Lymphatic, Immune, Hematologic, Hematopoietic systems

Lymphatic system / 89890002 |Structure of lymphatic system (body structure)|

Set of structures through which lymph flows. It includes 59441001 | Structure of lymph node (body structure) | and 83555006 | Structure of lymphatic vessel (body structure) |. It supports the categorization of findings, disorders and procedures that relate to the flow of lymph.

Lymphoid system / 122490001 |Lymphoid system structure (body structure)|

Set of structures with groups of lymphoid cells, including those in the intestines, marrow, liver, and other locations, and the lymph nodes, spleen, thymus, and tonsils and adenoids; excludes the lymph vessels. It supports categorization of lymphomas.

Immune system / 116003000 |Structure of immune system (body structure)|

All of the lymphoid system, as well as the mononuclear phagocytic system; the immune system also includes cellular and sub-cellular components involved in cellular and humoral immunity.

Mononuclear phagocytic system / 127908000 |Mononuclear phagocyte system structure (body structure)|

Collection of true macrophages, distributed widely in the body (splenic and lymphoid sinusoids, liver Kuppfer cells, pulmonary alveolar macrophages, osteoclasts, macrophages in serous membranes, and microgliocytes); also endothelial cells that line hematopoietic tissues.

Dendritic cell system / 127909008 |Dendritic cell system structure (body structure)|

Collection of antigen-presenting cells, including the following: epidermal Langerhans, dendritic reticulum, and interdigitating. Class I histiocytoses (Langerhans cell histiocytosis) are disorders of the dendritic cell system.

Hematologic system / 414387006 |Structure of hematological system (body structure)|

Bone marrow, the lymphoid system, the hematopoietic system, and the terminal cells of all lineages of the hematopoietic system (red cells, white cells, platelets, histiocytes, plasma cells, etc.). Disorders of the hematologic system do not necessarily include disorders of the hemostatic system, even though bleeding and thrombosis are usually categorized as hematologic.

Hematopoietic system / 57171008 |Hematopoietic system structure (body structure)|

Structures and cells responsible for erythropoiesis, granulocytopoiesis, monocytopoiesis, thrombocytopoiesis, and lymphopoiesis. Refers to the immature cellular elements that eventually form the cellular components of blood. The blood itself cannot be strictly part of the hematopoietic system, since this would cause all components of blood to be part of the hematopoietic system (including components like albumin, clearly not hematopoietic). SNOMED CT considers leukocytes, erythrocytes, and platelets the result of hematopoiesis, but not blood-forming, otherwise leukocytosis would become a disorder of hematopoiesis, whereas it can arise simply from a demargination of white cells following stress. SNOMED CT has a concept named 419333002 | Cellular component of blood (substance) |; note that platelets are not actually cells, but are cellular components.

Modeling

Hematopoietic should be differentiated from hematologic , since the terminal cells of each lineage (the erythrocyte, segmented neutrophil, monocyte, histiocyte, platelet, mature T- and B-cells, plasma cells, etc.) are not strictly hematopoietic.

Blood

The blood is not necessarily part of the cardiovascular system, nor is it necessarily part of the hematopoietic system. 87612001 |Blood (substance)| is a body fluid, not strictly part of either the hematopoietic or cardiovascular systems.

Single versus multiple lymph node(s)

|Lymph node structure| could be a single node or multiple nodes. A term in single form does not mean it is a single anatomical entity. For example, | Inguinal lymph node structure | represents the lymph node(s) in the inguinal region. It is a representation of the type of anatomical entity. A 'Lymph node group' concept could have two distinctive concepts, e.g. lymph node of a particular classification group, or a group of nodes, representing the lymph node according to different groups in most cases. If it represents a group of nodes, the description should be in the plural form.

Regional lymph nodes of lungs

SNOMED CT has lymph node concepts per their anatomical locations, e.g. pulmonary, bronchopulmonary, tracheobronchial, tracheal, and esophageal) and concepts for node groups used for clinical staging of lung cancer, i.e., lymph nodes categorized into 14 stations.

Professional societies concerned with the clinical staging of lung cancer have developed at least three different nomenclatures for stations of lung-related lymph nodes. Even though the numbering of the stations is very similar, the inter-relationships between the various node groups are complex, particularly in stations 4 and 10, near the carina and hilar regions.

SNOMED International considers American Joint Committee on Cancer (AJCC) Station 10 , hilar lymph node, bronchial lymph node, and bronchopulmonary lymph node as synonyms. The American Thoracic Society (ATS) Station 10R, the right tracheobronchial lymph node is not a subtype of tracheobronchial lymph node because its definition includes nodes covered by both lower paratracheal lymph node,(AJCC Station 4) and by the hilar lymph node (AJCC Station 10). SNOMED CT uses tracheobronchial lymph node as a supertype of both inferior tracheobronchial (subcarinal) and superior tracheobronchial (a subset of lower paratracheal).

Provide Feedback