Function of lymph nodes + spleen Flashcards
Function of the lymphatic system
filter lymph + return lymph to the circulation (prevents oedema)
primary lymphoid tissues
bone marrow
thymus
secondary lymphoid tissues
lymph nodes
spleen
tonsils
what in lymph nodes ensures unidirectional lymph flow
valves
what cells are seen in lymph nodes
Lymphocytes: B cells, T cells, NK cells
Macrophage
Dendritic cells
Endothelial cells
where do B cells mature
bone marrow
where do T cells mature
Thymus
where in the lymph node is lymph filtered
node parenchyma
marker for B cell
CD20
marker for T cell
CD3
causes of lymphadenopathy
local inflammation
systemic inflammation
malignancy (haematological/metastatic)
other conditions e.g. sarcoidosis
what is lymphangitis
superficial infection may see red lines extending up lymph tract from an inflamed lesion
what would a lymphadenopathy of predominant B cells mean
autoimmune conditions
infections
what would a lymphadenopathy of predominant phagocytic response mean
draining a tumour site
what would a lymphadenopathy of predominant T cells mean
viral infections
drugs e.g. phenytoin
what is a malignant lymphadenopathy called
lymphoma
what does a generalised lymphadenopathy suggest
systemic inflammatory process or widespread malignancy
where is the spleen located
is it palpable?
left upper quadrant
not usually palpable unless substantially enlgarged
blood supply to the spleen
splenic artery
what is the splenic artery a branch of
coeliac axis
what vessel drains the spleen
splenic vein
what two vessels form the portal vein
splenic vein
superior mesenteric vein
what does the parenchyma of the spleen include
red pulp
white pulp
contents of the red pulp of the spleen
sinusoids + cords (contain macrophage + some fibroblasts)
what does the white pulp in the spleen do
comprises the peri-arteriolar lymphoid sheath (PALS)
Contains CD4+ cells and lymphoid cells
how does PALS work
antigen reaches white pulp via the blood
antigen presenting cells in the white pulp present antigen to immune reactive cells
when stimulated by antigen, T and B cell responses may occur
features of splenomegaly
dragging sensation in LUQ
discomfort with eating
pain if infarction
hypersplenism
triad of hypersplenism
splenomegaly
fall in one or more cellular components of blood
correction of cytopenias by splenectomy
infective causes of splenomegaly
EBV, malaria, TB, typhoid
congestive causes of splenomegaly
hepatic cirrhosis
portal/splenic vein thrombosis
cardiac failure
haematological causes of splenomegaly
lymphoma/leukaemia
haemolytic anaemia
myeloproliferative disorders
inflammatory conditions that can cause splenomegaly
rheumatoid arthritis
SLE
causes of hyposplenism
splenectomy
coeliac disease
sickle cell
sarcoidosis
feature of hyposplenism
Howell-jolly bodies
what do people need to be immunised against after a splenectomy
pneumococcus
what is lymphoma
malignant lymphocytes that accumulate in the lymph node
subdivisions of lymphoma
Hodgkin lymphoma
Non-Hodgkin lymphoma
symptoms of lymphoma
painless, non-tender, rubbery/soft, asymmetrical lump
NOT TETHERED
fever, night sweats, weight loss, itch, pain, fatigue
presentation of a viral lymphadenopathy
tender, hard and smooth lymph node
presentation of a bacterial lymphadenopathy
tender, hard and smooth lymph node with skin inflamed
how would a metastatic lymphadenopathy present
non-tender, hard lymph node with an irregular surface
TETHERED
how is a lymphadenopathy investigated
FNA or core biopsy
what investigation can be done to sub classify a confirmed lymphoma
immunohistochemistry
4 types of Hodgkin disease
nodular sclerosis
lymphocyte rich
mixed cellularity
lymphocyte depleted
what cell type is associated with Hodgkin disease
reed Sternberg cells
what immunomarker is +ve in non-hodgkin lymphoma
CD20
what immunomarker is +ve in reed Sternberg cells (Hodgkin lymphoma)
CD30 and CD15
two types of non-hodgkin lymphoma
T cell
B cell
which type of non-hodgkin lymphoma is most common
B cell
what is a B cell non-hodgkin lymphoma divided into
low grade B cell
high grade B cell
how is a lymphoma staged
- one group of glands above diaphragm
- more than one group of glands either above or below diaphragm
- both above and below the diaphragm
- extra nodal disease
what tissue is the spleen derived from
mesoderm
weight of average spleen
150g
