Chronic natural killer cell lymphocytosis

Abstract

Chronic proliferations of natural killer (NK) cells (CD3- CD16+) are identified initially by detecting large granular lymphocyte (LGL) excess in a peripheral blood smear and subsequent lymphocyte immunophenotyping by flow cytometry. A related disease, T-LGL leukemia, has an indolent clinical course with chronic neutropenia and a close association with rheumatoid arthritis. Herein are described the clinical presentation and long-term clinical course of patients with chronic NK cell lymphocytosis (CNKL). The majority of the 14 patients followed up for a median of 4 years presented with severe cytopenias or vasculitic syndromes that were responsive to immunosuppressive therapy. Other manifestations included fever and arthralgias. In general, the disease was nonprogressive and had a course similar to that of T-LGL leukemia.

T-Cell Large Granular Lymphocyte Leukemia and Related Disorders

“…Males and females are affected equally. Approximately half the patients are diagnosed because of recurrent bacterial infections secondary to neutropenia, which typically include cellulitis, perirectal abscesses, or respiratory infections [8][9][10][11][12][13][14][15][16].…”

Clinicobiological, Immunophenotypic, and Molecular Characteristics of Monoclonal CD56−/+dim Chronic Natural Killer Cell Large Granular Lymphocytosis

“…Previous studies have suggested a possible association of CNKCL with cytopenias, vasculitis, neutropenic or nonneutropenic fever, BM granulomas, [1][2][3]19,20 and even Epstein-Barr virus (EBV) infection in endemic areas. 21,22 In the present study we report on the clinical, hematological, immunophenotypical, functional, serological, and molecular features of 26 patients with CNKCL in whom the expanded PB NK cells were either CD56 Ϫ or expressed very low levels of surface CD56 (CD56 Ϫ/ϩdim CNKCL) in the context of an aberrant immunophenotype and a mature LGL morphological appearance.…”

“…In summary, we describe a unique and homogeneous group of monoclonal chronic large granular NK cell lymphocytosis with an aberrant activation-related CD56 ؊ Indolent natural killer (NK) cell lymphoproliferative disorders (LPDs) are usually designated as chronic NK cell lymphocytosis (CNKCL) or chronic NK-large granular lymphocytes (LGL) LPD. [1][2][3][4][5][6] CNKCLs are heterogeneous and they most probably include reactive chronic NK cell lymphocytosis, true chronic NK cell large granular lymphocyte (LGL) leukemia, and even some aggressive NK cell lymphoma/leukemia cases, [7][8][9] because of difficulties in establishing the clonal nature of the NK cell proliferation.…”

A Canine Granular Lymphocyte Proliferative Disease Without an Aggressive Clinical Course

“…3 The disease follows an indolent clinical course characterized by lymphocytosis with bone marrow infiltration and neutropenia with recurrent infections. [1][2][3][4][5]7 Some patients have mild or moderate hepatosplenomegaly. If proof of clonality cannot be established, and in the absence of clinical evidence of malignancy, a diagnosis of GLPD often is preferred to that of leukemia.…”

“…Also referred to as large granular lymphocyte leukemia, GLPD is a clinical entity, which, in humans, is included in the classification of lymphomas. [1][2][3][4] Physiologically, LGLs represent less than 10% of normal peripheral blood lymphocytes, and constitute a morphologically distinct population characterized by abundant basophilic cytoplasm containing prominent azurophilic granules that vary in size and number. These cells are responsible for most of the natural killer (NK) cell activity and antibody-dependent cytotoxicity of peripheral mononuclear blood cells.…”