PubMed Health⌕ Search

Biomedical subjects

L T Vlasveld

Publications and source records attributed to L T Vlasveld.

At least 19 recordsLinked to original sources
PubMed2000

Inverse relation between plasma G-CSF levels and neutrophil counts in a patient with autoimmune neutropenia treated with G-CSF.

The pharmacokinetic characteristics of granulocyte colony-stimulating factor (G-CSF) appears to be related to the neutrophil count. We report the case of an 81-year-old male with acquired antibody induced neutropenia treated with G-CSF. This produced a rapid increase in the neutrophil count which appeared to be associated with diminished trough plasma G-CSF levels. Our data appears to indicate that mature neutrophils may play a part in the clearance of G-CSF from plasma.

Aged↗
PubMed2000

A chromosomal abnormality in hyaline vascular Castleman's disease: evidence for clonal proliferation of dysplastic stromal cells.

The pathogenesis of the hyaline vascular variant of Castleman's disease is currently unknown; however, vascular and dendritic cell proliferations are common in this disorder. We report a clonal karyotypic abnormality (46,XX,t(1;16) (p11;p11), del(7)(q21q22),del(8)(q12q22)) in 15 of 20 cells obtained after short-term stromal cultures of a typical case of hyaline vascular Castleman's disease (HVCD). There was no histologic, immunohistochemical, or genotypic evidence of a clonal lymphoid or plasma cell proliferation supporting origin of this aberration from the stromal component, possibly dendritic cells. We re-examined 15 previous cases of HVCD and identified a spectrum of dysplastic changes in the follicular dendritic cells (FDC) of atrophic lymphoid follicles, with some cases showing expansions of FDC networks by CD21 immunostaining. We propose that localized clonal proliferations of stromal elements, particularly follicular dendritic cells, occur in typical HVCD and likely explain the increased incidence of FDC sarcomas in these patients.

Adult↗
PubMed1999

Parathyroid hormone-related protein (PTH-rP)-associated hypercalcemia in a patient with an atypical chronic lymphocytic leukemia.

We describe a patient with an atypical chronic lymphocytic leukemia (CLL) of the mixed cell type with a hypercalcemia due to parathyroid hormone-related protein production by the malignant B cells. On regard of the elevated serum calcium level without overt lytic bone lesions we found elevated serum levels of PTH-rP and demonstrated the presence of PTH-rP on the malignant lymphocytes. PTH-rP-related hypercalcemia in CLL is very rare. The role in PTH-rP in humoral hypercalcemia of malignancy is discussed.

Aged↗
PubMed1998

Metastasis in a benign duodenal stromal tumour.

Gastro-intestinal stromal tumour (GIST) is increasingly recognized as a distinct entity within the group of soft tissue tumours. Mostly, GIST arises from the muscular components of the stromal layer, but the tumour may also originate from the autonomic nerve system, recently designated as gastro-intestinal autonomic nerve tumour (GANT). The majority of GIST is located in the stomach and small intestine; only 4% of GIST is found in the duodenum. Clinical and pathological criteria to differentiate benign from malignant GIST are not well established. Tumour size and mitotic activity are commonly considered as important features, predicting biological behaviour and outcome. It has been suggested that the clinical course of the GANT-type tumours may be more aggressive. We present a case of a radically resected duodenal stromal tumour with benign features, in a young woman, with metastases to the liver and peritoneum occurring 8 years after the initial diagnosis.

Adult↗
PubMed1998

Coincidence of seminoma and sarcoidosis: a myth or fact?

A patient with a stage II seminoma of the testis was treated with a routine orchidectomy and irradiation. One and a half years later enlarged mediastinal lymph nodes were noted. Additional staging showed no other abnormalities and a mediastinoscopy was performed. The initial histologic examination confirmed the clinically suspected diagnosis of sarcoidosis. However, additional immunohistochemical analysis unexpectedly demonstrated that there was also a microscopic relapse of the testis tumor. The literature concerning the co-incidence of non-caseating granulomas and testis tumors is reviewed. It is not clear, whether the granulomas indicate the presence of genuine idiopathic sarcoidosis or whether they reflect a sarcoid-like reaction against tumor antigens. The immunopathogenesis of sarcoid formation and its possible biologic significance in obtaining a spontaneous tumor remission is discussed.

Adult↗
PubMed1997

[Immune thrombocytopenia attributed to norfloxacin].

A 65-year-old woman developed haemorrhagic diathesis due to a profound thrombocytopenia (thrombocyte count: 1 x 10(9)/l) within one week after a 10-day course of norfloxacin (2 x 400 mg/day), prescribed for cystitis. On account of increased megakaryopoiesis in the bone marrow and absence of other causes of thrombocytopenia norfloxacin-induced immune thrombocytopenia was diagnosed. No norfloxacin-dependent antibodies against platelets were detected. Treatment with prednisone (1.5 mg/kg/day) resulted in the normalization of the platelet count within 5 days.

Aged↗
PubMed1997

A case of thymoma-associated autoimmune haemolytic anaemia.

A 50-year-old female presented with severe Coombs-positive haemolytic anaemia. Chest roentgenogram revealed a right-sided paracardial mass in the anterior mediastinum that was proven to be a thymoma. The patient was treated with oral prednisone (1 mg/kg/day) and subsequent thymectomy. Haemolysis did not return although the direct Coombs test remained weakly positive. In reviewing the literature 15 additional cases of thymoma-associated autoimmune haemolytic anaemia were identified.

Administration, Oral↗
PubMed1996

Unchanged pharmacokinetics of etoposide given by intra-arterial hepatic infusion as compared with i.v. infusion.

We investigated the pharmacokinetics of etoposide given to a patient suffering from multifocal liver metastases from an unknown primary tumor. The drug was given either by i.v. infusion or by hepatic arterial infusion (HAI). The calculated pharmacokinetic parameters (mean values +/- SD) were similar after i.v. infusion and HAI, viz., 6.4 +/- 0.7 versus 6.5 +/- 0.2 h for the terminal elimination half-life (t1/2 beta), 98.5 +/- 1.3 versus 101.3 +/- 5.9 mg l(-1) h for the area under the plasma concentration-time curve (AUC), 21.2 +/- 0.3 versus 20.6 +/- 1.2 ml min-1 m-2 for clearance (Cl), 17.7 +/- 1.9 versus 18.1 +/- 2.6 mg/l for the peak concentration, and 11.7 +/- 1.3 versus 11.6 +/- 1.01/m2 for the volume of distribution (Vd), respectively. We therefore conclude that administration of etoposide by HAI does not result in a significantly higher liver extraction. Hepatic extraction of etoposide is determined by the fraction of non-protein-bound (free) drug present. The lack of a difference between the two administration routes suggests that under in vivo conditions the equilibrium between free and bound drug is established before the drug reaches the hepatic arterioles. Consequently, administration by HAI does not lead to an increased exposure of the tumor in the liver to free (active) etoposide. Furthermore, the overall exposure of the liver to total (bound + free) etoposide is increased only from about 100 to 120 mg l-1 h. These results do not favor the use of this more complex route of drug administration in the treatment of (metastatic) cancer located in the liver.

Adult↗
PubMed1996

Low-dose rIL-2-induced remission of disseminated CD30+ anaplastic large-cell lymphoma through reinforcement of presumed T-cell-mediated tumor cell killing, complicated by unilateral drowning of lymphoma-infiltrated lung.

We report on the immuno-oncologic analysis and treatment of a remarkable case of disseminated CD30+ anaplastic non-Hodgkin's lymphoma. Its clinical course was characterized by repeated spontaneous regressions, which were probably due to a T-cell-mediated anti-lymphoma immune reaction, as tumor-infiltrating T lymphocytes were consistently observed in sections of lymphoma lesions and found to express high-affinity receptors for interleukin-2 (IL-2). This marker may be particularly suitable to predict a response to low-dose recombinant IL-2 (rIL-2), as confirmed in this case by prompt lymphoma regression after regional rIL-2 perfusion of a cutaneous lesion and by an impressive overall response to systemic rIL-2 treatment. Despite the very low dose of rIL-2, 600,000 IU/24 h as a continuous i.v. infusion, systemic treatment was complicated by generalized capillary leakage and life-threatening unilateral drowning of the lymphoma-infiltrated left lung.

Adult↗
PubMed1995

Treatment of low-grade non-Hodgkin's lymphoma with continuous infusion of low-dose recombinant interleukin-2 in combination with the B-cell-specific monoclonal antibody CLB-CD19.

Seven patients with low-grade non-Hodgkin's lymphoma were treated with a combination of a murine monoclonal antibody directed against the B-cell-specific antigen CD19 (CLB-CD19), given twice weekly, and continuous infusion of low-dose recombinant interleukin-2 (rIL-2). We demonstrated stable serum CLB-CD19 levels throughout the 12 weeks of treatment, and homing of the antibody into the tumour sites. A variable degree of antigenic modulation was noted. Prolonged treatment resulted in a sustained increase in the number of natural killer cells in the circulation with enhanced cytotoxic capacity, including antibody-dependent cellular cytotoxicity. During the first weeks of treatment, T cell activation occurred in the majority of patients. Toxicity was related to the rIL-2 treatment and consisted of transient constitutional symptoms and a flu-like syndrome without organ dysfunction. A partial remission occurred in one patient, and in another patient who was primarily leukaemic a greater than 50% reduction of circulating B cells was noted. An antitumour effect occurred early during treatment and could not be related to rIL-2-induced modulation of natural killer cell or T lymphocyte activation.

Adult↗
PubMed1995

Pilot study of a high-dose carboplatin-based salvage strategy for relapsing or refractory germ cell cancer.

Eleven patients with germ cell cancer relapsing from a complete remission and 7 patients with refractory germ cell cancer and/or an unresectable partial remission received salvage chemotherapy with one to two courses of carboplatin (800 mg/m2) and etoposide (500 mg/m2 on days 1, 3, and 5), followed by either one or two courses of carboplatin (1600 mg/m2), cyclophosphamide (6 g/m2), and thiotepa (480 mg/m2) divided over 4 days with autologous bone marrow transplantation and/or peripheral stem cell support. Eight of 11 relapsing patients (73%) were salvaged (with a follow-up of 21+ to 56+ months), but only 1 of the 7 refractory patients survived (34+ months). The high-dose carboplatin-based salvage regimen is feasible and deserves further evaluation in patients relapsing from a complete remission. Even more intensive treatment strategies may be required to salvage patients who are refractory to standard doses of platinating agents.

Adult↗
PubMed1994

[Cortical blindness during treatment with cyclosporin].

A 40-year-old man developed cortical blindness during cyclosporin treatment shortly after an allogeneic bone marrow transplantation for chronic myeloid leukaemia. At that time the patient had a therapeutic cyclosporin blood level (226 ng/ml), but a low serum magnesium level and a marginally decreased serum cholesterol level. In addition the patient had hypertension, headache and paraesthesia in the oral, palmar and plantar areas. Vision was fully recovered after discontinuation of the cyclosporin treatment and correction of the hypomagnesaemia. Eighteen cases of cortical blindness during cyclosporin treatment are now known in the literature. Hypomagnesaemia appears to be implicated in the pathogenesis.

Adult↗