Zinc protoporphyrin/heme ratio as parameter of iron status in moderately preterm infants: natural course and associations in the first 4 months.

OBJECTIVE: To determine the natural course of zinc protoporphyrin/heme ratio (ZnPP/H) and its role in the detection of iron deficiency (ID) and iron-deficiency anemia (IDA) in the first 4 months of life in moderately preterm infants. STUDY DESIGN: ZnPP/H was measured at 1 week, 6 weeks and 4 months postnatal age in a prospective cohort of 161 Dutch infants born at a gestational age of 32+0 to 36+6 weeks who did not receive an erythrocyte transfusion or iron supplementation. RESULTS: ZnPP/H levels decreased in the first 6 weeks and increased thereafter. At 4 months postnatal age, ZnPP/H was higher in the 11 (8.5%) infants with IDA (mean (s.d.): 260.8 (16.1)) but not in the 27 (21.3%) infants with ID (mean (s.d.): 177.0 (15.1)) compared with normal infants (mean (s.d.): 157.3 (12.5)). CONCLUSION: In moderately preterm infants, ZnPP/H can be of additional value to detect infants at risk for IDA due to iron-deficient erythropoiesis at 4 months of age.

Predictive factors of iron depletion in late preterm infants at the postnatal age of 6 weeks.

BACKGROUND/OBJECTIVES: Late preterm infants (born ⩾32 weeks of gestation) are at risk for developing iron deficiency and iron deficiency anaemia, and this may lead to impaired neurodevelopment. In the Netherlands, there is no guideline for standardised iron supplementation in these infants. Individualised iron supplementation has been suggested (that is, treating those infants with the highest risk), but risk factors for deprived iron stores in this specific group of infants are not well documented. SUBJECTS/METHODS: In this prospective multi-centre study, we analysed the iron status at the postnatal age of 6 weeks of 68 infants born between 32 and 35 weeks of gestation in the Netherlands. Serum ferritin (SF) <70 µg/l in the absence of infection (C-reactive protein <5 mg/l) was defined as iron depletion and whenever in combination with a haemoglobin level <110 mg/dl as iron-depleted anaemia. Medical charts were reviewed to identify risk factors. RESULTS: Iron depletion and iron-depleted anaemia were present in 38.2% and 30.9% of the infants, respectively. Infants with a birth weight <1830 g and a SF <155 µg/l in the first week of life had a 26.4 times higher risk to develop iron depletion (95% confidence interval 3.1-227.0, P=0.003). Multivariate regression analyses also showed that iron depletion was associated with a higher number of blood draws. CONCLUSIONS: Iron depletion is common in late preterm infants at the age of 6 weeks in a setting without standardised iron supplementation. One should consider early individualised iron supplementation for late preterm infants with a low birth weight (<1830 g), and a low SF in the first week of life (<155 µg/l), as they have a high risk to develop iron depletion.

Iron deficiency in the first 6 months of age in infants born between 32 and 37 weeks of gestational age.

BACKGROUND/OBJECTIVES: Preterm infants are at risk of iron deficiency (ID). In the Netherlands, preterm infants born after 32 weeks of gestational age (GA) do not receive iron supplementation on a routine basis. We hypothesized that dietary iron intake in these infants might not be sufficient to meet the high iron requirements during the first 6 months of life. SUBJECTS/METHODS: In a prospective cohort study, we analyzed the prevalence and risk factors of ID in 143 infants born between 32+0 and 36+6 weeks GA who did not receive iron supplementation. RESULTS: ID at the age of 4 and 6 months was present in 27 (18.9%) and 7 (4.9%) infants. Results of a multivariable logistic regression analysis showed that ID was associated with lower birth weight, a shorter duration of formula feeding, more weight gain in the first 6 months of life and lower ferritin concentrations at the age of 1 week. CONCLUSIONS: Preterm infants born after 32 weeks GA have an increased risk of ID compared with those born at term, supporting the need of iron supplementation. Our results suggests that measurement of ferritin at the age of 1 week might be useful to identify those infants at particular risk and could be used in populations without general supplementation programs. However, the efficacy and safety of individualized iron supplementation, based on ferritin concentrations at the age of 1 week, together with other predictors of ID, needs to be further investigated, preferably in a randomized controlled trial.

PIV quantification of the flow induced by an ultrasonic horn and numerical modeling of the flow and related processing times.

The flow in a confined container induced by an ultrasonic horn is measured by Particle Image Velocimetry (PIV). This flow is caused by acoustic streaming and highly influenced by the presence of cavitation. The jet-like experimentally observed flow is compared with the available theoretical solution for a turbulent free round jet. The similarity between both flows enables a simplified numerical model to be made, whilst the phenomenon is very difficult to simulate otherwise. The numerical model requires only two parameters, i.e. the flow momentum and turbulent kinetic energy at the position of the horn tip. The simulated flow is used as a basis for the calculation of the time required for the entire liquid volume to pass through the active cavitation region.

Pseudothrombocytopenia in a neonate due to mother?

UNLABELLED: Ethylenediaminetetraacetic acid (EDTA)-dependent pseudothrombocytopenia (PTCP) is the phenomenon of a false low platelet count reported by an automated haematology analyzer due to in vitro aggregation of platelets. This aggregation is due to the interaction between antibodies and EDTA-dependent crypt antigens on platelets. We observed a new born child whose mother was diagnosed with transient PTCP due to transplacental transmission of maternal immunoglobulin G antibodies during pregnancy. CONCLUSION: Although maternal-neonatal PTCP is rare, it is important to consider this phenomenon as a cause of trombocytopenia, as it can result in unnecessary diagnostic workup and treatment.

[Tick-borne disease or not? Do not let yourself be fooled]. / Tekenbeetziekte ofniet? Laat u niet beetnemen.

Confusion among physicians and patients is increasing regarding the diagnosis and treatment ofLyme borreliosis due to the enormous amount ofambiguous information available and media attention. Some of the dilemmas that physicians encounter are illustrated by 3 patients with a range of symptoms, one of whom was convinced she had Lyme borreliosis. However none of these patients had significant evidence that suggested Lyme borreliosis. Physicians should follow the guidelines developed by the Dutch Institute for Health Care Improvement (CBO) or the Infectious Diseases Society of America rather than 'alternative' guidelines, which are not evidence-based.

The development of truncated inviscid turbulence and the Fermi-Pasta-Ulam problem.

A study was made of the possible similarity between the development of truncated, inviscid turbulence and the Fermi-Pasta-Ulam (FPU) problem. For the case of a constant time scale, which resembles the FPU problem, a significant increase in the time to achieve equipartition was found when the initial energy was decreased. At first a few modes were generated and only rather late in the spectral development other modes appear and equipartition was established.

[Diagnostic image (268). A man with 'pyodermia' in the beard area]. / Diagnose in beeld (268). Een man met 'pyodermie' in de baardstreek.

A 61-year-old man developed tinea barbae (kerion barbae) caused by Trichophyton mentagrophytes varietas interdigitale following prolonged intensive care treatment for septic shock and meningitis. Whenever a suppurative folliculitis develops, fungal infection is a possible cause.

[Two children seriously weakened by myasthenia]. / Twee ernstig verzwakte kinderen door myasthenie.

Two boys, aged 2 and 11 years, presented with fever and muscle weakness that resulted in respiratory insufficiency. A physical examination and additional tests confirmed the diagnosis 'myasthenia'. Acetyl cholinesterase-inhibitor therapy had a favourable effect. Myasthenia is a diagnosis that should be considered for every child presenting with muscle weakness of unknown origin.

Catch-up growth and endocrine changes in childhood celiac disease. Endocrine changes during catch-up growth.

Childhood celiac disease may lead to a failure of statural growth. After institution of a gluten-free diet most patients exhibit catch-up growth. Catch-up growth is a remarkable phenomenon characterized by a supranormal height velocity. One of the hypothetical mechanisms of catch-up growth is that an increased activity of the somatotrophic axis is involved. In order to provide further insight in the physiology of catch-up growth, auxological and endocrine changes were prospectively studied in 28 children with newly diagnosed celiac disease. The results demonstrate a malnutrition-like state of the somatotrophic axis at the time of diagnosis and a rapid recovery of this axis towards normal functioning after institution of the gluten-free diet. Although several correlations between these endocrine alterations and auxological parameters were detected, it is questionable whether the endocrine changes are the driving force behind catch-up growth.