Lymphatic system Flashcards
3 functions of the lymphatic system
maintenance of fluid balance within the tissues
absorption and carriage of water-insoluble fats from the intestine
protection of the body through the generation of an immune response
4 components of the lymphatic system
lymphatic vessels
lymph nodes
spleen
thymus
What do superficial lymphatics follow?
veins
What do deep lymphatics follow?
arteries
Describe cisterna chyli
sac-like structure
right side of L1/2
receives lumbar and interstitial lymph trunks
What does thoracic duct receive?
receives left subclavian and jugular lymphatic ducts
Describe lymph nodes
compact aggregates of lymphoid and supporting connective tissues
microns to mm
distributed throughout body
Lymph nodes function
allows interaction of antigen, APC and lymphoid cells in the generation of an immune response
Where is the spleen?
left upper quadrant
Spleen function
trapping + presenting antigens circulating in the blood
culling old red cells
Surgical sieve approach to splenomegaly
infective
vascular
neoplastic
haematological
immunological
metabolic
Splenomegaly infective causes
bacterial = TB, endocarditis
viral = infective mononucleosis
protozoal = malaria, leishmaniasis
Splenomegaly haematological causes
haemolytic anaemias
Splenomegaly immunological causes
rheumatoid arthritis, sarcoidosis
Splenomegaly metabolic causes
rare inherited enzyme deficiencies eg. Gauchers
Splenomegaly vascular causes
portal hypertension (cirrhosis)
Splenomegaly neoplastic causes
lymphoma, leukaemia, Myeloproliferative disorders
Felty syndrome triad
Rheumatoid arthritis, splenomegaly, neutropenia
4 causes of lymphadenopathy
infective
neoplastic
immunological
metabolic
Lymphadenopathy infective causes
local bacterial infection
infective mononucleosis
TB
HIV
Lymphadenopathy neoplastic causes
primary = lymphoma
secondary = metastatic tumours
Lymphadenopathy immunological causes
sarcoidosis
Lymphoma metabolic causes
thyrotoxicosis
What is meant by immunocompetent cells?
distinguish between normal and altered
Function of primary lymphoid organ
development and maturation of cells
eg. bone marrow
Function of secondary lymphoid organ
trap cells or pathogens
eg. lymph nodes/tonsils/MALT/GALT/spleen
What do GALT and MALT stand for?
gut-associated lymphoid tissue
mucosa-associated lymphoid tissue
4 components of lymphatic/lymphoid system
lymphatic capillaries
lymphatic vessels
nodes
ducts
Describe lymphatic vessels
paired valves (bead-like appearance)
deep and superficial vessels and nodes
lymph flow:
- skeletal muscles
- smooth muscles of large vessels
- thoracic pressure changes
Describe lymph nodes
filter lymph fluid
testing + recognition centres
production/maintenance and distribution of lymphocytes
do not have detoxification function (left to liver + kidneys)
What is Waldeyer’s ring?
ring of lymphatic tissue
formed of:
- 2 palatine tonsils
- pharyngeal tonsil
- lingual tonsil
- tubal tonsils
and intervening lymphoid tissue
