Hyperzincaemia and hypercalprotectinaemia: a new disorder of zinc metabolism.

BACKGROUND: Calprotectin (complex of S100A8 and S100A9) is the major calcium and zinc-binding protein of phagocytes. We report a new syndrome with recurrent infections, inflammation, and hyperzincaemia associated with excessively high plasma concentrations of calprotectin. METHODS: We measured calprotectin in plasma and protein fractions by ELISA assay and zinc by atomic absorption spectrometry. Plasma proteins were fractionated by size exclusion chromatography and electrophoresis. Mass spectra of purified proteins were determined by MALDI-TOFMS. FINDINGS: We assessed five patients, two of whom are related. All patients had much the same biochemical findings of hyperzincaemia (77-200 micromol/L, reference range 11-18 micromol/L) and raised plasma calprotectin concentrations (1.4-6.5 g/L, reference range <1 mg/L). All patients presented with recurrent infections, hepatosplenomegaly, anaemia, and evidence of systemic inflammation. Three patients had cutaneous inflammation and three presented in infancy with severe growth failure. Size exclusion chromatography showed that zinc and calprotectin were associated in a broad fraction with molecular weight range 100-300 kDa. Analysis by electrophoresis and mass spectrometry showed that the patients' protein contained normal S100A8 and S100A9 subunits. INTERPRETATION: Dysregulation of zinc metabolism associated with accumulation in plasma of S100A8 and S100A9 defines a new disease, which encompasses a pathological role for dysregulation of two members of the large S100 protein family.

Hyperzincemia with systemic inflammation: a heritable disorder of calprotectin metabolism with rheumatic manifestations?

A boy had infantile-onset systemic inflammation, growth failure, hepatosplenomegaly, anemia, leukocytopenia, progressive muscular dystrophy, and hypercalprotectinemia, resulting in marked hyperzincemia. His mother had a history of chronic arthritis since childhood and also showed hypercalprotectinemia/hyperzincemia. We postulate an inherent defect in calprotectin metabolism.

Effect of zinc on lean tissue synthesis during recovery from malnutrition

During recovery from severe wasting, malnourished children gain weight at greatly accelerated rates. To determine if additional zinc added to their basal therapeutic diets increased the retention of lean tissue and stimulated protein metabolism, we studied three groups of children taking either the basal diet alone or the basal diet supplemented with either 76 mumol (5 mg) or 153 mumol (10 mg) Zn/kg diet. The zinc-supplemented children gained similar weight and consumed the same amount of diet as the unsupplemented children. Zinc supplementation resulted in a greater net absorption of nitrogen and a higher rate of protein turnover, as estimated from urinary ammonia 15N enrichment after oral [15N] glycine. We conclude that additional zinc affected the composition of newly synthesized tissue and intermediary nitrogen metabolism (AU)

Zinc intake and plasma insulin-like growth factor-I (IGF-I) in Jamaican malnourished children - abstract

The effect of zinc intake on plasma immunoreactive insulin-like growth factor-I (IR-IGF-1) was studied in 24 children (aged 3 to 24 mos) recovering from severe malnutrition. The children were randomly assigned to two groups for zinc supplementation. Twelve (Zn+) were given (2mg/kg/d) added to the recovery of diet, and 12 (ZN-) were not. There was no group difference in age, sex, anthropometric measurements or plasma IR-IGF-1 at baseline. Plasma IR-IGF-1 was significantly higher in the zinc supplemented children during recovery (p = 0.031). These results suggest that zinc intake stimulates IR-IGF-1 production. (AU)

Electron microscopy of herpes simplex hepatitis with hepatocyte pulmonary embolization in kwashiorkor

We report a case of herpes simplex hepatitis in a child with edematous malnutrition. Electron microscopy showed virus in parenchymal cells. With pulmonary embolization of necrotic, infected hepatic cell fragments. Systemic dissemination of herpes simplex may be related both to the profound immunoincompetence associated with kwashiorkor and to a reduction in the circulating and fixed polyanions that normally inhibit viral attachment to cells.(AU)

Relationships among dietary quality, children's appetites, growth stunting and efficiency of growth in poor populations

Monotonous diets prevail among the poor in developing countries. In Jamaica, small children do not eat a variety of foods and the foods they do eat has a low energy density and is low in protein. Further, infants receive sweetened maize meal porridge and infant formula in a bottle. Older children eat a thicker porridge and rarely eat meats. Yet these children are content with small infrequent feedings. They often have infections which further diminishes their appetite resulting in weight loss. Their weight often does not catch up between infections. Gaseous intestinal distention, foul feces, and anorexia (indicative of small bowel anaerobic overgrowth) are common symptoms of undernutrition. Further anorexia is also a symptom of zinc, potassium, and phosphorous deficiencies. 17 percent of children <5 years old in Jamaica weighed <80 percent of the NCHS standard for age. Among 11-17 year old boys, the height of low income boys in Jamaica was much shorter (by 9 cm) than that of middle income Jamaican boys and the NCHS standards. This shows that earlier, chronic, environmental stress results in stunting. Further childhood undernutrition can also impair mental development. Food supplements do not always result in weight or height gain, however. Yet essential minerals and vitamins are not included in food supplements, but are included in animal feed. Lean tissues and adipose tissue synthesis are needed for normal growth each of which requires different diets. An optimal balance of amino acids and essential elements known as type II nutrients (potassium, magnesium, calcium, phosphorus, and zinc) are needed for lean tissue synthesis while adipose tissue synthesis needs energy for storage. Jamaican children who quickly improve after malnutrition become fat indicating that muscle synthesis lags behind adipose tissue synthesis. In conclusion, to prevent growth failure, nutritionists should concentrate on nutrient balance and nutrient intake in the diets and supplements of children.(AU)

The glomerulus in kwashiorkor - abstract

The pathogenesis of the oedema of kwashiorkor is unknown. We therefore examined by electron microscopy the kidneys of seven children who had died from oedematous malnutrition. There was effacement of the glomerular epithelial cells onto the basement membrane in each case. The picture was thus similar to that seen in minimal-change nephrotic syndrome. Current concepts relate glomerular retention of proteins to the anionic charge on the basement membrane; glomerular effacement is thought to be the expression of loss of this charge; however, none of the children had clinical albuminuria. Albumin excretion rate was therefore measured, using a fluoro-immunoassay, with a sensitivity of 1mg/1, in 24hr urine collections from children on admission, after a full course of gentamicin and at clinical recovery. There was no increase in urinary excretion (microalbuminuria) in the oedematous or the marasmic children. There was no difference in the microalbuminuria of the children who died and those who recovered. Microalbuminuria was not present after a full course of gentamicin. To investigate whether the glomerular abnormality was indeed due to a change in the charge on the basement membrane we perfused the kidneys of a child who had died from oedematous malnutrition with the sulphated polyanion heparin, immediately after death. The heparin corrected the effacement of the glomerular epithelial cells. We conclude that the foot process effacement is due to a reduction in the anionic charge of the glomerular basement membrane in oedematous malnutrition, that the membrane charge may be restored by circulating polyanions such as heparin and that, unlike other conditions associated with glomerular epithelial cell effacement, this defect in kwashiorkor is not associated with albuminuria. The charge may be more easily neutralised by cations such a gentamicin. However, gentamicin does not lead to microalbuminuria, which would be expected if there were significant glomerular or tubular damage. An alteration of the negative charge on the body's proteoglycans may affect the water holding capacity of the tissues and be related to the development of oedema (AU)

Vitamin E status in oedematous and non-oedematous malnourished children - abstract

The antioxidant function of vitamin E is essential for maintaining the integrity of cell membranes. During the early phase of recovery from severe malnutrition, we measured the plasma levels of Vitamin E in 58 children on admission (A), and after metabolic recovery (B). A total of 19 marasmic children, and 34 with oedematous malnutrition (19 with marasmic-kwashiorkor and 15 with kwashiorkor) were studied. A further group of 5 oedematous children who were clinically assessed as extremely sick received daily vitamin E supplements. The children were all fed on the same dietary regimen. The results indicated that although vitamin E intake was greater in the non-oedematous (marasmic) children, the rate of change of concentration in the plasma did not differ between the two groups. This could possibly be attributed to a difference in the absorption or utilization of the vitamin between the groups. In the group receiving supplements, there was a significant increase in plasma vitamin E concentration between A and B. However, the rate of increase and the concentration at B did not differ from that in the two groups of unsupplemented children. We conclude that in malnourished children: (1) plasma viatmin E levels are low on admission, (2) values normalize by time B, and (3) supplementation with alpha-tocopherol in oil did not affect the rate of increase in plasma vitamin E. The supplement did not seem to be bioavailable (AU)

The relationship between red cell glutathione and hepatic steatosis in malnourished Jamaican children - abstract

Low levels of red cell glutathione (a scavenger of free radicals) have been previously shown to correlate well with the presence of oedema in malnourished children. We addressed the possibility that they may also correlate with the extent of hepatic steatosis. Thirty-three children were studied on three occasions - on admission, in early weight gain and at discharge. Ultrasonography was used to assess hepatic fat. The oedematous children had significantly more hepatic fat on admission than the non-oedmatous (p<0.01), but no child had a normal ultrasound. We found a significant inverse relationship (r = -0.53, p<0.001) between hepatic fat and the level of red cell glutathione that disappeared over time. We conclude that, firstly, hepatic steatosis occurs commmonly in even non-oedematous malnourished children. Secondly, this is associated with low levels of glutathione which may have aetiological implications (AU)

Plasma iron, transferrin and transferrin saturation of severely malnourished Jamaican children - abstract

Mortality amongst severely malnourished children is often associated with an unusually high hepatic store of iron (Fe). Indeed, this excess Fe has been implicated in the aetiology of kwashiorkor. In order to examine the possibility that unbound Fe may be present in the plasma of malnourished Jamaican children, Fe and its transport protein, transferrin were measured. Transferrin saturation ( percentTS) was calculated from plasma Fe and transferrin levels. The measurements were also carried out in a control group of 23 healthy children who had presented for elective minor surgery. Plasma Fe levels (fg/dl) in children with marasmic-kwashiorkor (MK; n = 59. 69ñmeanñ), kwashiorkor (K, n = 37; 76ñ) and in those who died (D;n = 24: 111ñ) were not significantly different from the control group (C; 79ñ). In the marasmic group Fe levels (M;n = 63: 66ñ g/dl) were significantly lower than (p<0.05) than normal. In malnutrition, transferrin levels (mg/dl) were significantly lower (p<0.001) than normal: C - 232ñM - 170ñn = 66: MK - 110ñn = 61: K - 84ñn = 41: D - 77ñn = 24. In the marasmic group transferrin levels were significantly higher (p<0.001) than the other malnourished groups. percentTS was lowest in the marasmic group and highest in the group of children who died. At a percentTS of 30 percent, mortality was 5 per cent compared with a mortality of 24 per cent when percentTS was >90 per cent. It is concluded that oedematous malnourished Jamaican children have normal plasma levels of iron, but significantly reduced levels of circulating transferrin. The latter were more severely decreased in children with kwashiorkor and those who died. Elevated percentTS was associated with increased mortality. It is recommended that iron supplements be witheld during the early stages of resuscitation of the malnourished child (AU)

Zinc and muscle growth during recovery from malnutrition - abstract

During recovery from severe malnutrition, muscle gain is slow relative to overall weight gain. We postulated that this might be due to an inadequate supply of zinc. We therefore compared nitrogen (N) balance and protein synthesis rates (as estimates of muscle gain) during early, mid and late recovery in children fed 3 different levels of dietary zinc (Low Zn gp.n = 4; Moderate Zn gp.n = 4; High Zn gp.n = 3). N intake was similar in the 3 Zn groups throughout recovery. N net absorption and N retention were also similar in early recovery. Later, both increased in the moderate and high Zn groups only: so also did the N retention /g wt gained. By late recovery, they were each significantly higher in the high Zn gp than in the low Zn gp. Thus, Zn supplementation of the relatively low Zn recovery diet resulted in synthesis of tissue richer in N - and therefore, by implication, having a higher proportion of muscle. Protein synthesis rates were calculated from the 15N enrichments of urinary urea and ammonia at plateau, obtained during a constant nasogastric infusion of 15N labeled glycine. Overall, the results using the 2 different end products were not different. However, there was a difference among the Zn gps in the 15N ammonia enrichments. From these values, protein synthesis rates were significantly higher than in the high Zn gp than in the low Zn gp by late recovery (table included). These data are consistent with the N balance data in that they indicate increased muscle protein metabolism with Zn supplementation (AU)

Plasma zinc levels throughout pregnancy: a study in Jamaican women with relevant aspects of nutrition - abstract

In a prospective study, plasma zinc levels were determined by atomic absorption spectrophotometry in 135 Jamaican women over a two-year period. A total of 1,237 such determinations were made at fixed intervals throughout pregnancy. Zinc being an essential trace element with a wide physiological role in many aspects of metabolism, supplementary studies on the relationship between zinc, folic acid, vitamin A and dietary intake in general were undertaken. Results (Table) show that plasma zinc levels were lowered during pregnancy, moreso during the second trimester: the levels rise significantly during labour and then fall rapidly towards normal during the puerperium. Daily dietary zinc intake was of the order of 8-10 mg/day (the RDA for pregnancy being 15 mg/day) while protein intake averaged 67 gm/day (the RDA for protein being 80-90 gm/day). Clinical and laboratory investigations revealed no signs of any dietary deficiency among the patients. Average weight gain in pregnancy was 12 kg. Plasma, vitamin A and red cell folate levels were within normal ranges in all patients, indicating that there was no state of zinc deficiency interfering with the absorption of these vitamins. Viewed together, all the facts of this study suggest that the pattern of the fall of plasma zinc in pregnancy is a normal physiological change not related to socio-economic status, parity or age. It is concluded that the lowered plasma zinc observed in pregnancy does not reflect a state of true deficiency nor even a state of inadequate dietary zinc intake; it is most likely due to the heavy demand for zinc in the developing foetal tissues and by the expanding maternal blood volume (AU)

The use of eggs in the assessment of selenium status of a community - abstract

Selenium (Se) deficiency appears to play a part in the development of oedematous malnutrition. It occurs in regions where soil Se availability is low. This is likely in wet, tropical limestone-based regions, such as in much of Jamaica. In high Se regions in Venezuela, Se status of the inhabitants and Se concentrations in the locally produced eggs were high. The present study explored the potential use of egg Se concentrations as a monitor for low Se areas in Jamaica. Six areas were selected, three of which were expected to be low Se areas. Homes were visited and free range hens' eggs, soil samples and hair samples were collected. Se concentrations of the sample were measured. For each area, the mean concentrations in ppm dry weight were: Glengoffe, Haynes, E. St. Thomas, Porus, Mavis Bank, Lluidas Vale; YOLK - 1.3, 2.1, 2.2, 1.8, 1.2, 1.6 respectively Total mean is 1.8; WHITE - 1.5, 3.0, 4.4, 2.4, 1.6, 2.1 Total mean is 2.7; SOIL - 0.7, 0.6, 1.1, 1.8, 0.4, 1.9 respectively Total mean is 1.2; HAIR - 0.5, 0.6, 0.6, 0.8, 0.5, 0.5 respectively Total mean is 0.6. In many of the soil samples, the values found were lower than the accepted normal range. However, in egg and hair samples, they were mostly within the normal (literature) range. There were no very low values. There was a linear correlation between egg white and egg yolk concentrations (n=101, r=0.84, p<0.001) and between egg yolk and soil concentration (n=102, r=0.20, p<0.05). Overall, however, egg Se concentration did not reflect closely either soil or hair Se concentration, and therefore is unlikely to be a useful index of Se status of a community (AU)

Zinc absorption in malnutrition - abstract

Malnourished children are often zinc-deficient. Net intestinal absorption (NA) of zinc is the main factor controlling zinc status: NA = TA - ES, where TA is total intestinal absorption, and ES is endogenous secretion of zinc into the intestine. In order to investigate factors affecting zinc homeostasis, we have measured NA and TA in 7 severely malnourished and in 10 recovered (weight-for-height) children, 8 to 18-months-old. NA was calculated as the difference between feed zinc intake and faecal zinc output over a 3-day period. TA was calculated as the difference between feed intake and faecal output of the stable isotope, 70Zn, given over the first 6 hours of the balance. Eight of the recovered children, the control group, were given a standard cow's milk-based infant formula at 'maintenance energy' intake. TA of zinc was 25ñ7 percent of zinc intake (meanñSD); it increased significantly with the age and weight of the child, and insignificantly with the weight gain (RWG). NA of zinc, 19ñ8 percent of zinc intake, was not related to age, weight or RWG. ES of zinc varied from 0 to 22 percent of zinc intake. The other 2 recovered children were given a low protein formula, also at 'maintenance energy' intake. Of them, 4 non-oedematous children had RWG similar to the recovered children but NA of zinc (8ñ4 percent of intake) was lower than in the recovered children. TA (32ñ1 percent of intake) was lower than in the 2 recovered children on the same formula. The 3 oedematous children were sicker than the others; two were anorectic and therefore fed by nasogastric tube throughout their balances. TA were 5 and 9 percent in the tube fed and 21 percent in the other child. NA of zinc was -28, +2 and -14 percent. Thus 2 children had a high ES of zinc while the other child had a low ES Zn; he was the only one with profuse diarrhoea. The very low TA Zn and negative NA in two of the three children show that zinc homeostasis was markedly deranged and that zinc deficiency was probably present. This is consistent with our previous finding of low plasma zincs in oedematous malnourished children. The findings imply the need for zinc supplementation of severely malnourished children, in particular those with oedema. They also imply that factors affecting zinc absorption include the child's age and/or weight, and the dietary zinc and/or protein content. This study was supported by the Medical Research Council and the Wellcome Trust (AU)

Selenium status during recovery from malnutrition: effects of selenium supplementation - abstract

It was previously shown that malnourished Jamaican children often had evidence of selenium deficiency, viz. low erythrocyte glutathione peroxidase (RBC GSH Px) activity that correlated inversely with cardiothoracic ratio, and was particularly low in children who died. In this study, RBC GSH Px activity, plasma GSH Px activity and plasma selenium concentration were measured in 41 malnourished children on admission to hospital, and after recovery in weight-for-height. Plasma GSH Px activity and selenium concentrations were also measured longitudinally throughout recovery in a group of 24 initially selenium-deficient children, 17 of whom were given oral selenium supplements for the first 3 weeks. RBC GSH Px activity was low in all malnourished children, whether oedematous or not (Table). It did not change with recovery. Plasma GSH Px activity and plasma selenium concentration were low only in oedematous malnourished children. PEM GROUPS: control, marasmus, oedematous; ERYTHROCYTE GSH Px (U/gHb)- *36ñ2, 24ñ4, 21ñ3 respectively; PLASMA GSH Px act. (U/L) - 140ñ9, 142ñ15, 98ñ8 respectively, PLASMA SE CONCN. (æg/e) - 86ñ4, 76ñ12, 53ñ5. *meanñSEM. Selenium was associated with a rapid rise in both plasma GSH Px activity and plasma selenium concentration. The increase in plasma selenium was more dramatic (44 up to 144 æg/e in 6 days): the variability in plasma GSH Px activity was much greater, and they remained within the control range. The changes were sustained after supplementation ceased. We conclude that (1) selenium deficiency in malnourished Jamaican children is not reversed during 'recovery' on the conventional 'high energy' diet, (2) plasma selenium concentration responds rapidly to changes in selenium intake, and is a useful measure of selenium status, and (3) oral selenium supplements improve selenium status in children recovering from malnutrition (AU)

Erythrocyte clutathione reductase activity and riboflavin status in severely malnourished children - abstract

Erythrocyte glutathione reductase (EGR), cofactor is riboflavin (vit B2), functions together with glucose 6-phosphate dehydrogenase to maintain cellular levels of glutathione and thus the integrity of the erythrocyte. The compromised antioxidant status of severely malnourished children along with increased exposure to metabolic stress led us to postulate that EGR activity might be increased in malnutrition as a compensatory response to oxidative stress. We therefore measured EGR activity in 49 severly malnourished children on admission and again in 35 of these children at discharge. Erythocyte glutathione-reductase-activation-coefficient (ERGAC), an index of riboflavin status, was also assessed. Twenty-two healthy children served as controls (C). The malnourished group had significantly higher EGR activity (8.34 ñ 0.31 U/g Hb; mean ñ SEM) than the control group (6.63 ñ 0.23 U/g Hb). On admission, children with marasmus (M) had significantly higher EGR activities (8.95 ñ .046 U/g Hb) than children with marasmic kwashiorkor (MK: 8.08 ñ 0.67 U/g Hb) or kwashiorkor (K: 7.66 ñ 0.53 U/g Hb). At discharge, high levels of EGR were maintained in all groups. However, the kwashiorkor group showed a significant increase up to (10.37 + 0.41 U/g Hb). An EGRAC > 1.30 indicates riboflavin deficiency. Forty per cent of the controls as well as 50 percent of the malnourished children were deficient in riboflavin supplementation of the malnourished groups, the EGRAC fell to normal levels. We concluded (1) that EGR activity is increased in severly malnourished children; this may be as a result of increased metabolic stress, and (2) the riboflavine status of malnourished children improved significantly during their recovery (AU)