A 47 year old female was referred for evaluation of chronic anemia of unknown etiology. Patient was anemic since childhood and was on iron supplements but got worsened in last 1.5 years warranting hospitalizations and blood transfusions. Patient endorsed to have dizziness, fatigue, poor exercise tolerance, dyspnea and palpitation associated with exertion. Review of system was negative for any active bleeding, epigastric pain or melena. Her menstrual cycles were regular with normal flow. Family history was significant for anemia in her niece. Laboratory values showed severe microcytic hypochromic anemia (Hemoglobin-4.5, Mean Corpuscular Volume-70, Mean Corpuscular Hemoglobin Concentration-28, Red cell Distribution Width-24) and iron panel revealed low serum iron and transferrin saturation with normal serum transferrin and unexpectedly normal serum ferritin. White cell count was normal (12.1) and platelet count was increased (443). There was no clinical or lab evidence of chronic inflammatory state or hemolysis and hemoglobin electrophoresis did not detect any hemoglobinopathy. Stool occult blood and Helicobacter Pylori antigen were negative. Esophagoduodenoscopy and Colonoscopy were unremarkable. Serum vitamin B12 and folic acid were normal. Serum anti transglutaminase antibody, parietal cell and castles intrinsic factor antibody were negative. Serum hepcidin was found to be inappropriately high. Presence of high hepcidin suggested a diagnosis of iron-refractory iron deficiency anemia (IRIDA), which was eventually confirmed by identification of a novel heterozygous TMPRSS6 mutation. Patient was treated with blood transfusion and parenteral iron therapy which she may require in future as well.
In patients referred for hematologic evaluation with refractory IDA, screening for celiac disease, autoimmune gastritis, Helicobacter pylori, and hereditary forms of IDA is recommended. Although iron deficiency anemia is relatively common, the prevalence of the iron-refractory form of the disease is unknown.. Mutations of the TMPRSS6 gene have been associated with a rare autosomal recessive disorder characterized by iron deficiency anemia termed IRIDA.The current treatment of IRIDA is based on parenteral iron administration; in the future, manipulation of the hepcidin pathway might become an alternative therapeutic approach.
The typical features of IRIDA are hypochromic, microcytic anemia with a very low mean corpuscular volume of erythrocytes, low transferrin saturation, no (or inadequate) response to oral iron, and only a partial response to parenteral iron. In contrast to classic iron deficiency anemia, serum ferritin levels are usually low-normal, and serum or urinary hepcidin levels are inappropriately high for the degree of anemia. This case suggests that serum hepcidin should be routinely measured for differential diagnosis when patients with IDA are unresponsive to oral iron or have unusual clinical features.
To cite this abstract:Panginikkod S, Gopalakrishnan V, Parikh MP. A Rare Case of Iron Refractory Iron Deficiency Anemia (Irida). Abstract published at Hospital Medicine 2016, March 6-9, San Diego, Calif. Abstract 723. Journal of Hospital Medicine. 2016; 11 (suppl 1). https://www.shmabstracts.com/abstract/a-rare-case-of-iron-refractory-iron-deficiency-anemia-irida/. Accessed January 23, 2020.