Xanthochromia

XANTHOCHROMIA (from Greek xanthos - yellow and chroma - color), a term applied to certain human tissues and body fluids when the latter are colored in a peculiar brownish- or greenish-yellow hue. In most cases, this involves coloration caused by hemoglobin breakdown products. This term is most commonly used in relation to the corresponding changes in the skin and cerebrospinal fluid. - Skin xanthochromia, manifested by its brownish-yellow coloration, is observed in hemolytic jaundice, especially in those forms that accompany septic diseases. - Cerebrospinal fluid xanthochromia is a pathological alteration of the latter, consisting in its coloration to a greenish-yellow color. According to its origin, two types of cerebrospinal fluid xanthochromia are distinguished: hemorrhagic, formed as a result of hemorrhages into the cerebral ventricles or into the spinal canal, and congestive, developing as a result of stagnation in the vessels of the membranes and brain and in the cerebrospinal fluid. - Hemorrhagic cerebrospinal fluid xanthochromia is observed in cerebral hemorrhages, hemorrhagic meningitis of various etiologies, uremic and epileptic seizures if the latter are accompanied by hemorrhages into the subarachnoid space, etc. Its distinguishing features are: 1) erythrocytes are often detected in the fluid; 2) the fluid is colored along the entire extent of the spinal canal; 3) over time, the coloration weakens and then disappears; 4) the protein content in the fluid is relatively low (up to 2-3 %), and the fluid is not prone to forming a massive gelatinous clot. - Congestive cerebrospinal fluid xanthochromia develops during processes leading to limited compression of the vessels of the membranes and brain and to the formation of a subarachnoid block. Vascular congestion on the one hand, and disruption of the normal circulation of the fluid below the block on the other, cause the penetration of plasma and blood coloring matter into the cerebrospinal fluid and their accumulation in the closed part of the spinal canal. Among such processes, xanthochromia is most often accompanied by extramedullary spinal tumors, processes in the vertebrae secondarily compressing the spinal cord, and localized inflammatory processes in the spinal canal that close its lumen with edematus tissues or adhesions of the membranes. In addition, congestive xanthochromia is also observed in diseases not accompanied by compression of the spinal cord: in multiple radiculitis, Landry's paralysis, general venous congestion due to heart failure, pneumonia, and carbon dioxide poisoning. In these latter cases, the cause of xanthochromia lies either in local or general congestion in the vascular system and the associated disruption of the proper circulation of the cerebrospinal fluid. The signs of congestive xanthochromia are as follows: 1) the fluid is colored below the subarachnoid block and is not colored above it; only in general diseases and multiple radiculitis can it be colored along the entire extent of the spinal canal; 2) the coloration increases over time; 3) the fluid is rich in protein (up to 50 ^o/_oo) and contains no cellular elements (so-called albumin-cytologic dissociation, which always precedes the appearance of coloration); 4) the fluid is prone to forming a massive gelatinous clot (Froin's syndrome). A separate category is the coloration of the fluid observed in jaundice and associated with the penetration of bile pigments into the fluid.