Postobstructive diuresis. Studies in a dialyzed patient with a solitary kidney

Urinary excretion was studied in a volume-expanded, dialyzed patient who experienced a profound diuresis after passage of a uric acid calculus which had obstructed the ureter of his solitary horseshoe kidney. Natriuresis (23 per cent of the filtered load of sodium at peak flow) was accompanied by massive urinary losses of water, potassium, magnesium, calcium, bicarbonate, phosphate and uric acid. The data suggest that inhibition of proximal tubular reabsorptive processes was the major factor producing diuresis. Persistent free water clearance and initial potassium secretion indicate that the function of the distal tubule was largely intact. This diuretic pattern in association with retained ability to modulate sodium excretion after completion of diuresis suggests that volume expansion was the primary cause of blockade to proximal tubular reabsorption. Recommendations are made for the clinical management of the patient with diuresis after relief of obstruction.     

Uric Acid,Xanthine Oxidase and Other Risk Factors of Hypertension in Normotensive Subjects

Uric acid produced by xanthine oxidase (also a source of superoxide radicals) has been known to increase in hypertensive patients. In this study we evaluated the possible involvement of uric acid and xanthine oxidase in the pathogenesis of hypertension by examining their association with mean arterial pressure (MAP) and factors related to blood pressure. These factors include age, quetelet index (weight/height²) Cholesterol, creatinine, calcium (Ca), magnesium (Mg), sodium (Na), potassium (K) and urea. Fifty Two (male-19, female-33) normal healthy individuals were studied. Correlation studies of demographic variables showed that age was positively correlated with MAP [r=0.309, p=0.026] and cholesterol [r=0.503, p=0.000] while quetelet index was positively correlated with age [r=0.422. p=0.000] MAP [r=0.331, p=0.016] and xanthine oxidase [r=0.331, p=0.016]. MAP was positively correlated with uric acid [r=0.511, p=0.000], cholesterol [r=0.492, p=0.000] and xanthine oxidase enzyme activity [r=0.388, p=0.004] and negatively correlated with plasma calcium [r=-0.603, p=0.000]. Correlation studies of measured parameters with uric acid and xanthine oxidase showed that uric acid was positively correlated with creatinine [r=0.627, p=0.000]. plasma magnesium [r=0.442, p=0.001] and negatively correlated with plasma calcium [r=-0.546, p=0.000] while xanthine oxidase was negatively correlated with plasma calcium [r=-0.404, p=0.003] and plasma sodium [r=-0.288, p=0.038]. Stepwise multiple regression with MAP as dependent variable showed that 65% of total variability of blood pressure can be accounted for by plasma calcium, cholesterol, creatinine, plasma K, plasma Na, uric acid and xanthine oxidase in order of increasing R2 [xanthine oxidase : T-value = 3.26, R' = 0.6531. It can be concluded that in normotensive subjects, uric acid and xanthine oxidase have significant association with blood pressure and thus are one of the many factors which are involved in the cause or effect of hypertension.     

Renal tubular function in cyclosporine-treated patients

Renal tubular function was studied in 32 consecutive patients treated with cyclosporine for autoimmune uveitis. Cyclosporine dosage was modified to maintain the serum creatinine level at less than 2 mg/dl. No evidence of aminoaciduria, glucosuria, hypokalemia, hypophosphatemia, or hypouricemia indicative of the Fanconi syndrome was detected during three to six months of observation. The renal tubular reabsorption of phosphate, determined by renal threshold phosphate concentration (TmPO4/GFR), remained unchanged. An early decrease in the serum magnesium level was accompanied by a decrease in daily urinary magnesium excretion. Concurrent with the development of a mild reduction of the glomerular filtration rate, the fractional excretion of magnesium was slightly higher and that of calcium was lower than pretreatment values. There were modest elevations of serum uric acid and potassium values. Furthermore, lysozymuria was not observed. Thus, the alterations in tubular functions observed in our cyclosporine-treated patients are comparable to those associated with mild chronic renal insufficiency of various causes and are not specific manifestations of cyclosporine tubular toxicity.     

Effects of the N/L‐Type Calcium Channel Blocker Cilnidipine on Nephropathy and Uric Acid Metabolism in Hypertensive Patients With Chronic Kidney Disease (J‐CIRCLE Study)

This study assessed the urinary albumin/creatinine ratio (ACR) and uric acid metabolism in 70 hypertensive patients with chronic kidney disease in whom urinary ACR had remained ≥30 mg/g under the treatment of the L‐type calcium channel blocker amlodipine. Three months after switching to the N/L‐type calcium channel blocker cilnidipine, blood pressure (BP) did not change; however, urinary ACR significantly decreased with cilnidipine. Serum uric acid levels showed no significant change. In cases where uric acid production had been high (urinary uric acid/creatinine ratio ≥0.5), the urinary uric acid/creatinine ratio decreased significantly after cilnidipine treatment, suggesting that cilnidipine can suppress excessive uric acid formation. These results suggest that switching from amlodipine to cilnidipine results in a significant reduction in urinary ACR as well as significant reduction in uric acid production. Thus, cilnidipine is more useful than amlodipine in improving albuminuria and uric acid metabolism in hypertensive patients with chronic kidney disease.     

Changes in serum phosphate during beta-blockade in healthy men are not due to changes in the renal handling of phosphate

Serum parathyroid hormone (PTH), phosphate, ionized calcium, magnesium, alkaline phosphatase and creatinine and the urinary excretion of phosphate and creatinine were studied after 1 and 3 weeks beta-blockade in 32 young healthy men given either atenolol at 50 mg, metoprolol at 100 mg, propranolol at 80 mg or placebo twice a day. After 1 week treatment serum phosphate (mean (range] increased in the propranolol-treated subjects (1.17 (0.99-1.30) to 1.32 (1.08-1.71) mmol l-1 (P = 0.03), minor changes were found in the atenolol and the metoprolol-treated subjects but not in the placebo group. Serum phosphate was unchanged compared to pretreatment values after 3 weeks. Renal clearance and urinary excretion of phosphate and creatinine was unchanged after both 1 and 3-weeks treatment. Serum PTH, ionized calcium, magnesium and alkaline phosphatase were unchanged in all groups, whereas serum urate and creatinine increased in the metoprolol-treated subjects after both 1 and 3 weeks.     

Evaluation of kidney damage in patients with acute lymphoblastic leukemia in long-term follow-up: value of renal scan

In order to evaluate potential long-term kidney damage of childhood leukemia and risk factors affecting renal damage, we studied 116 children treated for acute lymphoblastic leukemia (ALL) using the St. Jude Total XI and XIII protocols in 1991-1998. The median follow-up period after the completion of treatment was 35 months. The following parameters were examined: urinalysis, urinary creatinine (Cr), calcium (Ca), phosphorus, beta2-microglobulin, glomerular filtration rate (GFR), tubular phosphorus reabsorption (TPR), and renal function tests. Radiological evaluation included renal ultrasonography (US), and renal scans with DMSA or MAG-3 were performed. Blood chemistry and renal US patients were normal in all patients except two. GFR, TPR, urinary Ca/Cr, beta2-microglobulin, and renal scan were abnormal in 19.0%, 16.4%, 13.8%, 6.0%, and 40.5% of patients, respectively. The abnormality rate in GFR was significantly higher in patients <2 years of age. TPR abnormality was found to be significantly higher in patients who did not have G-CSF. An abnormal renal scan was associated with Hb < 10 g/dL, kidney infiltration, or hypertension at presentation and also occurred patients who underwent methotrexate treatment with frequent intervals during the follow-up period. Patients should be followed-up after cessation of therapy with the conventional tests mentioned above. In case of any abnormality, further detailed tests should be performed; renal scan seems to be more predictive for renal damage.     

Risk factors for nephrolithiasis in patients with familial idiopathic hypercalciuria

PURPOSE: About 40% of patients with nephrolithiasis have idiopathic hypercalciuria, sometimes associated with a family history of kidney stones. In these families, little is known about the frequency of, and risk factors for, stone formation among hypercalciuric patients. We therefore conducted a prospective study of 216 subjects from 33 families with idiopathic hypercalciuria. MATERIALS AND METHODS: We recorded the age, weight, and history of calcium stones in all subjects, and measured 24-hour urine volume and excretion of calcium, uric acid, sodium, magnesium, urea, citrate, phosphate, and sulfate on a nonrestricted diet. We performed a more complete metabolic evaluation in many of the hypercalciuric subjects (calciuria/weight >0.1 mmol/kg/d). Multivariate logistic regression analysis was performed to identify independent risk factors for stone formation. RESULTS: The prevalence of self-reported nephrolithiasis was 46% (61/132) in hypercalciuric subjects and 11% (7/63) in normocalciuric subjects (P <0.0001). In multivariate analysis, age (odds ratio [OR] per 10 years of age = 1.3; 95% confidence interval [CI]: 1.1 to 1.6), urine calcium excretion (OR = 1.3 per mmol/d increase; 95% CI: 1.2 to 1.5), and uric acid excretion (OR = 3.3 per mmol/d increase; 95% CI: 1.4 to 7.5) were independent risk factors for nephrolithiasis. The risk of nephrolithiasis increased progressively with greater levels of hypercalciuria. CONCLUSION: We found a significant dose-effect association between calciuria and stone disease in patients with familial hypercalciuria. Other factors associated with stone formation included higher uric acid excretion, probably reflecting higher food intake, and age, probably reflecting the length of exposure to hypercalciuria and hyperuricosuria.     

Effect of hyperprotidic diet associated or not with hypercalcic diet on calcium oxalate stone formation in rat

The aim of this study was to determine whether protein, administered alone or simultaneously with a hypercalcic diet, was able to aggravate calcium oxalate stone formation in rats. Thirty-two male Wistar rats were randomly divided into four groups of 8 rats each and assigned a calcium oxalate lithogenic diet added to their drinking water for 3 weeks. One group, used as reference, received a standard diet prepared in our laboratory. The second was assigned the same diet but supplemented with 7.5 g animal proteins/100 g diet. The third received a diet containing 500 mg calcium more than the standard group. The diet given to the last group was supplemented with calcium and protein at the same doses indicated previously. One day before the end of treatment, each animal was placed in a metabolic cage to collect 24-hour urine samples and determine urinary creatinine, urea, calcium, magnesium, phosphate, uric acid, citric acid and oxalate levels. Immediately thereafter, aortic blood was collected to determine the same parameters as in urine. The kidneys were also removed to determine calcium oxalate deposits. Our results showed an increased 24-hour urinary excretion of calcium, oxalate and uric acid and decreased urinary citric acid excretion only in groups that received protein supplementation. At the same time, calcium oxalate deposits were found significantly higher in hyperprotidic diets than reference or calcium-supplemented groups. According to these findings, glomerular filtration, fractional excretion of urea and reabsorption of water, calcium and magnesium were found significantly lower in hyperprotidic diets compared to other groups. These results demonstrate that proteins could seriously aggravate calcium oxalate stones and cause renal disturbances.     

Association of body mass index with serum calcium and phosphate levels

ObjectiveIt has been shown that several environmental and physiological factors can affect on the serum levels of calcium and phosphate. The objective of the present study was explored the relationship between serum calcium and phosphate levels with anthropometric and hematological markers.Methods908 subjects were recruited from the Mashhad stroke and heart atherosclerosis disorder (MASHHAD) program. Anthropometric parameters, liver/kidney function tests (e.g., Urea nitrogen, creatinine, urea and uric acid, creatinine, AST, ALT) were determined in all participants. Serum concentrations of calcium and phosphate were measured using Autoanalyzer BT3000P (Pars Azmoon kit, Tehran, Iran). SPSS software was used for statistical analyses.ResultsWe observed that obese subjects had a lower level of serum calcium (p˂0.05). Moreover, a relationship was detected between serum phosphate level and different menopausal status (p˂0.05). Serum calcium and phosphate did not change by increasing age in the population. Additionally, there was a correlation between lymphocyte count with serum phosphate level (p˂0.05). No statistically different were detected for the levels of calcium/phosphate with respect to smoking status, physical activity, lipid profile, liver and renal function markers.ConclusionWe found an association between serum calcium and BMI as well as with serum phosphate and menopausal status.     

Nephrotoxicity of contrast media in persons over the age of 60

The nephrotoxicity potential and differences of three different contrast media, a high osmolar ionic (Diatrizoate), a low osmolar ionic (Ioxaglate) and a low osmolar non-ionic (Iohexol) after intravenous administration in 84 non-diabetic patients with normal renal function (26 female, 58 male) submitted to digital vascular imaging, were investigated. Forty-five patients (12 female, 33 male) were over 60 years (62–78, mean 66) while 39 patients (14 female, 25 male) less than 60 (36–57, mean 46) years of age. The volume of contrast agent and iodine content were similar in all patients. Serum levels of creatinine, uric acid, β₂-microglobulin, 24 hrs urine content of creatinine, uric acid, β₂-microglobulin and proteins before and 24 hours after contrast medium administration were measured and clearances of creatinine, β₂-microglobulin and uric acid were estimated. No statistical differences were detected in glomerular and tubular function following administration of contrast medium between the two age groups. Based on our results it can be concluded that, in non-diabetic patients with normal renal function over the age of 60 years, the use of low osmolality ionic or non-ionic contrast media will not decrease the nephrotoxicity risk after intravenous administration, and that the seven to ten times higher cost of the newer contrast media (Ioxaglate, Iohexol) should be taken under serious consideration when these agents are considered for use.     

Beta2-microglobulin and cystatin C in type 2 diabetes: assessment of diabetic nephropathy.

BACKGROUND: Changes in glomerular filtration rate (GFR) provide a valuable indicator of the progression of diabetic nephropathy (DN). This study was designed to demonstrate the clinical values of serum cystatin C (Cys C) and beta2-microglobulin in the assessment of renal function in type 2 diabetics by comparing them with the GFR, estimated from the uptake phase of 99 m technetium dimetiltriamino pentaacetic acid renogram (GFR-DTPA) and creatinine clearances. MATERIALS AND METHODS: 68 type 2 diabetic patients with (urinary albumin excretions (UAE) 30 - 300 mg/24 h) (n = 39) and without (UAE < 30 mg/24 h) (n = 29) microalbuminuria and 32 controls were enrolled in the study. Serum Cys C, beta2-microglobulin, creatinine, urinary microalbumin levels, creatinine clearances and GFR-DTPA values were determined in all groups. Non-parametric ROC curves, using a cut-off GFR-DTPA of 60 mL/min/1.73 m (2), were obtained for these markers. RESULTS: Serum Cys C, beta2-microglobulin, glucose and HbA1c concentrations were significantly higher in the group with diabetes compared to controls. In the patients with microalbuminuria, serum Cys C and glucose concentrations increased significantly in comparison to patients with normoalbuminuria, while no differences were observed for beta2-microglobulin levels. Serum creatinine concentrations, GFR-DTPA values and creatinine clearances were not different between both diabetic groups and controls. Cys C was positively correlated with beta2-microglobulin and creatinine and negatively with GFR values; beta2-microglobulin was also positively correlated with serum creatinine in microalbuminurics. A significant inverse correlation was found between beta2-microglobulin and GFR values in both microalbuminurics and normoalbuminurics. CONCLUSIONS: Increased Cys C and beta2-microglobulin in diabetics may be early indicators of incipient DN. The diagnostic accuracies of Cys C and beta2-microglobulin are superior to that of serum creatinine in distinguishing between mild and moderately reduced GFR.     

Effects of hip arthroplasty and peroperative dicloxacillin prophylaxis on renal function.

In a prospective pilot study 70 patients (age greater than 65 years) who underwent hip arthroplasty were treated with dicloxacillin, a total of 6 g given pre-, per- and postoperatively as antibiotic prophylaxis. Creatinine in serum and beta 2-microglobulin in serum and urine were determined as estimates of renal function. Values were obtained preoperatively and on days 2, 4 and 10 after operation. A slight but significant increase of serum creatinine was seen on day 2 with a gradual decrease almost down to the preoperative baseline value on day 10. Serum beta 2-microglobulin increased more gradually; the increase was significant on day 10. Raised levels of beta 2-microglobulin in urine were most pronounced: a 20-fold increase on day 2, then a slow decrease, still significant increase on day 10. This may indicate a reversible damage of proximal tubules with blocked tubular reabsorption of beta 2-microglobulin. The slightly increased levels of serum creatinine and beta 2-microglobulin would also indicate a minor reversible decrease in glomerular filtration rate. Whether these effects are caused by the operation trauma per se or by the dicloxacillin prophylaxis cannot be determined from this pilot study. It seems quite clear that hip arthroplasty with short term prophylaxis with dicloxacillin does not result in clinically important changes in renal function.     

Different Aspects of Kidney Function in Well-Controlled Congenital Hypothyroidism

Objective: Congenital hypothyroidism (CH) increases the prevalence of kidney and urogenital malformations. There are limited studies considering different aspects of kidney function in well-controlled CH patients. We evaluated some features of kidney function in euthyroid children with CH who have been receiving thyroxine hormone since early life.Methods: This cross-sectional study was conducted in Isfahan, Iran, on 74 children aged 2-15 years old (36 CH patients and 38 healthy children). Inclusion criteria for CH patients were euthyroidism at the time of the survey and initiation of replacement therapy during the early neonatal period. Kidney ultrasound evaluation was performed in all participants. Serum biochemistry included urea, creatinine, sodium (Na), potassium (K), magnesium, calcium, and cystatin C levels. Urine electrolytes, fraction excretion (FE) of electrolytes and microalbumin, and glomerular filtration rate (GFR) were also determined.Results: The male/female ratio was 0.8/1 and 1.5/1 in the patient and control groups, respectively. Mean age and height did not differ significantly between the two groups. Ultrasound evaluation of the kidney revealed that the anteroposterior diameter of the right kidney was significantly higher in CH patients as compared to healthy subjects. No significant difference was observed between GFRs in patients with CH and healthy children. The mean values for FENa and FEK were significantly higher in the patient group.Conclusions: Increased FENa and FEK may be a manifestation of impaired tubular maturation in CH. More longitudinal studies are needed to evaluate kidney function in CH patients. Conflict of interest:None declared.     

Effects of dietary protein on urinary calcium in normal subjects and in patients with nephrolithiasis.

The effect of high-protein diets on the excretion of calcium in urine was evaluated in four normal persons and in four patients with nephrolithiasis. All subjects were housed in a metabolic unit and given constant metabolic diets each day containing 0.5 g protein/kg and 300–600 mg calcium, 1000 mg phosphorus, and 69 mEq sodium. During the experimental phase, each person received an additional 1.5 g protein/kg/day consisting of purified casein, gluten, lactalbumin, and gelatin. There was a consistent increase in urinary calcium with the high-protein diet, averaging 88% above control in the normals and 82% in the patients. In addition, the normal subjects showed significant (p < 0.05) increases in urinary phosphorus (mean increases, 219 ± 53 mg/d, mean ± SE), nitrogen (8.8 ± 0.9 g/d), titratable acid (19 ± 5 mEq/d), and ammonium (22 ± 3 mEq/d), whereas the patients showed increases in urinary magnesium (18 ± 2 mg/d), nitrogen (12 ± 1.0 g/d), and ammonium (34 ± 2 mEq/d), and in creatinine clearance (14 ± 3 ml/min). In both groups, there was a small increase in the filtered, excreted, and reabsorbed calcium and a small decrease in the percentage reabsorption of calcium. Serum chemical values did not change from values with the low-protein diet. In two of the patients who were known to be hyperabsorbing calcium, sodium cellulose phosphate (chelator of intestinal calcium) reversed the increase in urinary calcium produced by the high-protein diet. In the remaining patients, neither sodium cellulose phosphate nor a low-calcium diet could counteract the increase in excretion of calcium with the diet. It is concluded that a high-protein diet can increase urinary calcium by altering renal function and/or increasing intestinal absorption of calcium and that dietary protein must be considered in the evaluation and treatment of patients with hypercalciuria and nephrolithiasis.     

The epidemiology of hyperuricemia in children of Taiwan aborigines

OBJECTIVE: To explore the factors influencing serum uric acid concentrations and the prevalence of hyperuricemia in aboriginal children from an area in Taiwan with a high prevalence of gouty arthritis. METHODS: A cross sectional study of the Bunun tribe was conducted in central Taiwan from March to May 2001. Children aged 4-13 were requested to fill out a structured questionnaire with the assistance of their parents. A total of 414 children (mean age, 8.9 +/- 2.1 yrs) were recruited. Uric acid was determined by colorimetry using the uricase method. Since no previous study has investigated serum uric acid concentrations in these aboriginal children, hyperuricemia was defined as uric acid > 416.5 micromol/l (7 mg/dl) in boys and > 357 micromol/l (6 mg/dl) in girls. RESULTS: The mean concentration of serum uric acid was 368.9 +/- 83.3 micro mol/l. Ninety of 224 girls (40.2%) and 56 of 190 boys (29.5%) were hyperuricemic. Children with hyperuricemia had significantly higher body mass index (BMI), blood pressure, and triglyceride and creatinine concentrations than those with normal uric acid concentrations. After adjustment for age, sex, lipid profile, and blood pressure, hyperuricemia was found to be significantly associated with serum creatinine (OR 2.40, 95% CI 1.91-3.04), BMI (OR 1.24, 95% CI 1.11-1.40), and a family history of gouty arthritis in parents (OR 2.01, 95% CI 1.02-3.96). CONCLUSION: BMI, a positive family history of gouty arthritis in parents, and creatinine level correlated with hyperuricemia in aboriginal children in Taiwan.     

Renal function in patients with urinary stones of varying compositions

Kidney stones are a potential risk factor for chronic kidney disease. The impact of different urinary stone components on renal function is unknown. In this study, we retrospectively reviewed 1,918 medical records of patients with urolithiasis. The renal function was evaluated as estimated glomerular filtration rate. All the stones were analyzed by Fourier transform infrared spectroscopy. The patients were divided into five groups according to the stone components. Statistical analysis was performed with analysis of variance. All the patients with stones had Stage 2-3 chronic kidney disease. The patients with uric acid and struvite stones had significantly lower estimated glomerular filtration rate compared with those having other stone components (p<0.01). Furthermore, the patients with calcium-containing stones (calcium oxalate and calcium phosphate) had significantly better renal function than those with non-calcium-containing stones (struvite and uric acid, p<0.01). Patients with urolithiasis had decreased renal function, and the impact of renal function varied depending on the stone components. We conclude that stone analysis is important in predicting the change in renal function in patients with urolithiasis. Moreover, the patients with non-calcium-containing stones, such as struvite and uric acid stones, should be carefully evaluated and treated to preserve their renal function.     

Urinastatin (Kunitz-type proteinase inhibitor) reducing cisplatin nephrotoxicity

The authors investigated the reductive effects of a Kunitz-type proteinase inhibitor, urinastatin, on the nephrotoxicity seen in lung cancer patients treated with cisplatin by measuring N-acetyl-beta-D-glucosaminidase (NAG) activity and beta 2-microglobulin (BMG) content in 24 hour urine, creatinine clearance, blood urea nitrogen (BUN), serum creatinine, uric acid, and BMG as factors of nephrotoxicity. In control patients treated with anticancer drugs containing cisplatin but no supplemental urinastatin, the 24 hour urine NAG and BMG levels increased more than three-fold over the pretreatment levels, 3 days after anticancer therapy, respectively. Creatinine clearance significantly decreased and levels of BUN, serum uric acid, and BMG in control patients significantly increased over the corresponding pretreatment levels, 3 days after anticancer therapy. However, supplemental urinastatin reduced abnormalities in levels of all these factors 3 days after therapy. These results suggest that supplemental urinastatin protects from cisplatin-induced nephrotoxicity, especially proximal tubular damage.     

南宁地区复杂性肾结石的红外光谱结石成分分析

目的了解南宁地区复杂性肾结石的成分,为其治疗及预防提供依据。方法回顾分析98例南宁地区复杂性肾结石的红外光谱结石成分及相关临床资料。结果 93例（94.9%）为含钙混合性结石和感染性结石,其中一水草酸钙结石2例（2.0%）,一水草酸钙和碳酸磷灰石结石20例（20.4%）,一水草酸钙、二水草酸钙和碳酸磷灰石结石16例（16.3%）,一水草酸钙和无水尿酸结石12例（12.2%）,一水草酸钙、碳酸磷灰石和无水尿酸结石13例（13.3%）,一水草酸钙、六水磷酸镁铵和碳酸磷灰石结石9例（9.2%）,一水草酸钙、二水草酸钙、六水磷酸镁铵和碳酸磷灰石结石8例（8.2%）,六水磷酸镁铵和碳酸磷灰石结石13例（13.3%）。单一无水尿酸结石5例（5.1%）。结论南宁地区复杂性肾结石绝大多数以草酸钙为主的混合性或感染性结石,碳酸磷灰石、尿酸和磷酸镁铵是其常见的混合成分。体积较大的复杂性肾结石成分复杂,生长过程中常多种病因参与,应加强其病因诊断和针对多种病因采用积极的预防性治疗。     

Theophylline-induced alteration in serum electrolytes and uric Acid of asthmatic children

Theophylline, (1,3-dimethylxanthine) is widely used as a smooth muscle relaxant, myocardial stimulant and a diuretic agent. The most frequent use of theophylline is in treatment of acute and chronic asthma as a bronchodilator. To determine the effect of Theophylline on serum electrolyte and uric acid, 21 asthmatic children (age range 1.5-7 years) with severe acute asthma and 25 patients with chronic asthma (5-15 years ) who were being treated with slow-release theophylline were enrolled in this study. Fifty age and sex matched normal children took part as control. Blood samples (5m1) were withdrawn before, during and after completion of the course of intravenous theophylline treatment (0.05-0.70 mg/kg/ hr). Sera obtained were used for analysis of K+, Na+, phosphorus, calcium and uric acid by RA-1000 automated analyzer and the following results were obtained: (1) After treatment, total serum calcium in acute asthmatic patients decreased significantly compared with controls (P<0.01); (2) serum phosphate and K+ levels of acute and chronic asthmatic patients after therapy decreased as compared with controls (P<0.01). (3) Post therapy increase in serum level of uric acid in acute and chronic asthmatic patients was statistically significant as compared with control (P<0.001). We conclude that the serum levels of phosphate, potassium, calcium and uric acid should he monitored in patient receiving theophylline especially during prolonged use and critical emergency cases.     

Prognostic significance of the serum phosphorus level and its relationship with other prognostic factors in multiple myeloma

We studied the serum phosphorus (P) level of 110 patients with multiple myeloma (MM) (age range 42–83 years, median 62 years) and evaluated the relationship between that and other prognostic factors. Serum P level significantly correlated with the prognostic factors that are relevant to renal dysfunction: serum creatinine (P<0.00000001), serum β2-microglobulin (P=0.00000088), serum uric acid (P=0.0000014), and corrected serum calcium (cCa P=0.000067). Although it also correlated with the percentage of plasma cells in bone marrow nucleated cells (BMPC%) and the hemoglobin (Hb) and leukocyte counts, the significance was less than for the other four prognostic factors. Serum creatinine, BMPC%, leukocyte count, serum uric acid, bone lesions, β2-microglobulin, and serum cCa were all significantly higher and Hb significantly was lower in the MM patients with hyperphosphatemia (serum P>3.8 mg/dl). The survival time was significantly shorter in these patients (P=0.000087). Multivariate analysis (Cox’s proportional hazards regression model) showed that the serum P level is a significant negative prognostic factor in MM patients.