Necrotizing enterocolitis after intravitreal bevacizumab in an infant with Incontinentia Pigmenti - a case report.

BACKGROUND: Incontinentia Pigmenti is a rare disease affecting multiple organs. Fifty of patients show affection of the eye with retinopathy and possible amaurosis being the worst outcome. Treatment has commonly been panretinal laser coagulation but intravitreal application of bevacizumab as VEGF-inhibitor has shown to effectively suppress retinal neovascularization. CASE PRESENTATION: A six-week-old female infant with Incontinentia Pigmenti developed a foudroyant necrotizing enterocolitis shortly after intravitreal injection of bevazicumab due to a retinopathy with impending tractional detachment of the left eye. Since the onset of abdominal symptoms occurred immediately after the intravitreal application, a link between the two events seemed likely. Sequential analyses of the VEGF serum concentrations showed a massive suppression of endogenous VEGF with only a very slow recovery over weeks. Such a severe systemic adverse event has not been reported after intravitreal treatment with bevacizumab in an infant. CONCLUSION: This case report shows a relevant systemic uptake of bevacizumab after intravitreal application as suppressed VEGF levels show. There seems to be a connection between suppressed VEGF levels and the onset of necrotizing enterocolitis. Therefore, treatment with bevacizumab should be carefully considered and further research is needed to assess this drug's safety profile.

[The Lymphoid Variant of HES (L-HES) as Differential Diagnose of Severe Asthma in Childhood]. / Ein T-Zell assoziiertes Hypereosinophilie-Syndrom (L-HES) als Differenzialdiagnose eines Asthma bronchiale.

Based on a case report an overview on the differential diagnostic considerations with respect to blood hypereosinophilia (HE) and hypereosinophilic syndromes (HES) in childhood is given. A 13-year-old boy was admitted for the clarification of an asthma. In the blood count an increased HE with 3 500/µl (30%) was found along with elevated total serum IgE and IL-5 level (2 000 IU/ml and 17 pg/ml). Lung function showed an obstruction (FEV1 38%). Radiologically the picture of bronchiectasis and mucus pluggine appeared. In the BAL a HE (76%) with raised IL-5 level was apparent. Histologically asthma was diagnosed with mucostasis, hypertrophy of the bronchial wall musculature and a lung HE. Differential-diagnostically an ABPA, a Churg-Strauss-Syndrome, a parasitosis, drug associated HE, allergies and malignant disease could be excluded. An aberrant T-cell clone in peripheral blood was detected by flow cytometry and T-cell receptor clonal rearrangements by PCR, leading to the diagnosis of a lymphoid variant of HES (L-HES). Failure to detect the FIP1L1-PDGFRA gene fusion and a normal bone marrow examination could exclude a neoplastic HES (HESN). After steroid initiation, prompt decrease of blood eosinophilia with resolution of symptoms was observed. Steroid discontinuation led to eosinophilia recurrence associated with disease symptoms. As steroid-sparing agent the immunosuppressive azathioprine was additionally given; steroid doses could be decreased and stopped in the course. This case demonstrated the range of HE evaluation in infancy. With asthma one should also consider the possibility of a L-HES.

[The Hypereosinophilic Syndromes in Childhood]. / Die Hypereosinophilie-Syndrome (HES) im Kindesalter.

The hypereosinophilic syndromes are rare disorders in childhood and require extensive differential diagnostic considerations. In the last years the earlier "idiopathic HES" called syndromes could be differentiated into molecular biologically, immunophenotypically and clinically more characterized heterogeneous diseases with high therapeutic and prognostic relevance. Nowadays the term HES summarizes diseases, which go hand in hand with a local or systemic hypereosinophilia (HE) connected with an organ damage. Depending on the cause of the HE one differentiates primary/neoplastic HES (HESN) from secondary/reactive HES (HESR). The latter develops reactively in connection with allergies, parasitosis, medications, neoplasia or a clonal increase of T-lymphocytes among others. With HESN the HE results from a clonal increase of eosinophilic granulocytes. While for some subgroups of the HESN (among others FIP1L1-PDGFRA fusion gene) the administration of a tyrosine kinase inhibitor is a new and effective therapy option, glucocorticoids still represent the medication of first choice for many not PDGFRA associated variants. Different immunomodulatory drugs or cytostatic agents are necessary to allow dose reduction of glucocorticoids. The promising therapy with anti-IL-5 antibodies is still not approved in infancy, could however become a treatment option in the future. Due to the present lack of knowledge about the HES in infancy the establishment of a register should be aimed for the treatment of HES in infancy.

Compound heterozygosity of two functional null mutations in the ALPL gene associated with deleterious neurological outcome in an infant with hypophosphatasia.

Hypophosphatasia (HPP) is a heterogeneous rare, inherited disorder of bone and mineral metabolism caused by different mutations in the ALPL gene encoding the isoenzyme, tissue-nonspecific alkaline phosphatase (TNAP). Prognosis is very poor in severe perinatal forms with most patients dying from pulmonary complications of their skeletal disease. TNAP deficiency, however, may also result in neurological symptoms such as neonatal seizures. The exact biological role of TNAP in the human brain is still not known and the pathophysiology of neurological symptoms due to TNAP deficiency in HPP is not understood in detail. In this report, we describe the clinical features and functional studies of a patient with severe perinatal HPP which presented with rapidly progressive encephalopathy caused by new compound heterozygous mutations in the ALPL gene which result in a functional ALPL "knock out", demonstrated in vitro. In contrast, an in vitro simulation of the genetic status of his currently asymptomatic parents who are both heterozygous for one mutation, showed a residual in vitro AP activity of above 50%. Interestingly, in our patient, the fatal outcome was due to progressive encephalopathy which was refractory to antiepileptic therapy including pyridoxine, rather than hypomineralization and respiratory insufficiency often seen in HPP patients. The patient's cranial MRI showed progressive cystic degradation of the cortex and peripheral white matter with nearly complete destruction of the cerebrum. To our knowledge, this is the first MRI-based report of a deleterious neurological clinical outcome due to a progressive encephalopathy in an infant harboring a functional human ALPL "knock out". This clinical course of disease suggests that TNAP is involved in development and may be responsible for multiple functions of the human brain. According to our data, a certain amount of residual TNAP activity might be mandatory for normal CNS function in newborns and early childhood.

[Effects of antenatal inflammation on the developing lung]. / Pathogenetische Effekte der prä- und postnatalen Inflammationsreaktion in den Lungen.

The developing lung and immune systems are very plastic and their developmental pathway can be influenced by various endogenous and/or exogenous factors. In the last years translational research with various animal models has been helpful to answer some basic questions about the effect of chorioamnionitis on maturation and development of the foetal lung and immune system. Chorioamnionitis can induce a cascade of lung injury, pulmonary inflammation and remodelling in the foetal lung. Chorioamnionitis-induced IL-1 production is consistently associated with lung maturation, induced by enhancing surfactant protein and lipid synthesis. IL-1 therefore seems to be the main link between lung inflammation and lung maturation, which largely prevents RDS in preterm infants. On the other hand, chorioamnionitis can also cause structural lung changes and affect the expression of growth factors, like TGF-ß, CTGF, FGF-10 or BMP-4, which are crucial for branching morphogenesis. These changes result in alveolar and microvascular simplification similar to BPD. Neonatal outcome may also be affected by chorioamnionitis by modulating the efficacy of the immune system. Chorioamnionitis can induce LPS-tolerance (endotoxin hyporesponsiveness/immunoparalysis), which may prevent further foetal lung damage but increases susceptibility to postnatal infections. The inflammatory and developmental signalling pathways affected by chorioamnionitis form delicately regulated networks, which interact with each other to control lung development. In addition to chorioamnionitis, these pathways can be affected by other prenatal (steroid) or postnatal factors (mechanical ventilation, oxygen exposure, infection, steroids). Because the postnatal response to injury appears to be highly dependent on prenatal exposures, the "secondary hit" hypothesis is very plausible, in which exposure to chorioamnionitis is a predisposition for the development of adverse neonatal outcomes.

Immune-mediated severe hemolytic crisis with a hemoglobin level of 1.6 g/dl caused by anti-piperacillin antibodies in a patient with cystic fibrosis.

We report a 23-year-old female patient with cystic fibrosis developing severe intravascular hemolysis with a minimal hemoglobin level of 1.6 g/dl after 7 days of treatment with piperacillin, consistent with an immune-mediated hemolytic crisis. Twenty days later, the patient could leave the hospital in good condition without any neurological deficit. To our knowledge, this is the lowest reported hemoglobin value caused by hemolytic anemia with intact survival. As piperacillin is commonly used in patients with cystic fibrosis, it is important to monitor the full-blood counts of patients during treatment with piperacillin and to be aware of the potential for hemolytic anemia to develop. Anti-piperacillin antibodies should be considered whenever these patients develop hemolytic anemia or a positive direct antiglobulin test (DAT). Furthermore, drug-fever under piperacillin application could be a warning sign for the development of hemolytic anemia.

Connective tissue growth factor does not affect transforming growth factor-beta 1-induced Smad3 phosphorylation and T lymphocyte proliferation inhibition.

Transforming growth factor-beta 1 (TGF-beta(1)) is a key regulator of immune tolerance. TGF-beta(1) controls T lymphocyte activation and is involved in the immunosuppressive function and generation of regulatory T lymphocytes. Connective tissue growth factor (CTGF) has an essential role in the formation of connective tissue and blood vessels. CTGF expression is induced by TGF-beta(1) in several cell types and CTGF mediates several of the downstream actions of TGF-beta(1). Since little is known about the potential synergy between CTGF and TGF-beta(1) in T lymphocyte biology, the purpose of the present study was to determine whether CTGF can modulate TGF-beta(1)-mediated effects on human CD4+ T lymphocytes. Human recombinant CTGF was expressed in HEK293 cells. rCTGF was biologically active demonstrated by induction of proliferation in the endothelial cell line EA hy 926. rCTGF alone did not potentiate or diminish anti-CD3-induced CD4+ T lymphocyte proliferation and did not activate the Smad signaling pathway in CD4+ T lymphocytes. Furthermore, rCTGF did not attenuate TGF-beta(1)-mediated inhibition of CD4+ T lymphocyte proliferation and TGF-beta(1)-induced Smad signaling in CD4+ T lymphocytes. These results indicate that rCTGF had no detectable effects of its own on human CD4+ T lymphocytes and did not potentiate the effects of low amounts of TGF-beta(1) on human CD4+ T lymphocytes. Overall, these data support the hypothesis that CTGF does not act on CD4+ T lymphocytes.

Histamine enhances TGF-beta1-mediated suppression of Th2 responses.

Susceptibility of T cells to TGF-beta1 produced by regulatory T cells has an important impact on the induction and maintenance of peripheral tolerance and therefore on the development of autoimmunity, cancer, and allergy. Histamine not only mediates the deleterious effects of allergic reactions, it can also modulate the Th1/Th2 cell balance. We demonstrate that histamine dose-dependently enhanced TGF-beta1-mediated suppression and TGF-beta1 responsiveness of CD4+ T cells. This effect was mediated by the histamine 2 receptor (H2R), as demonstrated by receptor-specific agonists and antagonists. Furthermore, the histamine effect on TGF-beta1 responsiveness was cAMP/PKA dependent. This pathway is activated by the H2R, which is preferentially expressed on Th2 cells. Thus a higher additive effect of histamine on TGF-beta1 responsiveness was found in Th2 cells compared with Th1 cells. In fact, findings are confirmed by analysis of cytokine regulation, since activation of the H2R/cAMP pathway promoted TGF-beta1-mediated IL-4 inhibition but was ineffective in suppressing IFN-gamma. These results demonstrate that histamine supports TGF-beta1 susceptibility of T cells. Moreover, Th2 cells are more affected by histamine-enhanced TGF-beta1 suppression, which is particularly important for the regulation of allergen-specific T cells in allergic immune responses.

SARA and Hgs attenuate susceptibility to TGF-beta1-mediated T cell suppression.

Transforming growth factor-beta1 (TGF-beta1) is a pluripotent cytokine that controls peripheral T cell tolerance mainly in mucosal immunity. It is secreted by regulatory T cells (Tr /Th3) but also by other immununologically active cells. Smad anchor for receptor activation (SARA) and hepatic growth factor-regulated tyrosine kinase substrate (Hgs) are involved in TGF-beta1 signaling. Both molecules are known to present Smad2 and Smad3 to the TGF-beta receptor complex. The role of SARA and Hgs in TGF-beta1 susceptibility of human CD4+ T cells is unclear. We demonstrate here that TGF-beta1 up-regulates SARA mRNA expression in CD4+ T cells similar to that of Smad7. However, the increase in SARA expression was lower (6.1+/-0.3-fold vs. 25+/-4.1-fold) compared with Smad7 and delayed, with a maximum at 12 h compared with 2 h. Th1 and Th2 cell subsets expressed the same levels of SARA and Hgs. Compared with resting cells, significantly lower levels of the two molecules were found in antigen/allergen- or anti-CD3/CD28-stimulated cells. Down-regulation of SARA and Hgs mRNA in preactivated CD4+ T cells was accompanied by a twofold increase in a TGF-beta1 responsive reporter gene assay. Overexpression of SARA and Hgs in T cells yielded a dose-dependent decrease in cotransfected reporter gene expression, indicating an inhibitory function of both molecules. Thus, SARA and Hgs are regulators of TGF-beta1 susceptibility in T cells and integrate regulatory signals into the influence of TGF-beta1-mediated suppression of human T cells.

A murine interleukin-4 antagonistic mutant protein completely inhibits interleukin-4-induced cell proliferation, differentiation, and signal transduction.

We characterize here a highly efficient antagonist for interleukin-4 (IL-4) in the mouse system. In this double mutant of the murine IL-4 protein, both glutamine 116 and tyrosine 119 were substituted by aspartic acid residues. This variant (QY) bound with similar affinity to the IL-4 receptor alpha subunit as wild type IL-4 without inducing cellular responses. In contrast, QY completely inhibited in a dose-dependent manner the IL-4-induced proliferation of lipopolysaccharide-stimulated murine splenic B-cells, of the murine T cell line CTLL-2, and of the murine pre-B-cell line BA/F3. QY also inhibited the IL-4-stimulated up-regulation of CD23 expression by lipopolysaccharide-stimulated murine splenic B-cells and abolished tyrosine phosphorylation of the transcription factor Stat6 and the tyrosine kinase Jak3 in IL-4-stimulated BA/F3 cells. Selective inhibition of IL-4 may be beneficial in T-helper cell type 2-dominated diseases, like type I hypersensitivity reactions or helminthic infections. The QY mutant could be an attractive tool to study in vivo the therapeutic potential of IL-4 antagonists in mouse systems.

[Computer-assisted speech recognition and display of x-ray findings]. / Computergestützte Spracherkennung und Ausdruck von Röntgenbefunden.

A voice recognition system, called Tangora, has been designed for the German language; its prototype has been tested to assess its clinical usefulness for radiological reporting. Its technical vocabulary consists of 20,000 words. The system recognises words spoken provided short pauses are inserted. The Tangora system was compared with conventional methods of dictation, using 68 radiological reports. The work necessary for each system was analysed. The average time taken by the Tangora system per report was 671 seconds compared with 182 seconds for conventional dictation but improvements in the speed of the new system for radiological reporting is to be expected.