Neutrophil kinetics in Felty's syndrome

Low Fcgamma receptor III and high granulocyte colony-stimulating factor serum levels correlate with the risk of infection in neutropenia due to Felty's syndrome or systemic lupus erythematosus

PURPOSE

To determine whether serum levels of soluble Fcgamma receptor III and granulocyte colony-stimulating factor (G-CSF) are associated with the risk of infection in patients with neutropenia due to Felty's syndrome or systemic lupus erythematosus.

SUBJECTS AND METHODS

Serum levels of G-CSF and soluble Fcgamma receptor III were measured by enzyme-linked immunosorbent assays in 13 patients with neutropenia due to Felty's syndrome, 10 patients with neutropenia due to systemic lupus erythematosus, and 41 controls with normal leukocyte counts (25 with systemic lupus erythematosus, 16 with rheumatoid arthritis). We calculated the area under the receiver operating characteristic (ROC) curves for the absolute neutrophil count, soluble Fcgamma receptor III levels, and G-CSF levels.

RESULTS

Nine of the neutropenic patients (7 with Felty's syndrome, 2 with lupus) had one or more infections within 3 months before and after blood samples were obtained. Absolute neutrophil counts were similar in neutropenic patients who did or did not have infections. However, the median level of soluble Fcgamma receptor III (63 vs. 126 arbitrary units, P = 0.005) was significantly lower among patients who developed infections, whereas the median level of G-CSF (90.9 vs. 53.3 pg/mL, P = 0.04) was significantly higher compared with patients without infections. The area under the ROC curve was 0.58 (P = 0.49) for the absolute neutrophil count, 0.84 (P = 0.007) for soluble Fcgamma receptor III levels, and 0.73 (P = 0.03) for G-CSF levels.

CONCLUSION

In patients with chronic neutropenia due to rheumatic diseases, low soluble Fcgamma receptor III levels and elevated G-CSF levels are better indicators of the risk of infection than is the neutrophil count.

Non-malignant neutropenia

Neutropenia occurs when the production of neutrophils by the bone marrow is outpaced by utilization in the periphery. Abnormalities of hematopoietic stem-cell development and decreased proliferation of neutrophil precursors in the marrow can reduce production of neutrophils. Conversely, decreased neutrophil survival in the peripheral circulation can also give rise to neutropenia. Non-malignant neutropenia of acute onset can be caused by infection, antibody-mediated destruction, or an idiosyncratic reaction to a drug. Severe chronic neutropenia is a global, descriptive term for several disorders of varied etiologies in which neutrophil levels are consistently or recurrently at levels less than 0.5 x 10(9)/L. Despite this heterogeneity of origin, administration of recombinant human granulocyte colony stimulating factor to individuals with severe chronic neutropenia results in an increase in neutrophil counts in most patients associated with a significantly improved quality of life.

Autoimmune neutropenia manifesting as recurrent oral ulceration

There are many causes of recurrent oral mucosal ulceration, particularly gastrointestinal, mucocutaneous, and hematologic disease. The present report details the features of a patient with recurrent oral ulceration caused by autoimmune neutropenia.

Felty's and pseudo-Felty's syndromes

Felty's syndrome, consisting of rheumatoid arthritis, leukopenia, and splenomegaly, has been recognized as a distinct clinical entity for more than 60 years. Clinical and laboratory manifestations of the condition are reviewed. The major sources of morbidity and mortality remain recurrent local and systemic infections. Immunogenetic analysis shows a strong association with HLA-DR4, in addition to DQ beta 3b and C4B null allele. Potential mechanisms of neutropenia are contrasted, including impaired granulopoiesis and neutrophil-immune complex interactions. Lithium carbonate and splenectomy may have a role in the treatment of fulminant disease. Maintenance therapy should be directed at control of the underlying inflammatory arthropathy. A syndrome of proliferation of large granular lymphocytes and neutropenia, associated with rheumatoid arthritis in 23% to 39% of cases, has been described recently. Cases of "pseudo-Felty's" syndrome are often confused with traditional Felty's syndrome, which has twice the prevalence. The clinical and laboratory distinctions between these two conditions are elaborated.

Double-blind, placebo-controlled lithium treatment in chemotherapy induced aplasia for AML: reduced antibiotic requirement

A double-blind placebo-controlled study on lithium (Li) therapy after chemotherapy-induced bone marrow aplasia was undertaken in 53 patients with acute myeloblastic leukemia (AML). No difference was observed between the two groups for the duration of aplasia, the number of units of platelets or RBC transfused, the complete remission rate or the disease free survival. However, a statistically significant reduction in the number of days of antibiotic therapy required was found in the treated group (10.55 +/- 2.72 vs 12.73 +/- 3.60, P less than 0.05).

Identification by cell electrophoresis of a subpopulation of polymorphonuclear cells which is increased in patients with rheumatoid arthritis and certain other rheumatological disorders

Two and occasionally three electrophoretic subpopulations of polymorphonuclear cells (PMNs) were identified in the blood of normal healthy subjects and patients with rheumatoid arthritis (RA). Most of the PMNs from both groups of subjects were found in the population with the highest surface charge; the remainder being in the other distributions, which were collectively termed the slow cell population. There was a significant increase in the percentage of rheumatoid PMNs (mean 42%) ascribed to the slow population when compared with PMNs from normal subjects (mean 17%). A similar increase in the slow cell population was also seen in patients with Felty's syndrome (mean 38%) and scleroderma (mean 51%), but not in patients with Behçet's syndrome (mean 18%). Synovial fluid aspirated from the knee joints of patients with RA contained PMNs with the lowest surface charge. With nylon fibre as an adherence substrate cells of a low surface charge were found to be more adherent than those of a high surface charge. An alteration in the electrophoretic distribution of PMNs may represent changes that are related to the expression of functionally related membrane ionogenic groups.

The spleen in Felty's syndrome: a histological, morphometrical, and immunohistochemical study

A histological study employing morphometrical and immunohistochemical methods was performed in 3 spleens removed because of Felty's syndrome (FS). A comparison was made with control spleens and with spleens removed from patients with idiopathic thrombocytopenic purpura (ITP) or autoimmune hemolytic anemia (AIHA). In FS, the spleen is enlarged, mainly due to expansion of the red pulp. The sinuses are enlarged, too, and contain many macrophages. 2 of our specimens showed many hyperplastic germinal centers; the 3rd contained no germinal centers. Only in the former cases did splenectomy lead to an increase in the number of circulating granulocytes. Immunohistologically, FS spleens differed from the control, the ITP, and the AIHA spleens. The results have provided further evidence indicating that the pathogenesis of granulocytopenia in FS differs from that of autoimmune hematocytopenias, and have given rise to the hypothesis that, in FS, the spleen is the site of interaction between immune complexes and granulocytes.

Felty's syndrome: long-term followup after treatment with auranofin

Five patients who had Felty's syndrome were treated with auranofin, 6 mg/day, for a period that ranged from 4 months to 2 years. All patients experienced both an improvement in articular symptoms and a normalization of the leukocyte count. Auranofin appears to be an effective treatment for Felty's syndrome, and to have a lower degree of toxicity than parenteral gold.

Immune complexes and the pathogenesis of neutropenia in Felty's syndrome

The effect of the injection of serum from patients with rheumatoid arthritis (RA) and Felty's syndrome (FS) into mice on the number of circulating polymorphonuclear cells (PMN) was studied. The number of circulating PMN dropped to 61% (range 34-98%) of the initial counts after the injection of FS serum. This phenomenon was observed less frequently after injection of RA serum. In contrast, injection of serum from healthy controls always resulted in an immediate increase in the number of circulating PMN. No decrease in PMN counts was found after injection of FS sera pretreated with polyethylene glycol to precipitate immune complexes (IC). Gel filtration of FS sera on Sepharose 4B showed that the effect on the PMN counts in mice did not coincide with the 7S peak but occurred only in fractions containing larger material. Serum fractions from FS patients that contained IC were more active in producing neutropenia than the corresponding fractions from patients with RA. Microscopic and immunohistochemical examination of the organs from mice injected with FS serum showed sequestration of PMN and deposition of human IgG, IgA, and IgM in the vascular bed of the lungs. These results indicate that the interaction between PMN and IC of patients with FS leads to sequestration of PMN in mice and suggests that this interaction in humans may have a role in the pathogenesis of FS.

Radiolabeled blood cells: techniques and applications

During the past few years, the clinical and experimental applications of autologous blood cells labeled with gamma-emitting radionuclides, i.e., technetium-99m (Tc-99m) and indium-111 (In-111) have continued to grow rapidly. Investigations have centered around developing techniques that would label blood cells efficiently without alteration of cell viability and their pathophysiologic integrity. Experimental and clinical applications have been aimed at the studies of in vivo cell kinetics and detecting abnormal lesions by external imaging. These will be discussed in detail together with their advantages and disadvantages, and the future directions will be outlined.

Felty syndrome: autoimmune neutropenia or immune-complex-mediated disease?

Immunofluorescence on polymorphonuclear cells (PMN) of patients with Felty syndrome (FS) revealed increased amounts of IgG, IgA, and IgM bound to the PMN surface compared with PMN of patients with rheumatoid arthritis alone. A positive correlation was found between the score for surface-bound immunoglobulins on FS-PMN and the results of the Clq binding assay in FS sera. After preincubation with sera from 20 patients with FS, immunofluorescence on PMN from healthy controls (HC) showed that these cells had bound IgG, IgA, and IgM. However F(ab')2 fragments of IgG from FS sera did not bind to PMN, although the antigen-binding reactivity of the F(ab')2 fragments was maintained as shown by control experiments. Immunoglobulins eluted from FS-PMN failed to bind to HC-PMN, whereas the corresponding IgG of patients with autoimmune neutropenia was bound. Gel filtration of FS sera on Sepharose 4B showed that the binding of IgG in FS sera to PMN did not coincide with the 7S peak but occurred mainly in fractions containing larger material. No binding of IgA and IgM to HC-PMN was found after incubation with FS sera pretreated with polyethylene glycol (PEG) to precipitate immune complexes. These results indicate that in sera of patients with FS the PMN-binding reactivity of IgG, IgA, and IgM is due to the binding of immune complexes containing these immunoglobulins and not to presence of autoantibodies directed to antigens on the neutrophil surface.

Splenectomy for hematologic disease. The UCLA experience with 306 patients

Between 1956 and 1981, 306 splenectomies for hematologic diseases were performed at the UCLA Medical Center. Of these operations, more than 75% were performed for therapeutic reasons to control anemia, thrombocytopenia, neutropenia, or painful symptoms of splenomegaly. Of the 65 patients who had idiopathic thrombocytopenic purpura, 77% showed an excellent response, and of the 39 patients who had hereditary spherocytosis, 90% responded. Other diseases with predictably good response rates were autoimmune hemolytic anemias, Felty's syndrome, and hairy cell leukemia. Forty patients with Hodgkin's disease had splenectomies for diagnostic purposes the last 10 years. The overall morbidity and mortality were 24% and 6%, respectively, the most common complications being pneumonia, wound infections, and local postoperative bleeding, and the most common cause of death being sepsis. The review supports the thesis that in carefully selected patients, therapeutic splenectomy can have desirable palliative effects and that diagnostic splenectomy has a sufficiently low risk to warrant its consideration in patients with Hodgkin's disease.

Labeled cells in the investigation of hematologic disorders

Radiolabeling techniques for white cells, platelets, and erythrocytes are reviewed. The early studies using diisopropylfluoro-32P contributed to an understanding of the production and circulation of the blood elements, and 51Cr proved useful in localizing sites of cell migration or destruction. 111In-oxine has further improved the understanding of blood cell organ sequestration, and permitted combined kinetic and organ imaging studies. Radionuclide labels have been essential for the elucidation of various hematologic disorders, such as the neutropenias, thrombocytopenias, anemias, and polycythemia. Many new treatments, including monoclonal antibodies, have been evaluated with radionuclides.

Heterogeneity of bone marrow-directed immune mechanisms in the pathogenesis of neutropenia of Felty's syndrome

Twenty-seven patients with Felty's syndrome were studied by the colony forming unit in culture (CFU-C) assay for possible immune mechanisms within the bone marrow compartment that could contribute to the neutropenia. Depletion of bone marrow suppressor T cells resulted in normal CFU-C numbers in 7 patients. In 5 patients serum antiprecursor cell activity was detected. Blood monocytes failed to generate colony stimulating factor in 5 patients. Bone marrow-directed immune mechanisms are heterogeneous and could play a role in the pathogenesis of neutropenia in some patients with Felty's syndrome.

Granulocyte demargination by epinephrine in evaluation of hypersplenic states

The usefulness of the epinephrine stimulation test in detecting granulocytic hypersplenism is evaluated. In 8 hypersplenic patients, an increment of the granulocyte count of 170% over baseline values was found, compared to 38% (P less than 0.001) in normal subjects and 44% )P less than 0.002) in patients neutropenic from other causes. No overlap of individual test results was found among the hypersplenic and the control groups. Epinephrine test discriminates between neutropenia from hypersplenism and neutropenia from other causes. Furthermore, this test is found to be a valuable adjunct to the hydrocortisone stimulation test in kinetic evaluation of neutropenia from any cause.