%. MIBG scintigraphy (31 adrenal glands) had a sensitivity of 92%, a specificity of only 17%, and a diagnostic accuracy of 77%. CONCLUSION: If unilateral adrenalectomy is done when only one adrenal gland contains a phaeochromocytoma, then MRI should be the method of choice for localising MEN type II related phaeochromocytoma. MIBG scintigraphy can be restricted to those patients in whom MRI does not show a tumour.

3-Iodobenzylguanidine↗
PubMed2000

What are the characteristics of the competent general practitioner trainer?

BACKGROUND: Increasing attention is being given to the training of doctors to become teachers. This does not apply only to the schooling of teachers in undergraduate medical education: at the postgraduate level, general practitioner trainers (GP-trainers) receive special schooling to prepare them for their role. Yet the skills, knowledge and traits that should be expected in the competent GP-trainer have not been elucidated precisely. OBJECTIVES: The aim of this research project is to determine the traits, knowledge and skills required for a competent GP-trainer. METHOD: We used a qualitative method to answer the question. Ten focus-group meetings were held involving three Departments of Vocational Training in The Netherlands. Each group consisted of GP-trainers, GP-trainees or staff members. The transcriptions of these meetings were analysed, resulting in a description of what makes a competent GP-trainer. RESULTS: Five hundred items were obtained from the focus-group meetings, each of which was formulated in the form "A good GP-trainer is/can/knows. ", etc. These items were divided into the following categories: teaching knowledge, teaching skills, teaching attitude and personality traits of the GP-trainer. A competent GP-trainer must understand basic teaching methods and be able to apply this knowledge. The skill to give good feedback was seen as an important asset for a competent GP-trainer, as were observation skills, the skill to analyse and the skill to foster reflection in the trainee. The teaching attitude of a competent GP-trainer is characterized by giving latitude to and having respect for and interest in the trainee, and being available for consultation, while the teaching approach should be individualized. Enthusiasm, flexibility, patience and self-insight were some of the personality traits identified. CONCLUSION: Many characteristics were identified as a result of this research. The next logical step will involve a Delphi consensus procedure to obtain a profile of the competent GP-trainer. This profile will then be suitable in setting the standards for curricula for future GP-trainers.

Attitude↗
PubMed1999

Complications after bilateral adrenalectomy for phaeochromocytoma in multiple endocrine neoplasia type 2--a plea to conserve adrenal function.

OBJECTIVE: To evaluate the complications of the adrenocortical supplementation that is needed after bilateral adrenalectomy for phaeochromocytoma in patients with multiple endocrine neoplasia (MEN) type 2 syndrome. DESIGN: Retrospective study. SETTING: University hospital, The Netherlands. MATERIALS: 28 patients with MEN 2 who underwent total adrenalectomy for phaeochromocytoma between 1972 and 1996. MAIN OUTCOME MEASURES: Perioperative morbidity and mortality, histopathological findings, complications of adrenocortical supplementation therapy. RESULTS: 22 patients had bilateral phaeochromocytomas on histopathological examination (79%) and 6 patients had initially unilateral phaeochromocytomas There was no operative mortality or substantial morbidity except for one splenic injury that necessitated splenectomy. During a mean follow-up period of 14 years (range 1-26) nine patients (32%) had a total of 19 Addisonian crises that necessitated admission to hospital. One patient died of an unrecognised Addisonian crisis. CONCLUSION: Complications of adrenocortical supplementation therapy are considerable, but they can be reduced when unilateral adrenalectomy is done for a unilateral phaeochromocytoma in patients with MEN 2 syndrome, provided that they are carefully followed up.

Addison Disease↗
PubMed1998

[Primary peritonitis due to Streptococcus pneumoniae in childhood].

Three patients, two boys of 5 months and 6 years and one girl aged 4 years, presented with acute abdominal pain, vomiting and fever, suggesting peritonitis. Imaging examinations (abdominal survey roentgenogram and (or) echography), exploratory laparotomy (in two patients) and blood cultures with growth of Streptococcus pneumoniae led to the diagnosis of primary peritonitis. Intravenous antibiotics led to recovery, in one patient complicated by paralytic ileus, which was treated surgically. Primary peritonitis is a rare condition which should be considered in the differential diagnosis of children with an acute abdominal syndrome. Conditions requiring surgery should be excluded by imaging examinations or laparotomy. When the diagnosis is confirmed by paracentesis or laparotomy, antibiotic treatment has to be started.

Abdominal Pain↗
PubMed1998

Oncological implications of RET gene mutations in Hirschsprung's disease.

BACKGROUND: Germline mutations of the RET proto-oncogene identical to those found in the tumour predisposition syndrome multiple endocrine neoplasia type 2A (MEN2A), were detected in 2.5-5% of sporadic and familial cases of Hirschsprung's disease. Some patients with Hirschsprung's disease may therefore be exposed to a highly increased risk of tumours. AIMS: To define clinical use of RET gene testing in Hirschsprung's disease and related patient management from an oncological point of view. METHODS: Sixty patients with Hirschsprung's disease were screened for RET mutations. In three, MEN2A type RET mutations were detected. Case reports for these three patients are presented. RESULTS AND CONCLUSIONS: Only 22 families or sporadic patients with Hirschsprung's disease and MEN2A type RET mutations have been reported. Therefore, it is difficult to predict tumour risk for patients with familial or sporadic Hirschsprung's disease, and their relatives, who carry these mutations. For these mutation carriers, periodic screening for tumours as in MEN2A is advised, but prophylactic thyroidectomy is offered hesitantly. RET gene testing in familial or sporadic Hirschsprung's disease is not recommended at present outside a complete clinical research setting. In combined MEN2A/Hirschsprung's disease families RET gene testing, tumour screening, and prophylactic thyroidectomy are indicated as in MEN2A.

Adult↗
PubMed1997

[Better postoperative pain management in children by introduction of guidelines; a prospective study].

OBJECTIVE: To investigate the influence of recommendations on the quality of postoperative pain management in children. DESIGN: Prospective. SETTING: University Hospital Groningen, the Netherlands. METHOD: After interdisciplinary recommendations on postoperative pain were developed, the quality of postoperative pain management was investigated before implementation (phase I; n = 50 children aged 0-14 who underwent elective surgery), three months after the implementation (phase II; n = 51), and nine months later (phase III; n = 50). Quality was defined by a pain score (for ages 0 to 4 with the 'Children's Hospital of Eastern Ontario pain scale' (CHEOPS) and for ages 4-14 with the Oucher scale) and the prescription of analgetics: kind, dose, frequency, prescription by anaesthetist and doctor on the ward. Pain was scored every 2 hours during the first 24 hours after surgery. A CHEOPS score < or = 6 an Oucher score < or = 50 was defined as adequate; higher scores were defined as inadequate. RESULTS: Pain measurement showed a statistically significant improvement of pain scores in time (phase II and III compared with phase I: odds ratio: 2.5; 95% confidence interval: 1.03-6.00; p < 0.01). Searching for factors that could be responsible for this improvement, like medication, we found no statistically significant differences in everyday practice in phase II and III compared with phase I. However, children who could score their pain by self-report (Oucher) showed the best results in all 3 phases of the study. The youngest children, i.e. less than 6 months old, showed inadequate results during the whole study. The greatest improvement in time during the first 12 hours was seen in the group of children older than 6 months. The recommendations were followed more strictly in younger children, and when continuous morphine was given. CONCLUSION: Pain scores in children improved after the introduction of recommendations on postoperative pain. However, the improvement could not be attributed to factors like medication. Factors like a change in attitude towards pain could be responsible for this change.

Adolescent↗
PubMed1997

[Results of 25-year pheochromocytoma treatment in the Groningen Academic Hospital].

OBJECTIVE: To evaluate 25 years' experience with the localisation techniques, operative management and results of treatment for phaeochromocytoma. DESIGN: Retrospective SETTING: Groningen University Hospital, the Netherlands. METHOD: Localisation results, per- and postoperative morbidity, mortality and treatment results were evaluated in all 59 patients treated for phaeochromocytoma in the period 1970-1995; 41 patients underwent unilateral adrenalectomy, 18 underwent bilateral adrenalectomy. RESULTS: From the introduction of MIBG scintigraphy all tumour sites were correctly diagnosed preoperatively. The transabdominal operation lead to considerable morbidity and minimal mortality. All MEN type 2 patients (n = 5) treated with unilateral adrenalectomy developed phaeochromocytoma in the contralateral gland and needed total adrenalectomy 7 to 14 years after the initial operation. CONCLUSION: A retroperitoneal approach in surgical treatment of phaeochromocytoma is to be preferred. In MEN type 2 patients bilateral adrenalectomy is still mandatory.

Adolescent↗
PubMed1995

[Surgical treatment of lymphadenitis caused by non-tuberculous mycobacteria in children].

A retrospective study was made of 43 consecutive cases of children with the diagnosis of non-tuberculous mycobacterial lymphadenitis treated in our surgical department between 1976 and 1992. In 16 of the 42 children the diagnosis was initially missed and these children elsewhere underwent incision and drainage resulting in a chronic sinus. In 37 children the disease was localized in the head-and-neck area, while in the other 6 inguinal or axillary lymph nodes were involved. All 43 children underwent a regional lymph node dissection with a partial parotidectomy in three. In 5 children recurrent disease developed within 4 months after dissection. The recurrences were all successfully treated with additional surgery. In none of the children did the dissection result in permanent damage of nerves, especially not of the facial nerve. The cosmetic results were good but depended on the possibilities of entering the neck through a cosmetically ideal incision. Early recognition of the disease is of the utmost importance for an adequate surgical and cosmetically desirable result. An aggressive surgical therapy is advocated and will not result in permanent damage provided the surgeon has the technical skill required for neck dissections.

Child↗
PubMed1995

Bilateral split hand/foot malformation and inv(7)(p22q21.3).

A boy with typical tetramelic split hands and feet is described. In addition, there was a large arteriovenous malformation of the right arm. Chromosome studies showed a pericentric inversion of chromosome 7: 46,XY,inv(7)(p22q21.3). Inspection of the extremities and chromosome studies in the parents were normal. This case confirms the suggested localisation of a locus, important for early limb differentiation, on the long arm of chromosome 7, most probably in the chromosomal region 7q21.2-7q21.3. Previously reported cases are reviewed briefly.

Child, Preschool↗
PubMed1991

[Comparison of iodine scintigraphy and computerized tomography in the localization of pheochromocytoma].

A comparison is made of the results of CT scanning and MIBG scintigraphy in the localization of phaeochromocytoma. In 21 out of 24 patients with clinically diagnosed phaeochromocytoma in the University Medical Hospital, Groningen in 1983-1990, MIBG scintigraphy provided accurate localization, while in 16 out of 18 patients with phaeochromocytoma who underwent CT scanning a correct localization was obtained. False negative results were mainly present when lesions were smaller than 2 cm. There were no false positive results. It is concluded that the sensitivity of the two methods in the localization of phaeochromocytoma is about equal. The use of one of the methods rather than of both is advised.

3-Iodobenzylguanidine↗
PubMed1991

[Malrotation?].

Explore the source record for details and available documents.

Digestive System Abnormalities↗
PubMed1991

Teratogenic effects of transplacental transfusion of heterologous antisera simulated in an experimental model using in vitro whole rat embryo culture.

The effects of the transplacental transfusion of heterologous rabbit-anti-rat antiserum (RAR antiserum) and subsequent immunological interaction on the development of 9-10 days old rat embryos (stages 8-10 somites) were studied using an in vitro whole rat embryo culture. Transplacental transfusion was simulated by the embryonic intracardiac microinjection of approximately 0.5 microliter RAR antiserum, followed by an incubation period of 24 and 48 hours. All the tested embryos survived the incubation period. Embryos taken from the incubator after 24 hours showed signs of growth retardation and axial non-rotation, a delayed closure of the neural tube and ear vesicle, and a delayed formation of the foregut. They also had a moderate number of areas with local pathogenetic cell degeneration. Embryos taken from the incubator after 48 hours demonstrated signs of growth retardation and incomplete axial rotation. The formation of the foregut and closure of the neural tube was complete, with the exception of one embryo with a persisting open neuroporus posterior. All embryos displayed a considerable number of areas with local pathogenetic cell degeneration. The intracardiac injection technique is an elegant method to test the effects of teratogens administered directly into the embryonic circulation. The results demonstrate that heterologous antisera have teratogenic potential, believed to be due to an immunological reaction, with a particular sensitivity of the neurectoderm in 9-10 day old embryos.

Abnormalities, Drug-Induced↗
PubMed1990

Enterocolonic fistula due to incarcerated inguinal hernia.

A 2 1/2-year-old boy presented severely underweight and with an extremely distended abdomen. He was born prematurely and at age 6 months had an incarcerated inguinal hernia, which had been treated conservatively. Laboratory investigations at the time of presentation showed evidence of bacterial overgrowth. Barium studies revealed a fistula between the jejunum and sigmoid colon. Resection of the fistula was followed by complete recovery. We suggest that the incarcerated hernia underlies this fistula. Until now, this series of events has not been published.

Barium Sulfate↗