Correction of iron deficiency with oral or intravenous iron
supplementation can reduce the severity of anemia in
patients with CKD.25,26 Untreated iron deficiency is an
important cause of hyporesponsiveness to ESA treatment.27,28
It is important to diagnose iron deficiency because treatment
can readily correct the associated anemia and investigation
for the cause of iron deficiency, which should follow its
detection, can lead to important diagnoses. In the absence of
menstrual bleeding, iron depletion and iron deficiency
usually result from blood loss from the gastrointestinal
tract. There are additional considerations in CKD patients
with iron deficiency. For instance, hemodialysis patients
are subject to repeated blood loss due to retention of blood in
the dialyzer and blood lines. Other contributing causes in
hemodialysis and other CKD patients include frequent
blood sampling for laboratory testing, blood loss from
surgical procedures (such as creation of vascular access),
interference with iron absorption due to medications
such as gastric acid inhibitors and phosphate binders,
and reduced iron absorption due to inflammation.29 The
reader is referred to standard textbooks of medicine and
pediatrics for more extensive discussions on the diagnosis
and evaluation of patients with known or suspected iron
deficiency