Antigens, CD ; immunology ; Antigens, Differentiation, Myelomonocytic ; immunology ; Child, Preschool ; Diagnosis, Differential ; Histiocytes ; immunology ; pathology ; Histiocytosis, Sinus ; diagnosis ; pathology ; Humans ; Lymph Nodes ; immunology ; pathology ; Lymphatic Diseases ; diagnosis ; pathology ; Male

The causes of cytopenia in patients with severe fever with thrombocytopenia syndrome (SFTS) are not fully understood until now. We reviewed the bone marrow (BM) findings of patients with SFTS to unravel the cause of the cytopenia. Three Korean SFTS were enrolled in this study. Thrombocytopenia, neutropenia, and anemia were detected in all three patients. Severe hypocellular marrow (overall cellularity <5%) and a decreased number of megakaryocytes were noted in one patient, and hypo-/normocellular marrow and an increased number of hemophagocytic histiocytes were observed in two patients. Megakaryocytes were relatively preserved in two patients. Although a limited number of cases are available, our observations suggest that both BM suppression and peripheral destruction or sequestration are causes of cytopenia of patients with SFTS. To the best of our knowledge, this is the first well documented pathologic evaluation of Korean SFTS.
Aged ; Aged, 80 and over ; Bone Marrow/*pathology ; Female ; Fever/*complications ; Histiocytes/*pathology ; Humans ; Male ; Middle Aged ; Neutropenia/complications ; Pancytopenia/complications ; Syndrome ; Thrombocytopenia/*complications/*immunology

We reviewed clinical and pathologic characteristics of 18 cases of malignant histiocytosis including 2 autopsy cases with special interest on their immunohistochemical characteristics. We report 3 cases of unusual immunohistochemical finding and postulate these cases may be a supportive evidence of the view that dendritic cells share common precursor with those of mononuclear phagocytic system. More accumulated cases in the future and careful analysis would be needed to answer the basic question about the origin of malignant histiocytosis.
Adolescent ; Adult ; Antigens, Differentiation/analysis ; Biopsy ; Child ; Dendritic Cells/pathology ; Female ; Histiocytes/pathology ; Histiocytic Sarcoma/immunology/*pathology ; Humans ; Male ; Middle Aged ; Tumor Markers, Biological/analysis

The recent advances in the basic hematology and immunology have significantly enhanced the understanding of histiocytic disorders. The Histiocyte Society which was established in 1985 enabled the randomized trials for these diseases, and important knowledge regarding pathogenesis, clinical presentation, diagnosis, therapy and late consequences has been obtained. The treatment of Langerhans cell histiocytosis (LCH) has varied greatly over last decades, and is still controversial. Therapy can be reduced for low risk patients, and it is possible to discriminate early the non-responding patients with risk disease who might require more intensified treatment. Current therapy of LCH recommended by the Histiocyte Society (LCH-III protocol) is activated in 2001. Hemophaocytic histiocytosis (HLH) is fatal if diagnosis is delayed and appropriate therapy is not instituted rapidly. The diagnostic criteria for HLH is revised by the Histiocyte Society for the current treatment protocol (HLH-2004) which consists of dexamethasone, etoposide, and cyclosporin in combination with intathecal methotrexate. Hematopoietic stem cell transplantation is usually necessary for the primary HLH and recurrent secondary HLH.
Allergy and Immunology ; Clinical Protocols ; Cyclosporine ; Dexamethasone ; Diagnosis ; Etoposide ; Hematology ; Hematopoietic Stem Cell Transplantation ; Histiocytes ; Histiocytosis ; Histiocytosis, Langerhans-Cell ; Humans ; Lymphohistiocytosis, Hemophagocytic ; Methotrexate

Cutaneous nocardiosis, which usually manifests in the form of pustules, abscesses, or subcutaneous nodules, is occasionally found in immunocompromised patients. A 59-yr-old Korean man with myasthenia gravis and thymoma developed nodular skin lesions on his trunk. Histopathologically, abscess formation with a dense infiltrate of neutrophils and many cytophagic histiocytes were observed. Numerous filamentous organisms, which turned out to be Nocardia asteroides by culture, were also found. After sulfamethoxazole-trimethoprim therapy, all of the skin lesions rapidly decreased in size, with a marked diminution of the number of cytophagic histiocytes, and cleared up within four months. On reporting a case of cutaneous nocardiosis showing unusual histopathologic findings, we considered that reactive conditions should be included in the differential diagnosis of the cutaneous cytophagocytosis, and that nocardiosis could be one of the diseases showing reactive cytophagocytosis.
Anti-Bacterial Agents/therapeutic use ; Histiocytes/*immunology ; Humans ; Male ; Middle Aged ; Myasthenia Gravis/complications ; Neutrophils/*immunology ; Nocardia Infections/drug therapy/*immunology/microbiology/pathology ; Nocardia asteroides/drug effects/*immunology/isolation & purification ; Phagocytosis/*immunology ; Skin Diseases, Bacterial/drug therapy/*immunology/microbiology/pathology ; Thymoma/complications ; Thymus Neoplasms/complications ; Treatment Outcome ; Trimethoprim-Sulfamethoxazole Combination/therapeutic use

Aged ; Antigens, CD ; metabolism ; Antigens, CD20 ; metabolism ; Antigens, Differentiation, Myelomonocytic ; metabolism ; CD3 Complex ; metabolism ; CD79 Antigens ; metabolism ; Diagnosis, Differential ; Histiocytes ; immunology ; pathology ; Hodgkin Disease ; immunology ; pathology ; Humans ; Leukocyte Common Antigens ; metabolism ; Lymphoma, B-Cell ; immunology ; pathology ; Lymphoma, Large B-Cell, Diffuse ; immunology ; pathology ; Male ; T-Lymphocytes ; immunology ; pathology

OBJECTIVETo study the clinical manifestation, pathologic features and immunophenotype of histiocytic necrotizing lymphadenitis (HNL).

METHODSThe clinicopathologic data of 84 patients with HNL from 2005 to 2014 were retrospectively studied. Immunohistochemical staining using EliVision method for CD20, PAX5, CD3, CD45RO, CD4, CD8, CD56, CD68, CD123, granzyme-B, TIA1 and MPO was carried out. In-situ hybridization for Epstein-Barr virus RNA was performed on archival lymph node biopsy tissue.

RESULTSImmunohistochemical study showed that the lesional cells were predominantly histiocytes (CD68+), plasmacytoid dendritic cells (CD123+) and T lymphocytes (CD3+ and CD45RO+). Clusters of CD68-positive cells with strong and diffuse MPO expression were identified. T lymphocytes with CD4 and CD8 positivity were noted. CD56+ natural killer cells and CD20+/PAX5 B cells were rare. Apoptosis-related markers, including TIA1 and granzyme B were expressed by T lymphocytes and histiocytes in lymph nodes of HNL. In-situ hybridization for Epstein-Barr virus RNA was positive in only 10.0% of the cases.

CONCLUSIONSHNL shows no specific clinical and laboratory findings. Recognition of the characteristic histopathologic changes in lymph node biopsy of HNL is the key to correct diagnosis. Immunohistochemical study using a panel of markers, including CD3, CD4, CD8, MPO, CD123, granzyme-B and TIA1, is helpful in the differential diagnosis of HNL.

Antigens, CD ; analysis ; Biomarkers ; Dendritic Cells ; pathology ; Diagnosis, Differential ; Granzymes ; analysis ; Herpesvirus 4, Human ; genetics ; Histiocytes ; pathology ; Histiocytic Necrotizing Lymphadenitis ; complications ; immunology ; pathology ; virology ; Humans ; Immunohistochemistry ; Immunophenotyping ; In Situ Hybridization ; methods ; Lymph Nodes ; RNA, Viral ; analysis ; Retrospective Studies ; T-Lymphocytes ; immunology ; pathology