78 Lymphocytosis and Lymphocytopenia Flashcards
Lymphocytosis is defined as an absolute lymphocyte count exceeding
4 × 10 9 /L
TRUE OR FALSE
The normal absolute lymphocyte count is significantly higher in childhood
TRUE
The normal absolute lymphocyte count is significantly higher in childhood
Blood film association
Reactive lymphocytes:
Large granular lymphocytes:
Smudge cells:
Blasts:
Blood film association
Reactive lymphocytes: infectious mononucleosis
Large granular lymphocytes: large granular lymphocytic leukemia
Smudge cells: chronic lymphocytic leukemia
Blasts: acute lymphocytic leukemia
Patients with ______________________ leukemia may have only transient lymphocytosis that is induced by stress or exercise.
Large granular lymphocytic leukemia
A syndrome in patients who have expanded populations of monoclonal B cells without other associated clinical signs or symptoms
Monoclonal B-Cell Lymphocytosis
Defined as the expansion of a monoclonal population of B cells with an absolute B-cell count of less than 5.0 × 10 9 /L in the absence of organomegaly, lymphadenopathy, extramedullary involvement, and cytopenias
Monoclonal B-Cell Lymphocytosis
Absolute B cell count of Low-count MBL/ screening MBL
<0.5 × 10 9 /L
Absolute B cell count of High-count MBL/clinical MBL
≥0.5 × 10 9 /L
TRUE OR FALSE
Individuals with known high-count MBL should not be considered suitable for blood donation
TRUE
Individuals with known high-count MBL should not be considered suitable for blood donation, and whether this applies to low-count MBL is a matter of investigation.
Both has risk for infection and not eligible for stem-cell donation
TRUE OR FALSE
Low-count MBL require routine followup by a hematologist because of the progression of low-count MBL to high-count MBL and CLL.
FALSE
Low-count MBL does not require routine followup by a hematologist because the progression of low-count MBL to high-count MBL and CLL is negligibe
TRUE OR FALSE
High-count MBL is biologically indistinguishable from CLL. High-count MBL is characterized by having a higher risk of infection, development of nonhematologic cancer, and progression to CLL compared with low-count MBL.
TRUE
High-count MBL is biologically indistinguishable from CLL. High-count MBL is characterized by having a higher risk of infection, development of nonhematologic cancer, and progression to CLL compared with low-count MBL.
The risk of progression requiring CLL-specific treatment among individuals with high-count MBL
1%–2% per year
Patients with high-count MBL are at an increased risk of developing a nonhematologic cancer (breast, lung, and gastrointestinal tract) by a factor of
2
Individuals with high-count MBL should be followed with a physical examination and complete blood count with differential counts by a hematologist every _______ months, and monitored for progression to CLL
6–12 months
A chronic, moderate increase in absolute lymphocyte counts (>4 × 10 9 /L) without evidence for infection or other conditions that can increase the lymphocyte count
Persistent Polyclonal Lymphocytosis of B Lymphocytes
Mostly affects middle-aged women who often are human leukocyte antigen DR7–positive and is associated with smoking.
Persistent Polyclonal Lymphocytosis of B Lymphocytes
Characteristic of lymphocytes in Persistent Polyclonal Lymphocytosis
- CD27+ IgM+IgD+ B cells
- Binucleated lymphocytes
- Increased IgM serum levels
Specific morphologic features predictive of Persistent Polyclonal Lymphocytosis of B Lymphocytes
Basophilic vacuolated cytoplasm and monocytoid changes
Conditions associated with an increase in the absolute number of lymphocytes secondary to a physiologic or pathophysiologic response to infection, toxins, cytokines, or unknown factors.
SECONDARY (REACTIVE) LYMPHOCYTOSIS
The most common cause reactive lymphocytosis
Infectious Mononucleosis
In cases of mononucleosis secondary to infection with Epstein-Barr virus (EBV), the atypical lymphocytes commonly consist of polyclonal populations of
CD8+ T cells, γ/δ T cells, and CD16+CD56+ NK cells
A disorder that occurs in children usually between the ages of 2 and 10 years characterized by an increase in blood lymphocytes, often to 20–30 × 10 9 /L and occasionally as high as 100 × 10 9 /L
Acute infection lymphocytosis
- Lymph node enlargement and splenomegaly do not occur
- Patient’s serum usually is negative for heterophile antibodies
- Caused by cytomegalovirus, coxsackievirus B2
Characteristic of the lymphocytes in cases of pertussis
Lymphocytes have cleaved nuclei
Pathophysiology of lymphocytosis in pertussis
Lymphocytosis in pertussis is polyclonal with a normal T:B lymphocyte ratio and primarily results from failure of lymphocytes to leave the blood because of pertussis toxin
Result from expansions of NK cells, CD8+ T cells, or, more rarely, CD4+ T cells
Large granular lymphocytosis (LGL)
The lymphocytosis in LGL is secondary to ______________NK cells and is termed NK lymphocytosis
CD3–CD16+CD56+ NK cells
LGLL is a heterogeneous disorder characterized by an increase in the number of blood large granular lymphocytes between 2 and 20 × 10 9 /L for more than ____________ without a clearly identified cause
Six months
Most notable mutation in T-LGLL and NK-LGLL
STAT3 and STAT5B
STAT3 or STAT5B
Less common and are associated with a more aggressive disease.
STAT5B
LGLL and chronic NK lymphocytosis are considered indolent diseases with a median survival of ______years
9–10 years
Neutropenia and association with rheumatoid arthritis is more associated with ______ LGLL
T-LGLL
LGL has been observed in 20% of allogeneic hematopoietic cell transplant recipients for a variety of malignancies, with a median onset of _____ days from transplant
312 days
Patients with NK lymphocytosis frequently have recurrent cutaneous lesions, such as:
Livedoid vasculopathy, urticarial vasculitis, or complex recurrent aphthous stomatitis
Drugs associated with lymphocytosis when used for chronic myelogenous leukemia and CLL
Dasatinib and ibrutinib
TRUE OR FALSE
Some studies suggest that lymphocytosis after dasatinib is associated with a favorable response in chronic myelogenous leukemia.
TRUE
Some studies suggest that lymphocytosis after dasatinib is associated with a favorable response in chronic myelogenous leukemia.
TRUE OR FALSE
The prolonged lymphocytosis in CLL taking Ibrutinib likely represents a persistent quiescent clone and is not associated with a risk of relapse
TRUE
The prolonged lymphocytosis in CLL taking Ibrutinib likely represents a persistent quiescent clone and is not associated with a risk of relapse
This resolves within 8 months in most patient
Two phases of stress lymphocytosis after catecholamine administration:
A quick (<30 min) mobilization of lymphocytes, followed by an increase in granulocyte numbers with decreasing lymphocyte numbers
Delayed hypersensitivity reactions to insect bites, especially__________, may be associated with a large granular lymphocytic lymphocytosis and adenopathy.
Mosquitos
Neoplastic disease that may have a polyclonal T-cell lymphocytosis thought to be secondary to the aberrant release of hormones by the neoplastic epithelium.
Malignant thymoma
Lymphocytopenia is defined as a total lymphocyte count less than
1.0 × 10 9 /L
But some consider the lower limit of normal to be 1.5 × 10 9 /L
Approximately 80% of normal adult blood lymphocytes are ______lymphocytes and nearly two-thirds of blood T lymphocytes are ____________T lymphocytes
T lymphocytes
CD4+ (helper) T lymphocytes
Average absolute number of T lymphocytes in normal adult blood
1.9 × 10 9 /L
ranging from 1.0–2.3 × 10 9 /L
Average absolute number of CD4+ T lymphocytes
1.1 × 10 9 /L
ranging from 7.2–14 × 10 8 /L
Average absolute number of CD8+ T lymphocytes
6.5 × 10 8 /L
ranging from 3.8–9.7 × 10 8 /L
Condition with associated lymphopenia because of premature destruction of T cells secondary to a defect in the lymphocyte cytoskeleton
Wiskott-Aldrich syndrome
Ethnic groups that have lower CD4+ T-cell counts in the absence of other identified factors
Ethiopians and Chukotka natives
The most common infectious disease associated with lymphopenia
AIDS caused by HIV
Destruction and/or clearance of CD4+ T cells infected with HIV-1 or HIV-2
TRUE OR FALSE
Lymphopenia is considered a surrogate marker for sepsis-induced immunosuppression and identifies a subpopulation of patients at a higher risk of death
TRUE
Lymphopenia is considered a surrogate marker for sepsis-induced immunosuppression and identifies a subpopulation of patients at a higher risk of death
Presence of_________ antibodies was independently associated with disease activity and lupus nephritis
Antilymphocyte antibodies
TRUE OR FALSE
Lymphocytopenia remains a strong predictor of all-cause or cardiovascular mortality
TRUE
Lymphocytopenia remains a strong predictor of all-cause or cardiovascular mortality
Deficiency of this mineral leads to a significant decrease in the development of B cells in the bone marrow.
Zinc
Defined by the WHO as a CD4+ T-lymphocyte count less than 0.3 × 10 9 /L on two separate occasions in patients without serologic or virologic evidence of HIV-1 or HIV-2 infection or any other cause of immunodeficiency.
Idiopathic CD4+ T lymphocytopenia (ICL)
Unlike in HIV infection, the decrease in the CD4 cell counts of patients with ICL is generally slow.
A mutation in the ______ gene led to an immunodeficiency syndrome manifesting as an absence of B cells, agammaglobulinemia, and infections highlighting the importance of zinc in B-cell development
ZIP7 gene
