Spleen Flashcards
Anatomy of the spleen
A specialized connective tissue composed of a 3 dimensional —————- serving as ______ in d path of blood circulation
reticular meshwork
filter
Anatomy of the spleen
Selectively clears blood of cells, micro organisms and antigens in ________ called _________
Stroma meshes
filtration beds
Sinusal spleen: a.k.a ________ spleen seen in ___________ and accounts for less than _______% of body weight.
defence
cats and humans
0.25
Non-sinusal or _______ spleen are seen in _________.
________ and _______ are fibromuscular.
storage
herbivores
Capsules and trabeculae
Sinusal spleen:
The immunologically active ______ pulps are particularly prominent where _______,_______, and _______ predominate.
white
lymphocytes, macrophages and APCs
Non-sinusal
Usually (light or heavy?) with ______ and thus perform ____________.
May make up ____% of body weight
Heavy
stored blood
internal transfusion
1
Spleen receives ____ to _____% of cardiac output or about _____mils/min in humans
1; 10
300
Spleen
Weighs an average of _____g in humans and only ___g when totally drained of blood.
135
80
Spleen
Involution occurs with ______
- weighs about _____g in elderly
age
70
Splenic structure
The capsule is _________, covered on the external surface by (ciliated or non-ciliated?) _____ ————
fibromuscular
Ciliated; cuboidal
mesothelium
Splenic structure
On the medial surface is a ridge called the _______ through which blood vessels traverse the spleen
hilus
Splenic structure
Richly branched _______ project into the splenic pulp carrying ______________ and efferrent lymphatics while dividing the pulp into compartments
trabeculae
splenic artery and vein
Splenic structure
The capsule is fibromuscular, covered on the external surface by ciliated cuboidal mesothelium(contributing to its high _____________ by _________)
splenic haematocrit
pumping fluid out
Splenic structure
The nerve supply accompanies the arterial branches, terminating deep in the pulp as _______ axons that cause the pulp _______ to ______ and _______
adrenergic
meshwork
expand and contract.
Splenic structure
The primary cellular element of the pulp is the (branched or non-brnached?) fibroblastic ______ cells which produces slender ______ fibers(_______ fibers)
branched
reticular
collagen; reticular
Splenic structure
These collagen fibres(type ____ collagens) together with the ______ cells form the meshwork of the pulp Called the _______ which is what ———-
4
reticular
reticulum
filters blood
the reticulum which is what ______(_________)
filters blood
filtration bed
the ________ which is what filters blood(filtration bed)
reticulum
Structure of the filtration bed
There are two main distinguishable areas of the filtration bed
1._______
2.___________
white pulp
red pulp
White pulp:
from the _____, the ______ traverses the stroma carrying with it a branch of the splenic artery (______ artery)
As this artery enters the meshwork of the spleen, its immediately surrounded by distinct layer of reticulum called the _______________. Which itself is encapsuled by the ______________
hilus; trabeculae
central
periarterial lymphatic sheath
circumferential reticulum
periarterial lymphatic sheath is not encapsuled by the reticulum
T/F
F
It is
The periarterial lymphatic sheath is rich in ????
T-lymphocytes
Along the length of the PALS are (small or large?) (flat or round?) follicles scattered on its peripheral surface.
These are ovoid accumulation of ________ which appears as _______ on the cut surface of the spleen
Small
Round
B lymphocytes
whitish dots
The follicle is made up of central _______ and outer ________ zones
germinal; marginal
As the central artery branches, it _________ as it goes, so likewise is the ______
diminish in size
PALS
Function of the white pulps
Majorly __________ and _________ ———— and accessory cells from circulation
clears and concentrate
lymphocytes
Function of the white pulps
________ that traffic to and fro the white pulp are the circulating pool
Lymphocytes
On activation the lymphocytes may remain in the spleen to sustain primary or secondary immune response
T/F
T
Function of the white pulps
Lymphoid nodules become enlarged as they recruit more ____-lymphocytes from the blood and ———- zone and moves ____ wards forming the ___________
B
mantle
in
germinal center
The central arterioles now terminate in the _______ zone as it enters the ____ pulp
marginal
RED
The ________ and ———— thus constitutes the white pulp
PALS and lymphoid nodules
B and ____ cells have ___ hours to interact as B cells on their way to the _____ center traverse the _______
T
few; germinal; PALS
B and T lymphocytes exit the spleen via the ______________
efferent lymphatics
RED PULP
Consists of the meshwork called ________________ along with ________
splenic cord of Bilroth
splenic sinuses
Arterial vessels that runs from the center of the PALS supply the ______ zone and ____ pulp
marginal
red
RED PULP
Arterial vessels that runs from the center of the PALS supply the marginal zone and red pulp
These vessels terminate as arterial capillaries and vessels with ______-like flares with (narrowed or widened?) ______________ as the blood runs through numerous interwoven ________
trumpet
widened
endothelial slits or pores
filtration beds
Functions of the spleen
Non immune function: a _____ of platelets are stored in the spleen, pooling, pitting
third
Functions of the spleen
Immune function: ———-, ______ , and _________
tuftin, primary and secondary
Functions of the spleen
Immune function
Large fraction of circulating _____ pool are marginated in the spleen.
(Slow or Fast?) transit of blood in the red pulp allows close contact of ______ with antibody and complement coated cells and microorganisms and senescent cells entrapped
neutrophils
Slow ; macrophage
Half of of platelets are stored in the spleen, pooling, pitting
T/F
F
a third of platelets
Hypersplenism
In 1899, chauffard proposed that increased splenic activity results in ________
This served as the basis for the first ever ________ in 1910 by Suthaland and Burghard in a patient with __________
haemolysis
splenectomy
hereditary spherocytosis
The normal and abnormal function of the spleen is traceable to its two major functions:
__________ and _______ of blood in the red pulp and __________ in the white pulp.
Filtration and immune surveillance
antibody synthesis
Hypersplenism occurs when these functions are
- appropriately increased as in _____ or _____, or
- inappropriately increased as in ————
Hereditary spherocytosis , or immune Thrombocytopenic purpura
portal hypertension
Hypersplenism
As enunciated by Darmalek: hyperplenism is usually associated with _______________, causes ________,with compensatory __________ and is corrected by ______
splenomegally
cytopaenias
BM hyperplasia
splenectomy
Pathogenesis of hypersplenism
Ideally spleen serves to filter senescent red cells by passing _____% of blood flow through the ____________ mesh of the red pulp studded with _______.
The blood then reenters the circulation via (narrow or wide?) slits measuring _______, in the endothelium of the venous sinuses.
10
non endothelialized
macophages
Narrow
1-3 um
Pathogenesis of hypersplenism
With ————— or __________, spleen may become over worked with consequent _________ and then __________ for ___________
red cell membrane defects or immune disorders
hypertrophy
sequester normal cells for destruction.
Splenomegally due to variety of causes usually increases the ____________________ causing inappropriate __________ of both normal abnormal cells, therefore cytopaenia results
proportion of blood channeled through the red pulp
hypersplenic sequestration
Causes of splenomegally
Idiopathic:_______
Hereditary disorders: ____,______,________
TSS
HS, CH, thalassemias
Causes of splenomegally
Connective tisssue disorders: ______,
Metabolic disorders:_______, glycogen storage disease, _____,______
SLE
amyloidosis
neimann picks, gauchers
Causes of splenomegally
Malignancies: _____,__________, hairy cell leukamias,cll
Infections: viral, fungal, parasitic(_______)
cml,myelofibrosis
leishmaniasis
Causes of splenomegally
Cardio-vascular: CHF, _______, _________________ obstruction, liver chirrosis
budd-chiari
splenic/portal vein
Tropical splenomegaly syndrome (TSS)
Aka ____________
Follows immunological ___________ due to repeated ________ over a (short or long?) period of time
Hyperactive malarial splenomegaly
over-stimulation
malarial infection
Long
Tropical splenomegaly syndrome (TSS)
Seen in malaria endemic areas(_______,______) Its characterized by :
Africa, india
Tropical splenomegaly syndrome (TSS)
Its characterized by :
__________ enlargement
______megaly
marked elevation in serum Ig____ level
elevated anti malarial ______
marked ___________
marked ________ and _________ infiltration of the pulp
- blood smear for malaria parasite is usually (positive or negative?)
massive spleen
hepato
M; antibodies
dilated sinusoids
erythrophagocytosis and lymphocyte
Negative
Clinical features of TSS
may include: _______ ,_________
Anaemia
Thrombocytopaenia
Management of TSS
- exclude all other causes of splenomegaly
2.____________ followed by prolonged ____________
Antimalarial drug
antimalarial prophylaxis
The spleen is the site for primary extramedullary hematopoesis
T/F
T
The capsule of the spleen is _____ and _________, allowing it to ______, or else it will rupture
Fibrous
Elastic
Expand
PCV is lower in the spleen than other places
T/F
F
Higher
______ follicle is found in the marginal zone
______ follicle is found in the germinal zone
Primary
Secondary
Primary follicle is found in the _______
Secondary follicle is found in the _________
marginal zone
germinal zone
CLASSICAL definition of hypersplenism
??
Is an exaggerated abnormal function of the spleen which usually results in pancytopenia , BM hyperplasia which is corrected after splenectomy
TSS
Long term antimalarial therapy causes reduction of the spleen .
The drug used is ______ (_______)
paludrine
proguanil
CH ???
Cranio facial hyperplasia
Chemical produced by the spleen against encapsulated organisms is ???
Tuftin
