IRIDA (Iron-refractory iron deficiency anemia) syndrome is a rare autosomal recessive iron metabolism disorder characterized by iron deficiency anemia (hypochromic, microcytic) that is often unresponsive to oral iron intake and partially responsive to parenteral iron treatment.

Hyperkeratosis is thickening of the outer layer of the skin, the stratum corneum, which is composed of large, polyhedral, plate-like envelopes filled with keratin which are the dead cells that have migrated up from the stratum granulosum.