MASTOCYTOSIS Flashcards
What is the most common form of mastocytosis in children?
A. Indolent systemic mastocytosis (ISM)
B. Aggressive systemic mastocytosis (ASM)
C. Mast cell leukemia (MCL)
D. Cutaneous mastocytosis (CM)
D. Cutaneous mastocytosis (CM)
- Cutaneous mastocytosis is the most common diagnosis in children and indicates disease limited to skin with absence of pathologic infiltrates in internal organs.
Which of the following is a characteristic finding in systemic mastocytosis (SM)?
A. Bone marrow biopsy showing >30% infiltration of mast cells
B. Cutaneous lesions without internal organ involvement
C. Absence of somatic KIT mutations
D. Peripheral blood circulating atypical mast cells
A. Bone marrow biopsy showing >30% infiltration of mast cells
What is the hallmark skin lesion associated with cutaneous mastocytosis?
A. Reddish-brown macules, papules, or plaques that respond to trauma with urtication and erythema
B. Vesicular lesions that evolve into bullae
C. Generalized erythematous rash without itching
D. Solitary nodules with no systemic symptoms
A. Reddish-brown macules, papules, or plaques that respond to trauma with urtication and erythema
Which variant of systemic mastocytosis is associated with the poorest prognosis?
A. Indolent systemic mastocytosis (ISM)
B. Aggressive systemic mastocytosis (ASM)
C. Mast cell leukemia (MCL)
D. Smoldering systemic mastocytosis (SSM)
C. Mast cell leukemia (MCL)
What clinical sign is associated with Darier’s sign in mastocytosis?
A. Skin lesions that develop bullae when scratched
B. Erythema and urtication following trauma to a lesion
C. Spontaneous ulceration of skin lesions
D. Hyperpigmentation of lesions after irritation
B. Erythema and urtication following trauma to a lesion
Which of the following is the recommended first-line therapy for flushing and pruritus in mastocytosis?
A. Proton pump inhibitors
B. H1 antihistamines
C. Oral cromolyn sodium
D. Systemic glucocorticoids
B. H1 antihistamines
- H1 antihistamine for flushing and pruritus
- H2 antihistamine or proton pump inhibitor for gastric acid hypersecretion
- oral cromolyn sodium for diarrhea and abdominal pain
What is a typical use of systemic glucocorticoids in the management of systemic mastocytosis?
A. To treat anaphylaxis
B. To manage severe flushing
C. To alleviate malabsorption
D. To reduce gastric acid secretion
C. To alleviate malabsorption
Which of the following medications is used as mast cell cytoreductive therapy for advanced systemic mastocytosis?
A. H1 antihistamines
B. Cromolyn sodium
C. Midostaurin
D. Omeprazole
C. Midostaurin
- Mast cell cytoreductive therapy consisting of midostaurin, avapritinib, IFN-α, or cladribine is generally reserved for advanced, nonindolent variants of SM
What noninvasive test can be used as an initial diagnostic step in suspected systemic mastocytosis?
A. Serum total tryptase level
B. Skin biopsy
C. Peripheral blood smear
D. Serum immunoglobulin E (IgE)
A. Serum total tryptase level
Why is a self-injectable epinephrine prescription recommended for most patients with systemic mastocytosis?
A. To alleviate severe flushing episodes
B. To manage episodes of vascular collapse
C. Due to an increased incidence of anaphylaxis
D. To reduce diarrhea and abdominal pain
C. Due to an increased incidence of anaphylaxis
TRUE OR FALSE: Most forms of the disease are characterized by somatic gain-of-function mutations in the stem cell factor receptor (KIT) gene
TRUE
Systemic mastocytosis (SM) refers to involvement of what noncutaneous site
A. Skin
B. Bone marrow
C. Liver
D. Lung
B. Bone marrow
- Systemic mastocytosis (SM) refers to involvement of a noncutaneous site (usually bone marrow).
Which of the following features is characteristic of indolent systemic mastocytosis (ISM)?
A) Presence of an associated hematologic disorder
B) Bone marrow infiltration >30%
C) Organ dysfunction due to mast cell infiltration
D) Normal life expectancy
Correct Answer: D) Normal life expectancy
Rationale: ISM is the most common form of systemic mastocytosis and is characterized by the absence of organ dysfunction (C findings), hematologic disorders, or mast cell leukemia. Patients with ISM have a normal life expectancy, distinguishing it from more aggressive forms of the disease.
Which laboratory finding is most consistent with a diagnosis of smoldering systemic mastocytosis (SSM)?
A) Baseline serum tryptase >200 ng/mL
B) Circulating mast cells in peripheral blood
C) Normal mast cell burden in the bone marrow
D) Organ damage due to mast cell infiltration
Correct Answer: A) Baseline serum tryptase >200 ng/mL
Rationale: SSM is characterized by a high mast cell burden, which includes bone marrow infiltration >30% and a baseline serum tryptase level >200 ng/mL. Unlike aggressive systemic mastocytosis (ASM) and mast cell leukemia (MCL), SSM does not cause organ damage (C findings).
Which of the following differentiates aggressive systemic mastocytosis (ASM) from smoldering systemic mastocytosis (SSM)?
A) Presence of B findings
B) Elevated serum tryptase
C) Presence of C findings
D) Involvement of the bone marrow
Correct Answer: C) Presence of C findings
Rationale: ASM is characterized by mast cell infiltration leading to organ dysfunction, which is defined as C findings (e.g., cytopenias, liver dysfunction, malabsorption). SSM, in contrast, has B findings (high mast cell burden) but lacks C findings.
Which of the following is the rarest and most fatal form of systemic mastocytosis?
A) Indolent systemic mastocytosis (ISM)
B) Smoldering systemic mastocytosis (SSM)
C) Aggressive systemic mastocytosis (ASM)
D) Mast cell leukemia (MCL)
Correct Answer: D) Mast cell leukemia (MCL)
Rationale: MCL is the least common and most aggressive form of systemic mastocytosis. It is associated with circulating atypical mast cells in the peripheral blood and is invariably fatal.
Which of the following is a major diagnostic criterion for systemic mastocytosis?
A) Bone marrow mast cell infiltration of >30%
B) Serum tryptase level >200 ng/mL
C) Multifocal, dense mast cell aggregates in the bone marrow
D) Presence of an associated hematologic disorder
Correct Answer: C) Multifocal, dense mast cell aggregates in the bone marrow
Rationale: A major diagnostic criterion for systemic mastocytosis is the presence of multifocal, dense mast cell aggregates in the bone marrow or other extracutaneous tissues. Other diagnostic criteria include elevated tryptase and mast cell clonality markers.
A patient presents with systemic mastocytosis and hepatosplenomegaly, cytopenia, and weight loss. Which subtype is most likely?
A) Indolent systemic mastocytosis (ISM)
B) Smoldering systemic mastocytosis (SSM)
C) Aggressive systemic mastocytosis (ASM)
D) Mast cell leukemia (MCL)
Correct Answer: C) Aggressive systemic mastocytosis (ASM)
Rationale: ASM is characterized by the presence of C findings, which indicate organ dysfunction due to mast cell infiltration. Hepatosplenomegaly, cytopenia, and weight loss are signs of organ involvement, making ASM the most likely diagnosis.
Which of the following is a diagnostic criterion (C finding) for aggressive systemic mastocytosis (ASM)?
A) Osteoporosis without osteolytic lesions
B) Hepatomegaly with normal liver function
C) Palpable splenomegaly with hypersplenism
D) Mild anemia with hemoglobin of 11 g/dL
Correct Answer: C) Palpable splenomegaly with hypersplenism
Rationale: Palpable splenomegaly with associated hypersplenism is one of the required C findings for an ASM diagnosis. Osteoporosis alone and hepatomegaly without impaired liver function do not fulfill the criteria. Mild anemia (Hb >10 g/dL) does not qualify as cytopenia in ASM.
Which hematologic abnormality qualifies as a C finding in aggressive systemic mastocytosis?
A) Hemoglobin of 11.5 g/dL
B) Platelet count of 150,000/μL
C) Absolute neutrophil count (ANC) of 900/μL
D) White blood cell count of 4,500/μL
Correct Answer: C) Absolute neutrophil count (ANC) of 900/μL
Rationale: Cytopenias are considered C findings in ASM when ANC is <1000/μL, hemoglobin is <10 g/dL, or platelets are <100,000/μL. ANC of 900/μL qualifies, whereas the other values listed do not meet the threshold.
A patient with systemic mastocytosis presents with hepatomegaly, ascites, and abnormal liver function tests. What does this indicate?
A) Normal progression of indolent systemic mastocytosis
B) Presence of a B finding
C) A C finding suggestive of aggressive systemic mastocytosis
D) Mast cell leukemia
Correct Answer: C) A C finding suggestive of aggressive systemic mastocytosis
Rationale: Hepatomegaly with ascites and impaired liver function is a C finding, which supports a diagnosis of ASM rather than indolent systemic mastocytosis (ISM) or smoldering systemic mastocytosis (SSM).
