Iron Deficiency Anemia and Chronic Kidney Disease Glossary of Terms


Inability of the blood to supply adequate oxygen to the body’s tissue and organs due to the shortage of red blood cells or hemoglobin; defined as hemoglobin <12 g/dL in women and <13 g/dL in men.

Chronic Kidney Disease

Gradual loss of kidney function; top 10 leading cause of death in the U.S.


Process of making red blood cells.


A protein produced by the kidney that leads to the formation of red blood cells in the bone marrow.


A blood cell protein that contains iron; inflammation causes increased serum ferritin. Serum ferritin tests are one measure used to diagnose iron deficiency anemia.


One of two forms of supplemental iron. Ferric refers to iron-containing materials or compounds. In chemistry the term is reserved for iron with an oxidation number of +3, also denoted iron(III) or Fe3.


Ferrous refers to iron with oxidation number of +2, denoted iron(II) or Fe2. Ferrous sulfate is a common over-the-counter oral iron.

FGF 23

Fibroblast growth factor 23 is a bone-derived protein that plays an essential role in phosphate and vitamin D balance. Low iron levels are associated with increased levels of FGF23. High levels are associated with increased rates of mortality. FGF23 levels rise progressively in CKD


Glomerular filtration rate indicates how much blood is passing through the glomeruli in the kidneys each minute, basically a measure of kidney function.


The protein molecule in red blood cells that carries oxygen to tissue and organs throughout the body.


Hepcidin is a liver-derived peptide that controls iron absorption in the gut. Excess hepcidin restricts iron absorption and leads to iron deficiency. Chronic inflammation leads to excess production of hepcidin.


Inflammation is part of the body’s response to harmful stimuli. People with chronic kidney disease are in a state of chronic inflammation.

Iron Deficiency Anemia

A form of anemia due to low iron levels (as measured by TSAT and serum ferritin levels) – lead to low hemoglobin. Iron deficiency is the most common cause of anemia in CKD patients


Kidney Disease Improving Global Outcomes – Guidelines from the official journal of the International Society of Nephrology


Kidney Disease Outcomes Quality Initiative — the National Kidney Foundation’s practice guidelines.

Stages of CKD

There are five stages of CKD as measured by GFR. Stage 1 = GFR > 90 mL/min; Stage 2 = GFR 60 – 89 mL/min; Stage 3 is moderate CKD = GFR 30 – 59 mL/min; Stage 4 is severe CKD = GFR 15 – 29 mL/min; Stage 5 = GFR <15 mL/min.

Transferrin Saturation (TSAT)

TSAT is the percentage of iron binding by the major plasma iron transport protein, measured in the blood to detect iron excess or deficiency.

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