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R Lamberts

Publications and source records attributed to R Lamberts.

At least 19 recordsLinked to original sources
PubMed2002

Renin producing neuroendocrine pancreatic carcinoma--a case report and review of the literature.

A 44 year old male patient presented with severe hypertension. The diagnostic work-up revealed elevated levels of plasma renin activity (about 10 times the upper limit of normal) in the presence of normal plasma aldosterone levels and serum potassium concentrations. Renovascular disease was excluded by angiography. Selective renal vein sampling did not show any renin gradient. CT-scans of the abdomen demonstrated normal morphology of the kidneys and adrenals but revealed a big mass in the pancreatic corpus and tail with infiltration of the splenic vein and the presence of enlarged local lymph nodes. The endocrine nature of the pancreatic mass was further supported by a positive octreotide scintigraphy scan. Surgical removal of the tumor by left sided pancreatectomy combined with splenectomy resulted in rapid normalization of elevated renin concentrations as well as blood pressure. Histological examination of the tumor tissue revealed the presence of a neuroendocrine pancreatic carcinoma. Highly (x 70) elevated renin levels were detected by radioimmunoassay in the tumor tissue. To our knowledge this is the first renin-producing neuroendocrine pancreatic carcinoma described in the literature. The present paper describes the case in detail and reviews the available literature on clinical symptomatology, diagnosis and treatment of renin-producing tumors.

Adult↗
PubMed2001

Pancreatic neuroendocrine tumor with extensive vascularisation and parathyroid hormone-related protein (PTHrP)--associated hypercalcemia of malignancy.

We report the case of a 34 year old male presenting with symptomatic hypercalcemia due to excessive PTHrP secretion from a pancreatic neuroendocrine carcinoma with extensive hypervascularization and without any evidence for metastatic disease. In the early phase of the disease conventional chemotherapy with streptozocin and doxorubicin was able to control functional activity as well as tumor growth. However, after 2 years tumor escape was indicated by severe therapy-resistant hypercalcemia. Therapeutic options were reduced due to the excessive tumor vascularization and the patient died from his disease after a short period of intensified therapy. The role of PTHrP in hypercalcemia of malignancy (HHM) and its association with neuroendocrine pancreatic tumors as well as possible therapeutic options are reviewed.

Adult↗
PubMed2001

Effects of very long (up to 10 years) proton pump blockade on human gastric mucosa.

BACKGROUND: Long-term use of proton pump inhibitors (PPI) has been reported to worsen oxyntic mucosa gastritis and the resulting gland atrophy has been considered a potential risk factor for neoplastic changes in the gastric mucosa. AIMS: The present study examines the effect of extended continuous PPI treatment for up to 10 years on the exocrine and endocrine stomach of patients with acid-related diseases of the upper GI tract. METHODS: Biopsies from the antral and oxyntic mucosa taken at regular time intervals were examined for gastritis, atrophy, intestinal metaplasia, Helicobacter pylori and argyrophil cells and correlated to serum gastrin levels. RESULTS: A general amelioration of antral gastritis without relevant changes of atrophy or intestinal metaplasia, contrasted with the worsening of gastritis and gland atrophy seen in the oxyntic mucosa of reflux esophagitis (but not gastric or duodenal ulcer) patients in the presence of H. pylori infection. In association with PPI- induced hypergastrinemia, argyrophil cell hyperplasia (but not dysplasia or neoplasia) developed in the oxyntic mucosa. CONCLUSION: The present results outline the milder pretreatment pattern and higher proneness to PPI-related, H. pylori-restricted worsening of oxyntic mucosa gastritis in reflux esophagitis compared to gastric ulcer or duodenal ulcer patients. In addition, they confirm a substantial safety of long-term PPI therapy as concerns neoplastic changes in the exocrine and endocrine human stomach.

Adolescent↗
PubMed2000

Morphological changes of the human gastric mucosa under long-term proton pump inhibitor therapy and their clinical relevance.

Proton pump inhibitors are potent drugs for the treatment of acid-related diseases. The moderate hypergastrinaemia observed during therapy is a physiological response to low intragastric pH and the increase is limited to the first months of therapy with no further changes thereafter. Reports on endocrine cell changes in the antral mucosa under chronic PPI therapy are controversial and lack clinical relevance. In contrast, in the oxyntic mucosa hyperplastic argyrophil cell changes have been reported, dependent on the degree and duration of hypergastrinaemia, the severity of oxyntic mucosal gastritis, especially atrophy, and the presence of H. pylori infection. Current data do not support a progression from hyperplastic to dysplastic argyrophil cell lesions in humans in the absence of additional genetic factors. Data on the progression of oxyntic gastritis under chronic PPI treatment in comparison to untreated controls could not be confirmed in more recent studies including a well-matched control population. The main factor for gastritis progression is the presence of Helicobacter pylori infection. The bacterium not only causes a chronic inflammation of the gastric mucosa, resulting in atrophy and intestinal metaplasia, but also influences endocrine cell populations involved in the regulation of gastric acid secretion. The clinical benefit of H. pylori eradication in reflux esophagitis patients is still a matter of debate. The complex relations in humans between hypergastrinaemia, (oxyntic) gastritis and atrophy, H. pylori infection, argyrophil cell hyperplasia, and the effects of long-term PPI treatment of acid-related diseases do not allow a quantification of the contribution of each single factor for the observed changes.

Anti-Ulcer Agents↗
PubMed1999

[Initial manifestation of primary intestinal lymphangiectasis as acute abdomen].

HISTORY: A 32-year-old man had ten years previously undergone several laparotomies for recurrent ileus of the small intestine. They revealed severe intestinal oedema and histology showed hyperplasia of the lymphatic system but the aetiology was unclear. After a 10-year interval free of symptoms he presented with marked hypoproteinaemic oedema and exudative enteropathy the cause of which was to be clarified by exploratory laparotomy with excision of lymph nodes and a small section of small intestine. INVESTIGATIONS: Histology revealed intestinal lymphangiectasis with partly hyperplastic lymphoid tissue. Lymphangiography demonstrated several lymph nodes in the region of the aortic bifurcation and renal vessels with a central filling defect. It is thought likely that obstruction to lymphatic flow in this region resulted in oedema of the intestinal wall which caused the recurrent episodes of ileus. DIAGNOSIS: Retrospectively it is assumed that primary intestinal lymphangiectasis was responsible for the initial manifestation of an acute abdomen. For treatment of hypoproteiaemia with human albuminea prot system was implanted. The course was complicated by recurrent inflammation and thrombosis of the port catheter. Because of immune deficiency risk of carcinoma is high in primary intestinal lymphangiectasis. CONCLUSION: Primary intestinal lymphangiectasis, even though a rare condition, should be considered in the differential diagnosis of otherwise unclear acute abdomen.

Abdomen, Acute↗
PubMed1999

[Multiple endocrine neoplasia Type I. Diagnosis and therapy in a case with classical family history].

BACKGROUND: A classical family history, representative of the multiple endocrine neoplasia type I (MEN I) syndrome, is reported to illustrate the clinical manifestations, diagnostic procedures and therapeutic modalities of the various endocrine disorders of this syndrome. DIAGNOSIS: Today genetic analysis clearly identifies gene carriers. In these patients screening of all involved endocrine organs (parathyroid, pituitary, pancreas) at regular time intervals is necessary because also at higher ages additional endocrine manifestations may develop. Due to consequent screening the age at time of diagnosis was reduced by 10 to 20 years. As a consequence the rate of malignancy of pancreatic endocrine tumors which is the limiting factor with regard to long-term prognosis was reduced to about one third. At present it is not known whether this procedure can also increase the survival rate of MEN I patients as could be demonstrated in the MEN II syndrome.

Genetic Testing↗
PubMed1998

Electron-microscopical evidence for heterogeneity of micronodular argyrophil cell growth in man.

Hypergastrinaemia-associated changes of non-antral argyrophil cells in man are of increasing interest, because of the development of potent inhibitors of gastric acid secretion. Using an antibody against chromogranin A, we identified micronodular endocrine cell hyperplasia of the oxyntic mucosa in gastric biopsy specimens of patients with hypergastrinaemia of different backgrounds. Consecutive ultrathin sections were examined at the electron-microscopical level. Endocrine cell types within the (extraepithelial) micronodules closely resembled those in the adjacent mucosa. Micronodules were classified into two groups. The first group was composed of endocrine cells only and predominated in patients with drug-induced hypergastrinaemia and/or chronic gastritis, and in a gastrinoma/MEN I patient. The second group represented "neuroendocrine complexes", showing a close intermingling of non-myelinated nerve fibres with endocrine cells, and was found predominantly in pernicious anaemia. Micronodular argyrophil cell growth in man is therefore heterogeneous and depends on the background of the hypergastrinaemia.

Anemia, Pernicious↗
PubMed1998

Intestinal obstruction, progressive weight loss, and recurrent fever in two patients with mesenteric lesions.

We describe 2 patients who presented with fever and incomplete intestinal obstruction. Previously, both patients had had laparotomies showing unresectable lesions in the root of the mesentery which were histologically diagnosed as sclerosing mesenteritis in the first and mesenteric fibromatosis in the second patient. In spite of aggressive immunosuppressive therapy the first patient deteriorated with high-grade fever and progressive weight loss. Similar symptoms occurred in the second patient. Computed tomographic scanning revealed necrotic lesions in both patients which histologically were found to be an angiocentric T-cell lymphoma in the first and a superinfected necrotizing fibroma in the second patient. It is therefore clinically and radiologically impossible to distinguish between the different causes of mesenteric lesions. Reoperation for further biopsies needs to be considered if such patients do not respond to medical treatment.

Aged↗
PubMed1997

Progression and prognosis of Crohn's colitis.

BACKGROUND: Inflammation refractory to medical treatment frequently characterizes the course of Crohn's colitis, often leading to colectomy and need for a stoma. The influence of disease extent within the colon on prognosis and disease progress over time has not been studied so far. AIMS: We evaluated the disease progress and the long-term outcome in 323 patients with Crohn's colitis followed-up for a mean of 9.8 years. METHODS: The charts were analyzed retrospectively, the mean number of documented examinations was 18.5 per patient. The influence of disease pattern, rectal disease and perianal fistulas on the long-term outcome was evaluated using actuarial methods and independent factor analysis. RESULTS: The probabilities of having pancolitis or rectal disease were 77.1% and 78.8% after 15 years, respectively, and higher in patients with initially left-sided or segmental colitis compared with right-sided colitis. The chance of having perianal fistulas was 43.3% after 15 years. The risk of undergoing resectional colonic surgery was 62.2% after 15 years and higher in the presence of right-sided colitis. The cumulative risk of colectomy was 18.2% after 15 years and higher in patients with pancolitis, left-sided colitis or in the presence of perianal fistulas. The 15-year probabilities of proctectomy (12%) and of having a temporary stoma (21%) were only influenced by the presence of perianal fistulas but not by rectal disease or pattern of colitis. CONCLUSIONS: Most patients with colonic Crohn's disease will eventually have pancolitis but only 20% of them will loose the colon. The proctectomy rate is low despite a high frequency of rectal disease. Perianal fistulas and the presence of total or left-sided colonic involvement are adverse risk factors with regard to preservation of colonic length.

Adult↗
PubMed1996

[Pheochromocytoma-induced multiorgan failure. An internal medicine and surgical emergency].

HISTORY AND CLINICAL FINDINGS: A 66-year-old woman, for 18 months known to have a phaeochromocytoma of the left adrenal, developed sciatica-like pain, headaches, vomiting, diarrhoea and dyspnoea. She had previously refused operative treatment. Physical examination was largely negative. But within a few hours of admission she developed a fever (40.5 degrees C) as well as cardiopulmonary and renal failure. She had to be intubated. INVESTIGATIONS: There was leukocytosis (20,800/microliters) and an increase in creatine kinase activity (136 U/l), in the proportion of isoenzyme CKMB (19 U/l) and the creatine level (1.5 mg/dl). Coronary angiography excluded coronary heart disease. Compared with previous x-rays there was a definite increase in the space-occupying process in the area of the left adrenal. TREATMENT AND COURSE: The life-threatening state required emergency removal of the adrenal tumour. The operation was without complications, but muscle weakness set in, especially proximally, and was slow to regress. No cause was found. CONCLUSIONS: Primary manifestation of a phaeochromocytoma in the form of multiple organ failure is rare and its diagnosis is based on symptoms and radiological demonstration of the tumour, because biochemical data are obscured by the need to give catecholamines therapeutically. If the general condition deteriorates during conservative treatment immediate removal of the tumour is mandatory in view of the otherwise high death rate.

Adrenal Gland Neoplasms↗
PubMed1994

[Hormone dependence of colorectal carcinomas].

The question of a possible hormonal control of colorectal cancer growth can be examined by several different approaches. At the present time epidemiological studies do not give a conclusive answer to this problem. The demonstration of functionally active peptide hormone receptors on colon cancer cell lines may play a role in a subgroup of receptor-positive tumors only. At the present time a classical endocrine mode of action of peptide hormones can be excluded. However, there is a possibility of a "hormonal control" of colorectal carcinomas by so-called "growth factors". In this system the expression of a stimulating growth factor, the demonstration of a specific receptor, the blocking of the effect by receptor antagonists or growth factor antibodies and the demonstration of a functional activity have been fulfilled. The multiple relations between cellular protooncogenes and growth factors on the level of the ligand itself, the receptors, or the intracellular signal transduction connect the process of malignant transformation with hormonal control of growth regulation. This connection might offer a basis for a more causal therapy of colon carcinomas within the near future.

Cell Division↗
PubMed1993

Long-term omeprazole therapy in peptic ulcer disease: gastrin, endocrine cell growth, and gastritis.

BACKGROUND: The effects of chronic drug-induced hypergastrinemia on the exocrine and endocrine stomach are still incompletely understood. Chronic hypergastrinemia in rats and humans is associated with gastric argyrophil cell hyperplasia. METHODS: Seventy-four patients with chronic ranitidine-resistant ulcerations were treated chronically with omeprazole (median observation period 48 [6-84] months). RESULTS: Median fasting serum gastrin levels increased from a pretreatment value of 74-145 pg/mL after 3 months. No further increase was observed thereafter. The finding of atrophic gastritis increased from 1.8% to 20.8% after 5 years. A doubling of the mean argyrophil cell volume density (0.36% vs. 0.74% after 5 years; P < 0.01%) was paralleled by a decrease in the normal endocrine cell growth pattern from 64.3% to 33.3% and an increase in micronodular hyperplasia (8.9% vs. 16.7%). These changes correlated with the severity of corpus gastritis and seemed to be more disease- than drug-related. No statistically significant changes were observed in the antral G- and D-cell volume densities under therapy. CONCLUSIONS: Long-term omeprazole therapy in humans results in moderate hypergastrinemia and a significant argyrophil cell hyperplasia, which are correlated to the grade of corpus gastritis. Because hypergastrinemia and gastritis are closely related, it is difficult to quantitatively assess their respective role in this process.

Adolescent↗
PubMed1992

[Type-2B multiple endocrine neoplasms with diffuse liver metastases as the cause of chronic diarrhea].

During examination before surgical correction of pes valgus a 20-year-old man reported having 3-5 pasty, foul smelling diarrhoeic motions per day for the past 3 years. He was noted to have rather thick lips and Marfan-like body build. Erythrocyte sedimentation rate was 18/34 mm, serum activity of GOT 22.5 U/l, GPT 35.7 U/l. Faecal weight was increased to 640 g/d, fat content to 12 g/d. Serum levels of the carcinoembryonic antigen (2494 ng/ml; normal: < 2.5) and of calcitonin (1,619,760 pg/ml; normal < 100) were elevated. Gastroscopy, partial coloscopy, colon-contrast imaging, ultrasonography and computed tomography of the neck and abdomen, as well as magnetic nuclear imaging of the neck were all normal. But laparoscopy revealed the liver to be infiltrated by small whitish nodules which immunohistologically proved to be metastases of a C-cell carcinoma. Total thyroidectomy was performed and the diagnosis of a C-cell carcinoma of the thyroid confirmed intra-operatively. After the operation the diarrhoea was stopped with codeine (9 mg/d). In case of tumour progression, therapy with octreotide, a somatostatin analogue, will be carried out. The concomitant occurrence of C-cell carcinoma, Marfan-like body build, thick lips and skeletal changes is typical of multiple endocrine neoplasia type 2B, which is caused by a chromosomal defect.

Adult↗
PubMed1992

Inter-relationship between serum gastrin levels, gastric mucosal histology and gastric endocrine cell growth.

The development of gastric enterochromaffin-like (ECL)-cell hyperplasia in humans may be associated with extreme hypergastrinaemia, as occurs in Zollinger-Ellison syndrome (ZES) and pernicious anaemia (type A gastritis). More recently, endocrine cell hyperplasia has been found in all forms of chronic atrophic gastritis and even in cases of focal atrophy. Serum gastrin levels, non-antral gastric endocrine (argyrophil) cell growth, and the severity and type of concomitant gastritis were monitored in 66 unoperated and 8 antrectomized patients with poorly responsive peptic ulcer or reflux oesophagitis during up to 5 years' treatment with high-dose omeprazole, 40 mg daily. A small subgroup of patients (23%) had serum gastrin concentrations of more than four times the normal upper limit. These patients also had hyperplasia of the gastric argyrophil cells. More importantly, the same subgroup of patients had high-grade (atrophic) gastritis. Micronodular hyperplasia of argyrophil cells was significantly more frequent in biopsies showing atrophic gastritis (48%) than in biopsies showing only superficial gastritis (3.6%). It is concluded that, as previously demonstrated in untreated patients with gastric ulcer, the argyrophil cell hyperplasia observed during high-dose omeprazole therapy is related to the progression of chronic atrophic gastritis rather than to serum gastrin levels.

Biopsy↗