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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The possible role of phagocytosis of circulating immune complexes by neutrophils in the production of the neutropenia of Felty's syndrome has been investigated. Normal neutrophils phagocytosed massive inclusions from the sera from twelve of fifteen patients with Felty's syndrome when incubated with these sera. Such inclusions were phagocytosed from only three of fifteen patients with seropositive RA who did not have Felty's syndrome. Normal neutrophils were more effective than patient neutrophils with regard to phagocytosis of inclusions from the patients' serum suggesting a defect in phagocytic function of Felty's neutrophils. The titre of granulocyte-reactive antinuclear antibodies did not appear to be related to the degree of neutropenia. The data suggest that phagocytosis of circulating immune complexes by neutrophils may interfere with the function of these cells in combating infection and also render them susceptible to removal from the circulation thus leading to the development of neutropenia.
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PMID:Phagocytosis of immune complexes by polymorphonuclear leucocytes in patients with Felty's syndrome. 19 98

The mechanism of neutropenia in Felty's Syndrome (FS) was tested. The suppressor capacity of mononuclear cells from patients with FS on normal bone marrow granulopoiesis was tested by the in vitro colony forming unit in culture assay. Peripheral blood, bone marrow, and spleen cells from FS patients with marked neutropenia (less than 1,000 neutrophils/mm3) suppressed the colony forming unit in culture of normal bone marrow. Cells from rheumatoid arthritis patients without neutropenia, cells from patients with drug-induced neutropenia without rheumatoid arthritis, or plasma from FS patients failed to suppress the colony forming unit in culture. Though suppressor cells were predominantly thymus-derived (T) cells, monocytes were also effective in suppression. The suppressor efficiency of cells from the various compartments were spleen greater than bone marrow greater than peripheral blood. Splenectomy in FS transiently corrected the neutropenia and eliminated suppressor cell activity. Hyperactive suppressor cells may be responsible for the neutropenia in some patients with FS. Correction of neutropenia in these patients should be directed at modulating the suppressor cell subpopulation.
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PMID:Suppressor cell-mediated neutropenia in Felty's syndrome. 30 25

A man with polymyalgia rheumatica (patient 1) and two patients (2 and 3) with Felty's syndrome had neutropenia at the time of diagnosis. Bone marrow samples in each patient were cellular but showed an "arrest" of granulocyte maturation at the myelocyte stage. Agar colony growth of marrow cells from each patient was subnormal but increased after removal of sheep erythrocytes rosette-forming cells (thymus-dependent [T] cells) from marrow cell suspensions before culture. Preincubation of marrow cells with cortisol also enhanced colony growth. Maximum enhancement with cortisol occurred at 1 mM (patient 1), 1 microM (patient 2), and 10 nM (patient 3). Cortisol failed to enhance colony growth after removal of T cells from marrow cell suspensions. Peripheral blood lymphocytes (PBL) and PBL-conditioned medium from all three patients inhibited colony growth of normal human marrow cells. Cortisol treatment of PBL or T depletion from PBL abrogated the inhibition in coculture and with conditioned medium. Prednisone therapy resulted in the disappearance of suppressor T-cell function concomitant with hematologic improvement in patients 2 and 3, but suppressor T cells persisted in patient 1, who did not respond to prednisone. We conclude that cortisol-sensitive T lymphocytes inhibited granulopoiesis in vitro probably by elaboration of a soluble factor or factors. Our results suggest (a) that neutropenia in these patients resulted, at least in part, from T-cell suppression of granulopoiesis, (b) that the effectiveness of prednisone therapy was a result of its inhibition of suppressor T cells, and (c) that responses to glucocorticoid therapy may be predicted in such patients with the agar culture technique and cortisol dose response in vitro.
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PMID:Neutropenia in three patients with rheumatic disorders. Suppression of granulopoiesis by control-sensitive thymus-dependent lymphocytes. 31 12

The clinical and laboratory features of 72 patients with Felty's syndrome described within the last ten years have been compared with Felty's five original patients. Felty's syndrome appears to be a variant of rheumatoid arthritis with extra-articular manifestations in which leukopenia (usually due to neutropenia) and splenomegaly occur, although not always at the same time. Both are manifestations of the underlying disease process and are not necessarily otherwise related. The mechanism of the leukopenia is complex and abnormalities in leukocyte function appear to be as important as the leukopenia in predisposing patients with Felty's syndrome to infection. Functional abnormalities of the leukocytes in this syndrome are due in part to immune complex formation. Hypocomplementemia associated with this process may be another cause for the increased susceptibility to infection. It is proposed, therefore, that therapy in Felty's syndrome be directed at the underlying disease process, and gold salts and penicillamine should be considered for this purpose. Splenectomy should be reserved for specific situations, such as hemolytic anemia, severe thrombocytopenia, leg ulcers, and infections associated with profound leukopenia that are not responsive to medical therapy.
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PMID:Felty's syndrome: an analytical review. 33 Sep 14

Evidence has been found to document the presence of circulating immune complexes in all patients with Felty's syndrome. The sera of all 12 patients studied showed intermediate complexes by analytical ultracentrifugation. The sera of 9 of 12 patients (75%) showed precipitin lines upon immunodiffusion against IgM rheumatoid factor. Both findings were statistically increased above those in a matched group of patients with classic rheumatoid arthritis. The presence of circulating immune complexes in the sera of the Felty patients was consistent with the observation that large inclusions containing IgG, IgM, and complement were phagocytized by normal polymorphonuclear cells when incubated with sera of Felty patients. Normal polymorphonuclear cells phagocytosed inclusions from 77% of Felty sera, compared with 27% classic rheumatoid arthritis sera. It is suggested that the uptake of immune complexes by polymorphonuclear cells plays a role in the neutropenia of Felty's syndrome.
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PMID:Comparison of the presence of immune complexes in Felty's syndrome and rheumatoid arthritis. 41 29

Sera from patients with Felty's syndrome (FS) and rheumatoid arthritis (RA) were examined for the presence of circulating immune complexes (IC) by using the 125I-C1q binding and monoclonal rheumatoid factor (mRF) techniques. Of 15 patients with FS, 9 (60%) had high 125I-C1q binding as compared to 3 of 26 RA patients (12%). The average C1q binding was significantly higher in the FS patients than in the RA patients without FS. C1q binding in both FS and RA patients was significantly higher than a group of 90 normal controls. In addition, serum C4 levels were significantly lower in the FS patients than in the RA patients. In contrast to these findings, IC levels in FS and RA patients were very similar when measured by the mRF technique. These studies indicate that FS patients have higher levels of complement-fixing IC in their sera than RA patients without FS. These findings raise the possibility that the complement-fixing IC found in these patients may play a role in the pathogenesis of neutropenia of FS.
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PMID:Increased C1q binding immune complexes in Felty's syndrome: comparison with uncomplicated rheumatoid arthritis. 45 98

Neutrophil marrow cellularity was determined in 14 neutropenic patients with rheumatoid arthritis (RA) from measurements of neutrophil-normoblast ratios in marrow biopsies and ferrokinetic estimates of marrow normoblasts. A marrow profile was developed for each patient comprising the numbers of promyelocytes and myelocytes, of metamyelocytes and bands, and of segmented neutrophils in whole marrow. In each case a maturation ratio was calculated by dividing the number of metamyelocytes and bands by the number of promyelocytes and myelocytes. The physiologic marrow response to loss of neutrophils from circulation was assumed to be an increase in promyelocytes and myelocytes due to proliferation and influx, a reduction in segmented cells due to early release, and a normal maturation ratio. The results were interpreted in the light of the 95% confidence limits for data previously obtained from 13 normal subjects: in patients with neutropenia reduced or basal numbers of promyelocytes and myelocytes were interpreted as absence of the anticipated proliferative response; increased numbers of marrow segmented cells were attributed to failure of release; a low maturation ratio was assessed to reflect intramedullary cell loss. The pattern in two patients with Felty's syndrome was consistent with a physiological response to neutrophil destruction. The other 12 patients had neutrophil marrow abnormalities. Seven patients with Felty's syndrome and four patients without splenomegaly had absolute or relative hypoplasia of neutrophil marrow or low maturation ratios. One patient with a normal spleen size had an increased number of marrow segmented cells yet failed to mobilize cells normally in response to dialysis coil-activation of C3. Abnormalities of neutrophil marrow may contribute to neutropenia in RA irrespective of the presence of splenomegaly. Recognition of neutrophil marrow abnormalities in these patients may be of value in prognosis and management.
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PMID:Neutrophil marrow profiles in patients with rheumatoid arthritis and neutropenia. 52 42

To evaluate the effectiveness of splenectomy in the treatment of Felty's syndrome (association of rheumatoid arthritis, leukopenia, and splenomegaly), such experience from 1968 to 1972 at the University of Alabama Medical Center in Birmingham was analyzed. There were five patients with Felty's syndrome who underwent splenectomy. In all five patients, there was no operative morbidity, no blood transfusions were required, and leukopenia and susceptibility to infection were greatly improved; neutropenia disappeared in all but one patient. Splenectomy appears to benefit most patients with Felty's syndrome.
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PMID:Role of splenectomy in Felty's syndrome. 108 Mar 62

Bone marrow culture in semi-solid agar was used to assess the proliferative activity and the response to sodium aurothiomalate of the myeloid precursor cells from patients during and after recovery from neutropenia associated with the use of this drug. Colony formation was reduced during the neutropenia and returned to normal after recovery. The rheumatoid process itself did not impair colony formation even in patients with Felty's syndrome. Sodium aurothiomalate inhibited colony formation by normal marrow in a dose-dependent manner. Bone marrow colonies from patients who had recovered from neutropenia induced by sodium aurothiomalate were not abnormally sensitive to the inhibitory effect of the drug in vitro. The metabolism of gold is probably altered in a small proportion of patients, which causes high local concentrations within the bone marrow leading directly to marrow depression.
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PMID:Depression of bone marrow colony formation in gold-induced neutropenia. 111 61

We report a case of Felty's syndrome in which infectious complications due to severe neutropenia could be overcome by short-term treatment with recombinant human granulocyte-macrophage colony-stimulating factor (GM-CSF, 7 micrograms/kg/day s.c.). Leukocyte counts rose from 1,050/mm3 at presentation to 4,470/mm3 after 15 days of treatment. A flare-up of arthritis was not noted. Defects in granulocyte function and clinical improvement prior to leukocyte rise suggest that the beneficial effect of GM-CSF is mainly due to an improvement of granulocyte function.
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PMID:Felty's syndrome: favorable response to granulocyte-macrophage colony-stimulating factor in the acute phase. 151 33


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