Decreased ferritin levels, despite iron supplementation, during erythropoietin therapy in anaemia of prematurity

Erythropoietin (rHuEPO) therapy has been shown to be beneficial in preventing and treating anaemia of prematurity and to decrease the need for blood transfusions. There is, however, only scanty data on the effect of rHuEPO therapy on iron metabolism. We studied 29 preterm infants (age 34 ± 14 days) who were randomly assigned to receive either rHuEPO 900 U kg^-1 week^-1 with 6 mg kg^-1 day^-1 of iron for 4 weeks ( n= 15) or no therapy. The following parameters were evaluated and compared between and within groups at the beginning, during and at the end of the study: Haematocrit (SI), reticulocytes (10⁹μgl^-1), serum ferritin (μg1^-1) and iron (μmol 1^-1). The results were as follows. At the baseline, erythropoietin levels were similar in both groups: 7.2 ± 5.6 versus 6.2 ± 3.2 mU ml^-1 (NS). In the treated infants the haematocrit remained stable during the study and was significantly higher than in the control group by the end of the study: 0.34 ± 0.03 versus 0.28 ± 0.05 ( p = O.001). rHuEPO therapy increased the reticulocyte count from 130 ± 70 to 430 ± 200 ( p = 0.0002). However, rHuEPO therapy depleted both serum ferritin and it-on levels from 321 ± 191 to 76 ± 58 $uMgl^-1 ( p = 0.04) and from 18 ± 5 to 13 ± 4 μmoll^-1 ( p = 0.03), respectively. We conclude that rHuEPO therapy prevented anaemia and its sequelae; however, serum ferritin and iron levels were depleted. We suggest that the effect of rHuEPO may be further increased by higher iron supplementation.     

Vitamin K in preterm breastmilk with maternal supplementation

Six healthy lactating mothers who gave birth to preterm infants at a median post conceptional age of 29.5 (range 26-30) weeks were given 2.5 mg phylloquinone (vitamin K1) orally daily for 2 weeks beginning at a median postconceptional age of 31.5 (range 28–32) weeks. Phylloquinone was measured in the breastmilk daily for 14 d. Trough plasma phylloquinone concentrations were also determined on four occasions. Phylloquinone levels in the breastmilk increased from a baseline of 3 ± 2.3ngml^-1 to 22.6 ± 16.3 ng ml^-1 (mean ± SD) after the first dose ( p < 0:05); a gradual increase was noted until phylloquinone levels reached a plateau of 64.2 ± 31.4ng ml^-1 after the sixth daily dose.     

Birth stress increases adrenomedullin in the newborn

Adrenomedullin is a peptide that induces pulmonary vasodilation in experimental animals. Adrenomedullin was measured in blood samples from cord artery and vein from 41 term newborns. In 23 of the newborns delivered vaginally, levels of adrenomedullin in the cord artery, 71.8 ± 45.8 pg ml^-1 (mean ± SD), and vein, 75.6 ± 45.2 pg ml^-1, were significantly higher than in 18 newborns delivered by elective Caesarean section (40.7 ± 14.6pgml^-1 and 32.4 ±10.3 pgml^-1, respectively; both p < 0:01). A significant correlation existed between the concentration of adrenomedullin and pH in the cord artery ( r = - 0:545, p = 0:002). The fetus responds to birth stress by secreting high concentrations of adrenomedullin. As a potent vasodilator, the peptide may play a role in postnatal cardiovascular adaptation.     

Diagnostic value of plasma levels of tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) in newborns with sepsis

The aim of this study was to examine if TNFα and IL-6 plasma levels could be of value in diagnosing neonatal sepsis. Tumor necrosis factor α (TNFα) and interleukin-6 (IL-6) plasma levels were determined in 15 newborn infants with confirmed sepsis (group I), 18 with suspected sepsis (group II) and 22 control infants (group III). In 33 newborns, initially suspected of having sepsis (groups I and 11), a positive test result for plasma concentration of TNFα (> 70 pg/ml) had a sensitivity of 73 % and a specificity of 94%. A positive test result for IL-6 (>500 pg/ml) had a sensitivity of 80% and a specificity of 78%. When plasma levels of TNFα and IL-6 were combined for the diagnosis of neonatal sepsis, a positive test result for both tests had a sensitivity of 60% and a specificity of 100%. When both tests are positive the diagnosis of neonatal sepsis is almost certain (likelihood ratio =α. The combination of TNFα and IL-6 determinations appears to be a good predictor of neonatal sepsis.     

Insulin secretion and hepatic insulin clearance as determinants of hyperinsulinaemia in normotolerant grossly obese adolescents

Obesity is characterized by variable degrees of hyperinsulinaemia, which has been attributed to either β-cell hypersecretion or reduced hepatic insulin extraction, or both. To investigate this controversial issue, a 4-h frequently sampled i.v. glucose tolerance test (glucose dose 12.8 g m^-2) was performed in 13 normotolerant, grossly obese adolescents (10 F/3 M; 13 ± 1 y; body mass index 32 ± 0.9; pubertal stage 4–5; obesity duration 7.8 ± 3 y) and in a comparable group of 8 healthy, normal-weight subjects. Glucose, insulin and C-peptide time-course were analysed by the minimal model technique, which estimates β-cell secretion, insulin sensitivity ( S _i), glucose effectiveness ( S _G) and hepatic insulin extraction (HE). Despite similar fasting and after load glucose patterns ( S _G similar in the two groups), obese adolescents showed sustained peripheral hyperinsulinaemia (total insulin area under the concentration curve 67.2 ± 10.8 vs 19.1 ± 1.2 pmol l^-1 in 240 min; p < 0:002) and a 71% reduction in S _i (2.02 ± 0.33 vs 6.95 ± 1.03±10⁴ min^-1 (μU ml^-1); p < 0:001). Compared with control subjects, the total amounts of prehepatic insulin secretion and posthepatic insulin delivery were also increased significantly in obese adolescents by 30% and 46%, respectively; HE was reduced by 15% during the first 30 min of the test, but recovered within the normal range during the rest of the test. In conclusion, severely obese adolescents are insulin resistant and their hyperinsulinaemia is primarily caused by β-cell hypersecretion, whereas the reduction in insulin hepatic extraction is a transient metabolic phenomenon.     

Glycerol carbon contributes to hepatic glucose production during the first eight hours in healthy term infants

The newborn infant must mobilize endogenous substrate stores to meet the requirements of glucose-dependent organs. High concentrations of free fatty acids and glycerol, and a rapid decrease in the respiratory quotient, indicate that lipids are an important fuel soon after birth. The purpose of the present study was to determine the onset of lipolysis and gluconeogenesis from glycerol in healthy, term, unfed infants. Eight infants were studied from a postnatal age of 3.5 ± 0.5 h to 7.4±0.2h using [6,6-²H₂]glucose and [2-¹³C]glycerol analysed by gas chromatography/mass spectrometry. Plasma concentrations of glucose, glycerol and insulin averaged 2.9±0.4mM, 369±89μM and 9.4 ±3.7 μU·ml^-1, respectively. The hepatic glucose production rate averaged 25.0±3.5 μmol·kg^-1 min^-1 (4.5 ±0.6mgkg^-1·min^-1) and the endogenous plasma appearance rate of glycerol 8.7±1.2/μmol·kg^-1min^-1. On average, 57.9±8.4% of the glycerol was converted to glucose, representing 11.1 ± 2.3% of hepatic glucose output. Thus, lipolysis and gluconeogenesis from glycerol are established within the first 8 h of life in term infants.     

Fibronectin in Meningococcal Sepsis

ABSTRACT. Plasma fibronectin was measured with Laurell's immunoelectroassay in 44 patients with meningococcal sepsis. The average value (15.0±7.9 mg/dl) was lower than that in normal children (27.4±8.7 mg/dl) (p<0.001). Fibronectin in patients correlated positively with antithrombin III (AT-III) values (p<0.02), but not with protein C (0.05+), than in those without DIC (DIC⁻) (p<0.02), but were lower in both groups than in a normal control group. A negative correlation between fibronectin and protein C was only present in DIC⁻ patients (r:-0.773=p<0.01). Fibronectin varied independent of AT-III and protein C in DIC⁺ patients. The study was repeated in 11 patients 24 hours after admission when fibronectin had decreased in 7/11 cases (mean decrease: -2.7±8.7 mg/dl). This variation correlated in a negative way with AT-III (r:-0.659=p<0.05). In meningococcal sepsis fibronectin decreases very early, even in DIC⁻ patients and its relationship to AT-III and protein C is different, depending on the presence of DIC and on the stage of evolution of the disease.     

Low sodium levels in serum are associated with subsequent febrile seizures

Fever plays an important role in causing disturbances in fluid and electrolyte balance. Hyponatraemia has been thought to enhance the susceptibility to seizures associated with febrile illnesses in childhood. We have studied serum electrolyte levels in children with simple and complicated febrile convulsions. Sodium levels were lower in those children with complicated convulsions in comparison with those having simple convulsions (136.07 ± 3.06 mmoll⁻¹, mean ± SD, n = 42, and 137.62 ±2.63mmoir¹, n = 71, respectively; p < 0.01, Student's Mest). The sodium concentrations were lowest in children with repeated seizures (134.20 ± 2.30 mmoll⁻¹, n= 15) compared with children having simple ( p < 0.01, ANOVA, Duncan's test) or other complicated types of febrile convulsions: focal seizures (137.08 ± 3.82 mmoir¹, n = 12, p < 0.01), seizures lasting longer than 15 minutes (138.00 ± 2.45 mmoll⁻¹, n = 5, p < 0.05) and children over 5 years (136.70 ±2.06 mmoll⁻¹, n = 10, p < 0.05). Serum potassium levels showed no statistically significant differences between the patient groups. Our results show that hyponatraemia may increase the risk for multiple convulsions during the same febrile illness.     

Is thrombocytopenia suggestive of organism‐specific response in neonatal sepsis?

Background:  It is controversial whether thrombocytopenia is suggestive of one (or more) causative agents of neonatal sepsis: a low platelet count has been related in turn to Gram-positive, Gram-negative or fungal sepsis.
Methods:  A retrospective, cohort study on 514 very low-birthweight (VLBW) neonates admitted over a 9 year period to a large tertiary neonatal intensive care unit (NICU) in Italy was carried out. Through database search, data on platelet counts, sepsis, clinical course, and microbiological culture were collected and analyzed. Statistical analysis was performed to look for significant association between thrombocytopenia and sepsis caused by different (Gram-positive, Gram-negative or fungal) organisms.
Results:  Sepsis diagnosed on microbiological criteria occurred in 197 of 514 VLBW neonates (38.3%), and thrombocytopenia (at least one finding of platelet count <80 000/mm³) was detected in 34 (17.2%) of the 197 septic infants. Thrombocytopenia occurred in 10 of 51 neonates with fungal sepsis (19.6%), and in 24 of 146 with bacterial sepsis (16.4%; P  = 0.37). The difference was not significant when clustering for sepsis caused by Gram-positive (nine thrombocytopenic of 51 with Gram-positive sepsis, 17.6%; P  = 0.40) and Gram-negative organisms (15/95, 15.7%; P  = 0.22), or when considering only coagulase-negative Staphylococcus sepsis (6/37, 16.2%; P  = 0.25).
Conclusions:  In contrast with previous reports, thrombocytopenia might not be an organism-specific marker of sepsis. Caution should be maintained in relating a low platelet count to any infectious agent (or group of agents) in preterm VLBW neonates.     

Mean Cellular Volume of Urinanry Red Blood Cells in Investigation of Hematuria

The mean cellular volume (MCV) of urinary red blood cells (RBCs) of pediatric patients with glomerular (group I; n = 52) and nonglomerular (group II; n = 21) hematuria was determined using an automated bloodell analyzer. Group I patients had a significantly lower MCV than group II (61 ± 8 w. 88 ± 15 μm³, mean ± SD; p<0.001). With a MCV of 75 μm³ taken as the dividmg line between glomerular and nonglomerular hematuria, correct assessment of the site of bleeding was made in 67 of the 73 (92%) patients studied. Determination of the MCV of urinary RBCs is a simple noninvasive test for localizing the site of hemaw in pediatric patients.     

Endothelium-derived relaxing and contracting factors during the early neonatal period

Abstract The interaction and relative potency of nitric oxide, an endothelium-derived relaxing factor, and endothelin-1, an endothelium-derived contracting factor, may be important in the transition from fetal to extrauterine life. The change in level of nitric oxide during the early neonatal period has not been measured. Accordingly, the serum levels of nitric oxide metabolites (the sum of nitrite and nitrate) and plasma endothelin-1 were determined in 20 healthy neonates at birth, at 12 and 24 h postnatally, and at the age of 5 d. The lowest serum concentration of nitric oxide metabolites was observed at birth (26.2 ± 9.1 µmol 1^-1, mean ± SD) and increased with age, whereas the highest plasma concentration of endothelin-1 was observed at birth (14.0 ± 6.7 pg ml^-1) and decreased with age. These changes suggest that nitric oxide and endothelin-1 play roles in the circulatory adaptation of the neonate to extrauterine life.     

Immunoregulation with Levamisole in Children with Frequently Relapsing Steroid Responsive Nephrotic Syndrome

ABSTRACT. The immunological and clinical effects of levamisole were studied in 10 children with frequently relapsing steroid responsive nephrotic syndrome (SRNS). The efficacy of the drug was tested during remission of the disease with all patients on alternate day steroid therapy. The lymphocyte proliferative response to phytohemagglutinin (PHA), concanavalin-A (Con-A) and pokeweed mitogen (PWM) were normal. The Con-A induced suppressor T-lymphocyte activity of 7 patients was low before treatment with levamisole 8±3.7% and increased to normal values during therapy 34±6%; p <0.001 (control 32±5%). In these 7 children prednisolone dosage could be decreased significantly or discontinued altogether (44.1±5.3%). Patients without immunoregulatory abnormalities did not respond to levamisole. In 3 out of 4 children tested the percentage of OKT8⁺ cells rose during levamisole therapy from 19.7±2.1 to 37±2.3 ( p <0.001), thus correcting the elevated pre-treatment OKT4⁺/OKT8⁺ ratio from 3.1±0.2 to 1.5±0.2; p <0.001 (control 1.47±0.2). These data support the hypothesis that abnormal immunoregulation may play a role in the pathogenesis of SRNS. Treatment with levamisole can be useful in some patients with the frequently relapsing form of the disease.     

儿童急性淋巴细胞白血病中性粒细胞缺乏伴发热单中心血流感染病原菌分析

目的 分析儿童急性淋巴细胞白血病(ALL)化疗后中性粒细胞缺乏伴发热(FN)血流感染的临床特点、危险因素和病原菌分布。方法 回顾性分析2007年1月1日至2016年12月31日上海交通大学附属儿童医院血液肿瘤科收治的ALL化疗后发生FN住院患儿的临床资料和血培养结果,分析菌株的分布及药敏特点。结果 纳入ALL患儿312例,FN1 548例次,共送检1 700例次血培养,血培养阳性率7.5%(127/1 700),血流感染发生率8.2%(127/1 548),病死率9.4%(12/127)。血流感染革兰阳性菌51.1%(65/127),革兰阴性菌47.2%(60/127),真菌1.5%(2/127)。革兰阴性菌血流感染与革兰阳性菌血流感染比较,ANC<0.1×10⁹·L^-1的患儿占比(P=0.041)和感染性休克发生率更高(P=0.002)。2012~2016年铜绿假单胞菌构成比较2007~2011年增加(χ²=4.712,P=0.030)。ALL的危险程度分层IR/HR(OR=2.560,P=0.045)和ANC<0.1×10⁹·L^-1(OR=0.754,P=0.025)是血流感染发生的独立危险因素。结论 ALL患儿发生FN时血流感染病原菌阳性率较高(8.2%),以革兰阳性菌感染为主。在严重粒细胞缺乏时以革兰阴性菌血流感染为主,铜绿假单胞菌感染有增加趋势,合并感染性休克是FN死亡的独立危险因素。     

儿童急性淋巴细胞白血病中性粒细胞缺乏伴发热单中心血流感染病原菌分析

目的 分析儿童急性淋巴细胞白血病(ALL)化疗后中性粒细胞缺乏伴发热(FN)血流感染的临床特点、危险因素和病原菌分布。方法 回顾性分析2007年1月1日至2016年12月31日上海交通大学附属儿童医院血液肿瘤科收治的ALL化疗后发生FN住院患儿的临床资料和血培养结果,分析菌株的分布及药敏特点。结果 纳入ALL患儿312例,FN1 548例次,共送检1 700例次血培养,血培养阳性率7.5%(127/1 700),血流感染发生率8.2%(127/1 548),病死率9.4%(12/127)。血流感染革兰阳性菌51.1%(65/127),革兰阴性菌47.2%(60/127),真菌1.5%(2/127)。革兰阴性菌血流感染与革兰阳性菌血流感染比较,ANC<0.1×10⁹·L^-1的患儿占比(P=0.041)和感染性休克发生率更高(P=0.002)。2012~2016年铜绿假单胞菌构成比较2007~2011年增加(χ²=4.712,P=0.030)。ALL的危险程度分层IR/HR(OR=2.560,P=0.045)和ANC<0.1×10⁹·L^-1(OR=0.754,P=0.025)是血流感染发生的独立危险因素。结论 ALL患儿发生FN时血流感染病原菌阳性率较高(8.2%),以革兰阳性菌感染为主。在严重粒细胞缺乏时以革兰阴性菌血流感染为主,铜绿假单胞菌感染有增加趋势,合并感染性休克是FN死亡的独立危险因素。     

Arachidonic acid metabolites in CSF in hypoxic-ischaemic encephalopathy of newborn infants

The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF _1-α, TXB₂, PGE₂ and PGF_2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB₂ (thromboxane A₂ metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF _1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB₂ was higher than the rise in 6-keto-PGF _1-α.     

Randomized trial comparing natural and synthetic surfactant: increased infection rate after natural surfactant?

The efficacy of a natural porcine surfactant and a synthetic surfactant were compared in a randomized trial. In three neonatal intensive care units, 228 neonates with respiratory distress and a ratio of arterial to alveolar partial pressure of oxygen <0.22 were randomly assigned to receive either Curosurf 100mgkg⁻¹ or Exosurf Neonatal 5 ml kg⁻¹. After Curosurf, the fraction of inspired oxygen was lower from 15min (0.45 ± 0.22 vs 0.70 ± 0.22, p = 0.0001) to 6 h (0.48 ± 0.26 vs 0.64 ± 0.23, p = 0.0001) and the mean airway pressure was lower at 1 h (8.3 3.2 mmH₂O vs 9.4 ± 3.1 mmH₂O β= 0.01). Thereafter the respiratory parameters were similar. The duration of mechanical ventilation (median 6 vs 5 d) and the duration of oxygen supplementation (median 5 vs 4 d) were similar for Curosurf and Exosurf After Curosurf, C-reactive protein value over 40 mg r¹ occurred in 45% (vs 12%; RR 3.62, 95%CI 2.12-6.17, p = 0.001), leukopenia in 52% (vs 28%; RR 1.85, 95%CI 1.31-2.61, β= 0.001) and bacteraemia in 11% (vs 4%; RR3.17, 95%CI 1.05-9.52, p < 0.05).
We conclude that when given as rescue therapy Curosurf had no advantage compared with Exosurf in addition to the more effective initial response. Curosurf may increase the risk of infection.     

Physical effects of growth hormone treatment in children with Prader-Willi syndrome

A randomized, controlled study of 54 children (age, 4-16 years) with Prader-Willi syndrome was conducted to assess the potential beneficial effects of growth hormone (GH) treatment. After observation for 6 months, the children were randomized to receive GH at a dose of 3 IU/m²/day (1 mg/m²/day) ( n = 35) or no intervention ( n = 19). The effects of GH treatment on linear growth, body composition, muscle strength, pulmonary function and resting energy expenditure were assessed. The levels of GH secreted in resonse to clonidine stimulation were universally low, and mean (± SD) insulin-like growth factor I SDS was -1.2 ± 0.8 pretreatment. In children treated for 1 year, mean height velocity SDS significantly increased from -1.0 ± 2.5 to 4.6 ± 2.9 ( p < 0.0001), mean percentage body fat decreased from 46.3 ± 8.4% to 38.4 ± 10.7% ( p < 0.001), mean lean body mass increased from 20.5 ± 6.3 kg to 25.6 ± 4.3 kg ( p <0.01) and respiratory muscle function and physical strength imporved. Mean respiratory quotients significantly decreased from 0.81 to 0.77 ( p < 0.001); however, resting energy expenditure did not change. Therefore, GH therapy appears to reduce some of the physical disabilities experienced by children with Prader-Willi syndrome.     

The captopril test in children with renovascular and renal hypertension

We used the captopril test (CT) in 32 children, 8 with renovascular hypertension (RVH), 17 with renal hypertension (RH) and 7 with normal blood pressure, in order to study the renin-angiotensin system activation (RASA). All children affected by RVH presented a positive CT: a post-captopril plasma renin activity (PRA) of 12 ng ml^-1 h ^-1 or more, an absolute PRA increase of 10 ng ml ^-1 h ^-1 or more and a 150% increase or more, or 400% or more if the baseline PRA was less than 3 ng ml^-1 h^-1. The CT may be useful for demonstrating the RASA in RVH.     

HYPOCALCEMIA IN INFANTS OF DIABETIC MOTHERS

ABSTRACT. Twenty-two infants of diabetic mothers (IDM) were studied and were divided into two groups: a first group of 14 IDM did not receive vitamin D3 and was studied at birth and at 2, 24, 48 and 120 hours; a second group was given daily dosage of 60 μg of vitamin D3 from 3 hours to 120 hours and was studied at 2 hours and 120 hours.
In the first group, serum calcium levels decreased markedly during the first 24 hours of life (mean ± SD: 1.77±0.3 mmol/1, p <0.01) and remained low at 5 days. Serum phosphorus levels remained normal but serum magnesium levels decreased significantly at 24 hours (mean ± SD: 0.64±0.108 mmol/1, p <0.01) and returned to normal at 5 days. Serum immunoreactive parathormone levels increased consistently to high levels at 24 hours and remained elevated at 120 hours ( p <0.001). Serum immunoreactive calcitonin levels increased at 24 hours ( p <0.001) and decreased at 120 hours to low or undetectable values in all infants.
In group II, serum 25O-HD levels and 1.25 OH₂ D levels increased significantly ( p <0.001) respectively to 27.2±2.7 ng/ml and 114±20 pg/ml at 5 days. The results of this study show hypocalcemia to be a common event in IDM during the first days of life and furthermore hypophosphatemia, hypoparathyroidism, hypomagnesemia or defect of vitamine D metabolism would not seem to be the main etiological factors.     

Dietary iron intake and iron status in adolescents

The aim of this study was to evaluate the dietary iron intake of 15-year-old adolescents from two different regions of Sweden, in relation to their iron status. The study comprised 185 boys and 209 girls, randomly selected from the official population register. The iron intake was calculated from a 7-day record, and varied between 7 and 35 and 6 and 27 mg per day for boys and girls, respectively. The daily median intakes in boys and girls were 18.7 and 14.2 mg, respectively. S-ferritin, s-iron, and s-transferrin saturation, measured in all the subjects, did not differ significantly between the two regions. However, the mean serum ferritin concentration was significantly higher in the boys (36.4μgl^-1) than in the girls (29.4μgl^-1)( p < 0.001). Low s-ferritin levels, defined as s-ferritin < 12 μgl^-1 were found in seven boys (3.7%) and in 29 girls (13.9%). None of the adolescents had iron deficiency anaemia, defined as Hb< 110gl^-1 in combination with s-ferritin < 12μgl^-1. Regression and correlation analyses did not show any significant correlation between dietary iron intake and s-ferritin, or between s-ferritin and haemoglobin (Hb), MCH and MCHC. A significant correlation was found, however, between s-ferritin and transferrin saturation ( p < 0.005) in both sexes. When the adolescents who still had s-ferritin < 12μgl^-1 at a second blood examination were given a 6 weeks trial with oral iron therapy, all of them showed an increase both in s-ferritin and in blood Hb. The 95% confidence intervals of s-ferritin for 15-year-old Swedish boys and girls were defined as 11-90 and 7 85 μ.gl^-1, respectively.