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Anemia ANEMIA

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					ANEMIA IRON DEFICIENCY

December 2003

QOD #1
 A 13mo old girl has had increasing pallor and fatigue

for the last month. Lab findings reveal: Hgb 8g/dL; Hct 25; MCV 56; RDW 17.9; WBC 6,700 with 47% PMNs, 45% lymphs, 6% monos; and plts 501.  The MOST appropriate next step in management is to:
   



A. determines the child’s response to oral iron therapy B. measure the serum ferritin concentration C. measure the serum iron concentration and TIBC D. obtain a Hgb electrophoresis study E. perform a bone marrow aspiration

QOD #2
 Hematologic studies obtained during the routine

preschool physical exam of a 5 1/2y/o boy reveal: Hgb 10; MCV 63; RDW 13; retic count 2.1; WBC 7,600; plts 432.  Among the following, the MOST likely explanation for these findings is:
   



A. aplastic anemia B. G6PD deficiency C. hereditary spherocytosis D. iron deficiency anemia E. thalassemia minor

Learning Objectives
 Describe the approach to the anemic child  Discuss possible etiologies of anemia  Recognize characteristics of iron deficiency anemia

 Determine the treatment plan for iron deficiency  Explain the importance of recognizing and treating

iron deficiency

Anemia – in general
 The Definition:
  

A reduction in the red blood cell mass HgB concentration below the normal limit relative to healthy people* Not a particular entity, but a manifestation of pathology

 Numerous etiologies exist

 Your job!  Determine and correct the cause

Anemia – More Specifically
 Normal range of HgB/Hct varies
  

Age Gender Race

 Anemia = 2SD below the Hgb/Hct mean of

the appropriate healthy population


Hgb in blacks is 0.5g/dL lower than whites or hispanics

 2.5% of children are classified as anemic

Normal Values – Age and Gender

What’s normal?
 H/H– Anemia criteria  6-23 m  10/31  2-5 y  11/34  6-12 12/37
 MCV  Lower 70 + years in age (2-10)  Upper0.6/year + 84 (up to 96y)  RDW  11.5%-14.5%

 Reticulocyte count  Corrected 1%  Mentzer index  MCV/RBC  <12 thal trait  >13 Fe deficiency

Clinical Manifestations of Anemia
 Asymptomatic  Symptoms begin when HgB <7-8g/dL  Vague symptoms  Irritability  Fatigue  Dyspnea – especially with exertion  Weakness  Signs  Pallor  Tachycardia  Tachypnea  Congestive heart failure

Pallor

The Approach

Clues to the etiology are in the H&P

The Approach - History


 



  

Age:  Newborn period – hemolytic anemia, blood loss, Fe deficiency rare before 4-6mo old  3-6mo old – hemoglobinopathy, maybe iron deficiency  6-18mo old – iron deficiency most common, consider TEC  > 18mo – differential broadens Gender  Male – X-linked disease Race  AA – Sickle cell disease  Middle eastern, southeast asian, southern european – β thalassemia  AA and southeast asians – æ thalassemia Diet  Excessive cow’s milk consumption – Fe deficiency  Strict vegetarian – B12 deficiency  Goat’s milk as milk protein source – folate deficiency Drug history  Antibiotics, anti-inflammatory meds, anticonvulsants Infections FHx  Anemia? Gallstones? Splenectomy? Transfusions?

The Approach – Physical Exam
 Abnormal forearm and hand, café-au-lait macules,

short stature


Fanconi anemia

 Triphalangeal thumb  Diamond-Blackfan anemia  Frontal bossing, maxillary overgrowth  Congenital hemolytic anemia  Aortic stenosis, VSD  Microangiopathic hemolytic anemia  Splenomegaly  Inherited hemolytic anemia  Ataxia and posterior column signs  B12 deficiency

Labs are Helpful – Within Reason
 CBC with differential


Evaluate all cell lines

 Red cell indices


MCV and RDW = critical

 Peripheral smear  Reticulocyte count
 Coomb’s


If smear indicates hemolysis

MCV and RDW = Critical
 Low MCV = microcytosis  Increased RDW


Iron deficiency  Thalassemia trait  Hemoglobin EE disease  (lead poisoning)  (chronic disease)  High MCV = macrocytosis  Nutritional deficiency  Bone marrow failure

  

Helps distinguish between iron deficiency and thalassemia trait

Aplastic anemia Drug suppression Diamond-Blackfan

Normal Peripheral Smear

Hypochromic Microcytic

Iron Deficiency Anemia

Who Needs Iron and When?
 Everyone needs iron  Amount varies at different stages of growth/age  When is it needed?
 

Full term infant – by 4mo of age Premature infant – by 2-3mo old


Faster growth rate and less stores Especially adolescent female – when menses has begun



Adolescence


How Do We Decide… How Much is Enough?
 Healthy full term infant
 

1mg/kg/day by 4mo old until 3y/o 2mg/kg/day


If low birth weight infant

 4-10y/o


10mg/day

 ≥11y/o  18mg/day

Where is the Iron? For Infants…
 Breast milk
 

0.5 –1.0 mg of Fe/L >50% absorption

 Cow’s milk  0.5-1.0 mg of Fe/L  10% absorbed*  Formula (cow’s milk based)  12 mg of Fe/L  4% absorbed

AAP Recommendations for Infants
 If exclusive breastfeeding post 6mo old  Start 1mg/kg/day iron supplement  Continue maternal vitamins  If not breastfed  Iron fortified formula during 1st year of life  Iron-fortified cereal at 4-6months old
 No whole cow’s milk during 1st year of life


Possible trigger for occult GI bleed

Where is the Iron? For Everyone Else…
 Heme – 10% of dietary iron  Non-heme – 90% of dietary iron  From Hgb and myoglobin of meat  Absorption varies depending on rest of diet  Easily absorbed  Promoted by:  Rest of diet does not  Vit C matter  Heme iron - meat  Promotes non-heme iron  Inhibited by: absorption
 Dairy, bran, vegetable fiber, tannins in tea

Most kids eat very little meat!

OJ: Doubles absorption from a meal Tea: Decreases the absorption by 75%

Making Your Diagnosis
 History and physical = most important  Labs
 

CBC with differential and smear Red cell indices


MCV and RDW = critical Not necessarily needed if H&P strongly suggest Fe deficiency as cause of anemia



Reticulocyte count


 If an unusual hx, or age < 6 mo or >18 mo-2y/o, then

other labs are needed*

Iron Deficiency Anemia Labs


In order of changes that occur
   

RDW increases Serum Fe levels fall MCV decreases HgB/Hct drops



Other labs may be done – but not necessary

You Suspect or Have Made Your Diagnosis! Now What?
 Start treatment  Diet changes and Fe supplement  Will confirm your diagnosis  Expect lab changes if dx is correct  Increased reticulocyte count within 1wk  Increased HgB by 1g/dL within 1mo*  Treat for 2-3mo  Need to replenish stores

Why Should We Care So Much?
 5 different studies demonstrate:


Association of Fe deficiency and behavior changes Lower scores on the Bayley mental-developmental index



 Correction of iron deficiency:


Did NOT improve the test scores

 Resultant thought/hypothesis:


Iron deficiency anemia likely produces irreversible abnormalities in cognition

QOD #1


Hct 25; MCV 56; RDW 17.9; WBC 6,700 with 47% PMNs, an unusual hx, or age <monos; and plts 501. If 45% lymphs, 6% 6 mo or >18 mo-2y/o, then other labs are  The MOST appropriate next needed* management is step in to:
   

Labs CBC with differential and smear A 13mo old girl has Red cell indices had increasing pallor and fatigue for the last month.MCV and RDW = critical Hgb 8g/dL; Lab findings reveal: Reticulocyte count



A. determines the child’s response to oral iron therapy B. measure the serum ferritin concentration C. measure the serum iron concentration and TIBC D. obtain a Hgb electrophoresis study E. perform a bone marrow aspiration

What kind of anemia is this?

QOD #2

Microcytic anemia With Normal RDW

 Hematologic studies obtained during the routine

preschool physical exam of a 5 1/2y/o boy reveal: Hgb 10; MCV 63; RDW 13; retic count 2.1; WBC 7,600; plts 432.  Among the following, the MOST likely explanation for these findings is:
   



A. aplastic anemia B. G6PD deficiency C. hereditary spherocytosis D. iron deficiency anemia E. thalassemia minor

Expect high RDW

Happy December!!

Additional Labs
 Iron studies:
   

Ferritin TIBC FEP Iron
A2 and F quantification

 Hgb electrophoresis:


 ESR, UA, stool guiac  CBC and smear of parents

Microcytosis & Fe studies
Fe deficiency Thal trait Lead poisoning

Hgb MCV
RDW N

N N
N

FEP Serum Fe
TIBC

N N
N

N
N

Ferritin

N

N


				
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