Pediatric WBC disorders - Newman

Question 1

how do you calculate absolute neutrophil count (ANC)?

Answer 1

(% neutrophils + % bands) x WBC / 100

Question 2

decrease in the absolute neutrophil count (ANC) to <1500

Answer 2

neutropenia

Question 3

neutropenia is considered severe if ANC less that what?

Answer 3

500

- risk of serious infection is high!

Question 4

neutropenia is considered moderate if ANC is what?

Answer 4

500-1000

Question 5

neutropenia is considered mild if ANC is what?

Answer 5

1000-1500

Question 6

life-threatening pyogenic infections, often in infancy

• impaired myeloid differentiation caused by maturational arrest of neutrophil precursors
• AR inheritance

Answer 6

severe congenital neutropenia

- aka Kostmann syndrome

Question 7

cyclic fever, oral ulcers, gingivitis, periodontal disease, recurrent bacterial infections

• stem cell regulatory defect resulting in defective maturation
• sporadic, or AD inheritance

Answer 7

cyclin neutropenia

Question 8

triad of neutropenia, exocrine pancreas insufficiency, skeletal abnormalities (metaphyseal dysplasia, thoracic/rib abnormalities, shortened limbs)

• may have defects in neutrophil mobility, migration, and chemotaxis in addition to neutropenia
• AR inheritance

Answer 8

schwachman-diamond syndrome

- **increased risk of myelodysplastic syndrome or leukemia

Question 9

bone marrow failure syndrome, all cell lines affected

• GU and skeletal abnormalities
• increased xsome fragility
• AR, presents in first 10 years of life
• “classic example” of pancytopenia/bone marrow failure/aplastic anemia
• risk of AML, brain tumors, Wilms tumor

Answer 9

fanconi anemia

Question 10

delayed separation of umbilical cord (>3weeks), recurrent and severe bacterial and fungal infections without pus accumulation

• neutrophils have diminished adhesion to surfaces
• rare, AR inheritance

Answer 10

leukocyte adhesion deficiency

Question 11

triad of:

• severe eczema
• recurrent bacterial infections of skin (staph)
• recurrent pulmonary infections (bacterial, fungi)
• sporadic, AD, less commonly AR inheritance

Answer 11

hyper-IgE syndrome

- aka Job syndrome

Question 12

partial oculocutaneous albinism, peripheral and cranial neuropathies, neutropenia, recurrent pyogenic infections

• defects in granule morphogenesis, chemotaxis, and degranulation, ineffective granulopoiesis (shows giant granulocytes on smear)
• AR inheritance

Answer 12

Chediak-Higashi syndrome

Question 13

recurrent purulent infections with fungal or bacterial catalase-positive organisms, usually starting in infancy

• chronic inflammatory granulomas
• defect in oxidative metabolism, absent generation of superoxide
• 1 in 250k
• x-link recessive
• GOOD prognosis with aggressive tx

Answer 13

chronic granulomatous disease

Question 14

many viruses cause neutropenia within first 2-3 days of illness, lasting up to 1 week

• decreased bone marrow production
• depleted marrow reserves
• increased neutrophil margination with decreased circulating neutrophils

Answer 14

infection-associated neutropenia

Question 15

what are the MC viruses causing neutropenia?

Answer 15

• parvovirus B19 (slapped-cheek appearance!)

- HIV

Question 16

what nutritional deficiency can cause neutropenia?

Answer 16

vit B12

Question 17

usually a reactive process to infection which subsides with resolution of the acute event

• chronic inflammation (auto-immune)
• oncologic (if WBC>100 suspect marrow infiltration)
• seizure

Answer 17

leukocytosis