Hemoglobin level is linked to growth hormone-dependent proteins in short children

Erythropoiesis was investigated in 32 children wih short stature and in eight children with skeletal dysplasia by studying blood hemoglobin in relation to growth and to serum concentrations of insulin-like growth factor I (IGF-I), IGF binding protein-3 (IGFBP-3), and erythropoietin (EPO) before, during, and after 12 months of recombinant human growth hormone (GH) treatment. Blood hemoglobin concentration was positively correlated with relative body height and with serum IGF-I and IGFBP-3 levels (P = .001 to .02), but not with the concentrations of EPO. The normal age-dependency of hemoglobin was lacking. Hemoglobin levels and their responses to GH treatment were similar in the patients with GH deficiency and those with normal GH secretion. Treatment with GH accelerated growth and elevated the concentrations of hemoglobin, IGF-I, and IGFBP-3. In the eight patients with skeletal dysplasia, body mass increased similarly, but gain in height was less than in the other patients, and the increase in hemoglobin was markedly pronounced. In this group, the correlations between hemoglobin, IGF-I, and IGFBP-3 were extremely close (r = 0.80 to 0.85, P = .031 to .008). These findings are in accord with earlier observations from in vitro and animal studies, and suggest that the GH-IGF axis is involved in the physiologic elevation of hemoglobin levels during childhood.

Serum transferrin and ferritin in pubertal boys: relations to body growth, pubertal stage, erythropoiesis, and iron deficiency

We studied serum transferrin and ferritin concentrations in relation to individual body growth, stage of puberty, blood hemoglobin, and red blood cell iron (RBCI) in 60 prepubertal or early pubertal boys at 3-mo intervals for 18 mo. One-third of the boys had increased serum transferrin concentrations and almost all had decreased ferritin concentrations during the followup. No change in mean transferrin was observed but the individual 18-mo increments in transferrin correlated positively with the increments in hemoglobin (r = 0.55, P < 0.001) and in estimated RBCI (r = 0.31, P = 0.02). Serum transferrin remained stable at different genital stages, but ferritin was lower in the pubertal than in the prepubertal boys. Transferrin concentrations at 18 mo correlated positively with the preceding weight velocities. The rise in transferrin did not lead to an increase in iron-deficiency anemia. In contrast, transferrin rose in boys whose hemoglobin increased. In pubertal boys with relatively ample iron status, serum transferrin may be an indicator of increased availability of iron for erythropoiesis. The declining ferritin concentration indicates that part of the extra iron is mobilized through redistribution from stores to red blood cell mass and is generally associated with greatly increasing absorption. Thus, the pubertal changes in transferrin and ferritin are not necessarily indications of iron deficiency.

Sensitive immunoassay and in vitro bioassay demonstrate constant bioactive/immunoreactive ratio of luteinizing hormone in healthy boys during the pubertal maturation

The quality of serum LH was assessed during pubertal maturation in boys by measuring immunoreactive (I) LH by a time-resolved immunofluorometric assay (IFMA, Delfia), and bioactive (B) LH by a sensitized in vitro bioassay. Seven samples were collected at 3-mo intervals from 14 healthy boys (median starting age 11.8 y) during pubertal maturation from Tanner stage I-III or II-IV (n = 7 for each). The mouse Leydig cell in vitro bioassay was sensitized 10-fold, to 0.05-0.1 IU/L, by including 1.5 mumol/L of forskolin in the incubation medium. The I- and B-LH levels showed good linear correlation throughout the concentration range analyzed. Mean I-LH increased between the pubertal stages I-IV from 0.42 to 2.24 IU/L and that of B-LH from 1.35 to 5.04 IU/L. No concomitant change occurred in the B-LH/I-LH (B/I) ratio, which was 2.84 +/- 0.54 in stage I and 2.58 +/- 0.48 in stage IV (mean +/- SEM, n = 7). Although the B/I ratios of LH varied from 0.59 to 5.85 in the samples analyzed, the intraindividual variation was small (mean coefficient of variance, 22%). In conclusion, IFMA and sensitized in vitro bioassay showed in healthy boys a similar 4-5-fold increase in the mean LH concentration during pubertal maturation, with no concomitant change in the B/I ratio. The sensitized in vitro bioassay of LH is useful for analysis of the low peripubertal LH levels. The good correlation between the I-LH and B-LH levels, and the lack of change in LH B/I ratio, indicate that IFMA correctly estimates the LH levels upon evaluation of pubertal maturation.

Myocardial function in children and adolescents after therapy with anthracyclines and chest irradiation

Cardiotoxicity is a potential adverse effect of anthracycline (A) therapy. Radiotherapy (XRT) may also cause a variety of cardiac complications. The purpose of the present study was to evaluate these cardiac side-effects in children and adolescents treated for cancer. We assessed the cardiac status of 91 patients, divided into three groups: Group A (n = 53) had anthracyclines at a mean cumulative dose of 410 mg/m2, group A+XRT (n = 26) had both chest irradiation (XRT) and A (mean 360 mg/m2), and group XRT (n = 12) had XRT alone. The patients differed from the controls in both systolic and diastolic indices of myocardial function. In echocardiography, the left ventricular (LV) contractility was abnormal in 32% in group A, in 50% in group A+XRT, and in 8% in group XRT. In radionuclide cineangiography, the LV ejection fraction was subnormal in 19% in group A, in 24% in group A+XRT, and in 1 patient in group XRT. A higher cumulative dose of A predicted decreased contractility. Treatment with A and/or XRT often leads to cardiotoxicity. Although in most cases this cardiotoxicity seems to be mild and subclinical, the long-term clinical sequelae merit further evaluation.

Peripheral blood cell counts in infants with Down's syndrome

The current literature indicates that several abnormalities have been observed in the three hematopoietic cell lines of infants with Down's syndrome. This prospective, longitudinal study was designed to clarify the physiological variation in peripheral blood cell values of children with Down's syndrome by following 25 such infants during their first year of life. Apart from polycythemia in the first week of life, the hemoglobin concentration was, in general, the same as in normal term infants. At 9-12 months of age values for mean corpuscular hemoglobin and mean corpuscular volume tended to be elevated. Serum erythropoietin concentrations were low to normal. White blood cell counts were slightly lower in children with Down's syndrome than in normal children. The study infants had profound thrombocytosis from the age of 6 weeks to the end of follow-up at 1 year. This study, the first longitudinal follow-up of such subjects, indicates that infants with Down's syndrome often have evidence of polycythemia soon after birth and red blood cell macrocytosis and thrombocytosis later in infancy. In conclusion, we carried out peripheral blood cell counts in 25 infants with Down's syndrome, but with no actual hematological disturbance, during their first year of life, and compared them with values for normal term infants.

Circulating transferrin receptor during erythropoietin medication of anemic patients with rheumatoid arthritis

Serum levels of the transferrin receptor (TfR) were monitored in 12 anemic patients with rheumatoid arthritis (RA) undergoing treatment with recombinant human erythropoietin (rHuEPO) for a 24-week period. Measurement of TfR was performed using an enzyme immunoassay. Compared to a mean pretreatment level of 4.2 mg/l (range 2.1-6.1 mg/l), there was an increase in the mean TfR concentrations from 2 weeks of treatment onwards to a maximum of 7.7 mg/l (range 2.1-12.3 mg/l) at 12 weeks (p < 0.01). Nine of the 12 patients responded to rHuEPO with an increase in blood hemoglobin concentration of 15 g/l or more. An increase in TfR levels was documented not only in the responders but also in the 3 nonresponders. We conclude that in anemic RA patients exogenous erythropoietin induces a swift and sustained increase in the serum concentration of TfR, which probably reflects increased expression of TfR on erythroblasts. This sustained elevation of TfR seems to occur even in patients who do not have an increase in their hemoglobin level.

Vitamin B-6 status during childhood: tracking from 2 months to 11 years of age

To examine the development and tracking of long-term vitamin B-6 status from infancy to early adolescence, measurements of erythrocyte pyridoxal 5'-phosphate concentration (EPLP), the erythrocyte aspartate transaminase (EAST) stimulation test including measurements of basal activity (EASTo) and activation coefficient (alpha EAST), were made in a follow-up study of healthy children aged 2 (n = 139), 4 (n = 147), 6 (n = 157), 9 (n = 159) and 12 mo (n = 188) and 5 y (n = 148). The EAST stimulation test was repeated at 11 y (n = 153). Vitamin B-6 status, high during infancy, reached the adult level by 5 y of age. The 10th to 90th percentile ranges for EPLP values were 61-201 nmol/L at 4 mo, 49-101 nmol/L at 12 mo and 27-59 nmol/L at 5 y. The respective ranges for Easto were 16-24 microkat/L at 4 mo, 13-19 microkat/L at 12 mo, 9-14 microkat/L at 5 y and 25-39 microkat/L at 11 y of age. For alpha EAST values were 1.29-1.54 at 4 mo, 1.48-1.77 at 12 mo, 1.70-2.07 at 5 y and 2.00-2.57 at 11 y. Values for EPLP and the EAST stimulation test in the first year of life correlated with the values at 5 and 11 y. The individuals with values at the extreme ends of the distributions remained there from infancy to childhood up to 3.3 times more often than expected from random variation.(ABSTRACT TRUNCATED AT 250 WORDS)

Outcome after first relapse in children with acute lymphoblastic leukemia: a population-based study of 315 patients from the Nordic Society of Pediatric Hematology and Oncology (NOPHO)

This study reports the outcome after relapse of acute lymphoblastic leukemia (ALL) in a population-based study of 809 children over 1 year of age diagnosed July 1981 through June 1986 and with non-B acute lymphoblastic leukemia in the five Nordic countries. By January 1994, 315 children had suffered at least one relapse. The bone marrow was involved in 216 cases. There were 69 isolated CNS relapses, 25 isolated testicular recurrences and five relapses in other extramedullary sites. Of the 315 children with relapse, 94 are still in a second complete remission 12-138 (median: 78) months after relapse. The overall probability of a second event free survival (P-2.EFS) and survival after relapse was 0.28 and 0.33 respectively. The probability of remaining in second remission at 11 years was significantly correlated to the duration of first remission (P < 0.001), the site of relapse (P < 0.001) and gender (P = 0.004). The P-2.EFS for early, intermediate, and late bone marrow involved relapses were 0.08, 0.19, and 0.50 respectively. For early, intermediate and late isolated CNS relapses the P-2.EFS were 0.21, 0.38 and 0.61, respectively. The P-2.EFS for boys with isolated testicular relapses was 0.69. Girls with isolated CNS relapse (P < 0.001) and with bone marrow involved relapse (P = 0.04) had a significantly better prognosis than boys. Children with initial high risk criteria, especially T-ALL and mediastinal mass who relapsed, had a very poor prognosis.

CONCLUSION

In this population-based study, about 30% of children with ALL obtained a long second remission and possible cure.

Impaired response to hepatitis B vaccine in children receiving anticancer chemotherapy

Serologic responses to hepatitis B vaccine were investigated in 197 pediatric cancer patients. The patients, ages 1 to 21 years, comprised 66 with solid tumors, 101 with hematologic malignancies and 30 with various benign conditions. Of them 51 were receiving cytotoxic chemotherapy and 114 had not received chemotherapy for 0.2 to 11 years. Three doses of plasma-derived hepatitis B vaccine (20 micrograms) were given at 0, 1 and 6 months; and antibody concentrations to hepatitis B surface antigen were determined at 3, 6 and 8 months. The geometric mean antibody concentration after 3 vaccine doses was 1076 mIU/ml in cancer patients receiving chemotherapy and 18,833 mIU/ml in cancer patients not receiving chemotherapy. The protective titer of antibody (> or = 10 mIU/ml) was reached after 3 doses of vaccine by 67% of patients receiving chemotherapy and by 97% of those not receiving chemotherapy. The patients being treated for solid tumors had weaker responses than those being treated for hematologic malignancies: after 3 vaccine doses no response was observed in 6 of 11 patients with solid tumors compared with 3 of 25 of patients with hematologic malignancies. Children receiving anticancer chemotherapy have essentially weaker responses to hepatitis B vaccine than children not receiving chemotherapy or those with benign conditions. This reflects the profound immunosuppression during chemotherapy. The effect of more intensive immunization schedules should be investigated.

Tumor markers CA 125 and CA 19-9 in cord blood and during infancy: developmental changes and use in pediatric germ cell tumors

Tumor markers CA 125 and CA 19-9 are elevated in a variety of malignancies in adult patients, but only little is known of their biology during gestation or infancy. We have addressed the developmental pattern of these carbohydrate antigens in pediatric patients by measuring their serum levels in 133 cord blood samples from the second through third trimester of gestation and in 39 infants aged less than 1.5 y. The serum concentrations of both markers revealed developmental changes, the levels being higher at earlier gestation (wk 24 through 37) than at term or during infancy. The clinical value of the markers was evaluated by monitoring 26 children with germ cell tumors; 14 benign and 2 immature teratomas, and 11 malignant germ cell tumors. Patients with immature sacrococcygeal teratomas showed constant and prolonged elevations of serum CA 125 and CA 19-9. In contrast, all but two children with mature teratomas had normal marker levels; these two patients with abnormally high serum CA 125 and CA 19-9 values for the first 4 postoperative weeks had a benign ovarian and ventricular teratoma, respectively. Of the 11 children with malignant germ cell tumors, serum CA 125 or CA 19-9 concentration was elevated in four patients at diagnosis and declined to normal within 2 wk after institution of therapy. Malignant recurrence in two patients was not associated with a reelevation of the CA 125 level. Taken together, our results demonstrate a developmentally regulated pattern of serum CA 125 and CA 19-9. The carbohydrate markers were usually inferior to alpha-fetoprotein in monitoring of germ cell tumors, but may be a useful adjunct in the follow-up of immature teratomas.

Low vitamin B6 status associated with slow growth in healthy breast-fed infants

To evaluate the effect of vitamin B6 status on infant growth, we studied longitudinally anthropometry and the erythrocyte parameters that reflect long-term vitamin B6 status [erythrocyte pyridoxal 5'-phosphate concentration (EPLP), erythrocyte aspartate transaminase basal activity (EAST0), and its activation co-efficient (alpha EAST)] in 44 infants. The infants were exclusively breast-fed for 6 mo, given additional solids according a uniform schedule from 6-9 mo, and formula after 9 mo, if needed. In seven of these infants, a low vitamin B6 status (EPLP < 10th, and EAST0 > 10th or alpha EAST > 90th percentile for these values in reference infants) was observed between 4 and 6 mo of age. These seven infants showed slower length velocity (0.30 +/- 0.05 versus 0.40 +/- 0.02 mm/d, p < or = 0.02) and deeper fall in length-for-age (-0.69 +/- 0.20 versus -0.25 +/- 0.07 SD score, p < or = 0.03) from 6 to 9 mo of age than the similarly fed infants with higher vitamin B6 status. Preceding vitamin B6 status remained a significant explanatory factor for length velocity and change in length-for-age in addition to preceding and concomitant weight velocity, when sex, birth size, preceding length gain, and mid-parent height were taken into account. Change in weight-for-age alone explained 16% and 18% and, together with vitamin B6 status, 23 and 27% of the variation in length velocity and in change in length-for-age, respectively. Thus, in healthy breast-fed infants, according to our results, low vitamin B6 status is associated with reversibly reduced gain in length.

Sitostanol ester margarine in dietary treatment of children with familial hypercholesterolemia

In familial hypercholesterolemia (FH) the lowering of serum cholesterol levels should be started in childhood in order to prevent coronary artery disease later in life. However, treatment of children is problematic. We studied the effects of sitostanol (3 g/day) ester dissolved in rapeseed oil margarine as a hypocholesterolemic agent in one homozygous and 14 heterozygous children with FH maintained on a low cholesterol diet for 6 weeks, using a double-blind crossover design. Absorption and synthesis of cholesterol were evaluated by measuring serum plant sterol and cholesterol precursor proportions to cholesterol by gas-liquid chromatography. The compliance was good, and the children could not distinguish by taste the two margarines without and with sitostanol ester. Sitostanol margarine significantly reduced serum total, intermediate density (IDL), and low density lipoprotein (LDL) cholesterol by 11, 26, and 15%, respectively, and increased HDL/LDL cholesterol ratio by 27%. The proportions of serum delta 8-cholestenol, lathosterol, and desmosterol were significantly increased by 36, 19, and 18%, and those of serum cholestanol, campesterol, and sitosterol were significantly decreased by 9, 42 and 29%, respectively, suggesting that cholesterol absorption was decreased and synthesis was compensatorily increased. High basal precursor sterol proportions predicted a high decrease in LDL cholesterol levels. In conclusion, partial replacement of normal dietary fat consumption by sitostanol ester margarine appears to be an effective and safe hypocholesterolemic treatment in children with FH.

Allogeneic bone marrow transplantation in children: single institution experience from 1974 to 1992

At the Children's Hospital, University of Helsinki, Finland, bone marrow transplantations have been performed since 1974. Between 1974 and 1992, 62 children received allogeneic bone marrow grafts. Median patient age was 9.3 years. Thirty-two patients had ALL, 13 AML and 11 had severe aplastic anemia (SAA). Graft failure occurred in 4 of the 62 patients. The overall long-term survival rate was 47%. Relapse of leukemia was the most common cause of death, especially in patients with ALL transplanted in second or later remission. Deaths during the first 2 months after transplant have decreased with time. In a small country such as Finland, it is important to centralize the experience of allogeneic BMTs, particularly for pediatric patients.

Testicular function in adult males surviving childhood malignancy

Testicular function was studied in 109 males aged 16 to 25 years surviving leukemia or solid tumors in childhood. The mean follow-up time was 10.3 years after diagnosis. Of the patients studied, 18 had received testicular radiotherapy, 35 central nervous system radiotherapy, and 3 total body radiotherapy. Twenty-one patients presented with incomplete puberty and 85 presented with small testicles (< 20 mL). Of the 109 patients, 43 had elevated concentrations of serum follicle-stimulating hormone (FSH) or serum FSH and leutinizing hormone. Compared with survivors of solid tumors, the patients surviving acute lymphoblastic leukemia (ALL) had inferior testicular status. This was also the case even when those treated with testicular radiotherapy were excluded. Twenty-six patients were receiving testosterone substitution therapy at the time of the study; 25 of whom were survivors of ALL. The probability of normospermia was 50% if both testicular volume and serum FSH were within normal limits and 0% if they were abnormal. Of the 86 patients over 18 years of age, 16 had evidence of normal testicular function. Of these 16, 8 patients had normospermia, only 1 of whom was a survivor of ALL. These findings suggest that ALL survivors have inferior testicular function compared with patients surviving solid tumors. Our findings confirm that testicular radiotherapy inevitably results in testicular damage, the degree of which is generally severe but variable in some individuals. We were unable to find an explanation for the individual tolerance to therapy, eg, age at diagnosis.

Cardiopulmonary evaluation of exercise tolerance after chest irradiation and anticancer chemotherapy in children and adolescents

OBJECTIVE

The aim of the study was to evaluate the cardiopulmonary exercise tolerance in children and adolescents after chest irradiation and anticancer chemotherapy.

METHODS

We studied 30 subjectively asymptomatic patients aged 8 to 25 years treated for pediatric malignancies with chest irradiation (XRT) +/- chemotherapy. The median interval since XRT was 7 (range, 2 to 13) years. The median XRT dose for mediastinum and/or lungs was 2550 (range, 1000 to 5100) cGy. The median cumulative dose of anthracyclines was 250 (range, 0 to 480) mg/m2. Cardiac function and exercise tolerance were evaluated by electrocardiography, echocardiography, radionuclide cineangiography, and exercise test with gas exchange analysis.

RESULTS

The patients differed from normal controls in systolic indices of myocardial function. In echocardiography, the left ventricular contractility was abnormal in 14/30 patients. In radionuclide cineangiography, the left ventricular ejection fraction was subnormal in 6/30 patients, and in 9/30 patients the rise in ejection fraction during exercise was inadequate (< 5%). In exercise testing, the mean (+/- SD) maximum workload attained was 2.7 (+/- 0.7) watts/kg, and the mean (+/- SD) maximum oxygen consumption was 35.4 (+/- 9.7) mL/min/kg. Both variables were < 80% of predicted values in 11 patients.

CONCLUSIONS

XRT and anticancer chemotherapy very often lead to late cardiopulmonary toxicity and impaired exercise tolerance. Although in most cases this toxicity seemed to be mild and subclinical, the long-term clinical sequels merit further evaluation.

Bleeding and use of blood products after heart operations in infants

Recent studies have suggested that postoperative bleeding is decreased in pediatric heart operations if fresh whole blood instead of blood component therapy is used for postoperative transfusions. Because this is in contrast to our practice to use whole blood for only the priming of the cardiopulmonary bypass circuit and then to use blood components for additional transfusion requirements, it was our interest to analyze the bleeding complications and the use of blood products after heart operations in infants. The patient records of the 73 infants operated on in 1992 were reviewed. The chest tube drainage varied from 3 to 51 ml/kg per 6 hours (mean 10 ml/kg) and it did not correlate with any of the tested clinical or laboratory parameters. One infant underwent reoperation because of surgical bleeding. Disseminated intravascular coagulation developed in another patient. Sixty-eight patients (93%) needed red blood cell supplementation. Sixty-eight percent of patients between 1 month and 1 year old could be treated without any other postoperative transfusion except for red blood cell supplementation. In contrast, in the neonates, platelet concentrates or fresh frozen plasma, or both, were used in 61% of the patients. In addition to the known immaturity of the hemostatic system, the increased need for platelet concentrates in the neonates was attributed to longer cardiopulmonary bypass time, deeper hypothermia in association with circulatory arrest, larger dosages of heparin, and more extensive plasma dilution during cardiopulmonary bypass. In conclusion, a low rate of bleeding complications and acceptably low general blood loss can be achieved postoperatively with blood component therapy.

Infant vitamin B-6 status changes with age and with formula feeding

To study the effect of type of feeding on infant vitamin B-6 status, we determined erythrocyte pyridoxal 5'-phosphate concentration (EPLP) and erythrocyte aspartate aminotransferase basal activity (EASTo) and its activation coefficient (alpha EAST) in 109 infants at 2, 4, 6, 9, and 12 mo of age. Thirty-six infants were exclusively breast-fed for 9 mo. Forty-six infants were exclusively breast-fed for 6 mo, and then given solid foods in addition. Twenty-seven infants were weaned by 2-3 mo to an adapted cow milk-based formula (15 g protein/L and 0.6 mg pyridoxine/L) and given solid foods from 3 to 4 mo. Infant vitamin B-6 status was age-dependent; it was highest at 4 mo and thereafter gradually approached adult values. The larger the intake of formula, the higher the vitamin B-6 status. In formula-fed infants at ages 2-6 mo, 71-96% of the EPLP values and 57-70% of the EASTo values were above the 95th percentile, and 35-53% of the alpha EAST values were below the 5th percentile for these values in breast-fed infants. These findings raise the question of whether the vitamin B-6 content of formulas, especially in relation to protein content, should be reduced.

Insulin-like growth factor I and insulin-like growth factor binding protein 3 as determinants of blood hemoglobin concentration in healthy subjects

We studied the serum concentrations of IGF-I, IGF-binding protein 3 (IGFBP-3), and testosterone in relation to blood Hb in 60 healthy prepubertal or early pubertal boys twice, with a 9-mo interval. Serum IGF-I and testosterone levels were measured by RIA, and serum IGFBP-3 was measured by monoclonal immunofluorometric assay. Positive correlations were observed between the concentrations of blood Hb and serum IGF-I at the first examination (r = 0.36, p = 0.008) and Hb and IGFBP-3 at both examinations (r = 0.53, p < 0.001, and r = 0.39, p = 0.003). No association between Hb and testosterone concentrations was found. Our results show that blood Hb is positively correlated to serum IGF-I and IGFBP-3 levels, indicating indirectly the involvement of growth hormone in the regulation of physiologic Hb concentration. Because no association was found between Hb and testosterone concentrations, this may indicate that the role of androgens in erythropoiesis may be different at different stages of puberty. It is concluded that the IGF system may be involved in the rise of Hb level during early puberty.

Serum transferrin receptor and erythropoiesis in children with newly diagnosed acute lymphoblastic leukemia

Thirty-five children with acute lymphoblastic leukemia were monitored weekly during the first 12 weeks of chemotherapy. The transferrin receptor (TfR) concentration was 2.8 +/- 0.2 mg/l (mean +/- S.E.M.) at diagnosis, decreased up to 3 weeks, and then increased reaching a maximal level at 8 weeks. The mean values for reticulocyte counts followed a similar pattern. In contrast, serum erythropoietin and ferritin levels were generally high. Those patients whose erythropoiesis was more accelerated had higher serum TfR concentrations. We conclude that among these patients the TfR level reflected the rate of erythropoiesis and was independent of the level of erythropoietin.

Increases in hemoglobin concentration and iron needs in response to growth hormone treatment

We studied 36 children with short stature during the initial 6 months of recombinant human growth hormone treatment and found an elevation in the mean concentration of hemoglobin (p < 0.001). The elevation was highest in the eight patients with bone dysplasia (p < 0.001). The mean concentration of serum ferritin decreased (p < 0.01) and that of serum transferrin increased (p < 0.001). The prevalence of iron deficiency increased from 6 patients (17%) with initial deficiency to 20 (56%) patients after therapy, indicating that iron supplementation should be considered in children treated with recombinant human growth hormone.

Is serum transferrin receptor useful for detecting iron-deficiency in anaemic patients with chronic inflammatory diseases?

We investigated whether determination of serum transferrin receptor (TfR) is useful for detecting iron-deficiency in patients with chronic inflammatory diseases and for differentiating between iron-deficiency anaemia and anaemia of inflammation. Using an immunofluorometric assay, serum TfR was measured in 34 anaemic patients. Of these patients, 23 had a chronic rheumatic disease, 13 with both inflammation and iron-deficiency and 10 with anaemia of inflammation only; the other 11 patients had iron-deficiency anaemia and no evidence of inflammation. Serum TfR concentrations were lower in patients with anaemia of inflammation (2.6 +/- 0.2 mg/l, mean +/- S.E.M.) than in patients with iron-deficiency anaemia (6.7 +/- 1.1 mg/l, P < 0.01) or those with both inflammation and iron deficiency (5.8 +/- 1.0 mg/l, P < 0.01). Among patients with inflammatory disease, correlations between TfR and ferritin concentrations (r = -0.62, P < 0.05) and TfR and erythropoietin concentrations (r = 0.69, P < 0.001) were observed in iron-deficient subjects only. TfR, though not superior to serum ferritin, can help to distinguish between anaemia of inflammation and iron-deficiency anaemia and to identify iron-deficiency in subjects with chronic inflammation.

Early rise in serum concentration of transferrin receptor induced by recombinant human erythropoietin in very-low-birth-weight infants

The serum transferrin receptor (TfR) level reflects iron status and the rate of erythropoiesis. This study was undertaken to assess the role of serum TfR in the iron status and erythropoiesis in very-low-birth-weight infants under conditions in which erythropoiesis is stimulated by large doses of recombinant human erythropoietin (rHuEPO) and oral iron. The first 34 infants were followed from the 3rd to 11th wk of life or until discharged. They received iron at a rate of 3 mg/kg/d. The subsequent 21 infants were given rHuEPO (300 U/kg three times a week s.c.) and iron at a rate of 6 mg/kg/d from the 3rd or 4th wk of life for a mean of 3.4 wk. With this treatment, the need for transfusion was reduced from 1.4 +/- 0.4 to 0.1 +/- 0.1 transfusions per infant (p = 0.02). The serum TfR concentrations in the rHuEPO-treated infants increased gradually to values several-fold higher than those in the untreated infants. This increase was not related to intrauterine or postnatal growth, protein intake, or serum albumin concentration. Neither was an association observed between Hb and TfR concentration. In the treated infants, the serum ferritin concentration was lower at the 4th, 5th, and 7th wk of life than in the untreated infants. The very-low-birth-weight infants who were given large doses of rHuEPO and iron had a marked rise in serum TfR concentration and a small decline in serum ferritin concentration. These events have been related to iron deficiency.

Reference ranges for erythrocyte pyridoxal 5'-phosphate concentration and the erythrocyte aspartate transaminase stimulation test in lactating mothers and their infants

We determined reference ranges for erythrocyte pyridoxal 5'-phosphate concentrations (EPLP) and erythrocyte aspartate transaminase basal activities (EASTo) and activation coefficients (alpha EAST) in lactating mothers and infants from data of mothers receiving a vitamin B-6 supplement and infants breast-fed by mothers with adequate vitamin B6 status. The mothers' vitamin B6 status was assessed on the third day postpartum (pp) (n = 91) and at 2 mo (n = 114), 4 mo (n = 117), 6 mo (n = 110), and 9 mo (n = 40) pp and that of the exclusively breast-fed infants at 2 mo (n = 90), 4 mo (n = 106), and 6 mo (n = 99). We also examined 9-mo-old infants (n = 39) who, besides breast milk, had received solids after 6 mo, and 12-mo-old infants (n = 100) who had received solids beginning at 4-6 mo and dairy products at 9 mo. Values indicating deficiency for at least two of the three indexes distinguished the 5-10% of mothers and infants with the lowest vitamin B6 status. The reference ranges for EPLP, EASTo, and alpha EAST for infants and for mothers during the first months of lactation differ from those reported earlier for adults.

Zinc supplementation of infant formula

The effect of zinc supplementation of infant formula on zinc nutrition and growth of healthy infants was studied longitudinally from birth to age 12 mo. The zinc-supplemented group (n = 16) received the same formula as the unsupplemented group (n = 16) except for the addition of 61 mumol (4 mg) Zn/L as sulfate. After age 2 mo in the breast-fed and unsupplemented groups the mean serum zinc concentration remained stable at approximately 9.9 mumol/L. The zinc supplement increased the mean serum zinc concentration to 13.0 mumol/L by age 6 mo. With increasing intake of solid foods, the concentration fell by age 9 mo to the same concentration as in the other groups. The supplement did not increase the velocity of weight or length growth. In their growth the unsupplemented infants were not inferior to the breast-fed or zinc-supplemented infants.