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A study of the cellular and humoral immune response in patients with myelofibrosis.

There was evidence of impaired cellular immunity in 10 patients with myelofibrosis. In-vitro lymphocyte transformation with phytohaemagglutin, concanavalin A, and dinitrochlorobenzene skin reaction were diminished. Signs of impaired humoral activity were also found, the primary response to alpha-Helix pomatia haemocyanin being impaired, particularly in the immunoglobulin-A class. Moreover three patients had a benign paraproteinaemia. Immunecomplexes (IC) could be demonstrated with various test systems. The indirect granulocyte phagocytosis test was positive in 50%, the C1q-binding in 70% and the polyethylene glycol precipitation test in 50%. In most patients complement levels were normal, although the patient with the most advanced disease had low C3A, C3 and C4 levels accompanied by high levels of IC. No correlation could be shown between impaired immune response or levels of IC when they were related to spleen diameter or degree of anaemia. Some relation however existed between disturbed immune response and IC when they were related to time elapsed since diagnosis. It is suggested that the impaired immune response is the result of primary bone marrow disease and that the presence of IC may reflect the extent of fibrosis.

Antibody Formation↗

Trisomy 13 in bone marrow cells in acute myelocytic leukemia and myelofibrosis.

We have identified trisomy 13 in two additional patients with hematologic malignancies involving the hematopoietic stem cell: a 75-year-old female with acute myelocytic leukemia and a 64-year-old female with agnogenic myelofibrosis and myeloid metaplasia. Chromosome analysis of the direct bone-marrow preparation showed 100% of cells with trisomy 13 in the first and 10% of cells in the second. We also previously reported a patient with Ph1 negative chronic myelogenous leukemia in whom 100% of the marrow cells showed an identical trisomy. The probability of finding three such patients in our case material was calculated to be 0.05--0.08, implying that trisomy 13 may be another nonrandom chromosomal aberration associated with malignancies of hematopoietic pluri-potent stem cell.

Aged↗

Portal hypertension secondary to myelofibrosis: a study of three cases.

BACKGROUND: In patients with idiopathic myelofibrosis (IM), portal hypertension (PHT) without thrombosis of the hepatic or splenoportal veins is infrequent. OBJECTIVE: To ascertain the mechanisms responsible for the development of PHT in IM and their therapeutic implications. PATIENTS AND METHODS: Color Doppler ultrasound with portal flow quantification, hepatic hemodynamic studies, and histological examinations of the liver biopsies were performed in three IM patients with PHT in whom hepatic and splenoportal thrombosis were ruled out. RESULTS: Two patients showed sinusoidal PHT (increased hepatic venous pressure gradient), normal portal flow, and massive myeloid metaplasia of the liver. Transjugular intrahepatic portosystemic shunt (TIPS) was indicated for variceal bleeding and ascites unresponsive to medical therapy, and resulted in an adequate control of these PHT complications. At the time of TIPS placement, direct portal pressure measurement showed a marked presinusoidal component in the PHT. A third patient died as a consequence of the IM before treatment of PHT could be instituted. This patient showed an extremely increased portal flow and lesser hepatic infiltration. CONCLUSIONS: IM patients with PHT might have a marked presinusoidal component contributing to PHT that is underestimated by hepatic vein catheterization. Treatment of the complications of PHT might not differ from that of patients with cirrhosis.

Aged↗

Polycythaemia vera-transformation to myelofibrosis and subsequent reversal.

A woman aged 67 who developed polycythaemia vera 21 years ago has been seen regularly since the diagnosis was first made. She was treated initially with pyrimethamine and then for 10 years by repeated venesections. After a 4 year period when her myeloproliferative disease was considered to be transitional a complete transformation to myelofibrosis occurred. She was treated by splenic irradiation and later with alkylating agents in an attempt to give her symptomatic relief from massive splenomegaly. Repeated and massive haemorrhage from gastro-oesophageal varices was treated initially by percutaneous transhepatic sclerosis of the gastro-oesophageal collateral vessels. A subsequent dacron mesocaval jump graft operation was successful in preventing further haematemesis and melaena. During the last year transformation back to polycythaemia vera has occurred. The evolution of her myeloproliferative disease has been fully documented by detailed blood counting, bone marrow aspirates and trephine biopsies, blood volume studies and other radioisotope investigations including the quantitation of functional erythropoietic tissue with 52Fe.

Aged↗

The effect of acetyl salicylic acid and dipyridamole on thromboembolic complications in splenectomized patients with myelofibrosis.

The effect of combined treatment with acetyl salicylic acid and dipyridamole on thrombic phenomena was studied in splenectomized patients with an aggressive form of myelofibrosis. 3 of these patients had thrombotic episodes, shortened platelet survival and an abnormal platelet aggregation pattern. The treatment with antiplatelet drugs resulted in a decreased platelet utilization as evidenced by clinical improvement and an increasing platelet concentration.

Aged↗

Massive platelet transfusion after splenectomy in a case of myelofibrosis.

A patient with myelofibrosis complicated by massive splenomegaly underwent splenectomy to alleviate the increasing transfusion requirements and iron overload. The platelets exhibited qualitative defects pre-operatively. Following splenectomy the patient bled profusely and required massive blood and platelet transfusions. The postoperative haemorrhage was controlled by giving sufficient platelets to normalize the platelet aggregation.

Blood Platelets↗

Primary myelofibrosis with myeloid metaplasia and cytogenetically abnormal clones in 2 children with Down's syndrome.

2 children with Down's syndrome showed severe anaemia, leucocytosis with blastic cells, thrombocytopenia and hepatosplenomegaly. Bone marrow aspirations were near-dry tap and marrow biopsy revealed primary myelofibrosis with myeloid metaplasia (MMM). Their course was short with a blood picture similar to that of leukaemia. They expired 2 months and 21/2 months after diagnosis, respectively. The cases were thought to represent an acute childhood variant of MMM. Cytogenetic study of circulating white cells by 24 h culture without phytophaemagglutinin stimulation revealed aneuploidy in both cases, the first case showing marked aneuploidy with a predominant karyotype of 50,XX,+8,+19,+19,+21 and the second case a mosaic of 47,XX,+G/48,XX+G,+G. The karyotype of phytohaemagglutinin stimulated lymphocytes was 47,XX,+G in both cases. These findings suggest that the abnormal karyotypes are those of circulating blastic cells which are abnormal clones of haematopoietic cells responsible for MMM. In Down's syndrome, MMM might not be so rare as reported.

Bone Marrow↗

Defective platelet aggregation and increased platelet turnover in patients with myelofibrosis and other myeloproliferative diseases.

In 9 patients with myeloproliferative diseases (MPD) (6 with myelofibrosis, MF, 1 with Ph1 positive chronic granulocytic leukaemia, CGL, 1 with primary eosinophilia, PE, 1 with pre-leukaemia syndrome, preL) collagen, epinephrine, and ADP-induced aggregation, N-ethylmaleimide-induced malondialdehyde (MDA) production, beta-thromboglobulin (beta-TG) plasma levels, and platelet turnover were studied. Collagen-induced aggregation was found to be normal in 7 patients, absent in 1, and reduced in 1. In all but 3 patients, aggregation with ADP was markedly reduced. Epinephrine-induced aggregation was decreased in 7 patients. No difference was found between mean MDA production in MPD (3.21 +/- 0.50 nmol/10(9) PLTs) and in control group of 21 normal subjects (3.04 +/- 0.26 nmol/10(9) PLTs). Mean beta-TG levels were significantly higher (P less than 0.01) in MPD patients (165.00 +/- 28.29 ng/ml) than in healthy controls (81.76 +/- 14.63 ng/ml). Mean platelet production half-time was significantly shorter in MPD (2.48 +/- 0.24 d) than in the control group (3.43 +/- 0.17 d), after adjustment for age by covariance analysis (P less than 0.005). Our data do not indicate an abnormal prostaglandin synthesis and are consistent with the hypothesis that a disseminated intravascular platelet aggregation might take place in MPD patients.

Adult↗

Intracranial myeloid metaplasia in myelofibrosis.

In a man aged 62 years with a 14-year-history of polycythaemia vera progressing into a myelofibrotic stage symptoms and signs of an intracranial tumour with increased intracranial pressure developed. CT scan as well as angiography of the right internal carotid artery revealed richly vascularized masses within the meninges. The patient died in endocarditis and progressive heart failure and at autopsy the intracranial masses were shown to be due to meningeal myeloid metaplasia. The literature is reviewed and it appears that myeloid metaplasia within the central nervous system might be more common than has been hitherto anticipated. A CT scan is to be recommended in myelofibrosis whenever symptoms and signs suggesting intracranial disease are present.

Brain Diseases↗

Clonal karyotype abnormalities in erythroid and granulocyte-monocyte precursors in polycythaemia vera and myelofibrosis.

To determine whether clonal karyotype abnormalities seen in myeloproliferative disorders originate in cells of only one or of more blood cell lines, committed erythroid and granulocyte-monocyte progenitor cells were cultured in vitro by the methyl cellulose assay, and chromosome studies were carried out on the colonies. 3 patients were studied, 1 with polycythaemia vera and 2 with myelofibrosis, which was preceded by polycythaemia vera in 1 of the cases. All analysable karyotypes from both erythroid and granulocyte-monocyte colonies in every patient showed the clonal karyotype aberration which had been demonstrated in the bone marrow or blood of the patient. This finding is evidence of the involvement of a multipotent stem cell in the clonal proliferation of these diseases.

Aged↗

Transition of myelofibrosis to polycythaemia vera.

A case of typical myelofibrosis with a huge spleen is described in a 62-year old man. During the subsequent 2-year follow-up, a clinical picture of polycythaemia vera with pancytosis and disappearance of the marrow fibrosis was observed. The pancytosis necessitated treatment with busulphan and frequent phlebotomies. The transformation was associated with prednisone treatment for a suspected haemolytic state. During this treatment, the spleen no longer became enlarged on clinical palpation, although it was still enlarged at post mortem examination, but much less than 2 years earlier.

Anemia, Hemolytic, Autoimmune↗

Polycythaemia following splenectomy in myelofibrosis with myeloid metaplasia. A reorganization of erythropoiesis.

3 patients with myelofibrosis with myeloid metaplasia were splenectomized because of anaemia and disturbing splenomegaly. In the course of the 6 months following splenectomy, a polycythaemia developed. Erythrokinetic studies demonstrated that in all cases a reduction in plasma volume and an increase in red cell volume was obtained. Total erythropoiesis decreased along with normalization of ineffective erythropoiesis and peripheral haemolysis. The reappearance of an erythropoietic activity measured over the sacrum was a constant finding, while in 1 patient, a depression of activity over the liver was observed. The new distribution and organization of erythropoiesis in the splenectomized patients is hypothesized as being due to the removal of the influence of an enlarged spleen on erythropoietic organs.

Aged↗

Spongy lymphoid myelofibrosis as a predictor of hairy cell leukaemia or a variant of hairy cell leukaemia without hairy cells?

8 patients with clinical and haematological features suggestive of hairy cell leukaemia are described. During their initial illness morphologic and cytochemical evidence of hairy cell leukaemia were lacking in all but 2 patients. A common highly characteristic histopathologic finding was reticulin fibrosis in the bone marrow, present in all patients at first presentation. The term spongy lymphoid myelofibrosis is proposed for such cases, which may represent a variant type of hairy cell leukaemia or an early stage of the disease.

Aged↗

Circulating immune complexes in myelofibrosis.

17 patients with idiopathic myelofibrosis were studied for the occurrence of circulating immune complexes (IC), using a polyethylene glycol complement consumption and a polyclonal rheumatoid factor inhibition assay. In 13 patients complement C3d was determined by rocket immunoelectrophoresis. Circulating IC were detected in 6 patients and were primarily found in patients with short duration of disease from time of diagnosis. The median duration of the disease in IC-positive patients was 4 months, compared to 12 months in the IC-negative group (P less than 0.05). 9 of the 13 patients investigated had increased levels of plasma C3d. However, there was no correlation to the occurrence of IC. It is concluded that circulating IC may take part in an immune-mediated bone marrow damage. This may involve deposition of IC in the bone marrow with secondary inflammation responsible for the development of bone marrow fibrosis.

Adult↗

Granulocytic and stromal progenitors in the bone marrow of patients with primary myelofibrosis.

Quantitative and qualitative changes in granulocyte-macrophage (CFU-GM) and fibroblast colony-forming cells (CFU-F) were studied in 7 patients with primary myelofibrosis (MF). Marrow cells were collected from bone biopsy specimens after treatment with collagenase. The number of CFU-GM correlated with the amount of haemopoietic tissue noted in the bone marrow histology and ranged between 0-400/mg of bone. CFU-F were increased in 2 patients with moderate fibrosis. Circulating CFU-GM were increased in all patients studied (169-3749/ml of blood). There was no significant correlation between the number of CFU-GM in the bone marrow and that in the blood. Cytochemical studies showed a high incidence in eosinophil progenitors in the bone marrow and especially in the blood of patients with MF. These data suggest a functional abnormality of myeloid progenitors in this disease.

Aged↗

Megakaryoblastic transformation of myelofibrosis with expression of the c-sis oncogene.

We describe a case of primary myelofibrosis which terminated in an acute megakaryoblastic leukaemia with massive marrow fibrosis and osteosclerosis. The megakaryocyte lineage of the terminal phase was confirmed by ultrastructural and surface marker studies of the blast cells. The leukaemic phase was associated with the presence of large numbers of progressively more immature megakaryocyte progenitors in the peripheral blood. The expression of c-sis mRNA in these blast cells was significantly higher than in normal mononuclear cells. Activation of the c-sis protooncogene leading to increased production of platelet-derived growth factor could be related to the progressive fibrosis observed.

Adult↗

Effect of splenectomy on circulating haematopoietic progenitors in myelofibrosis.

The effect of splenectomy on peripheral blood CFU-GM and BFU-E numbers was studied in a patient with myelofibrosis. The numbers of CFU-GM and BFU-E were twice as high in the splenic venous blood as in the peripheral blood. The number of CFU-GM in peripheral blood decreased to 20% and that of BFU-E to 7% of the presplenectomy level at 1 wk after the operation. The progenitor numbers recovered to reach the presplenectomy level within 4-6 w after splenectomy. This effect of splenectomy was different from that seen in 3 patients with Hodgkin's disease, in whom increased numbers of progenitors were observed after a small initial notch.

Aged↗

Alpha interferon in the treatment of symptomatic myelofibrosis with myeloid metaplasia.

2 patients with myelofibrosis and myeloid metaplasia had symptomatic splenomegaly and were treated with interferon alpha-2c (IFN alpha-2c). The splenic pain and pressure symptoms disappeared, accompanied by a decrease in the size of the spleen. However, the peripheral blood count worsened and no improvement in the bone marrow fibrosis could be observed.

Humans↗