An 8-year-old boy has had fever, mouth ulcers and sore gums about every 3 weeks since infancy, recovering fully in between. He has no lymphadenopathy or splenomegaly and takes no medicines. Absolute neutrophil counts taken twice a week for 6 weeks (reference 1.5-8.0 × 10^9/L) are: day 1, 2.6; day 4, 1.1; day 8, 0.1; day 11, 0.2; day 15, 1.8; day 18, 3.4; day 22, 2.1; day 25, 0.6; day 29, 0.05; day 32, 0.3; day 36, 2.2; day 39, 3.0. The monocyte count rises at each low point. Hemoglobin and platelets are normal, the film shows no blasts, and antineutrophil antibodies are negative. The most likely diagnosis is:

Autoimmune neutropenia of childhood

Benign ethnic (Duffy-null) neutropenia

Toxic granulation in the neutrophils of a patient with sepsis consists of:

Primary granules that keep their dark staining

Phagocytosed bacteria in the cytoplasm

Patches of rough endoplasmic reticulum

Fused primary granules forming rods

A 24-year-old man has fever, a rash, mouth ulcers and swollen nodes 3 weeks after unprotected sex. WBC 9.8 × 10^9/L with 55% lymphocytes, many of them reactive. Heterophile test negative; EBV VCA IgG and EBNA positive, VCA IgM negative; CMV IgM negative. Which test should be done next?

HIV-1/2 antigen/antibody combination test

Flow cytometry for a clonal B-cell population

Bone marrow aspirate and trephine biopsy

Repeat heterophile test in one week

A healthy term baby has a CBC on the first day of life: WBC 24 × 10^9/L, neutrophils 62% with a few metamyelocytes, no toxic changes, and 5 nucleated red cells per 100 WBC (day-1 reference: WBC 9 to 30 × 10^9/L; up to 10 nucleated red cells per 100 WBC). How is this best interpreted?

Neonatal sepsis with a left shift

Transient abnormal myelopoiesis

A leukoerythroblastic marrow infiltration

Reactive white cell changes and benign disorders

14 DOH Abu Dhabi (HAAD) lab licensing practice questions on Reactive white cell changes and benign disorders, part of Hematology. The first 14 are below; the first 5 with answers and explanations (tap Show answer after you have chosen), the rest in Learn with a free account.

Question 1 · Hard
An 8-year-old boy has had fever, mouth ulcers and sore gums about every 3 weeks since infancy, recovering fully in between. He has no lymphadenopathy or splenomegaly and takes no medicines. Absolute neutrophil counts taken twice a week for 6 weeks (reference 1.5-8.0 × 10^9/L) are: day 1, 2.6; day 4, 1.1; day 8, 0.1; day 11, 0.2; day 15, 1.8; day 18, 3.4; day 22, 2.1; day 25, 0.6; day 29, 0.05; day 32, 0.3; day 36, 2.2; day 39, 3.0. The monocyte count rises at each low point. Hemoglobin and platelets are normal, the film shows no blasts, and antineutrophil antibodies are negative. The most likely diagnosis is:
1. AAutoimmune neutropenia of childhood
2. BBenign ethnic (Duffy-null) neutropenia
3. CSevere congenital neutropenia
4. DCyclic neutropenia
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Answer: D · Cyclic neutropenia
The neutrophil count falls below 0.2 × 10^9/L about every 21 days (lows on days 8 and 29) and returns to normal in between, and his symptoms recur on the same cycle, which defines cyclic neutropenia. It is usually caused by a mutation in ELANE, the neutrophil elastase gene, and the monocyte count typically rises as the neutrophils fall. The diagnosis needs counts two or three times a week for about 6 weeks, because a single count can be normal or very low by chance. Severe congenital neutropenia keeps the count very low all the time, and autoimmune neutropenia has antineutrophil antibodies and no regular cycle. Benign ethnic (Duffy-null-associated) neutropenia gives a stable, mildly low count without infections.
- A: Antineutrophil antibodies are negative, and autoimmune neutropenia has no regular cycle.
- B: Duffy-null-associated neutropenia is mild and stable and does not fall near zero.
- C: Severe congenital neutropenia keeps the count low all the time; here it recovers to normal.
Question 2 · Easy
Toxic granulation in the neutrophils of a patient with sepsis consists of:
1. APhagocytosed bacteria in the cytoplasm
2. BPatches of rough endoplasmic reticulum
3. CPrimary granules that keep their dark staining
4. DFused primary granules forming rods
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Answer: C · Primary granules that keep their dark staining
In severe infection, neutrophil production is speeded up and cells leave the marrow early. Their primary (azurophilic) granules keep the dark, purple-black staining that is normally lost as the cells mature, so the cytoplasm looks coarsely granular. Toxic granulation is also seen after G-CSF therapy and in pregnancy. A stain that is too alkaline can mimic it, so compare with other films stained in the same run.
- A: Ingested bacteria are larger, uniform rods or cocci, often inside vacuoles.
- B: Patches of rough endoplasmic reticulum are Döhle bodies.
- D: Fused primary granules forming rods are Auer rods, seen in myeloid blasts.
Question 3 · Hard
A 24-year-old man has fever, a rash, mouth ulcers and swollen nodes 3 weeks after unprotected sex. WBC 9.8 × 10^9/L with 55% lymphocytes, many of them reactive. Heterophile test negative; EBV VCA IgG and EBNA positive, VCA IgM negative; CMV IgM negative. Which test should be done next?
1. AFlow cytometry for a clonal B-cell population
2. BHIV-1/2 antigen/antibody combination test
3. CBone marrow aspirate and trephine biopsy
4. DRepeat heterophile test in one week
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Answer: B · HIV-1/2 antigen/antibody combination test
The EBV results show past infection and CMV IgM is negative, so another cause of the reactive lymphocytosis is needed. Acute HIV infection causes a mononucleosis-like illness with rash and mouth ulcers 2 to 4 weeks after exposure. A fourth-generation antigen/antibody test detects p24 antigen before antibodies appear, and HIV RNA testing can confirm very early infection. Reactive lymphocytes of mixed size and shape point to a viral cause rather than a neoplasm.
- A: Varied reactive lymphocytes suggest infection, not a clonal disorder.
- C: Marrow examination is not needed for a reactive lymphocytosis with a clear infectious lead.
- D: EBNA and VCA IgG without VCA IgM show past EBV infection, so repeating the heterophile test will not help.
Question 4 · Medium
A healthy term baby has a CBC on the first day of life: WBC 24 × 10^9/L, neutrophils 62% with a few metamyelocytes, no toxic changes, and 5 nucleated red cells per 100 WBC (day-1 reference: WBC 9 to 30 × 10^9/L; up to 10 nucleated red cells per 100 WBC). How is this best interpreted?
1. ANeonatal sepsis with a left shift
2. BNormal for a newborn on day 1
3. CTransient abnormal myelopoiesis
4. DA leukoerythroblastic marrow infiltration
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Answer: B · Normal for a newborn on day 1
At birth the WBC is normally high, with a neutrophil majority, a few immature granulocytes and some nucleated red cells. Birth stress and high erythropoietin levels drive these changes, which settle over the first week. Within a few weeks lymphocytes become the main white cell and stay so through early childhood. Age-specific reference intervals prevent normal newborn counts from being reported as abnormal.
- A: Without toxic changes or other signs of infection, sepsis is not suggested.
- C: Transient abnormal myelopoiesis shows circulating blasts, usually in babies with Down syndrome.
- D: Infiltration gives a leukoerythroblastic picture in a sick patient, not in a healthy newborn.
Question 5 · Easy
Lymphocytes changed by a viral infection should be reported, as recommended by ICSH, as:
1. ALarge granular lymphocytes
2. BReactive lymphocytes
3. CAbnormal lymphocytes
4. DAtypical lymphocytes
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Answer: B · Reactive lymphocytes
The International Council for Standardization in Haematology (ICSH) recommends the term 'reactive lymphocytes' for cells with a benign, antigen-driven cause, such as infectious mononucleosis. Cells suspected of being neoplastic are reported as 'abnormal lymphocytes'. The older term 'atypical lymphocyte' is discouraged because it does not say which of the two is meant. Reactive lymphocytes are large, with plentiful blue cytoplasm and a range of sizes and shapes.
- A: Large granular lymphocytes are a normal subset of NK and cytotoxic T cells, not the term for viral changes.
- C: 'Abnormal lymphocytes' is reserved for cells suspected to be neoplastic.
- D: 'Atypical' is ambiguous and is no longer recommended by ICSH.
Question 6 · Easy
Two days after starting high-dose prednisolone, a patient's white cell differential typically shows:
1. ANeutrophilia with lymphopenia and eosinopenia
2. BLymphocytosis with reactive lymphocytes
3. CEosinophilia with a mild monocytosis
4. DNeutropenia with a relative lymphocytosis
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Question 7 · Easy
A persistent absolute monocytosis is most typical of which infection?
1. APertussis
2. BTuberculosis
3. CHookworm infection
4. DStreptococcal pharyngitis
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Question 8 · Medium
When molecular testing is not yet available, which result best separates a neutrophilic leukemoid reaction from chronic myeloid leukemia?
1. AMyelocytes and metamyelocytes in the blood
2. BA left shift to band forms
3. CA WBC above 50 × 10^9/L
4. DA raised LAP score
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Question 9 · Hard
A 38-year-old man who grew up in rural South Asia and now lives in Abu Dhabi is to start high-dose corticosteroids. His eosinophil count is 2.6 × 10^9/L (reference below 0.5 × 10^9/L). Which infection must be excluded first?
1. AStrongyloides stercoralis
2. BEnterobius vermicularis
3. CAscaris lumbricoides
4. DGiardia duodenalis
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Question 10 · Medium
A woman taking carbimazole for Graves disease has fever and a sore throat. Results: hemoglobin 128 g/L (12.8 g/dL), platelets 245 × 10^9/L, WBC 1.4 × 10^9/L, absolute neutrophil count 0.05 × 10^9/L. The most likely diagnosis is:
1. ABenign ethnic neutropenia
2. BAplastic anemia
3. CDrug-induced agranulocytosis
4. DCyclic neutropenia
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Question 11 · Hard
On a blood film from a febrile ICU patient, several neutrophils contain small, uniform, dark-blue rods inside cytoplasmic vacuoles. No stain deposit is seen elsewhere on the slide. What should the technologist do?
1. ARecord the inclusions as Döhle bodies
2. BNotify the clinician urgently as a critical finding
3. CRestain the slide because these are stain deposit
4. DReport the cells only as showing toxic granulation
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Question 12 · Easy
Marked eosinophilia is most often associated with which conditions?
1. ALong-term corticosteroid treatment
2. BBacterial sepsis and septic shock
3. CAcute viral infections such as influenza
4. DHelminth infections and allergies
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Question 13 · Medium
A young adult has many large reactive lymphocytes with abundant cytoplasm that scallops around neighboring red cells, and a positive heterophile antibody test. What is the diagnosis?
1. AAcute lymphoblastic leukemia
2. BChronic lymphocytic leukemia
3. CInfectious mononucleosis (EBV)
4. DChronic myeloid leukemia
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Question 14 · Medium
Below which absolute neutrophil count is an adult usually considered neutropenic?
1. A1.5 × 10^9/L
2. B10.0 × 10^9/L
3. C0.5 × 10^9/L
4. D4.0 × 10^9/L
Answer and explanation in LearnFree account

Reactive white cell changes and benign disorders

Toxic granulation in the neutrophils of a patient with sepsis consists of:

A 24-year-old man has fever, a rash, mouth ulcers and swollen nodes 3 weeks after unprotected sex. WBC 9.8 × 10^9/L with 55% lymphocytes, many of them reactive. Heterophile test negative; EBV VCA IgG and EBNA positive, VCA IgM negative; CMV IgM negative. Which test should be done next?

A healthy term baby has a CBC on the first day of life: WBC 24 × 10^9/L, neutrophils 62% with a few metamyelocytes, no toxic changes, and 5 nucleated red cells per 100 WBC (day-1 reference: WBC 9 to 30 × 10^9/L; up to 10 nucleated red cells per 100 WBC). How is this best interpreted?

Lymphocytes changed by a viral infection should be reported, as recommended by ICSH, as:

Two days after starting high-dose prednisolone, a patient's white cell differential typically shows:

A persistent absolute monocytosis is most typical of which infection?

When molecular testing is not yet available, which result best separates a neutrophilic leukemoid reaction from chronic myeloid leukemia?

A 38-year-old man who grew up in rural South Asia and now lives in Abu Dhabi is to start high-dose corticosteroids. His eosinophil count is 2.6 × 10^9/L (reference below 0.5 × 10^9/L). Which infection must be excluded first?

A woman taking carbimazole for Graves disease has fever and a sore throat. Results: hemoglobin 128 g/L (12.8 g/dL), platelets 245 × 10^9/L, WBC 1.4 × 10^9/L, absolute neutrophil count 0.05 × 10^9/L. The most likely diagnosis is:

On a blood film from a febrile ICU patient, several neutrophils contain small, uniform, dark-blue rods inside cytoplasmic vacuoles. No stain deposit is seen elsewhere on the slide. What should the technologist do?

Marked eosinophilia is most often associated with which conditions?

A young adult has many large reactive lymphocytes with abundant cytoplasm that scallops around neighboring red cells, and a positive heterophile antibody test. What is the diagnosis?

Below which absolute neutrophil count is an adult usually considered neutropenic?