Albumin adult levels

Phenytoin (Dilantin) [Anticenvulsant/Hydantoin] Uses Sz disorders Action X Sz spread in the motor cortex Dose Load Adults Peds. 15-20 mg/kg IV, 25 mg/min max or PO in 400-mg doses at 4-h intervals Maint Adults. Initial, 200 mg PO or IV bid or 300 mg hs then follow levels Peds. 4-7 mg/kg/24h PO or IV -s- daily-bid avoid PO susp (erratic absorption) Caution [D, +] Contra Heart block, sinus bradycardia Disp Caps, susp, inj SE Nystag-mus/ataxia early signs of tox gum hyperplasia w/ long-term use. IV BP, bradycardia, arrhythmias, phlebitis peripheral neuropathy, rash, blood dyscrasias, Stevens-Johnson synd Notes Levels Trough Just before next dose Therapeutic Peak 10-20 mcg/mL Toxic >20 mcg/mL phenytoin albumin bound, levels = bound free phenytoin w/ i albumin azotemia, low levels may be therapeutic (nl free levels) Interactions T Effects W/ amiodarone, allopurinol, chloramphenicol, disulfiram, INH, omeprazole, sulfonamides, quinolones, trimethoprim t... 

Recent publications signal the continued interest in the function of this protein. It has been called a stress enzyme, involved in influenza virus infection (Tomas and Toparceanu, 1986). An explanation for Wilson s disease in terms of a genetic defect resulting in failure to convert from a neonatal (i.e., low) level of ceruloplasmin and copper to a normal adult level has been reported (Srai et al., 1986). Tissue specificity for the binding of ceruloplasmin to membranes was demonstrated in a study investigating the possible role of ceruloplasmin-specific receptors in the transfer of copper from ceruloplasmin to other copper-containing proteins (Orena et al, 1986). Ceruloplasmin has been shown to be effective in transferring copper to Cu,Zn-SOD in culture (Dameron and Harris, 1987), as has copper albumin. In view of the variable content of copper in this protein, it is not clear which copper is transferred. 

Based on the international protein reference CRM 470, the recommended interim reference interval for albumin in serum of adults 20 to 60 years of age is 35 to 52g/L (3.5 to 5.2 g/dL). Albumin levels reach adult levels around 20 to 30 weeks of gestation and remain relatively constant until at least 20 years of age. Levels then slowly decrease with age in both sexes. Levels are lower in individuals living in the subtropics and tropics, probably because of higher immunoglobulin levels secondary to infection or parasitic infestation. Levels are very posture dependent, increasing by up to 10% to 15% if the individual is standing. 

AFP is a 70 kDa glycoprotein found in the circulatory system of the developing foetus. It is synthesized primarily by the yolk sac and (foetal) liver. AFP is present only in vanishing low quantities in the serum of adults (where it is replaced by serum albumin). Elevated adult serum levels of this marker are often associated with various cancers of the liver, as well as germ cell tumours. It is also sometimes expressed by gastric and pancreatic cancer cells. Although a useful tumour marker, increased serum AFP levels also often accompany cirrhosis and some other non-cancerous liver diseases. 

Once absorbed, foreign compounds may react with plasma proteins and distribute into various body compartments. In both neonates and elderly human subjects, both total plasma-protein and plasma-albumin levels are decreased. In the neonate, the plasma proteins may also show certain differences, which decrease the binding of foreign compounds, as will the reduced level of protein. For example, the drug lidocaine is only 20% bound to plasma proteins in the newborn compared with 70% in adult humans. The reduced plasma pH seen in neonates will also affect protein binding of some compounds as well as the distribution and excretion. Distribution of compounds into particular compartments may vary with age, resulting in differences in toxicity. For example, morphine is between 3 and 10 times more toxic to newborn rats than adults because of increased permeability of the brain in the newborn. Similarly, this difference in the blood-brain barrier underlies the increased neurotoxicity of lead in newborn rats. 

At birth, a full-term infant has a significantly lower plasma albumin level than does an adult, and therefore the number of drug-binding sites is substantially less. This situation necessitates a reduction in the total amount of drug administered. 

Copper is an essential trace element absorbed in the gut and transported to the liver bound to albumin. It is found in a variety of enzymes, including superoxide dismutase. In the bloodstream Cu is present mostly in ceruloplasmin. Tissues with a relatively high content of Cu are liver, heart, and brain. The RDA for Cu in normal, healthy adults is 0.9 mg day-1, but newborns usually have liver levels higher than those of adults. The concentration of Cu in mature milk ranges between 0.2 and 0.3 mg l-1 in colostrum it is higher (0.4-0.6 mg l-1), but decreases along the lactation period (see the Chapter 13 by de la Flor St Remy et al.). 

Nephelometry, immunoturbidimetry, electroimmunodiffu-sion, and RID are most often used for measurements of albumin and IgG in cerebrospinal fluid. Apparent absence of IgG may be due to its. degradation by proternases in the specimen. RIA is required for determination of specific pro-teins present in very low concentrations (e.g., IgM). The reference interval for albumin levels in lumbar CSF by RID is 17.7 to 25.1 mg/dL. IgA, IgD, and IgM, measured by RIA, are each normally less than 0.2 mg/dL. Reference intervals for IgG are age related their means increase from 3.5 mg/dL in the 15- to 20-year-old group to 5.8 in adults aged 60 or older. The usual reference interval for CSF IgG in adults is 0.8 to 4.2 mg/dL for total protein, 15 to 45 mg/dL. Total protein levels are considerably higher in neonates, and in healthy elderly adults, concentrations up to 60 mg/dL are considered normal. 

Plasma zinc levels vary with sex, age, time of day, geographic location, and time elapsed since the last meal prior to phlebotomy. The normal range for an adult is probably 70-95 jUg/dL of plasma. Approximately 60% of zinc in plasma is bound to albumin, 30-40% to an 2-macroglobulin of unknown function, and a small amount to transferrin (Chapter 29) and amino acids, particularly cysteine and histidine. Copper does not compete with zinc for binding sites on albumin. Zinc newly absorbed from... 

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