Necrolytic acral erythema (NAE) was first described in Egyptian patients in 1996 by El Darouti and Abu El Ela.  NAE has been referred to as a cutaneous marker of hepatitis C infection owing to its strong association with the infection. [2, 3] Most of the cases described in literature have been in Egypt, although there have been reports of necrolytic acral erythema around the world. The prevalence of hepatitis C infection is high in Egypt, at 15-20%, owing in part to parenteral antischistosomal therapy.  Necrolytic acral erythema manifests as well-circumscribed, dusky erythematous plaques with adherent scale. Lesions classically have an acral distribution. While the plaques are psoriasiform, they do not manifest an Auspitz sign as would be seen with psoriasis. Burning or pruritus may occur with active disease. Several cases of necrolytic acral erythema have been reported in patients without hepatitis C, suggesting that hepatitis C may not be the sole cause. [5, 6, 7] Some sources support zinc deficiency as a cause of necrolytic acral erythema. Indeed, oral zinc supplementation has been an effective treatment for in some cases. [8, 9] While zinc deficiency is reported in Egyptian populations of children and pregnant women, why Egypt is the epicenter of necrolytic acral erythema is not clear. It is speculated that the prevalence of necrolytic acral erythema will decrease worldwide with effective treatments available for hepatitis C. 
Authors debate whether necrolytic acral erythema is a distinct entity or a subtype of necrolytic migratory erythema. However, the distinct appearance and association with hepatitis C infection suggest that it is a unique entity. It has been speculated that viral load and viral genotype might play a role in necrolytic acral erythema. [11, 12] It seems that one reason for the underdiagnosis of necrolytic acral erythema is that it has a range of histology and clinical findings and thus is more of a reaction pattern (eg, a spectrum), rather than a sharply defined entity. 
Another debate has arisen regarding cases of necrolytic acral erythema that are seronegative for hepatitis C and whether these cases constitute a distinct and separate clinical subset of the condition. [14, 15]
It should be kept in mind that hepatitis C has many other associated clinical conditions that include not only necrolytic acral erythema but also autoimmune thyroiditis, diabetic nephropathy, renal membranoproliferative glomerulonephritis, insulin resistance, mixed cryoglobulinemia, immune complex deposition, non-Hodgkin lymphoma, sialadenitis, and sicca syndrome. These are related to (1) chronic inflammation, (2) immune complex deposition, and (3) immunoproliferative phenomenon.