Transcript Anemia Part II

ANEMIA - PART II
Anemia of Chronic Inflammation
BY: Zorawar Noor
4/21/2014
Objectives
 Understand the pathogenesis of anemia of
chronic inflammation (ACI)
 Review 4 Simple Laboratory Steps to diagnose
anemia (from Part I)
 Learn the characteristics lab findings of ACI
 Learn how to find coexisting iron deficiency
When to Suspect Anemia of
Chronic Inflammation?
 In inflammatory, infectious, and malignant
conditions (RA, SLE, osteomyelitis…)
 In cases with normocytic and normochromic
anemia (usually mild and asymptomatic)
Pathogenesis
 Inflammatory cytokine release (IL-6) triggers:
 Hepcidin
 Hepcidin decreases iron absorption in GI tract, and
makes macrophages hold onto iron
 Bone marrow is hypoproliferative despite having
slightly increased EPO levels
 EPO levels are not as high as they should be
 Unlike in iron deficiency anemia, where peripheral
RBCs gain a longer circulating half-life, there is shorter
RBC life span.
4 Steps to Classify Anemia
(Review from Part I)
 Step 1 – Characterize by MCV
 Microcytic, normocytic, macrocytic
 Step 2 - Identify Morphologies on Peripheral Smear
 E.g. hypochromia, bite cells, etc.
 Step 3 – Calculate Reticulocyte Index
 Reticulocyte Index (RI) = ReticCount * 0.5(Hct/45)
 Step 4 – Use iron studies, bone marrow biopsy, etc.
See presentation “Anemia, Part I” for more explanation of
each step
Diagnosis
 History: collagen vascular diseases,
malignancies, osteomyelitis, etc.
 Step 1) MCV initially normal
 Step 2) if chronic, can see mirocytosis and
hypochromia
 Step 3) Low Retic Count
 Step 4) normal or low iron, low TIBC, high ferritin
Iron Studies in ACI
Finding in Anemia of
Chronic Inflammation
Fe
Mildly low
TIBC
Low
% Sat
Mildly low
Ferritin
High – very high
MKSAP Case 2
 A 22-year old woman undergoes a new patient
evaluation. She was recently diagnosed with SLE.
Her menstrual pattern is normal, and her medical
history is otherwise noncontributory, her only
medications are hydroxychloroquine and a
multivitamin.
 On Physical exam: T37.2C, BP 126/78, P88, RR17,
and the patient has a malar rash, thinning hair, but
no joint abnormalities, oral lesions, pericardial or
pleural rubs, or heart murmurs.
 Laboratory studies: Hgb 8.2, WBC 3900, Ferritin 556,
Iron 18, Retic Count 2%, TIBC 180, Transferrin sat
10%, and creatinine 1.0.
…MKSAP Case 2
…MKSAP Case 2
 Which of the following is the most likely
diagnosis?
 (A) inflammatory anemia
 (B) iron deficiency
 (C) microangiopathic hemolytic anemia
 (D) Warm Ab-associated hemolysis
Answer Explanation
 History of SLE
 Step 1) MCV is low late in inflammatory anemia
 Step 2) Hypochromia is noticeable, also late finding
 Step 3) low RI is consistent with Inflammatory Anemia
 Step 4) Ferritin is high from inflammation, TIBC is low (
think of iron being stored away from pathogens
needing it for their own use through hepcidin)
Finding Coexisting Iron
Deficiency
 Transferrin will often be reduced, not increased like it is
in iron deficiency anemia (IDA)
 Unlike usual Inflammatory anemia,
 Soluble transferrin receptor (sTfR)-ferritin index
 Ration of the sTfR to logarithm of ferritin
 If index <1.0 suggests pure inflammatory anemia
 If index >2.0, could be IDA or combination
 Bone Marrow biopsy (macrophages with iron in ACD)
Summary
 Just approach it one step at a time!
 Remember the pathogenesis of ACI, cytokines
cause hypo-proliferation and low-iron because
it stays in macrophages
 Always watch out for coexisting iron deficiency
 Treat the underlying cause.
References
 Harrison’s Principles of Internal Medicine
 Adamson JW. Chapter 103. Iron Deficiency and Other
Hypoproliferative Anemias. In: Longo DL, Fauci AS, Kasper
DL, Hauser SL, Jameson JL, Loscalzo J, eds. Harrison's
Principles of Internal Medicine. 18th ed. New York: McGrawHill; 2012.
http://www.accessmedicine.com/content.aspx?aID=91172
23. Accessed December 7, 2011
 Wians, F.H. and Urban JE. “Discriminating between
Anemia of Chronic disease Using Traditional Indices of
Iron Status v. Transferring Receptor Concentration”.
2001. American Journal of Clinical Pathology. Volume
115.
 UptoDate