Pleural cavity separates spleen and diaphragm from the rib. The spleen is an intraperitoneal organ that lies in what quadrant and plane of the abdominal cavity. Normal histology of the human spleen van krieken j. Jan 27, 2015 spleen necrosis in a male f344n rat from a chronic study higher magnification of figure 5.
For high end tech tips, visit for latest movie trail. It has long been an organ of interest in popular as well as medical literature. The spleen is the largest mass of lymphatic tissue in the body, and is found between stomach and diaphragm. Spleen questions and study guide quizlet flashcards by kendrajs. The relationship between the spleen colonyforming cell. Blood from the red pulp collects in the venous sinuses which enter the trabeculae and merge into the trabecular veins figure 9. Spleen birte steiniger, university of marburg, marburg, germany the spleen is a secondary lymphoid organ present in all vertebrates. This lecture will provide an overview of the lymphoid structure and histology of key cells, vessels, structures and organs lymphoid organs, including the lymph nodes, spleen and thymus, as well as extranodal lymphoid tissues including mucosal associated lymphoid tissues malt. Creating videos for youtube is something called passionate task for us. The timing at which the spleen first appears varies from species to species, however in humans it is present from the fifth week of gestation or embryo development.
The spleen is the largest organ of your lymphatic system, a subdivision of the immune system. The red pulp is markedly expanded by numerous hematopoietic cells arrow. The spleen combines the innate and adaptive immune system in a uniquely organized way. The reticuloendothelial system is an expansive network that encompasses the haematopoietic centres, the formed elements they produce, as well as the conduits that transports them. The gross appearance and size of the spleen are variable, depending on the species and the degree of distension. So it is not supposed to be a link but a reference for what is coming next withing this article.
A single spleen was studied which was enlarged and all the impressions were large and deeply concave. It may be confused for enlarged lymph nodes during diagnosis. It is similar to a lymph node in shape and structure but it is much larger. One of the key structures of this system is the spleen. The risk for any infection was highest among patients who underwent splenectomy for hematopoietic cancer, but splenectomy patients with benign blood conditions also showed significantly elevated risk for infection compared with the general population, even beyond 1 year after surgery. Organization of the splenic b cell follicle in spleen r. Increased proportion of b cells in the spleen, mln, but. Guided needle core biopsy is used increasingly to sample solid lesions within the spleen and, for a variety of pathologies, laparoscopic splenectomy is now the surgical method of choice. Increased proportion of b cells in the spleen, mln, but not in the bone marrow of bafftg mice. Secondary iron overload occurs when iron accumulates in the body because people take too many iron supplements, receive a large number of blood transfusions, or have a disorder in which they cannot form red blood cells efficiently. The spleen can be a site of sequestration for any type of blood element hypersplenism results in early and excessive trapping of blood cell elements. In general, the marginal zones are much smaller and more variable than those of the rat and the white pulp is more prominent.
An acessory spleen or splenule is a small nodule formed apart from spleen. It is structurally complex and has a number of different functions such as immunological monitoring of bloodborne antigens, storage of blood and destruction of aged or abnormal blood cells. The ratio of splenic weight to body weight remains fairly constant regardless of age and, in rats, is typically around 0. These include the white pulp with tcell areas and bfollicles, the nonfiltering lymphoid areas of the red pulp, the border between red and white pulp the perifollicular zone, the red pulp cord. Despite its functional importance, the anatomy of the organ has not been studied as extensively as that of other organs, probably because its study presents intrinsic difficulties. The red pulp can be expanded markedly by venous congestion, extramedullary hematopoiesis, or by involvement by leukemias. However, most of the inflowing blood passes through the marginal sinus ms and marginal zone mz, which lie between the white. The spleen is the largest secondary lymphoid organ, is considered the draining site for compounds that are administered intravenously, and is therefore considered an important organ to evaluate for treatmentrelated lesions. The structure of the spleen enables it to remove older erythrocytes from the circulation and leads to the. The red pulp is the area of spleen in between white pulp and consists of open sinuses and cellular cords.
Detailed anatomical and embryological descriptions have been purposely omitted from this chapter, which concentrates on the surgical relevance of spleen related structures and their development. Aug 17, 2017 creating videos for youtube is something called passionate task for us. Hilum of spleen was not well made out, but on close examination, it was curvilinear. The spleen is located in the upper left abdominal cavity, just beneath the diaphragm, and posterior to the stomach. Attached to the embryo is a tissue mass known as the yolk sac which contains the cells destined to form both the spleen and stem cells that then go on to form different blood cells. Therefore, thrombocytopenia caused only by splenic sequestration. History of splenectomy for millennia, the spleen has been considered a fascinating and mysterious organ with more functions than any other organ. Figure 1 spleen, red pulp extramedullary hematopoiesis, increased in a treated male b6c3f1n mouse from a chronic study.
Volume calculated by normal ellipsoid equation correction factor 0. Megakaryocyte proliferation and atypia, often with reticulin or. The structure of the spleen enables it to remove older. Like the thymus, it only has efferent lymph vessels, which leave from. University of groningen the human spleen after trauma. This diagrammatic representation of the spleen, should help you understand where red and white pulp come from.
In inverted abdominal or systemic situs, liver is positioned on left side and spleen in right upper quadrant, often associated with spleen anomalies and variations. Structure of spleen with diagram lymphatic tissue biology. Normal structure, function, and histology of the spleen. Mouse spleen typical numberspleen mouse lymph nodes red blood cells 5 x 1012 na 2. Histology photo album home album list last uploads last comments most viewed top rated my favorites search. It is structurally complex and has a number of different functions such as immunological monitoring of bloodborne antigens, storage of. These functions are carried out by the 2 main compartments of the spleen. The necrotic focus consists of necrotic cellular debris, degenerate neutrophils, and hemorrhage arrowhead and is bordered by a rim of histiocytes, lymphocytes, and fibroblasts arrow. Despite its functional importance, the anatomy of the organ has. The main focus of this article is the histological arrangement of the spleen. For many years after its existence became known, it appeared to have no function. Like the lymph node, the human spleen is a highly compartimentalized organ. As far as the spleen of fishes is concerned, the most complete and syste matic histological description is that of. Histological disorganization of spleen compartments and severe.
In this article we will discuss about the structure of spleen with the help of suitable diagram. Sometimes, after a therapeutic splenectomy, it may show continued symptoms. Its network of trabeculae, blood vessels and lymphoid tissue provides an environment in which white blood cells lymphocytes proliferate while old damaged red blood cells erythrocytes are recycled. Nicheinduced extramedullary hematopoiesis in the spleen is. It shows how the artery has a lymphoid sheath surrounding the artery, as it enters the spleen, with aggregations of secondary lymphoid tissue.
The splenic cords contain macrophages, plasma cells, lymphocytes and other mature blood cells e. Spleen lien is the largest lymphoid tissue in the body and specialised, beenshaped organ for filtering blood. Overview of the spleen blood disorders merck manuals. Although functional asplenia is a rare event in systemic lupus erythematosus, it appears to predispose to severe septic complications. Current diagnostic pathology 1997 4, 100105 1997 pearson professional ltd histology of the spleen. The platelet count usually is 30,000mcl unless the disorder causing splenomegaly also impairs platelet production eg, in myelofibrosis with myeloid metaplasia. Normal structure, function, and histology of the spleen mark f. Spleen scan abnormalities fully reversed at 1 year. The anatomy and embryology of the spleen are well described in standard texts on those subjects 1.
B cells are found in thefollicles, marginal zone, and splenic cords. Pdf the spleen is the largest secondary immune organ in the body and is responsible for. Click here for the professional version click here for the professional version the spleen, a spongy, soft organ about as big as a persons fist, is located in the upper left part of the abdomen, just under the rib cage. Detailed anatomical and embryological descriptions have been purposely omitted from this chapter, which concentrates on the surgical relevance of spleenrelated structures and their development. Completely intraperitoneal, except at the hilum, where splenic vessels enter exit, part of foregut anatomy of spleen. Sh lecture lymphatic structure and organs embryology. Spleen necrosis in a male f344n rat from a chronic study higher magnification of figure 5. The spleen has been considered a mysterious organ since classical times. Enhanced histopathology of the spleen pubmed central pmc. Like the lymph nodes, it also has a hilus hilium which is where the major blood vessels enter and leave. In around 20% of people, incidental findings reveal a solitary or multiple accessory spleens. Mar 31, 2020 the spleen is the largest organ of your lymphatic system, a subdivision of the immune system. Blood cells spleen monocytemacrophage system thymus accessory lymphoid tissues malt, tonsils some portions of the hematopoietic system are easily accessible to clinicians and provide valuable information about the health status of the patient eg blood smears and peripheral lymph node aspirates. Relative to the rat see figure 2, the mouse spleen typically has a slightly blue tint due to the increased amounts of extramedullary hematopoiesis in the red pulp.
The trabecular veins then converge at the hilus to form the splenic vein which drains into. Spleen is an important internal organ that is on average not larger than the size of a fist. The spleen is delivered to the midline by means of blunt and sharp dissection of the areolar plane between the kidney and the pancreas. Organization of the splenic b cell follicle in spleen r openi. These changes combine an increase in the size and altered distribution of cell components. A facs staining for mature b cells using both antiigmfitc and antib220pe, in spleen top, bone marrow middle, and mln bottom. Pdf normal structure, function, and histology of the spleen. Spleen cross section for histological understanding of. Spleen pathology introduction open surgery for splenectomy is performed with diminishing frequency and pathology of this organ remains a poorly understood topic. Nicheinduced extramedullary hematopoiesis in the spleen. Splenic tissue definition of splenic tissue by medical. Anatomical and histomorphological study of spleen and. The spleen is the largest lymphatic organ in the body. Each compartment has its own structure, cell population, and functions.
If there is an excessive amount of trapping, splenectomy is sometimes recommended or the administration of na 32 po 4. Spleen cross section for histological understanding of structures. The spleen is a pulpy organ approximately the size of a fist, and contains the largest single aggregate of lymphoid tissue in the body. Spleen belongs to the lymphatic system, also note that the spleen is like a giant lymph node in the left upper quadrant of the abdomen below the left lung and diaphragm that inspects and processes the blood by filtering it past dense aggregates of lymphocytes the way that the lymph nodes treat the lymph. Need 3 major and 2 minor criteria for diagnosis of primary myelofibrosis pmf major criteria. Figure 2 spleen, red pulp extramedullary hematopoiesis, increased in a. Sequestered platelets are released from the spleen at times of stress.
Now we know this to be far from the truth, yet many individuals survive perfectly well in the absence of a functioning spleen, following surgery or as a result of diseases causing hyposplenism. The superior border shows 4 notches 3 were deep and one was shallow. Lies just beneath the left half of the diaphragm close to 9,10 and 11 ribs and on the left side of abdomen. Frozen sections of spleens from different chimeras were stained with anticd19 g. The spleen is a site of red cell elimination and destruction. There were no notches on the inferior border and intermediate border. The red pulp makes up the majority of the spleen and is composed of a network of cell cords in series with vascular sinuses. The spleen is the largest secondary immune organ in the body and is responsible for initiating immune reactions to bloodborne antigens and for filtering the blood of foreign material and old or damaged red blood cells. Jun 12, 2011 spleen is an important internal organ that is on average not larger than the size of a fist. Anatomical and histomorphological study of spleen and pancreas in berzem barbus pectoralis 1mahmood khaksary mahabady, 2hassan morovvati, 2ameneh arefi and 3masoud karamifar 1department of anatomy and embryology, school of veterinary medicine, shahid chamran university of ahvaz, ahvaz, iran. Surrounded by a connective tissue capsule, which extends inward to divide the organ into lobules, the spleen consists of two types of tissue. It is a highly vascular haemopoietic organ situated in the left hypochondrium directly beneath the. Usually, it is found near the hilum of the main spleen, but also further in the abdomen, or even in the pelvic or scrotal area.
Spleen questions and study guide quizlet flashcards by. Increased proportion of b cells in the spleen, mln, but openi. Emerging role of the spleen in the pharmacokinetics of. Hi algarcy, here refers to this article below the abstract. With the spleen retracted medially, the phrenicocolic ligament is incised. Recovery of cfus, both quantitatively and qualitatively, can proceed differently depending upon the cytotoxic agent or. Histological disorganization of spleen compartments and severe visceral. Thrombocytopenia due to splenic sequestration hematology. Although it may seem dispensable as it is possible to live without it, the spleen is constantly.
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