Bluish skin discoloration and cyanosis
Deoxygenated hemoglobin equal to 2.5 g/dL or greater in blood causes bluish coloration called cyanosis.
Though the deoxygenated blood appears dark red, there are certain optical principles involved in its giving of different coloration.
Tissues are low in oxygen in cyanosis and are filled up with dark red deoxygenated blood in place of oxygenated bright red blood.
Darker blood generates shift in optical effects leading to bluish skin discoloration. Cyanosis can be due to many health problems and notable among them are all types of blood circulatory problems, all types of ventilatory problems and extreme cold.
In cyanosis two types of conditions are observed namely central and peripheral cyanosis. Circulatory or breathing problems cause reduced oxygenation of blood in the lungs and slowing down the oxygen circulation and the skin turns bluish. This is a serious situation can lead to lung or heart failure. In the peripheral cyanosis only the extremities become bluish due to inadequate blood oxygen supply. This can be corrected by increasing the oxygenated blood supply.
Raynaud's Phenomenon is a vasospastic disorder in which blood vessels in fingers and toes spasm, leading to vasoconstriction.
Raynaud's Phenomenon causes bluish color changes in the toes and fingers and their necrosis if unattended.
In Raynaud's Phenomenon the sympathetic nervous system is hyperactivated affecting the peripheral blood vessels and their extreme vasoconstriction leading to tissue hypoxia. Recurrent attacks can cause tissue damage, ulceration, gangrene and necrosis. Shifting to a warm room and keeping fingers in warm water may relieve the symptoms and restore blood circulation. Persons prone to attacks of Raynaud's Phenomenon are advised to keep themselves warm and if necessary use vasodilatory drugs under the advice of physician.
Methemoglobinemia is a blood disorder wherein, methemoglobin, an oxidised form of hemoglobin is present in levels above normal condition.
In methemoglobinemia, due to oxidative stress the oxygen carrying ferrous ion of hemoglobin molecule is oxidized to ferric state.
This is results in conversion of hemoglobin to methemoglobin which does not bind oxygen.
If the levels of methemoglobin are high in blood bluish chocolate-brown color is imparted to blood.
Methemoglobinemia impedes normal oxygen transport resulting in tissue hypoxia and bluish skin. Methemoglobinemia may be congenital with autosomal recessive inheritance pattern. Since congenital methemoglobinemia is recessive, there is a chance of inheritance in the offspring only if both the parents carry the gene. Patients with impaired production of NADH (the essential cofactor for diaphorase I) with the resultant pyruvate kinase deficiency have risk of getting methemoglobinemia and bluish skin.
Methemoglobinemia is acquired in people exposed to exogenous oxidizing drugs and chemicals. Antibiotics like dapsone, sulphonamides and trimethoprim can give rise to increased methemoglobin levels and methemoglobinemia. Certain local anaesthetics (prilocaine and articaine), chlorates, bromates, metoclopramide, nitrates and aniline dyes can also cause methemoglobinemia. Methemoglobinemia disorder can be treated with oxygen supplementation and administration of intravenous methylene blue 1% solution.
Mongolian spot is a congenital birthmark, which is flat, benign and harmless; it is sometimes mistaken as an injury or bruise during childbirth.
Mongolian spot exclusively involves skin and is due to melanocytes (melanin producing cells) embedded deep in the dermis.
Mongolian spot results from melanocytes entrapment in the dermis during their embryonic development.
Mongolian spot is usually a bluish skin and with irregular shape and wavy borders. Mongolian spot can appear as multiple skin discoloration spots usually on the shoulders, flanks, lower back and the buttocks. Mongolian spot is highly prevalent in East Asians, East Africans, Polynesians and Turkic people. As the child with Mongolian spot grows, the spot fades and disappears by puberty.
Localized argyria occurs due to continuous contact with silver and its compounds. Argyria is a harmless cosmetic problem which can be socially debilitating and mildly disfiguring. Though generally believed to be irreversible, avoidance of sun exposure and laser therapy appears to give good results.