Hyperammonemia during total parenteral nutrition in children

Serial blood ammonia (NH3) determinations in 19 low birth weight (LBW) infants, 14 term neonates and 12 children receiving total parenteral nutrition (TPN) have shown that 73% of patients had one or more elevated NH3 values (greater than 150 micrograms/dl). The mean blood NH3 was 220 +/- 13 micrograms/dl in LBW infants, 180 +/- 9 micrograms/dl in 10 infants, and 140 +/- 7 micrograms/dl in children. All of these values are significantly higher than normal (p less than 0.001). There was no difference in incidence or mean blood ammonia concentration between patients receiving casein hydrolysate and those receiving a crystalline amino acid solution. Only four patients were symptomatic and several infants remained fully alert despite blood NH3 concentration in excess of 400 micrograms/dl. One infant who had sustained hyperammonemia was given another amino acid source (Travasol) containing 1.2 mmol/dl of arginine; blood NH3 promptly fell to the normal range. However, six of seven additional infants had hyperammonemia while receiving Travasol (mean = 184 micrograms/dl). Hyperammonemia is common during TPN in children, often is not recognized clinically, and occurs with equal frequency in infants and older children. The high levels observed in LBW infants may be due to hepatic immaturity. Blood NH3 concentration should be monitored frequently during TPN. Persistent hyperammonemia should be treated by decreasing protein content of the infusate. The role of supplemental arginine is unclear.     

Vitamin E status of patients receiving long-term parenteral nutrition: is vitamin E supplementation adequate?

Vitamin E status of eight patients receiving total parenteral nutrition (TPN), including 10 IU of all-racemic alpha-tocopheryl acetate daily and Intralipid 20% (500 mL; 12 mg of RRR-alpha- and 92 mg of RRR-gamma-tocopherols) two to three times per week for 69 +/- 45 (mean +/- SD) months was assessed by measuring plasma and adipose tissue tocopherol concentrations. Plasma alpha-tocopherols of TPN patients were similar to controls (17.5 +/- 6.6 mumol/L vs 22.4 +/- 5.1), whereas gamma-tocopherols were significantly reduced (6.0 +/- 3.1 vs 11.2 +/- 3.6, p less than 0.03). The adipose tissue alpha- and gamma-tocopherol/triglycerides (TG) were similar (369 +/- 215 nmol/mmol vs 452 +/- 228, and 125 +/- 102 vs 140 +/- 130, respectively), but cholesterol/TG were increased in the TPN patients (7.8 +/- 2.5 mumol/mmol vs 5.1 +/- 3.5, p less than 0.05), suggesting that adipose tissue was relatively TG-depleted and tocopherol/cholesterol measurements better reflect vitamin E status. The mean alpha-tocopherol/cholesterol ratios were significantly lower in the TPN patients than the controls (55 +/- 36 vs 106 +/- 63, p less than 0.04). Thus, current vitamin E supplementation of TPN patients seems insufficient for maintenance of adequate tissue stores.     

Low serum selenium and glutathione peroxidase activity in patients receiving short-term total parenteral nutrition

Selenium status was determined in 15 consecutive postoperative patients receiving short-term total parenteral nutrition (TPN) using both serum selenium concentration and glutathione peroxidase (GSH-Px) activity as an indicator of body selenium status. The serum selenium concentration was significantly (p less than 0.001) lower in TPN patients (0.52 +/- 0.16 mumol/l, mean +/- SD) than in age- and sex-matched controls (1.08 +/- 0.17 mumol/l). Serum selenium in TPN patients ranged from 0.28 to 0.79 mumol/l and was associated with the duration of TPN. The lowest selenium values was found in patients who had received TPN over 3 weeks (0.35 +/- 0.06 mumol/l) as compared to patients receiving TPN for 1-3 weeks (0.61 +/- 0.13 mumol/l; p less than 0.01). Serum GSH-Px activity in TPN patients was also low (116 +/- 21 U/l) and ranged from 75 to 159 U/l. A significant positive correlation was found between serum selenium and GSH-Px activity (r = 0.520; p less than 0.05) whereas serum selenium and GSH-Px activity did not correlate significantly with liver function tests and body mass index. This study suggests that also short-term TPN patients may be at risk of selenium deficiency.     

Zinc tolerance test in uremia: effect of calcitriol supplementation

The effect of 1,25(OH)2D3 on zinc absorption was indirectly determined in hemodialysis patients using the oral zinc tolerance test. The increment in plasma zinc and the area under the curve following an oral zinc load of 25 mg were studied in seven patients, before and after 6 weeks of therapy with 1 microgram/day of 1,25(OH)2D3 [Rocaltrol(R)]. Before therapy, fasting plasma zinc, 2 hour plasma zinc, and the area under the curve (AUC) were subnormal (hemodialysis patients vs normals: 96 +/- 2 vs 105 +/- 3 micrograms/dl, p less than 0.05, 161 +/- 8 vs 222 +/- 16 micrograms/dl, p less than 0.025, and 188 +/- 25 vs 302 +/- 33 micrograms hr/dl, p less than 0.025, respectively). Following Rocaltrol, serum calcium level increased (8.9 +/- .12 to 9.8 +/- .4 mg/dl, p less than 0.05), parathyroid hormone levels decreased (20.4 +/- 8.9 to 13.6 +/- 7.2 ng/ml, p less than 0.05), but there was no significant change in fasting plasma zinc, 2 hour plasma zinc, or AUC (89 +/- 3 micrograms/dl, 149 micrograms/dl, and 176 +/- 18 micrograms hr/dl, respectively). These results suggest that short-term 1,25(OH)2D3 therapy had no significant impact on zinc absorption or plasma zinc level in uremics.     

Food consumption patterns of Canadian preschool children in relation to zinc and growth status

Hair and serum zinc and copper, growth percentiles, and dietary intakes, based on 3-day weighed food records, were determined for 106 Canadian preschool children (62 M, 44 F) aged 4-5 yr. Mean (+/- SD) hair zinc levels were (M) 103 +/- 35 micrograms/g vs (F) 129 +/- 34 micrograms/g, p less than 0.001, and median hair copper level was 12.4 micrograms/g (M + F). Mean serum zinc and copper were 111 +/- 13 micrograms/dL (M + F) and 122 +/- 21 micrograms/dL (M + F), respectively. Males with low hair zinc (less than 70 micrograms/g) had a lower mean height-for-age percentile (42 +/- 29 vs 58 +/- 25%, p less than 0.05), even when adjusted for midparent height. Males with hair zinc less than 70 micrograms/g and/or height-for-age less than 15% consumed less meat, poultry, and fish and received similar average zinc intakes but higher calcium intakes than males with hair zinc greater than or equal to 70 micrograms/g and/or height-for-age greater than or equal to 15%. Suboptimal zinc nutriture was associated with lower intakes of readily available zinc from flesh foods and higher intakes of calcium.     

Blood mononuclear cell magnesium in normal pregnancy and preeclampsia

Magnesium (Mg) is effective in the treatment of pregnancy-induced hypertension (PIH). In order to determine if patients with PIH are Mg deficient, we assessed mononuclear cell magnesium content (mMg) and serum Mg concentrations (sMg) in 23 normal pregnant women and in 12 women with PIH admitted in active labor. The sMg concentration in women with PIH was 1.74 +/- 0.1 mg/dl (mean +/- SD) and was not significantly different from normal pregnant women at 1.69 +/- 0.2 mg/dl. Both groups had sMg concentrations lower than in normal, non-pregnant controls (sMg = 1.96 +/- 0.1 mg/dl, p less than 0.001). The mMg content in normal pregnant women did not differ significantly from that in women with PIH (1.54 +/- 0.26 micrograms Mg/mg protein and 1.50 +/- 0.26 micrograms Mg/mg protein respectively). The normal control mean mMg was 1.36 +/- 0.17 micrograms Mg/mg protein, slightly lower than in normal pregnancy (p less than 0.005) and PIH (p less than 0.02). Mononuclear Mg content did not correlate with sMg concentration. These data suggest that PIH is not associated with an intracellular Mg deficit. Further studies utilizing other measures of intracellular Mg are indicated to assess the presence or absence of Mg deficiency in patients with both normal pregnancy and pregnancy complicated by PIH.     

Plasma ammonia levels in preterm infants receiving parenteral nutrition with crystalline L-amino acids

In order to investigate the severity and incidence of hyperammonemia in preterm infants receiving total parenteral nutrition (TPN) with crystalline L-amino acids having high arginine content (Travasol), we determined the plasma ammonia (PA) levels in a group of 29 preterm infants on TPN, weekly and 1 wk posttherapy. Their mean gestational age was 29.9 +/- 2.6 wk and mean birth weight 1208 +/- 262 g. Thirty five blood samples obtained from 15 preterm infants not on TPN with mean gestational age 32.2 +/- 1.9 wk and a birth weight of 1495 +/- 161 g served as a control. In the parenteral nutrition group the mean PA level (140 +/- 58 micrograms/100 ml) was significantly higher (p less than 0.001) than that in the same group one week post TPN (97 +/- 34 micrograms/100 ml) and in the control group (86 +/- 35 micrograms/100 ml). The incidence of hyperammonemia (greater than 160 micrograms/100 ml) was 30% in the TPN group versus 3% in the controls (p less than 0.01). Maximal PA level during that treatment was 405 versus 216 micrograms/100 ml 1 wk post-TPN versus 163 micrograms/100 ml in the controls. The data show a significant increase in PA levels in preterm infants receiving TPN with Travasol, possibly because of its high glycine content.     

Zinc supplementation during pregnancy: zinc concentration of serum and hair from low-income women of Mexican descent

The effect of zinc supplementation on concentrations of zinc in hair and serum of 213 pregnant Hispanic women attending a clinic in Los Angeles was assessed using a random, double-blind experiment. Both the treatment (T) and control (C) groups received similar vitamin and mineral supplements except that 20 mg zinc was added to the supplements for the treatment group. Nutrient intakes were calculated from 24-h recalls. The initial mean dietary zinc intake of both groups was about 50% of the Recommended Dietary Allowance (9 +/- 5 mg). Initially there were no significant differences between the two groups in mean zinc levels in serum (66 +/- 11 micrograms/dl, C, and 65 +/- 12 micrograms/dl, T) or in hair (184 +/- 41 micrograms/g, C, and 175 +/- 38 micrograms/g, T). Zinc supplementation did not alter mean zinc levels in serum or hair but significantly (p less than 0.05) reduced the number of low serum zinc values (less than or equal to 53.3 micrograms/dl) toward the end of pregnancy. Although serum zinc levels do decline in pregnancy, our results suggest that severely depressed levels (less than or equal to 50 to 55 micrograms/dl) indicate inadequate zinc status.     

Tissue storage of vitamins A and E in rats drinking or infused with total parenteral nutrition solutions

The total parenteral nutrition (TPN) rat and its sham-operated control were used as a model to compare the metabolism and storage of vitamins A and E when they are administered intravenously or orally. Male Fisher rats were depleted of both vitamins for several months with a diet free of vitamins A or E, but containing retinoic acid for growth. TPN solutions containing aqueous dispersions of retinol, retinyl palmitate and dl-alpha-tocopheryl acetate were infused at 2.3 ml/h into the jugular veins of 10 TPN rats. Eight sham-operated control rats drank similar volumes from food cups. TPN rats received 115.3 +/- 4.5 (mean +/- SEM) micrograms of retinol equivalents and 2.2 +/- 0.2 mg of alpha-tocopherol equivalents per day; controls received 146.4 +/- 16.5 micrograms and 2.1 +/- 0.3 mg, respectively. After 7 days the animals were fasted overnight and killed. Plasma levels of retinol were 27.8 +/- 1.5 micrograms/dl for TPN rats, and 27.4 +/- 1.2 for controls. Plasma alpha-tocopherol was 1909 +/- 183 micrograms/dl for TPN rats and 1063 +/- 77 for controls. The only forms of the vitamins found in plasma after overnight fasting were unesterified retinol and unesterified alpha-tocopherol. Sham-operated control rats stored amounts of vitamins A and E similar to values reported in the literature for fed animals. TPN rats stored more of both vitamins than controls in liver, heart, and spleen, but not in testes. The enhanced liver vitamin storage by TPN rats did not appear to be due to a slight increase in lipid content. The results indicate that both vitamins A and E infused in TPN solutions maintain blood levels and are stored in tissues.     

Hepatic abnormalities associated with aluminum loading in piglets

Cholestasis is a common complication of total parenteral nutrition (TPN) in infants. A contributing factor to the hepatic dysfunction may be a contaminant of the TPN solution, such as aluminum, that accumulates in liver and may act as a hepatotoxin. To study the hepatic effects of aluminum, growing piglets were given daily intravenous injections of aluminum, 1.5 mg/kg, for 50 days; pair-fed controls were given heparinized saline. At sacrifice, liver and serum were obtained. Liver was analyzed for histopathology and for aluminum content and localization. The hepatocyte lysosomes of the experimental group showed aluminum peaks by x-ray microanalysis, whereas the control group did not. No differences in ultrastructure were noted between the two groups when examined by electron microscopy. Mean serum total bile acid levels (27.8 +/- 15.9 SD vs 6.3 +/- 1.5 mumol/liter, p less than 0.05), mean alkaline phosphatase (309 +/- 108 vs 180 +/- 27 IU/liter, p = NS), and mean hepatic copper content (24.8 +/- 4.5 vs 14.4 +/- micrograms/g dry weight, p less than 0.01), were elevated in the aluminum-loaded piglets, indicating that cholestasis may have been produced. Also, a small but significant reduction in serum levels of 25 hydroxy-vitamin D was found in the aluminum-loaded piglets, suggesting that vitamin D hydroxylation may be impaired. Inasmuch as lysosomal contents are excreted into the bile, aluminum accumulation in lysosomes may alter lysosomal function and possibly affect bile flow or content.     

Vitamin A deficiency in pre-school age Congolese children during malarial attacks. Part 2: Impact of parasitic disease on vitamin A status

The vitamin A status of 454 pre-school age Congolese children was evaluated by the impression cytology method with transfer (ICT) and by the determination of plasma retinol. During malarial attacks, the vitamin A status is abnormal (deficient or marginal) in 40.8% of the children according to the ICT test and in 37.5% of the children who have plasma levels of retinol lower than 10 micrograms/dl. The mean concentration of plasma retinol in patients during malarial attacks (14.8 +/- 9.5 micrograms/dl) is significantly lower than the values found in other subjects (31.5 +/- 14.3 micrograms/dl) (p less than 0.001). A significant correlation was established between the results of the ICT test and two biochemical parameters (retinol, transthyretin). We conclude that there is a significant relationship between vitamin A deficiency and a malarial attack.     

Parenteral nutrition in bone marrow transplantation

Twenty-nine patients undergoing bone marrow transplantation (BMT) were randomised prospectively to evaluate the effect of parenteral nutrition (TPN) on morbidity and mortality. Fourteen patients received a standard regimen of TPN for 10 +/- 4 days (mean +/- SD). All patients had free access to oral diet, which was significantly reduced compared to pre-transplant intake. In the TPN group, serum bilirubin by day 14 and serum bilirubin and gamma glutamyl transferase by day 21 were significantly higher than in the controls (p < 0.05). These differences probably reflect the higher incidence of serious pyrexia (T > 38.5' C) and blood culture positive rates in the TPN group. Weight loss in the control group was significantly greater than that of the TPN group (p < 0.05). TPN did not affect time to grafting or incidence of graft-versus-host disease. The use of TPN in the nutritional support of patients in small BMT units requires careful consideration.     

Zinc supplementation during pregnancy in low-income teenagers of Mexican descent: effects on selected blood constituents and on progress and outcome of pregnancy

As a follow-up of our study of pregnant women, we report effects of zinc supplementation during pregnancy in another population of 138 Hispanic teenagers in Los Angeles. Teenagers were randomized (double-blind) to a control or zinc-supplemented group and received similar daily vitamin and mineral supplements except for 20 mg zinc added to the zinc-supplemented group's capsules. Initially, mean dietary zinc intakes of both groups were about 50% of the Recommended Dietary Allowance and their mean serum zinc levels did not differ significantly (69.8 +/- 11.2 micrograms/dl in control and 69.0 +/- 11.4 micrograms/dl in zinc-supplemented group). Zinc supplementation did not maintain mean serum zinc levels during pregnancy but, as in our earlier study, it reduced (p = 0.018) the number of low serum zinc values (less than or equal to 53 micrograms/dl) in late pregnancy. Zinc supplementation did not affect outcome of pregnancy but serum zinc levels were lower (p = 0.038) in teenagers with pregnancy-induced hypertension than in normotensives.     

Total parenteral nutrition in severe acute pancreatitis

The influence of total parenteral nutrition (TPN) was studied in 67 patients with severe acute pancreatitis having three or more criteria according to Ranson (mean +/- SD = 3.8 +/- 0.21). Although TPN has been reported to not be of benefit in the progress and severity of the disease, we have found that the time TPN is started is important in influencing the course of the disease and in the development of local complications, as well as in the mortality rate. Patients whose TPN was started within the first 72 hours of the disease had a 23.6% complication rate and 13% mortality, in comparison with patients whose TPN was started later in the course of the disease, who had a 95.6% complication rate (p less than 0.01) and a mortality rate of 38% (p less than 0.03). The nutritional status of the patients during TPN administration of 28.4 days was maintained either steady or was improved, as assessed by nitrogen balance, serum levels of transferrin (p less than 0.05), and albumin (p less than 0.05). The administration of fat solution, either to prevent essential fatty acid deficiency or to provide part of the caloric requirements, was found to cause neither clinical nor laboratory worsening of the disease. All pancreatic fistulae that developed during the course of the disease spontaneously closed in patients receiving TPN without operation in a mean period of 33.3 days, and all pseudocysts subsided in an average of 18.3 days. Those who died (overall mortality rate 24%) had had uncontrollable sepsis, which resulted in hypercatabolism and multiple system organ failure.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum lipoproteins in home total parenteral nutrition patients

Patients maintained in our home total parenteral nutrition (HTPN) program receive very small amounts of cholesterol in their solutions. Because of the severe intestinal insufficiency which is characteristic of this group, they do not absorb significant amounts of cholesterol or bile salts from their intestines. We investigated the serum lipoproteins in nine patients maintained on HTPN for 36 +/- 4 (mean +/- SEM) months. Fat emulsions were given twice a week as a source of essential fatty acids. Mean serum cholesterol 110 +/- 6.5 mg/dl, LDL-cholesterol 75 +/- 6 mg/dl, and HDL-cholesterol 29 +/- 1 mg/dl, were at or below the 5th percentile compared with age- and sex-matched Lipid Research Clinic controls. HDL-cholesterol to serum cholesterol ratio was in the normal range (0.25 +/- 0.30). The mean serum cholesterol did not rise, but the mean serum triglyceride rose significantly from 72 +/- 4 to 104 +/- 16 mg/dl (p less than 0.05) immediately after completion of TPN infusions with fat emulsions. There was a negative correlation between the length of HTPN therapy and the total serum cholesterol (r = 0.43, p less than 0.05). Thus, HTPN patients have markedly depressed concentrations of total serum cholesterol, LDL-cholesterol, and HDL-cholesterol, but the ratio of HDL cholesterol to total serum cholesterol is in the normal range.     

Plasma and red blood cell vitamin E status of patients on total parenteral nutrition

Plasma and red blood cell (RBC) tocopherol isomer (alpha, beta, delta, and gamma) concentrations were measured prior to, and following total parenteral nutrition (TPN), with Intralipid. Before feeding, nine of 13 patients had plasma total tocopherol levels less than 0.6 mg/dl (normal range 0.63-1.24 mg/dl) and 10 of 13 had total RBC tocopherol levels less than 0.2 mg/dl (normal range (0.20-0.39 mg/dl). Following 7 days TPN plasma vitamin E status increased significantly (p less than 0.001). However, this was due mostly to increases in the circulating level of beta + gamma-tocopherols. RBC vitamin E status was also significantly increased (p less than 0.001) following TPN, however, this was again due to incorporation of non-alpha-tocopherols. In a second study a alpha-tocopherol supplement, Vitlipid N, (9.1 mg alpha-tocopherol/day) was included in the feed. In these patients, large increases in plasma concentrations of non-alpha-tocopherol isomers were accompanied by an apparent improvement in alpha-tocopherol status (0.64 vs 0.44 mg/dl after 7 days). However, RBC alpha-tocopherol concentration did not change appreciably in these patients following either 7 or 14 days feeding. It is concluded that RBC vitamin E status is markedly influenced by the available plasma tocopherol pool and that provision of a small supplement of alpha-tocopherol is not sufficient to compete with the high concentration of non-alpha-isomers present in Intralipid. TPN utilizing fat emulsions containing high levels of non-alpha-tocopherol isomers (even when accompanied by alpha-tocopherol supplements) does not improve alpha-tocopherol status.     

Effects of smoking and drinking habits and vitamin A intake on serum concentrations of beta-carotene and retinol]

Serum samples from 341 males aged 10 to 59 years were obtained and stored at -40 degrees C until examined for retinol and beta-carotene concentrations by HPLC, and their relationships to smoking habit, alcohol drinking habit and vitamin A intake were studied. In univariate analysis the serum beta-carotene level was significantly lower in the smokers than in the non-smokers (smokers: 4.6 micrograms/dl, non-smokers: 7.1 micrograms/dl, p less than 0.01) and lower in the drinkers than in the non-drinkers (drinkers: 4.6 micrograms/dl, non-drinkers: 7.3 micrograms/dl, p less than 0.01). The serum retinol level was not different by smoking habit but was higher in the drinkers than in the non-drinkers (drinkers: 80.4 micrograms/dl, non-drinkers: 67.0 micrograms/dl, p less than 0.01). Serum beta-carotene was higher in the group with a greater intake of vitamin A of vegetable origin (6.1 micrograms/dl) than in the group with a smaller intake of it (4.7 micrograms/dl) (p less than 0.01), but serum retinol was not different by the amount of vitamin A intake of animal food origin. To estimate the respective effects and interactions of the above factors on serum beta-carotene and retinol levels by adjusting for the confounding effects of age, serum total cholesterol, HDL-cholesterol and triglyceride, analysis of covariance was performed. For serum beta-carotene, smoking habit (p less than 0.01), drinking habit (p less than 0.01) and the amount of vitamin A intake of vegetable food origin (p less than 0.05) had significant main effects.(ABSTRACT TRUNCATED AT 250 WORDS)     

Magnesium status in children with insulin-dependent diabetes mellitus

We assessed the magnesium status in 67 children with insulin-dependent diabetes mellitus (IDDM) in various degrees of diabetic control and its changes during the evolution of the disease. This was done by measuring fasting serum magnesium and 24-hr urinary magnesium clearances when patients were first studied, as well as subsequently on follow-up. In 23 of these patients the retention of intramuscular magnesium was also assessed in relation to the degree of diabetic control and the duration of the illness. The mean +/- SD serum magnesium levels were significantly lower in diabetic children as compared to nondiabetic controls (1.91 +/- 0.22 vs 2.12 +/- 0.26 mg/dl, p less than 0.001). Serum magnesium in diabetic children correlated with glycosylated hemoglobins (r = -0.358, p less than 0.001), but not with 24-hr glycosuria (r = -0.296). On follow-up of patients, serum magnesium significantly increased when IDDM control improved and decreased when the control worsened. Diabetic patients had increased urinary magnesium clearances compared to nondiabetic subjects (5.26 +/- 3.58 vs 3.60 +/- 1.36 cc/min, p less than 0.05). All but five of the 23 patients given the magnesium load retained more than 40% of the dose, with a mean +/- SD retention of 58.7 +/- 5.1%. There was no correlation between the amount of retained magnesium and the duration of the illness, degree of diabetic control, amount of glycosuria, magnesuria, magnesemia, glycosylated hemoglobins, or serum lipids. The data confirm that lower than control serum magnesium levels occur frequently among children with poorly controlled IDDM. Moreover, there might be magnesium deficiency in IDDM, as indicated by the high retention of magnesium when given intramuscularly. The deficiency of this ion may or may not be accompanied by decreased serum magnesium levels and may result from increased urinary magnesium losses in children with IDDM.     

Biological monitoring of lead exposure in high risk groups in Berat, Albania

STUDY OBJECTIVE: To determine blood lead concentrations in children living in an area with a battery plant in Berat, Albania. Another aim was to determine blood lead concentrations in mothers and cord blood levels in neonates from Berat and compare them with values found in Tirana. DESIGN: Cross sectional survey with a 10% random sample of children, and a 10% sample of mothers and newborn. SETTING: Hospitals, schools, and kinder-gartens in Berat and Tirana, Albania PARTICIPANTS: 129 preschool children, 373 school children, 151 mothers and their newborn. MAIN RESULTS: The mean observed blood lead concentrations in 84 preschool children living less than 2 km from the battery plant was 43.4 micrograms/dl (SD 23.0) and significantly higher than in 45 preschool children (mean 15.0 micrograms/dl, SD 3.5) living more than 2 km from the plant. Mean lead concentrations in 145 school children living close to the plant were 26.6 micrograms/dl (SD 14.4) compared with 16.0 micrograms/dl in 228 school children living at a greater distance. In 67% of the preschool children and 41% of the school children lead levels exceeded the WHO borderline level of 20 micrograms/dl, and 98% of preschool children, and 82% of school children had values greater than 10 micrograms/dl. Mean lead concentrations in cord blood of 151 newborn was 8.9 micrograms/dl (median 8.8, range 4.9-20.0 micrograms/dl), and 10.6 micrograms/dl in blood of their mothers (median 10.0, range 5.0-25.4 micrograms/dl). Mean lead concentrations in Tirana were 8.9 (newborn), and 7.0 micrograms/dl (mothers). CONCLUSIONS: Blood lead concentrations in children from Berat are comparatively high and abatement measures are needed.

 

     

Body burdens of lead in hypertensive nephropathy

Chronic lead exposure resulting in blood lead concentrations that exceed 1.93 mumol/l (40 micrograms/dl) or chelatable urinary lead excretion greater than 3.14 mumol (650 micrograms) per 72 h has been associated with renal disease. A previous study had found greater chelatable urine lead excretion in subjects with hypertension and renal failure than in controls with renal failure due to other causes, although mean blood lead concentrations averaged 0.92 mumol/l (19 micrograms/dl). To determine if chelatable urinary lead, blood lead, or the hematologic effect of lead (zinc protoporphyrin) were greater in hypertensive nephropathy (when hypertension precedes elevation of serum creatinine) than in other forms of mild renal failure, we compared 40 study subjects with hypertensive nephropathy to 24 controls having a similar degree of renal dysfunction due to causes other than hypertension. Lead burdens were similar in both the study and control groups as assessed by 72-h chelatable urinary lead excretion after intramuscular injection of calcium disodium EDTA (0.74 +/- 0.63 vs. 0.61 +/- 0.40 mumol per 72 h, respectively), and by blood lead (0.35 +/- 0.23 vs. 0.35 +/- 0.20 mumol/l). We conclude that subjects from a general population with hypertensive nephropathy do not have greater body burdens of lead than renal failure controls.