Classification & external resources
Malignant histiocytosis is a hereditary disease found in the Bernese Mountain Dog characterized by histiocytic infiltration of the lungs and lymph nodes. The liver, spleen, and central nervous system can also be affected. Histiocytes are a component of the immune system that proliferate abnormally in this disease. In addition to its importance in veterinary medicine, the condition is also important in human pathology.
A histiocyte is a differentiated tissue cell that has its origin in the bone marrow. The source for histiocytes is the monocyte/macrophage line. Monocytes (found in the blood) and macrophages (found in tissue) are responsible for phagocytosis (ingestion) of foreign material in the body. Langerhans cells are dendritic cells found in the skin and function by internalizing antigens (foreign particles) and presenting them to T cells. They arise from monocytes. Histiocytic disorders refer to diseases that are caused by abnormal behavior of these cells. They include the following:
- Reactive diseases of Langerhans cells
- Reactive diseases of macrophages
- Malignant diseases of Langerhans dells
- Malignant histiocytosis
- Diffuse histiocytic sarcoma
- Localized histiocytic sarcoma
- Malignant diseases of macrophages
Up to 25 percent of Bernese Mountain Dogs may develop malignant histiocytosis in their lifetime. Other breeds with a possible genetic tendency toward malignant histiocytosis include Rottweilers, Flat-Coated Retrievers, and Golden Retrievers.
Signs and symptoms
The disease in the lungs is characterized by enlargement of the tracheobronchial lymph nodes and infiltration of the lungs, sometimes leading to lung lobe consolidation and pleural effusion. Signs and symptoms include cough, loss of appetite, weight loss, anemia, and difficulty breathing. Seizures and rear limb weakness can be seen. Invasion of the bone marrow can cause pancytopenia. Diagnosis requires a biopsy.
Treatment with chemotherapy has been used with some success, particularly using lomustine, prednisone, doxorubicin, and cyclophosphamide. Because of the rapid progression of this aggressive disease, the prognosis is very poor.
Other histiocytic diseases in Bernese Mountain Dogs
A similar disease is diffuse histiocytic sarcoma, a term used to designate a localized histiocytic sarcoma that has spread throughout the body.
Another disease of histiocytic origin that affects Bernese Mountain Dogs is systemic histiocytosis. This condition generally begins as lesions on the eyelids, nasal mucosa, and skin, especially the scrotum. It progresses to a more generalized disease affecting the lymph nodes, bone marrow and spleen. Other signs and symptoms include weight loss and loss of appetite. It also has a very poor prognosis.
- ^ http://dermnetnz.org/dermal-infiltrative/malignant-histiocytoses.html
- ^ Ginhoux F, Tacke F, Angeli V, Bogunovic M, Loubeau M, Dai XM, Stanley ER, Randolph GJ, Merad M (2006). "Langerhans cells arise from monocytes in vivo". Nat. Immunol. 7 (3): 265-73. PMID 16444257.
- ^ Parker, A.G., Rutteman, G.R., Cadieu, E., et al. (2006). Malignant Histiocytosis in the Bernese Mountain Dog: Design and Execution of a Case-Control Study. Genes, Dogs and Cancer: Fourth Annual Canine Cancer Conference. Retrieved on 2007-01-28.
- ^ Ettinger, Stephen J.;Feldman, Edward C. (1995). Textbook of Veterinary Internal Medicine, 4th ed., W.B. Saunders Company. ISBN 0-7216-6795-3.
- ^ Kessler, Martin (2006). Radiographic diagnosis of primary and metastatic lung tumors. Proceedings of the North American Veterinary Conference. Retrieved on 2007-01-28.
- ^ Affolter, Verena K. (2004). Histiocytic Proliferative Diseases in Dogs and Cats. Proceedings of the 29th World Congress of the World Small Animal Veterinary Association. Retrieved on 2007-01-28.
- ^ Kearns, Shawn Ann; Ewing, Patty (Feb. 2006). "Causes of canine and feline pancytopenia". Compendium on Continuing Education for the Practicing Veterinarian 28 (2): 122-133. Veterinary Learning Systems.
- ^ a b c Cronin, Kim (Dec. 2006). "Deciphering the histiocytic code". DVM: 1S-8S. Advanstar Communications.
- ^ Affolter V, Moore P (2002). "Localized and disseminated histiocytic sarcoma of dendritic cell origin in dogs". Vet Pathol 39 (1): 74-83. PMID 12102221.
- ^ Tumors with Histiocytic Differentiation. The Merck Veterinary Manual (2006). Retrieved on 2007-01-28.
|Pathology: hematology (primarily C81-C96/200-208, D45-D47, D50-D77/280-289)|
|WBCs||hematological malignancy (lymphoma, leukemia, multiple myeloma), myeloproliferative disease, myelodysplastic syndrome|
-cytosis (Agranulocytosis, Leukocytosis, Lymphocytosis, Monocytosis) • -penia (Lymphopenia, Neutropenia)
|nutritional anemia: Iron deficiency anemia, Plummer-Vinson syndrome, Megaloblastic anemia (Pernicious anemia)|
hereditary hemolytic anemia: G6PD Deficiency, Thalassemia, Sickle-cell disease/trait, Hereditary spherocytosis, Hereditary elliptocytosis, Hereditary stomatocytosis
acquired hemolytic anemia: Autoimmune (Warm), HUS, MAHA, PNH, PCH
aplastic anemia: Acquired PRCA, Diamond-Blackfan anemia, Fanconi anemia • Sideroblastic anemia • Hemochromatosis
|Coagulation/platelets||coagulopathy: DIC • Hemophilia (A/VII, B/IX, C/XI, XIII) • Von Willebrand disease
Purpura: Henoch-Schönlein, ITP (Evans syndrome), TTP
primary hypercoagulable state: Protein C deficiency -
Protein S deficiency - Antithrombin III deficiency - Antiphospholipid syndrome - Factor V Leiden
other hemorrhagic conditions: Bernard-Soulier syndrome - Glanzmann's thrombasthenia - Grey platelet syndrome
|Histiocytosis||WHO-I Langerhans cell histiocytosis - non-Langerhans-cell histiocytosis/WHO-II (Juvenile xanthogranuloma, Hemophagocytic lymphohistiocytosis) - malignant histiocytic disorders/WHO-III (Acute monocytic leukemia, Malignant histiocytosis, Erdheim-Chester disease)|
|Other||Asplenia/hyposplenism - Methemoglobinemia|
|Hematological malignancy histology (ICD-O 9590-9989)|
|Lymphomas (9590-9759)||Hodgkin's lymphoma vs. Non-Hodgkin lymphoma - Diffuse lymphoma vs. Follicular lymphoma|
B-cell lymphoma (Small cell, Primary effusion, Diffuse large, ,Burkitt's, Splenic marginal zone, MALT)
mast cell tumor (Mast-cell sarcoma, Malignant mastocytosis, Malignant histiocytosis, Langerhans cell histiocytosis)
T-cell lymphoma (Cutaneous , Mycosis fungoides/Sézary's disease, Angioimmunoblastic, Anaplastic large cell, Hepatosplenic)
plasma cell (Plasmacytoma, Multiple myeloma)
|Immunoproliferative disorders (9760-9799)||Waldenström macroglobulinemia - Lymphomatoid granulomatosis|
|Lymphoid leukemias (9800-9839)||ALL - CLL - T-cell leukemia (Adult, Large granular lymphocyte, Prolymphocytic, Acute lymphoblastic) - B-cell leukemia (Prolymphocytic)|
|Myeloid leukemias (9840-9939, 9963)||AML (M2, APL/M3, AMoL/M5, Erythroleukemia/M6) - CML (CMoL, CNL, Philadelphia chromosome) - Granulocytic sarcoma|
|Other leukemias (9940-9949)||Hairy cell leukemia - Aggressive NK-cell leukemia|
|Myeloproliferative disease (9950-9961)||Polycythemia vera - Essential thrombocytosis - Myelofibrosis|
|Other (9964-9989)||Hypereosinophilic syndrome - Post-transplant lymphoproliferative disorder - Myelodysplastic syndrome|