Hemopath 2 WBC Flashcards
(15 cards)
What is the normal range for total white blood cell (WBC) count, and what do deviations suggest?
Normal range: 4,000–11,000 cells/μL
Leukocytosis suggests infection, inflammation, or leukemia.
Leukopenia may reflect bone marrow suppression, viral infection, or autoimmune destruction.
What is the Absolute Neutrophil Count (ANC), and how is it clinically stratified?
ANC = WBC × (% neutrophils + % bands)
> 1,500/μL: Normal
1,000–1,500/μL: Mild neutropenia
<500/μL: Severe neutropenia — high risk of serious infection.
What roles do neutrophils play in the immune response, and what stimulates their production?
Neutrophils are first-line phagocytes against bacteria. Their production increases with bacterial infection, stress, corticosteroids, and inflammation (via G-CSF and IL-1).
What does a “left shift” in neutrophils mean, and when is it observed?
A left shift indicates an increase in immature neutrophils (e.g., bands, metamyelocytes). Seen in infections, inflammation, or marrow stimulation.
What do toxic granulations, Döhle bodies, and cytoplasmic vacuoles in neutrophils suggest?
Markers of toxic change — commonly seen in severe bacterial infections and sepsis.
What are common non-infectious causes of neutropenia?
Chemotherapy or radiation.
Aplastic anemia.
Drug-induced (e.g., clozapine, methimazole).
Autoimmune destruction.
What causes eosinophilia, and what do eosinophils release?
Eosinophilia is seen in parasitic infections, allergic disorders (e.g., asthma), and some cancers. Eosinophils release major basic protein, which is toxic to parasites and contributes to tissue damage.
When are basophils elevated, and what mediators do they release?
Basophilia occurs in chronic myeloid leukemia (CML) and allergic reactions. Basophils release histamine, leukotrienes, and cytokines.
What are the primary roles of monocytes, and how do they function in tissues?
Monocytes enter tissues and differentiate into macrophages or dendritic cells. They phagocytose pathogens and present antigens to T cells (APCs).
What causes lymphocytosis, and how does the age or cause affect its significance?
Lymphocytosis is seen in viral infections (e.g., EBV, CMV) and in CLL in older adults. It may be reactive or neoplastic depending on the context and morphology.
What are atypical lymphocytes, and in what condition are they typically seen?
Large, irregular lymphocytes with abundant basophilic cytoplasm — characteristic of infectious mononucleosis due to EBV.
How can you differentiate between reactive lymphocytosis and leukemia?
Reactive: Polymorphic lymphocytes, transient, linked to infection.
Leukemia (e.g., CLL): Monoclonal, persistent, with smudge cells and possibly cytopenias.
What is lymphopenia, and what are common causes?
Lymphopenia = decreased lymphocyte count. Caused by HIV/AIDS, corticosteroid therapy, chemotherapy, or immunodeficiencies.
What is chronic lymphocytic leukemia (CLL), and how does it present?
CLL involves clonal proliferation of mature B cells. Presents with persistent lymphocytosis, smudge cells, hypogammaglobulinemia, and sometimes lymphadenopathy.
What is a smudge cell, and why is it seen in CLL?
A smudge cell is a ruptured, fragile lymphocyte seen on a smear. Characteristic of CLL due to the fragility of the neoplastic lymphocytes.
