13. Disorders of WBCs Flashcards
If the absolute numbers look ok on a blood count, should you stop there? or is there another test?
may need to test FUNCTION of neutrophils as well as numbers, percentages. can have dysfunction even with normal counts
when to worry about dysfunctional neuts even if absolute counts are ok?
- recurrent bacterial infections
- infections of unusual sites (brain,liver)
- infections with unusual pathogens (fungal)
- Chronic gingivitis or aphthous ulcers
if you have a young kid with recurrent infections and an ok absolute count, what should you be thinking of?
congenital disorder of neutrophils
Leukocyte Adhesion Deficiency. defect of what? sx? tx?
- defect of adhesion and rolling.
- recurrent bacterial infections
- neutrophilia, NO PUS
- tx: stem cell transplant
Hyperimmunoglobulin E syndrome: defect? sx? will be high in what? tx?
- defect of chemotaxis.
- sx are chronic dermatitis (eczema), recurrent staph, candidal infections. may also be facial abnormalities
- High IgE levels
- Tx generally supportive with prophy abx
Chediak-Higashi Syndrome: defect? sx? comorbid condition? tx?
- degranulation defect: abnormal granules with impaired delivery of lysosomal enzymes to phagosomes, result in slow killing.
- recurrent pyogenic (pus) infections
- kids also have partial albinism
Chronic Granulomatous Disease: defect? sx? tx?
- defect with bacterial killing. inability to generate neutrophil oxidative burst that produces ROS and bactericidal agent hypochlorous acid
- recurrent pyogenic infectiosn of skin, lungs, formation of granulomas
- tx with prophy abx
if I see eczema, what should I think?
hyperimmunoglobulin E
myelodysplasia/myelodysplastic syndrome: type of disorder? what will neut count be?
- clonal disorder, dysfunction of neuts
- neut count will be decreased OR normal
- other cell lines (plts, RBCs) may be affected
alcoholism: affect on neutrophilis
decreased motility and phagocytosis
metabolic disorders: affect on neut function?
decr adhesion, motility, phagocytosis.
disorder could be diabetes, uremia, malnutrition, autoimmune
what could a dysplastic PMN look like?
might be bi-lobar rather than with 3-4 lobes
eosinophil: what does it do? is it granular? military analogy?
phagocytic cell, primary function is to kill parasites.
has dense red granules.
also involved in hypersensitivity rxns
“special ops”
what problems associated with a low eosinophil count?
low eosinophil count not clinically sig.
eosinophilia: most common cause globally
parasitic infections
eosinophilia: most common cause in dev countries?
atopic allergic disease
Causes of eosinophilia?
N: neoplasm (Hodgkins, Lymphoma, CML, Primary eosinophilic disorders)
A: Allergies
A: asthma
C: collagen vascular diseases and vasculitis
P: parasitic infection
what is the approach to eosinophilia?
more of a history than any test.
atopy, travel, pets, constitutional symptoms (fever, wt loss), drugs/toxins, autoimmune, connective tissue
eosinophilia: tests to run?
CBC, differential
stools for ova, parasites
connective tissue serology (think rheum process)
bone marrow/tissue biopsy
basophil: function? when is basophilia seen?
uncommon cell. disorders are rare
function in hypersensitivity rxns, releases histamine and leukotriends.
basophilia seen with myeloproliferative disorders (Chronic Myelogenous Leukemia: CML)
monocytes: function? when do they get involved? military analogy?
phagocytes, release granules to kill micro-organisms. involved in more chronic phase of infections.
military: reinforcements
what is monocytosis?
too many monocytes
what can cause monocytosis?
- chronic infections
- bone marrow recovery after chemo
- autoimmune and CT disease
- granulomatous disease (sarcoid)
- malignancy
what are some causes of monocytopenia?
uncommon, but:
severe infections/sepsis
bone marrow failure
hairy cell leukemia (agent orange)
Lymphocyte category includes what types of cells?
B cells, T cells, Natural Killer cells
what do B cells do?
produce antibodies for humoral immunity
what do T cells do?
Generates cell mediated immunity and immunoregulation via helper and suppressor sub-populations
what do NK cells do?
HLA-unrestricted killing
generally, where does maturation of T cells take place?
start in the bone marrow, then either go to periphery as NK cells or to thymus. will become either CD4 of CD8 cell and then go to periphery, become either Memory T cell or Effector T cell.
what happens to the surface markers of B cells as they mature?
gain and lose various surface markers as the cells travel from bone marrow to lymph nodes. some of the maturation process is antigen independent, some is antigen dependent.
what do the surface markers of B cells indicate?
the stage of maturation.
what happens in the germinal center of lymph nodes?
class-switching of B cells
what does ALC stand for
absolute lymphocyte count
what does elevated lymphocyte count indicate
absolute lymphocytosis
on a peripheral smear, what do smudge cells indicate? what are they?
light purple cells that look smudgy, and distort around RBCs. classic for absolute lymphocytosis.
2 categories of lymphocytosis?
non-malignant/non-clonal
malignant/clonal
causes of non-malignant lymphocytosis?
acute infection, chronic infection, hypersens rxn. classic = MONO
causes of malignant lymphocytosis?
chronic lymphocytic leukemia (CLL), acute lymphoblastic leukemia (ALL)
what are atypical lymphocytes/what do they indicate?
big, sort of molding around RBCs, still have nucleus. think MONO.
what is clonality?
confirmation that a malignancy (primary lymphoproliferative disorder) arose from a single cell
define light chain restriction. what does it indicate?
vast change away from normal Kappa:Lambda ratio meaning that a vast number of B cells came from a single lineage. indication of B cell malignancy.
How is malignancy of T cells detected?
T cells don’t have a surface marker that is easily detectable; have to use Western Blot or PCR to determine clonality
Most lymphomas: B cell or T cell derived?
B cell
Lymphocytopenia: definition?
ALC less than 1000
Lymphocytopenia: differential?
congenital
infectious (HIV, TB, malaria)
meds
malignancy: lymphoma/Hodgkins
Lymphocytopenia: once have CBC (established anemia and microcytic anemia) and differential/absolute (established low lymphocytes) what is the diagnostic test to confirm?
bone marrow biopsy
Reed-Sternberg Cell: seen where? indicative of what disease?
bone marrow biopsy
Hodgkin Lymphoma
Pancytopenia: definition?
all three cell lines are affected (WBC, RBCs, platelets)
Pancytopenia: suggestive of what?
bone marrow failure. even if only 2 of 3 cell lines are affected, suggests bone marrow process
pancytopenia: causes? (4)
- primary bone marrow problem
- secondary bone marrow problem
- ineffective myelopoiesis
- hypersplenism
what could cause this general pattern of the Differential? Total WBC HIGH Neuts HIGH Bands HIGH Lymphs Monos Eos Basophils Blasts
bacterial infection
what could cause this general pattern of the Differential? Total WBC LOW Neuts Bands Lymphs HIGH Monos Eos Basophils Blasts
viral infection
what could cause this general pattern of the Differential? Total WBC HIGH Neuts HIGH Bands Lymphs Monos Eos Basophils Blasts
steroids
what could cause this general pattern of the Differential? Total WBC HIGH Neuts Bands Lymphs Monos Eos Basophils Blasts
splenectomy
what could cause this general pattern of the Differential? Total WBC LOW Neuts Bands Lymphs Monos HIGH Eos Basophils Blasts
chemotherapy
what could cause this general pattern of the Differential? Total WBC VERY HIGH Neuts Bands Lymphs Monos Eos Basophils Blasts VERY HIGH
acute leukemia
What is aplastic anemia? it is a problem with what kinds of cells?
diminished/absent hematopoietic precursors in bone marrow. usually due to damage to the pluripotent stem cell.
Tear drop cells suggest what process? (general category and specific cause)
something infiltrating the bone marrow. Leukoerythroblastic reaction. specific: could be myelofibrosis
