Open Access

Objective Congenital hyperinsulinism (CHI) is a rare disease characterized by persistent hypoglycemia as a result of inappropriate insulin secretion, which can lead to irreversible neurological defects in infants. Poor efficacy and strong adverse effects of the current medications impede successful treatment. The aim of the study was to investigate new approaches to silence β-cells and thus attenuate insulin secretion. Research Design and Methods In the scope of our research, we tested substances more selective and more potent than the gold standard diazoxide that also interact with neuroendocrine ATP-sensitive K+ (KATP) channels. Additionally, KATP channel-independent targets as Ca2+-activated K+ channels of intermediate conductance (KCa3.1) and L-type Ca2+ channels were investigated. Experiments were performed using human islet cell clusters isolated from tissue of CHI patients (histologically classified as pathological) and islet cell clusters obtained from C57BL/6N (WT) or SUR1 knockout (SUR1-/-) mice. The cytosolic Ca2+ concentration ([Ca2+]c) was used as a parameter for the pathway regulated by electrical activity and was determined by fura-2 fluorescence. The mitochondrial membrane potential (ΔΨ) was determined by rhodamine 123 fluorescence and single channel currents were measured by the patch-clamp technique. Results The selective KATP channel opener NN414 (5 µM) diminished [Ca2+]c in isolated human CHI islet cell clusters and WT mouse islet cell clusters stimulated with 10 mM glucose. In islet cell clusters lacking functional KATP channels (SUR1-/-) the drug was without effect. VU0071063 (30 µM), another KATP channel opener considered to be selective, lowered [Ca2+]c in human CHI islet cell clusters. The compound was also effective in islet cell clusters from SUR1-/- mice, showing that [Ca2+]c is influenced by additional effects besides KATP channels. Contrasting to NN414, the drug depolarized ΔΨ in murine islet cell clusters pointing to severe interference with mitochondrial metabolism. An opener of KCa3.1 channels, DCEBIO (100 µM), significantly decreased [Ca2+]c in SUR1-/- and human CHI islet cell clusters. To target L-type Ca2+ channels we tested two already approved drugs, dextromethorphan (DXM) and simvastatin. DXM (100 µM) efficiently diminished [Ca2+]c in stimulated human CHI islet cell clusters as well as in stimulated SUR1-/- islet cell clusters. Similar effects on [Ca2+]c were observed in experiments with simvastatin (7.2 µM). Conclusions NN414 seems to provide a good alternative to the currently used KATP channel opener diazoxide. Targeting KCa3.1 channels by channel openers or L-type Ca2+ channels by DXM or simvastatin might be valuable approaches for treatment of CHI caused by mutations of KATP channels not sensitive to KATP channel openers.

For surgery in congenital hyperinsulinism (CHI), a distinct surgical strategy and technique is required for focal, diffuse and atypical CHI. In focal CHI, a confined, localized and parenchyma-sparing resection which is guided by the PET-CT is always indicated in order to cure the patient. In diffuse CHI, however, the results of surgical therapy are unpredictable and cure is an exception. Therefore, a strong tendency exists nowadays that medical therapy should be preferred in diffuse CHI. In atypical CHI the situation is more complex: if the focal lesion or the segmental mosaic are not too extensive, cure by resection should be possible. But care must be taken in atypical cases not to resect too much of the gland in order not to induce diabetes.

Background: Levels or fluctuations in the partial pressure of CO₂ (PCO₂) may affect outcomes for extremely low birth weight infants. Objectives: In an exploratory analysis of a randomized trial, we hypothesized that the PCO₂ values achieved could be related to significant outcomes. Methods: On each treatment day, infants were divided into 4 groups: relative hypocapnia, normocapnia, hypercapnia, or fluctuating PCO₂. Ultimate assignment to a group for the purpose of this analysis was made according to the group in which an infant spent the most days. Statistical analyses were performed with analysis of variance (ANOVA), the Kruskal-Wallis test, the χ² test, and the Fisher exact test as well as by multiple logistic regression. Results: Of the 359 infants, 57 were classified as hypocapnic, 230 as normocapnic, 70 as hypercapnic, and 2 as fluctuating PCO₂. Hypercapnic infants had a higher average product of mean airway pressure and fraction of inspired oxygen (MAP × FiO₂). For this group, mortality was higher, as was the likelihood of having moderate/severe bronchopulmonary dysplasia (BPD), necrotizing enterocolitis (NEC), and poorer neurodevelopment. Multiple logistic regression analyses showed an increased risk for BPD or death associated with birth weight (p < 0.001) and MAP × FiO₂ (p < 0.01). The incidence of adverse neurodevelopment was associated with birth weight (p < 0.001) and intraventricular hemorrhage (IVH; p < 0.01). Conclusions: Birth weight and respiratory morbidity, as measured by MAP × FiO₂, were the most predictive of death or BPD and NEC, whereas poor neurodevelopmental outcome was associated with low birth weight and IVH. Univariate models also identified PCO₂. Thus, hypercapnia seems to reflect greater disease severity, a likely contributor to differences in outcomes.

Shunts stellen eine therapeutische Option bei intrakranieller Drucksteigerung dar. Diese Arbeit beruht auf den Ergebnissen einer Studie mit 22 Patienten. Analysiert wurden die Blut- und Liquorproben dieser Patienten im Hinblick auf die Veränderung der Nieren- und Eisenparameter sowie die Verteilung des liquor-spezifischen Beta-Trace-Proteins.

Seit jeher fortwährender Bestandteil von kindertraumatologischen Lehrbüchern ist das Paradigma, dass Kinder nach Traumata mit Knochenbruchfolge grundsätzlich keine physikalischen Therapien benötigen. Diese Denkweise spiegelt sich in der gängigen allgemeinen Praxis der Kinderchirurgen wider. Zu der therapeutischen Fragestellung, ob Kinder nach frischen Frakturen eventuell doch eine Rehabilitation benötigen, gestalteten wir eine retrospektive Analyse der in dem Zeitraum von 2008 bis 2013 in der Universitätsklinik für Kinderchirurgie Greifswald behandelten suprakondylären Humerusfrakturen (n = 90), Femurschaftfrakturen (n=40), Kniegelenksverletzungen (n= 34) sowie Tibiaschaftfrakturen (n = 88). Dazu haben wir nach Durchsicht sämtlicher Krankenakten die betroffenen Familien telefonisch anhand eines Fragebogens zu den im Krankenverlauf unternommenen Behandlungen, Therapien und ihren Erfahrungen befragt. Den telefonisch nicht erreichbaren Patienten ist der Fragebogen postalisch mit der Bitte um Beantwortung zugesandt worden. Zur Auswertung der gesammelten Daten haben wir den exakten Test nach Fisher, einen Signifikanztest, herangezogen. Danach ist die Nullhypothese („Routinemäßig angeordnete Rehabilitationsmaßnahmen haben bei Kindern keine Auswirkung auf den Verlauf“) bestätigt worden. Schlussfolgend kann festgehalten werden, dass Physiotherapiemaßnahmen bei Kindern eigentlich nicht notwendig sind. Allerdings kann bei den veränderten sozioökonomischen Umständen mit möglicherweise Hemmung des natürlichen Bewegungsdrangs der Kinder durch Fernsehen und Computerspielen sowie häufig einer Überprotektion durch übervorsichtige Eltern heute nicht selbstverständlicherweise von den natürlichen Zuständen ausgegangen werden, auf denen die Lehrbuchmeinungen beruhen. Von daher halten wir es für empfehlenswert, die Indikationen zur Verordnung von physikalischen Therapien nach Trauma zukünftig großzügiger zu stellen. Eine prospektive wissenschaftliche Evaluation von professionellen und speziell auf die besondere Situation des verletzten Kindes zugeschnittenen Rehabilitationsmaßnahmen wäre sehr vorteilhaft, um die Erkenntnisse von deren positiven Auswirkungen auf den Heilungsverlauf im Ärztekollektiv weiter zu verbreiten und zu stärken.