Benign WBC Disorders Flashcards
derived visual appearance of “buffy coat”
White Cell
Leukocyte or leucocyte: Greek leucos
leucos= white
leukois the original German spelling
leucois the anglicized spelling.
Term coined by Virchow to indicate a malignancy which greatly increases the “Leuko” fraction of the blood, but now also includes aleukemicleukemias
Leukemia
Aleukemic leukemia
leukemia in which the leukocyte count is normal or below normal; it may be lymphocytic, monocytic, or myeocytic.
Solid tumors derived from lymphoid tissue that primarily involve lymph nodes and peripheral organs
lymphoma
Myeloid Disorders (leukemias)
precursors of erythroid, granulocytic, monocytic and megakaryocytic series
Granulocytes include neutrophils, eosinophils and basophils
Myeloid Cells (Myeloid: Erythroid ratio):
granulocytes and monocytes only
Nodes with low grade non-Hodgkin lymphoma
Tends to involve multiple lymph nodes (“matted” nodes)
High grade Non-Hodgkin’s lymphoma (NHL) tends to involve a single node, localized group of nodes or extranodalsite
Nodes involved with lymphoma usually appear fleshy tan and are rubbery firm
Plasma is made up of
it is 55% of total blood volume
made of:
91% water
7% blood proteins (fibrinogen, albumin, globulin)
2% nutrients (aa, sugars, lipids), homrones (erythropoietin, insulin, etc), electrolyets (sodium, potassium, calcium etc)
Cellular components of blood is made up of
45% of total blood volume
made of:
buffy coat - white blood cell about 9000 per mm3 of blood and platelets about 250000 per mm3 of blood
RBCs - about 5 million per mm3 of blood
anemia in cbc shows up as
mildly elevated WBC count due to lymphocytosis and an elevated erythrocyte sedimentation rate
Paul Ehrlich, M.D.
(Virchow’s PathologieInstitute, 1878 –1888) uses basic and acidic aniline dyes on blood smears to describe and name peripheral blood WBCs
Dimitri Romanovsky, M.D.
1891 reported use of eosin and methylene blue to identify malaria parasites in red cells —“Romanovskystains”
Most common types used to stain peripheral blood white cells
Wright Giemsa
wright stain
looking at dna
Giemsa stain
looking for parasites
Hematopoiesis
nk cell
hematopoietic stem cell>multipotent progenitor>early progenitor with lymphoid protential> pro nk cell>pre nk cell>nk cell
Hematopoiesis
b cell
hematopoietic stem cell>multipotent progenitor>early progenitor with lymphoid potential>pro b cell (lymphopoiesis)>pre b cell> b cell
Hematopoiesis
t cell
hematopoietic stem cell>multipotent progenitor>early progenitor with lymphoid potential> pro t cell (lymphoiesis)> pre t cell >t cell
Hematopoiesis
neutrophil
hematopoietic stem cell>multipotent progenitor>earl progenitor with myeloid potential>CFU-mix>cfu-g>myeloblast>neutrophil
Hematopoiesis
monocyte
hematopoietic stem cell>multipotent progenitor>earl progenitor with myeloid potential>CFU-mix>cfu-m>monoblast>monocyte
Hematopoiesis
Eosinophil
hematopoietic stem cell>multipotent progenitor>earl progenitor with myeloid potential>CFU-mix>cfu-eo>eosinophilic blast>eosinophil
Hematopoiesis
baophil
hematopoietic stem cell>multipotent progenitor>early progenitor withmyeloid potential>CFU-bme>cfu-b> basophilic blast>basophil
Hematopoiesis
platelets
hematopoietic stem cell>multipotent progenitor>early progenitor withmyeloid potential>CFU-bme>cfu-mg>megakaryoblast>platelets
Hematopoiesis
erythrocyte
hematopoietic stem cell>multipotent progenitor>early progenitor withmyeloid potential>CFU-bme>cfu-e>erythroblast>erythrocyte
hematopoiesis at birth
bone marrow
hematopoiesis at 70
most to least
vertebral and pelvis
sternum
ribs
lymphnodes
femur
red cell myelopoiesis
myeloid stme cell>pronormoblast>basophilic normoblast>polychromic normoblast>orthochromic normoblast>red cell
megakaryocyte myelopoiesis
myeloid stem cell>megakaryoblast>promegakaryocyte>megakaryocyte
monocyte myelopoiesis
myeloid stem cell>monoblast>promonocyte>monocyte
mature basophil myelopoiesis
myeloid stem cell
myeloplast type I
myeloblast type II
promyelocyte
basophil myelocyte
basophil metamyelocyte
basophil band
mature basophil
segmented neutrophil meyloposiesis
myeloid stem cell
myeloplast type I
myeloblast type II
promyelocyte
neutrophil myelocyte
neutrophil metamyelocyte
neutrophil band
segmented neutrophil
mature eosinophil myelopoiesis
myeloid stem cell
myeloplast type I
myeloblast type II
promyelocyte
eosinophil myelocyte
eosinophil metamyelocyte
eosinophil band
mature esoinophil
CD4+ cell maturation overview
Lymphoid Stem cell in bone marrow>thymus>t precursor lymphoblast>naïve tcell>blood>CD4+>antigen presentation>node paracortex>t immunoblast>blood>effector tcell
Cd8+ maturation overview
Lymphoid Stem cell in bone marrow>thymus>t precursor lymphoblast>naïve tcell>blood>CD8+>antigen presentation>node paracortex>t immunoblast>blood>memory tcell
T precursory lymphoblast and t lymphoblastic lymphoma/ leukemia
Location - thymus/bone marrow
nuclear marker - tdt+
markers - cd1a, cd7, cd3, cd4-, cd8-
Naïve t cells
location - thymus
markers - cd1a, cd7, cd2, cd3, cd4+, cd8+
where do peripheral t cell lymphomas arise
node paracortex
plasmacytoid lymphocyte and lymphoplasmacytic lymphoma overview
lymphoid stem cell in bone marrow> bprecursor lymphoblast>blood>naïve b cell (in primary follicle or mantle zone>antigen presentation> folligular/germinal center>follicular b blast>node paracortex>b immunoblast>blood> plasmacytoid lymphocyte
Plasma cell and myeloma overview 1st way
lymphoid stem cell in bone marrow> bprecursor lymphoblast>blood>naïve b cell (in primary follicle or mantle zone>antigen presentation> folligular/germinal center>follicular b blast>node paracortex>b immunoblast>marginal zone>memory b cell> marrow (blood?)> plasma cell
plasma cell and myeloma overview 2nd way
lymphoid stem cell in bone marrow> bprecursor lymphoblast>blood>naïve b cell (in primary follicle or mantle zone>antigen presentation> follifular/germinal center>follicular b blast>centroblast>centrocyte>marginal zone>memory bcell> marrow (blood?)>plasma cell
plasma cell and myeloma overview 3rd way
lymphoid stem cell in bone marrow> bprecursor lymphoblast>blood>naïve b cell (in primary follicle or mantle zone>antigen presentation> follifular/germinal center>follicular b blast>centroblast>centrocyte>marrow (blood?)>plasma cell
b precursor lymphoblast and be lymphoblastic leukemia/lymphoma
location - bone marrow
nuclear markers - tdt+ and pax 5
markers - cd10,19,79a
naïve b cell and mantle cell lymphoma
location - blood/primary follicle or mantle zone
nuclear markers - bcl2 and pax5
markers - cd10,19,20,79a,5, sigm and sigd
follicular b blast and burkitt lymphoma
location - follicular/ germinal center
nuclear markers - bcl6 pax5
markers - CD10,CD19, CD20,CD79a, sIgM
b immunoblast and large b cell lymphomas
location - node paracortex
nuclear markers - pax 5
markers - cd20,79a and sigm
centroblast
location - follicular/germinal center
nuclear markers - bcl6 pax5
markers - cd10, 20, 79a sig?
centrocyte
location - follicular/germinal center
nuclear markers - bcl6 pax5
markers - cd10,20,79a,sig g and sigm
memory b cell
location - marginal zone
nuclear markers - pax5
markers - cd20,38,79a, and sigm
plasmacytoid and lymphocyte lymphoplasmacytic lymphoma
location - blood
nuclear markers - pax5
markers - cd20 79a 38 138 and cigm
plasma cell and myeloma
location - blood? and marrow
nuclear markers - none
markers - cd79a 38 138 and cig gamde
Monocyte =
circulating macrophage or histiocyteprecursor
Count and normal range per 1000 bone marrow cells
myeloblast
14
0.1-0.7
Count and normal range per 1000 bone marrow cells
Promyelocyt
29
1.9-4.7
Count and normal range per 1000 bone marrow cells
myelocyte
103
8.5-16.9
Count and normal range per 1000 bone marrow cells
band (stab) neutrophil
116
9.4-15.4
Count and normal range per 1000 bone marrow cells
metamyelocyte
91
7.1-24.7
Count and normal range per 1000 bone marrow cells
segmented neutrophil
106
9.4-15.4
Count and normal range per 1000 bone marrow cells
lymphocyte
111
8.6-23.8
Use “Romanovsky” stains on
air-dried thin smears of blood.
The “Manual WBC differential” is performed by examining
The “Manual WBC differential” is performed by examining
The relative number of each typeof WBC is expressed as %
of the total white cell population.
count and normal range per 100 white cells in peripheral blood
basophil
1
0-3
count and normal range per 100 white cells in peripheral blood
segmented neutrophil
61
45-79
count and normal range per 100 white cells in peripheral blood
band neutrophil
2
0-5
count and normal range per 100 white cells in peripheral blood
lymphocyte
24
16-47
count and normal range per 100 white cells in peripheral blood
monocyte
8
0-9
count and normal range per 100 white cells in peripheral blood
eosinophil
4
0-6
Hyper-segmentation
PMNs with 5 or more lobes indicate; seen with megaloblastic anemias, myeloproliferativedisorders, and some chemotherapy
Toxic granulation and vacuolization
increased and prominent azurophilic(primary) granules and cytoplasmic vacuoles; seen with infections
Left shift
An absolute increase in neutrophils with an increase in bands +/-metamyelocytesor myelocytes-seen in infections and leukemias
Reactive changes in neutrophils
Neutrophils containing coarse purple cytoplasmic granules (toxic granulations) and blue cytoplasmic patches of dilated endoplasmic reticulum (Döhlebodies, arrow) are observed in this peripheral blood smear prepared from a patient with bacterial sepsis
Changes in WBCs in Peripheral Blood
Relative change
in one type of white blood cell WBC expressed as a %of overall number WBCs usually doesn’t mean much
What matters for each WBC type is the “absolute’ count or % of total multiplied by the total WBC count; e.g.,
Changes in WBCs in Peripheral Blood
Absolute neutrophil count
Absolute Neutrophil Count =% NeutrophilsX total WBC count
Absolute neutrophils = 46% X 10,000 cell/microliter
= 4,600 neutrophils/uL
Adult Reference Ranges for Blood Cells
Platelets (×103/μL)
150-450
Adult Reference Ranges for Blood Cells
White cells (×103/μL)
4.8-10.8
Adult Reference Ranges for Blood Cells
Granulocytes (%)
40-70
Adult Reference Ranges for Blood Cells
Neutrophils (×103/μL)
1.4-6.5
Adult Reference Ranges for Blood Cells
Lymphocytes (×103/μL)
1.2-3.4
Adult Reference Ranges for Blood Cells
Monocytes (×103/μL)
0.1-0.6
Adult Reference Ranges for Blood Cells
Eosinophils (×103/μL)
0-0.5
Adult Reference Ranges for Blood Cells
Basophils (×103/μL)
0-0.2
Adult Reference Ranges for Blood Cells
Red cells (×106/μL)
4.3-5.0, men; 3.5-5.0, women
Common Reference Range Absolute Neutrophils
Birth
1-7 days
8-14 days
15 days-1 month
2-5 months
6 months-5 years
6-15 years
Adult
Birth 6.0-26.0 1-7 days 1.5-10.0 8-14 days 1.0-9.5 15 days-1 month 1.0-9.0 2-5 months 1.0-8.5 6 months-5 years 1.5-8.5 6-15 years 1.5-8.0 Adult 1.7-7.0
Lifespan of WBCs in Peripheral Blood
Neutrophils (Granulocytes):
1 -48 Hours
Note:
Lifespan of WBCs in Peripheral Blood
Eosinophils:
1 –48 hours (average 8 hours)
Note:
Lifespan of WBCs in Peripheral Blood
Lymphocytes:
Hours to days (B-cells)
Days to years (T-cells)
Changes in Peripheral Blood WBCs Associated with “Disease”
Segmented neutrophils (granulocytes) includes bands
- Granulocytopenia≃Neutropenia
- Granulocytosis
- Leukemoidreaction
- Leukoerythroblastosis
Changes in Peripheral Blood WBCs Associated with “Disease”
Eosinophils
Eosinophilia
Changes in Peripheral Blood WBCs Associated with “Disease”
Lymphocytes
- Lymphopenia
- Lymphocytosis
- Atypical (activated) lymphocytes
Changes in Peripheral Blood WBCs Associated with “Disease”
What about, basopenia, basophilia, monocytosis, monocytopeniaand eosinophilopenia?
Can be a hint to underlying disorders !!!!
Neutrophilicleukocytosis
Acute bacterial infections, especially those caused by pyogenicorganisms; sterile inflammation caused by, for example, tissue necrosis (myocardial infarction, burns)
Eosinophilicleukocytosis
eosinophilia
Allergic disorders such as asthma, hay fever, helminthicparasitic infestations; drug reactions; certain malignancies (e.g., Hodgkin and some non-Hodgkin lymphomas); automimmunedisorders (e.g., pemphigus, dermatitis herpetiformis) and some vasculitides; atheroembolicdisease (transient)
Basophilic leukocytosis
basophilia
Rare, often indicative of a myeloproliferativedisease (e.g., chronic myeloid leukemia)
Monocytosis
Chronic infections(e.g., tuberculosis), bacterial endocarditis, rickettsiosis, and malaria; autoimmune disorders(e.g., systemic lupus erythematosus); inflammatory bowel diseases(e.g., ulcerative colitis)
Lymphocytosis
Accompanies monocytosisin many disorders associated with chronic immunological stimulation (e.g., tuberculosis, brucellosis); viral infections (e.g., hepatitis A, cytomegalovirus, Epstein-Barr virus);Bordetellapertussisinfection
granulocyte hemopoietic pools
bone marrow pool - prolif and mature>storage
peripheral blood - 50% storage and 50% functional
thrombocyte hemopoietic pools
bone marrow is all prolif and mature
peripheral blood - storage is 30% and functional is 70%
erythrocyte hemopoietic pools
bone marrow is all prolif an dmature
peripheral blood is all functional
Mechanisms and Causes of Leukocytosis
INCREASED PRODUCTION IN THE MARROW
Chronic infection or inflammation
(growth factor-dependent)
Paraneoplastic
(e.g., Hodgkin lymphoma; growth factor-dependent)
Myeloproliferativedisorders
(e.g., chronic myeloid leukemia; growth factor-independent)
Mechanisms and Causes of Leukocytosis
INCREASED RELEASE FROM MARROW STORES
endotoxemia
infection
hypoxia
Mechanisms and Causes of Leukocytosis
DECREASEDMARGINATION
exercise
catecholamine
Mechanisms and Causes of Leukocytosis
DECREASED EXTRAVASATION INTO TISSUES
glucocorticoids
Neutrophils and their precursors are distributed in five pools…
bone marrow - precursor pool and storage pool
peripheral blood - marginating pool and circulating pool
tissues - tissue pool
peripheral blood is only the circulating pool
Leukemoid Reaction
A marked elevation in white cell count
(usually > 20,000/uL) that
Simulates chronic myelogenousleukemia
high WBC count and immature precursors in blood
Leukocyte alkaline phosphatase score elevated
Low scores inChronic Myelogenous Leukemia
Low scores inChronic Myelogenous Leukemia
(Can also be low in paroxysmal nocturnal hemoglobinuria, thrombocytopenic purpura, and hereditary hypophosphatasia)
Leukocyte alkaline phosphatase score elevated
(Can also be high in polycythemia vera, myelofibrosis, aplastic anemia, hairy cell leukemia and Hodgkin disease)
Leukoerythroblasticreaction
•Presence of immature granulocytes
and erythroid precursors in the blood
- Commonly seen in:
- Severe hemolytic anemia
- Bone marrow infiltration
- metastatic tumor
- granulomas
- infiltrative process (fibrosis)
- Chronic myeloproliferativeneoplasms
- particularly primary myelofibrosis
Critical Value for Neutropenia(Granulocytopenia)
Critical value generally quoted:
absolute count
The lower the absolute neutrophil count
the greater the risk of infection
- Infections are the most common cause of acquired neutropenia
- Drugs the most common cause of clinically significant neutropenias
Agranulocytosis
severe neutropenia, usually caused by drugs
Neutropenia
pathogenesis
- Decreased or ineffective production
- Inherited, such as severe congenital neutropenia e.g. Kostmannsyndrome (severe congenital neutropenia, autosomal recessive type 3)
- Acquired, such as acquired aplastic anemia, myelodysplastic syndrome, nutritional deficiencies
Neutropenia
accelerated removal or destruction
- Immunologic disorders
- Splenomegaly
- Severe infections, such as overwhelming bacterial infection
Peripheral Blood Eosinophilia: relative & absolute
Relative Eosinophilia:>3% total wbcdifferential count
Absolute Eosinophilia:Total Eosinophils >0.5 x 109/L
(Variable depending on laboratory, institution & geographic location)
Absolute Eosinophilia further subdivided into:
Mild Eosinophilia 0.35-0.90 x 109/L
Moderate Eosinophilia1.00-5.00 x 109/L
Marked Eosinophilia>5.00 x 109/L
Eosinophilia
Screening ambulatory North American outpatients (1997)
0.1% Had absolute eosinophil counts of >0.7 x 109/L.
Etiology% Patients with Eosinophilia
Unknown36 Seasonal allergy/allergic rhinitis29 Asthma14 Eczema/dermatitis9 Cancer4 Drug allergy3 Parasitic disease2
eosinophilia
Outside United States
Screening Asian young males (military service in Singapore)
5% had absolute eosinophil counts >0.7 x 109/L
Etiology% Total Patients with Eosinophilia
Helminthiasis49
Atopy-Allergy28
Helminth + Atopy16
Unknown7
Lymphocytosis
Reference range values:
Total (absolute) Lymphocytes x 109/L
Ages 6 -11 yrs(male & female) 1.5 -6.5
Ages 12 -15 yrs(male & female) 1.2 -5.2
Adult (male & female) 0.9 -2.9
Total lymphocytes normal adults
USC Clinical Laboratories; Flow Cytometry Section
Absolute lymphocyte count
Mean 2.720; Range 1.359 -3.479 ×109/L
Relative(%) lymphocyte count
Mean 40; Range 20 –47
Lymphocyte SubpopulationsCirculating Lymphocytes
T-cell Peripheral
Antibody%Range Absolute /μL range
CD3+
60 -90
952 –2,745
Lymphocyte SubpopulationsCirculating Lymphocytes
Antibody%Range Absolute /μL range
T-cell helper
CD4+
32 -56
518 –1,605
Lymphocyte SubpopulationsCirculating Lymphocytes
Antibody%Range Absolute /μL range
T cell cytotoxic
CD8+
17 -40
367 -1,072
Lymphocyte SubpopulationsCirculating Lymphocytes
Antibody%Range Absolute /μL range
B cell peripheral
CD19
4-20
91 -295
Lymphocyte SubpopulationsCirculating Lymphocytes
Antibody%Range Absolute /μL range
nk cell
CD56+/16+ 4
-18
58 -335
Most ( > 80%) of Circulating Lymphocytes are
t cell
Normal CD4/CD8 ratio
1:1 to 4:1
Normal kappa/lambda ratio (bs)
1:1 to 2:1
Infectious Mononucleosis
virus
Acute infectious mononucleosis: Transient disease associated with Epstein Barr virus (EBV)
Infectious Mononucleosis
clinical findings
Severe fatigue
Sore throat
Lymphadenopathy
Lymphocytosis due to variant forms (Downey cells)
•Lymphocytosis is transient, lasting a few days to weeks
•[An infectious mononucleosis-like picture rarely seen in CMV (cytomegalovirus) infection, viral hepatitis, herpes simplex infections, serum sickness illness and drug reactions]
Epstein Barr virus (EBV) infects
B cells
EBV glycoprotein binds CD21/CR2 (C3d complement receptor)
May be asymptomatic in children
Sore throat, fever, febrile rash and lymphadenopathy
Can develop hepatitis, anemia (anti-i), thrombocytopenia, splenomegaly
Subsequent B & T cell response after ebv infects b cells
Cytotoxic/supressorCD8+ T cells and CD 16+ NK cells soon predominate in tissues and blood destroying infected B cells (with WBC of 12,000-18,000 cell/uland atypical lymphocytes)
Monospottest
for ebv
sensitive fairly specific heterophileantibody test positive in 1-2 weeks in 85% (Serum absorbed with guinea pig kidney still binds horse erythrocytes)
Epstein Barr-Virus antibodiesto capsidantigen
for heterophilenegative cases
Differential HeterophilAbsorption test: cow erythrocytes
+/guinea pig erythrocytes -highly specific, but less sensitive, for the diagnosis (with typical clinical presentation and positive Monospot, not necessary)
Paul-Bunnellreaction
(1932) heterophileantibodies to sheep red cells
Atypical lymphocytes in infectious mononucleosis
The cell on the left is a normal small lymphocyte with a compact nucleus filling the entire cytoplasm. In contrast, an atypical lymphocyte on the right has abundant cytoplasm and a large nucleus with fine chromatin.
“Atypical” lymphocytes
Atypical = larger (more cytoplasm); nucleoli in nuclei; cytoplasm indented by surrounding RBC’s. Atypical lymphocytes often associated with infectious mononucleosis –“Mono”.
LymphocytopeniaLymphocytes Decreased Below Reference Range
Reference values: Total lymphocytes adults
(USC Clinical Laboratories; Flow Cytometry Section)
Absolute lymphocyte count
Mean 2.720; Range 1.359 -3.479 ×109/L
Relative (%) lymphocyte count
Mean 40; Range 20 -47
Absolute lymphocytopenia(no other abnormality) detected by automated hematology analyzer testing:
Perform a microscopic examination of a peripheral blood smear to examine the lymphocyte morphology
Absolute lymphocytopeniawith Hemogramabnormality (anemia,
thrombocytopenia or leukopenia without known clinical cause)
Perform a bone marrow aspirate and biopsy
Absolute lymphocytopenia+ suspect immune deficiency
Flow cytometry immunophenotyping
Serum protein concentration
Serum protein electrophoresis
Quantitative serum immunoglobulins
LymphocytopeniaCommon Causes
Chemotherapy or irradiation therapy
Cortisone “Steroid” therapy
Administration of erythropoietin
Pregnancy
Diseases associated with lymphocytopenia
AIDS Hodgkin's disease Idiopathic or acquired aplasticanemia Acute bacterial infection Cancer stomach, ovary and breast Systemic lupus erythematosus Viral infections on occasion
dark zone
proliferation of b cells and somatic hypermutation
Basal light zone
positive slection for binding to antigen on follicular dendritic clels
apical light zone
generation of memory cells and plasma cell precursors and class switching
lymph node capsule
Subcapsularsinus
MonocytoidB cells
IgGor IgM+. IgD-, BCL2
Secondary Follicle
Germinal Center (BCL2-)
B-blast (small noncleaved)
sIgM+, transient
Centroblast(large noncleaved)
sIg-, persistent
Centrocyte(small/large cleaved)
sIgG+, persistent
Mantle Zone
mostly naive
marginal zone
IgM+, IgD-(memory cell)
Primary Follicle (naïveB-cells)
IgM+,IgD+,CD5-/+,BCL2+
Lymphadenopathy: definition
Painlessenlargement of a lymph node or group of nodes
Lymphadenopathy: Applies to any enlargement of lymph node(s)
- Infection most likely cause of lymphadenopathy, particularly in children
- Viral infection most likely cause of lymphadenopathy
- Supraclavicular and axillary lymph node enlargement is more concerning
- Lymph node > 4 centimeters most likely is malignant
- Hemophagocyticlymphohistiocytosis
Hemophagocyticlymphohistiocytosis
rare familial or acquired over-activation of histiocytesvia CD8+ lymphocytes that leads to lymphadenopathy and hepatosplenomegaly from hemophagocytosisleading to pancytopenia; along with other clinical manifestations (rash, fever, etc.)
Major Cause Adenopathy > Age60
Metastatic Carcinoma
causes of adenopathy
Reactive
–general immune response (local/systemic)
–specific diseases
Uncertain cause: Sarcoidosis
Primary Neoplasms: Malignant
Lymphomas, etc
Secondary Neoplasms: Metastasis
location of adenopathy in adults
head and neck - 55%
supraclavicular - 1 %
axillary - 5%
inguinal - 14%
localized - 75%
Acute Nonspecific Lymphadenitis:
Swollen, edematous tender (painful)with distended capsule
Associated with acute bacterial infection of a localized body site resulting acute lymphadenitis affecting the regional lymph nodes draining the site
Most common node groups involved are cervical and mesenteric
May become suppurativeand form draining sinus
Chronic Nonspecific Lymphadenitis
Enlarged but painless; capsule is proportionally enlarged. Nodes are palpable (> 2cm).
3 patterns of chronic nonspecific lymphadenitis
Stimulus B-cell populations
Stimulus T-cell populations
Prominence of lymphatic sinusoids:
Stimulus B-cell populations
Follicular Hyperplasia expansion of the germinal centers with increase in tingiblebody macrophages; Specific causes include: Rheumatoid Arthritis, Toxoplasmosis, early stages HIV
Stimulus T-cell populations
ParacorticalHyperplasia Expansion of T-cell rich paracorticalregions; infectious mono, acute viral infections, following vaccinations, reactions to Dilantin.
Prominence of lymphatic sinusoids:
Sinus HistiocytosisHyperplasia of macrophages lining sinuses, e.g. in axillary nodes draining a region of breast cancer.
Reactive Hyperplasia
Manifestations of immune response in lymph node
B cell transformation/
proliferation
follicle
Reactive Hyperplasia
Manifestations of immune response in lymph nnode
T cell transformation/
proliferation
paracortex
Reactive Hyperplasia
Manifestations of immune response in lymph node
Histiocyterecruitment/ activation
sinuses
Reactive Hyperplasia:
Follicular Hyperplasia
B CD20
Follicular hyperplasia
B cell transformation
+ proliferation –follicles
Reactive Hyperplasia:
Diffuse Paracortical
T cell transformation
+ proliferation –Paracortex
Diffuse hyperplasia
TCD3
Cat Scratch Disease
- Self-limited lymphadenitis usually of head and neck
- Bartonellahenselae
- Cat scratch, splinter or thorn
- Primarily in children
- Rarely encephalitis, osteomyelitis, or thrombocytopenia
- Initially, sarcoid-like granulomas
- Laterstellate necrotizing granulomas
follicular hyperplasia
low power view
reactive follicle and surrounding mantle zone. The dark-staining mantle zone is more prominent adjacent to the germinal-center light zone in the left half of the follicle. The right half of the follicle consists of the dark zone.
follicular hyperplasia high power view
of the dark zone shows several mitotic figures and numerous macrophages containing phagocytosed apoptotic cells (tingiblebodies).
