Lecture 9 - Pediatric Cases Flashcards

1
Q

When does the physiologic nadir (low) for Hb occur in infants?*

A

At approximately 2 months of age

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What effect does anemia have on the Hb O2 dissociation curve?

A

Concentration of 2,3-DPG increases within the RBC —> oxygen dissociation curve shifts to the right —> affinity of Hb for oxygen is reduced in tissues needing to be oxygenated
Anemia also results in increased CO (HR goes up and flow murmur may be heard)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What are the pertinent components of a history to obtain when evaluating a person with suspected anemia?

A

Hx: race and ethnicity, diet, meds, chronic illness, recent infections, travel, exposure to sick contacts
FHx looking for anemia, splenomegaly, jaundice, early stage onset of gallstone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the signs and sx often seen in pts with anemia?

A

Sleepiness, irritability, decreased exercise tolerance, pale appearance, blood stool/urine, LAD, fever, viral sx, pain, menses (flow/length), SOB cough

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

The slower the anemia develops the better the body can what?

A

Compensate

Rapidly developing anemia usually results in more dramatic sx

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Look at

A

Anemia flow chart

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Anemia is the result of one or more of the following

A
Decreased RBC production (in bone marrow) 
Increased RBC destruction (hemolysis)
Blood loss (acute or chronic)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe intravascular hemolysis

A

Results in anemia, hemoglobinuria, hemoglobinemia, hemosiderinuria, jaundice
Mechanical, auto immune (complement fixation), intracellular parasites, toxins/drugs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe extravascular hemolysis

A

Results in anemia, jaundice, splenomegaly and sometimes hepatomegaly
Occurs in the reticuloendothelial system
Macrophages phagocytize RBCs as the result of abnormalities in RBC membrane/deformability

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

A low or low-normal number of reticulocytes in a pt with anemia is indicative of what?

A

An inadequate bone marrow response
Relative bone marrow failure
Ineffective erythropoiesis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

An increased number of reticulocytes is a normal bone marrow response to what?

A

Anemia (its trying to keep up, the problem is NOT with the bone marrow)
Ongoing RBC destruction (hemolysis), sequestration, blood loss

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is Diamond-Blackfan syndrome/anemia?

A

Congenital pure red cell aplasia that almost always presents in infancy
Increased apoptosis in erythroid precursors
Macrocytic with low/inadequate reticulocyte count

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is Fanconi anemia?*

A

Most common inherited form of aplastic anemia (bone marrow failure syndrome with all cell lines affected)
Macrocytic anemia with low/inadequate reticulocyte count
Leukopenia and thrombocytopenia are also present
GU and skeletal abnormalities
Due to genetic mutations; increased chromosome fragility
Increased apoptosis in the bone marrow
Progresses to pancytopenia
Autosomal recessive, May be up to 10 years old before it presents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Describe iron deficiency anemia

A

Commonly caused by a dietary deficiency of iron in pediatric patients
Common
Microcytic, hypochromic anemia with high RDW in infants and toddlers
Target cells on peripheral smears
Iron, ferritin and iron saturation are all low
Transferrin level is elevated
Pale child, big cow’s milk drink (suspect IDA)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the Mentzer index?

A

Useful in distinguishing IDA from beta thalassemia minor/trait in pediatric patients with mild microcytic anemia
MCV/RBC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What does a Mentzer index of >13 mean?

A

IDA is more likely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does a Mentzer index of <13 mean?

A

Thalassemia trait is more likely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What does a Mentzer index of =13 mean?

A

Indeterminate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

How do you calculate the absolute neutrophil count (ANC)?

A

((%neutrophils + %bands) x WBC) / 100
Mild neutropenia = 1000-1500
Moderate neutropenia = 500-100
Severe neutropenia = <500

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What class of drugs are most commonly associated with neutropenia?

A

Chemotherapeutics are most commonly associated with a lowered ANC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What is Kostmann syndrome?

A

Severe congenital neutropenia (ANC <200)
Autosomal recessive
Life threatening pyogenes infections early in life
Impaired myeloid differentiation caused by maturational arrest of neutrophil precursors
Increased risk of leukemia (AML)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is cyclic neutropenia?

A

Cyclic fever, oral ulcers, gingivitis, periodontal disease, recurrent bacterial infections
Stem cell regulatory defect resulting in defective maturation
ANC <200 for 3-7 days every 15-35 days
Autosomal dominant or sporadic
No increased risk of malignancy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is Schwachman-Diamond syndrome?

A

Triad of neutropenia, exocrine pancreas insufficiency, and skeletal abnormalities
Defects in neutrophil mobility, migration, and chemotaxis in addition to neutropenia
Autosomal recessive
Increased risk for myelodysplastic syndrome or leukemia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Children with fanconi anemia have an increased risk of developing what?

A

AML, brain tumors, Wilms tumor

25
Q

What is leukocyte adhesion deficiency?

A

Very rare
Results in delayed separation of umbilical cord stump (>3 weeks), recurrent and severe bacterial and fungal infections without pus formation, poor wound healing
Neutrophils have diminished adhesion to surfaces
Autosomal recessive
No known associated risk of malignancy

26
Q

What is hyper immunoglobulin E syndrome (Job syndrome)?

A

Triad of severe eczema, recurrent bacterial infections (usually staph) of skin, recurrent pulmonary infections (bacterial, fungal)
Defect in chemotaxis of neutrophils, increased IgE, eosinophilia
Very rare, sporadic, autosomal dominant
Increased risk of HL

27
Q

What is Chediak Higashi syndrome?

A

Partial oculocutaenous albinism, neuropathies, recurrent pyogenic infections
Defects in chemotaxis and degranulation, ineffective granulopoiesis
Very rare autosomal recessive
Usually fatal by 20 years of age
No known link to malignancy

28
Q

What is chronic granulomatous disease?

A

Recurrent purulent infections with fungal or bacterial catalase positive organisms
Usually starts in infancy
Chronic inflammatory granulomas
Defect in oxidative metabolism, absent generation of superoxide
Primarily X linked recessive
1:250,000
No known increased risk of malignancy

29
Q

Describe parvovirus B19 infections (Fifths disease)

A

Commonly seen viral illness with associated characteristics viral exanthem occurring 1-2 weeks after infection with the virus (bright red cheeks followed by a diffuse, lacy, erythematous rash)
Commonly results in anemia, can result in neutropenia/thrombocytopenia
Most adults have had this virus and are somewhat immune
Has been associated with spontaneous abortion in non immune women

30
Q

What immune deficiency is associated with DiGeorge syndrome?

A

Associated with absent thymus resulting in T cell immunodeficiency

31
Q

What is the #1 cause of death due to illness in the US among children?*

A

Brain cancer

Followed by leukemias

32
Q

What is the overall #1 cause of death in children?

A

Unintentional injuries (accidents)

33
Q

What is the most common malignancy between ages 15-19?

A

Hodgkin lymphoma

HHV-6, cytomegalovirus, and EBV have been implicated in the occurrence of HL

34
Q

What is the pathognomonic feature of HL?

A

Reed Sternberg cells (owl eyes)

35
Q

What are the B signs associated with HL?

A

Unexplained fever of 39C (102.2 F)
Weight loss >10% total body weight over 6 months
Drenching night sweats

36
Q

What are the indications for a CXR in a patient with LAD?

A

Any pt with persistent unexplained LAD unassociated with an obvious underlying inflammatory or infectious process should undergo a CXR to rule out a mediastinal mass (lymphoma loves the mediastinum)
Any pt with persistent LAD and accompanying respiratory sx (cough, SOB, chest pain) should have a CXR

37
Q

What is the most common type of lymphoma in children and adolescents?

A

Non Hodgkin lymphoma

38
Q

What is Wiscott-Aldrich syndrome?

A

X linked recessive
Classic triad of recurrent sino pulmonary and ear infections, severe atopic dermatitis, bleeding secondary to significant thrombocytopenia
Predisposes to development of lymphoma, especially B cell lymphoma (NHL)

39
Q

What are the 3 types of Burkitt lymphoma?

A

Sporadic
Endemic type
Immunodeficiency related

40
Q

Describe sporadic type Burkitt lymphoma

A

Abdominal disease, sometimes associated with EBV

Most often in Africa but can occur in other geographic places

41
Q

Describe endemic type Burkitt lymphoma

A

Head and neck disease, most often seen in Africa near the equator
Associated with EBV and malaria

42
Q

Describe immunodeficiency related Burkitt lymphoma

A

Associated with the use of immunosuppressive drugs

43
Q

What condition accounts for the greatest percentage of childhood malignancies?

A

Leukemias

Acute leukemias account for 97% of all childhood leukemias

44
Q

What genetic trisomy is associated with both AML and ALL?

A

Trisomy 21 (Down syndrome)

45
Q

Clinically significant bleeding is possible with a platelet count of what value?

A

<20 x 10^3/uL

46
Q

Life threatening hemorrhage is possible with a platelet count of what value?

A

<10 x 10^3/uL

47
Q

What is the most common cause of low platelets in kids?

A

ITP

48
Q

What clinical findings are consistent with thrombocytopenia?

A

Petechiae, purpura, gingival bleeding, epistaxis, menorrhagia, GI bleeding, hematuria, CNS hemorrhage, ecchymosis/bruises (excessive in unusual locations, easy bruising)

49
Q

Which conditions are associated with decreased platelet production?

A
Nutritional deficiencies (B12, folate, iron) 
Bone marrow failure or infiltration (aplastic anemia, leukemia, lymphoma) 
Genetic disorders (Wiscott Aldrich syndrome, Fanconi anemia, Schwachman Diamond syndrome, thrombocytopenia-absent radius syndrome (TAR)
50
Q

Which conditions are associated with increased platelet destruction/consumption?

A

ITP, HUS, TTP, Kasabach Merritt phenomena

51
Q

Describe immune thrombocytopenic purpura*

A

Fairly common (5/100,000 annually)
Kids usually feel okay
Anti platelet Abs
50% follows a viral infection by 1-3 weeks
Plt count usually <20,000 with other cell lines being normal
If other cell lines are affected must consider bone marrow aspirate (especially if steroid therapy is being considered)
PT/PTT normal
Tx: usually will self resolve with supportive care, prednisone is used when severe, may become chronic

52
Q

What is Kasabach-Merritt phenomenon?*

A

Thrombocytopenia and hypo-fibrinogenemia associated with giant hemangioma and associated intravascular coagulation
Rare

53
Q

What are red flag in pts with thrombocytopenia?

A

Any evidence of pancytopenia
Raised LDH (elevated in cancer)
Associated new renal impairment

54
Q

What is the criteria for diagnosing ITP?

A

Anti platelet Abs present
Normal RBCs, PT/INR, PTT, fibrinogen, fibrin monomers, fibrin degradation, D dimers
Therapy = steroids and IVIG

55
Q

Describe acute ITP

A

Peak incidence of 2-6 years
Antecedent infection common 1-3 weeks before
Abrupt onset of bleeding
Platelet count <20,000
Eosinophilia/lymphocytosis is common
Duration = 2-6 weeks, rarely longer
Spontaneous remission occurs in 80% of cases

56
Q

Describe chronic ITP

A
Peak age 20-40 years 
3:1 female:male 
Antecedent infection unusual 
Insidious onset of bleeding 
Platelet count 30-80,000 
Eosinophilia/lymphocytosis rare 
Duration = months or years 
Spontaneous remission uncommon
57
Q

Describe hemolytic uremic syndrome

A

Presents after acute gastroenteritis (within the last 2 weeks) as a classic triad of microangiopathic hemolytic anemia, thrombocytopenia, acute renal damage/failure
Most cases are caused by E. Coli O157:H7 (produces shiga toxin)
Prognosis depends on the amount of renal damage and blood in the urine will always be present (if protein is present prognosis is worse)

58
Q

What is the usual presentation and lab findings in a child with ITP?

A

Overall the kids feel pretty well
History of viral infection in the last 1-3 weeks
Clinical findings consistent with low platelets