Creatinine, serum concentrations normal

Elevated serum creatinine concentration (normal range approximately 0.6 to 1.2 mg/dL [53 to 106 pmol/L])... 

When 60 patients (22 men, 38 women) who had taken lithium for 1 year or more (mean 6.9 years mean serum concentration 0.74 mmol/1) were interviewed about adverse effects, 60% complained of polyuria-polydipsia syndrome (serum creatinine concentrations were normal) and 27% had hypothyroidism requiring treatment (108). Weight gain was more common in women (47 versus 18%) as were hypothyroidism (37 versus 9%) and skin problems (16 versus 9%), while tremor was more common in men (54 versus 26%). Weight gain of over 5 kg in the first year of treatment was the only independent variable predictive of hypothyroidism. 

A 56-year-old man with normal renal function and therapeutic lithium concentrations became toxic (serum concentration 2.53 mmol/1 24 hours after the last dose) with renal impairment (serum creatinine 141 gmol/l 1.6 mg/ dl) within days of starting levofloxacin. Both symptoms and laboratory abnormalities resolved with withdrawal of both lithium and levofloxacin (615). 

Reduced tobramycin clearance can be associated with a normal creatinine clearance in serum concentration-adjusted dosage of once-daily tobramycin therapy in critically ill patients (42). 

In patients with normal renal function, 70 to 90% of an intravenous dose of vancomycin is excreted in the urine unchanged by glomerular filtration. The serum elimination half-life in patients with normal renal function is variable, but averages 6 hours [171]. However, terminal half-lives ranging from 3 to 11 hours have been observed [184]. In anuric patients, the serum half-life increases markedly to 6 to 10 days [171]. The liver may also be involved in the disposition of vancomycin as dose adjustments have been required in patients with severe liver dysfunction [172]. An interesting study by Golper et al that compared systemic vancomycin clearance simultaneously with the renal clearances of vancomycin, creatinine, inulin and para-aminohippurate demonstrated a substantial non-renal clearance of vancomycin of 30%. In addition, the researchers found that the non-renal clearance of vancomycin was concentration dependent with a 10% greater clearance at serum concentrations of 14 mg/ ml as compared to 7 mg/ ml [185]. 

Figure 24-10 Receiver operating characteristic (ROC) curves comparing creatinine and cystatin C in the assessment of GFR. Non parametric ROC plots were constructed to assess the diagnostic accuracy of serum concentrations of cystatin C and creatinine in distinguishing between normal and reduced GFR (less than 80mL/min per 1.73 m ) in 51 patients with various renal conditions. (From Kyhse-Andersen j, Schmidt C, Nordin C, et af. Serum cystatin C, determined by a rapid, automated particle-enhanced turbidimetric method, is a better marker than serum creatinine for glomerular filtration rate. Clin Chem 1994 40 l92l-6.)...

It should be noted that initially the urea and creatinine may be normal in ARF. The serum potassium usually rises very quickly in catabolic patients, with or without tissue damage, and falls quickly once the urine flow rate increases. The urine volume cannot be related to the GFR. The serum urea and ereatininc remain high during the diuretic phase, because the GFR is still low and the large urine volumes rcllect tubular damage. In the recovery phase the serum urea and creatinine fall as the GFR improves and the. serum potassium concentration returns to normal, as the tubular mechanisms recover. 

Daptomycin is poorly absorbed orally and should only be administered intravenously. Direct toxicity to muscle precludes inttamuscular injection. The steady-state peak serum concentration following intravenous administration of 4 mg/kg in healthy volunteers is approximately 58 pg/mL. Daptomycin displays linear pharmacokinetics at doses up to 8 mg/kg. It is reversibly bound to albumin protein binding is 92%. The serum half-life is 8 to 9 hours in normal subjects, permitting once-daily dosing. Approximately 80% of the administered dose is recovered in urine a small amount is excreted in feces. Dosage adjustment is required for creatinine clearance below 30 mL/minute this is accomplished by administering the recommended dose every 48 hours. For hemodialysis patients, the dose should be administered immediately after dialysis. 

Serum creatinine concentration is constant unless there is a change in the rate of production of creatinine in the body or creatinine clearance. The creatinine clearance in normal kidneys is approximately 110 to 130 mL/min. This value declines with progressive renal impairment, and it drops to zero with severe renal impairment. Creatinine clearance values of 20 to 30 mL/min signify moderate renal impairment values of less than 10 mL/min signify several renal impairment. 

The PLS trials were preceded by a normalization stage (aU spectra were normalized to a common integrated intensity in the SCN absorption at 2060cm ). The second derivatives of the normalized spectra then served as the basis for the analyses. Scatterplots comparing the reference analytical levels to the IR-predicted albumin, total protein, glucose, cholesterol, tri ycerides, and urea are shown in Figure 12. The corresponding PLS models and their analytical accuracies are compiled in Table 4. Attempts to quantitate uric add and creatinine proved unsuccessful due to their relatively low serum concentrations. 

Acid-base balance Of 16 patients with hepatic cirrhosis and chronic hepatitis B infection, five developed lactic acidosis after 4—240 days of treatment with entecavir all five had highly impaired liver function [13 ]. One patient died, but in the other four the lactic acidosis resolved after withdrawal of entecavir. The serum lactate concentrations were not increased in the other 11 patients, who all had less severe liver impairment. Child-Pugh scores did not correlate with the development of lactic acidosis, but MELD (Model for End-Stage Liver Disease) scores did, as did serum bilirubin, creatinine, and international normalized ratio (INR). The authors suggested that entecavir should be used cautiously in patients with severely impaired liver function. 

Mineral and metal metabolism An 18-year-old woman, with a history of abdominal surgery for type B intestinal neuronal dysplasia, developed diffuse muscle weakness, carpopedal spasm, tetany and confusion 6 h after intake of the last dose of an oral phosphate solution (Fleet Phosphosoda ) prescribed as bowel preparation for colonoscopy. These symptoms were associated with elevations in serum creatinine, potassium and phosphorous levels and decreases in glomerular filtration rate, sodium and calcium levels. Following repeated sessions of haemodialysis, both calcium and phosphorous serum concentrations returned to normal levels after a day. In contrast, the glomerular filtration rate started to return to baseline after 4 days [74 ]. 

Flucytosine is usually administered intravenously over 20 to 40 minutes. Protein binding is low (approximately 2-4%) and volume of distribution is high (0.7-1 L/kg) with cerebrospinal fluid (CSF) concentrations comparable to serum concentrations. Approximately 90% of a dmg dose is excreted unchanged in the urine. The dmg has a half-life of 3-6 hours in adult patients with normal renal function. Patients with renal impairment should be given smaller doses which can be estimated according to their creatinine clearance. Only a small percentage of flucytosine is metabolised to 5-fluorouracil by the body, with an area under... 

Cardiac index and blood pressure must be sufficient to ensure adequate organ perfusion, as assessed by alert mental status, creatinine clearance sufficient to prevent metabolic azotemic complications, hepatic function adequate to maintain synthetic and excretory functions, a stable heart rate and rhythm, absence of ongoing myocardial ischemia or infarction, skeletal muscle and skin blood flow sufficient to prevent ischemic injury, and normal arterial pH (7.34 to 7.47) with a normal serum lactate concentration. These goals are most often achieved with a cardiac index greater than 2.2 L/min/m2, a mean arterial blood pressure greater than 60 mm Hg, and PAOP of 25 mm Hg or greater. 

Baseline tests CBC, hepatic function, pregnancy test, TSH, renal function, uric acid, HCVRNA level. Exclusions to treatment platelet count <90,000 cells/mm (as low as 75,000 cells/mm in patients with cirrhosis) absolute neutrophil count < 1,500 cells/mm serum creatinine concentration > 1.5 X upperlimit of normal abnormal thyroid function... 

A 62-year-old man treated with continuous mediastinal irrigation with a 1 10 solution of povidone-iodine developed seizures on the fifth day of drainage (14). After the seizure, his serum iodine concentration was raised (120 pg/ml). Renal insufficiency developed at the same time. The electroencephalogram showed no evidence of epileptic activity or other abnormalities. The povidone-iodine irrigation was replaced by continuous irrigation with a solution of neomycin and polymyxin B. Renal function improved and the creatinine concentration returned to normal 3 days after the seizure. 

This case prompted a report of 10 metformin- associated patients with cobalamin deficiency among 162 patients with vitamin Bi2 concentrations below 200 pg/ml (91). They had taken a mean dose of metformin of 2015 mg/ day for an average of 8.9 years. The mean vitamin B12 concentration was 140 pg/ml. All had normal serum folate and creatinine concentrations and no antibodies to intrinsic factor. In one patient there was malabsorption. 

A 70-year-old man survived a suicidal attempt with metformin 63 g (132). His serum lactate concentration was 24 mmol/1 and creatinine 216 pmol/1. He received bicarbonate hemodialysis, blood pressure support, and active warming for hypothermia. After 6 hours lactate and creatinine normalized. 

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