Urinary urea nitrogen

In some patients with IgA nephropathy (IgAN), intraglomerular coagulation plays a role in depositing fibrinogen (235,236). IgAN patients treated with urokinase show a marked improvement in urinary protein concentration, semm creatinine, and blood urea nitrogen levels (237). 

The increase in diet-tissue spacing has been proposed to be caused by the effects of water and heat stress on urinary nitrogen excretion. The model has been described in detail previously (Ambrose 1991) and will be briefly summarized here Nitrogen is excreted mainly as urinary urea. Its 6 N value is substantially (2-5%o) more negative than that of the diet (Steele Daniel 1978 Yoneyama et al. 1983). Under heat and water stress the concentration... 

Monitor the patient for resolution of hematuria after each successive therapeutic intervention. Frequency of monitoring is based on the severity of hemorrhaging. Monitor urinary output and serum chemistries (including sodium, potassium, chloride, blood urea nitrogen, and serum creatinine) daily for renal dysfunction. Check the CBC at least daily to monitor hemoglobin and platelet count. 

Blood lead levels, urinary lead levels, serum creatinine, blood urea nitrogen (BUN), creatinine clearance (CCT), and NAG were measured in 158 male and 51 female workers in a lead battery factory or a lead smelting plant in Japan (Ong et al. 1987). Controls consisted of 30 professional and laboratory staff members with no history of renal disease or lead exposure. The length of exposure to lead averaged 10.8 8.0 years with a range of 1-36 years. Exposure levels were not available, but indicators of lead body burden in the exposed workers were PbB level = 3.0-80.0 pg/dL and urinary lead level =... 

None of the exposures produced changes in clinical chemistry values (blood count, blood nitrate, blood urea nitrogen, serum enzymes, and serum electrolytes or urinalysis and nitrate and nitrite urinary excretion), spontaneous electrical activity of the cortex of the brain (detected by EEG), pulse rate and sinus rhythm, or pulmonary function. Visual and auditory acuity, exercise EKG, and time estimation tests did not differ from control values for any of the exposures. Only one of several cognitive tests was affected by exposure and the change occurred only in the four subjects exposed at 1.5 ppm. The test was taken during the time the subjects were experiencing severe headaches. 

Renal Effects. Urinary parameters (blood urea nitrogen, pH, osmolality, voliune, protein, sugar, and sediment) were normal in female dogs exposed to 3,3 -dichlorobenzidine (10.4 mg/kg/day) throughout a 7-year study in which female dogs were exposed to 10.4 mg/kg/day 3,3 -dichlorobenzidine. At necropsy, no histological effects to the kidneys were reported in any of the dogs (Stula et al. 1978). 

Drug/Lab test interactions The antianabolic action of tetracyclines may cause an increase in blood urea nitrogen. During doxycycline or minocycline therapy, false elevations of urinary catecholamine levels may occur... 

Blood pressure, pulse, serum electrolytes, urine volume, urinary sodium, serum creatinine, blood urea nitrogen, electrocardiogram, hepaticfunctiontests, infusion rate... 

Renal Effects. Evidence of renal damage was observed in individuals burned once with white phosphorus. Increased blood urea nitrogen (Summerlin et al. 1967), increased urinary levels of protein and urea nitrogen (Walker et al. 1947), and signs of acute renal failure (Songetal. 1985) have been observed. No longer term human studies were identified. Some of the blood/serum chemical changes are also found in thermal bum patients and cannot necessarily be ascribed to white phosphorus toxicity. However, controlled animal studies (discussed below) have shown similar effects that have been attributed to white phosphorus. 

While low serum cholesterol levels have been observed in malnourished patients, largely as a result of decreased synthesis of lipoproteins in the liver, hypocholesterolemia occurs later in the course of malnutrition and is therefore not useful as a screening test. PEM usually results in low serum urea nitrogen (BUN), urinary urea, and total nitrogen. Estimation of 24-h urine creatinine excretion is also a valuable biochemical index of muscle mass (when there is no impairment in renal function). The urinary CHI is correlated to lean body mass and anthropometric measurements. In edematous patients, for whom the extracellular fluids contribute to body weight and spuriously high body mass index values, the decreased CHI values are especially useful in diagnosing malnutrition. 

Aerobic exercise usually increases the percentage of muscle mass due to a decrease in body fat, but produces no absolute change in the amount of muscle. Aerobic exercise has been shown to alter protein metabolism including increases in amino acid oxidation with specific effects on the branched-chain amino acid leucine, increased urinary urea, and increased sweat nitrogen. 

A 43-year-old woman with rheumatoid arthritis developed dizziness having taken celecoxib 200 mg/day for 2 weeks. At the start of treatment she had normal renal function (104). Her serum creatinine was 670 pmol/l (7.4 mg/dl) and blood urea nitrogen 30 mmol/1 (90 mg/dl). Creatinine clearance was 16 ml/minute. Urinalysis was normal and casts were not present. Urinary chemical analysis showed a sodium concentration of 18 mmol/1, a fractional excretion of sodium of 0.3, and a renal failure index of 0.493, consistent with prerenal acute renal insufficiency. Celecoxib was withdrawn. Although her renal function then improved, her serum creatinine was still abnormal (4.7 mg/dl) 1 month later. 

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