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Featured researches published by Przemysław Przewratil.


The New England Journal of Medicine | 2015

A Randomized, Controlled Trial of Oral Propranolol in Infantile Hemangioma

Christine Léauté-Labrèze; Peter H. Hoeger; J. Mazereeuw-Hautier; Laurent Guibaud; Eulalia Baselga; Gintas Posiunas; Roderic J Phillips; Héctor Cáceres; Juan Carlos López Gutiérrez; Rosalía Ballona; Sheila Fallon Friedlander; Julie Powell; Danuta Perek; Brandie J. Metz; S. Barbarot; Annabel Maruani; Zsuzsanna Szalai; Alfons Krol; O. Boccara; Regina Foelster-Holst; María Isabel Febrer Bosch; John Su; Hana Buckova; Antonio Torrelo; Frederic Cambazard; Rainer Grantzow; Orli Wargon; Dariusz Wyrzykowski; Jochen Roessler; Jose Bernabeu-Wittel

BACKGROUND Oral propranolol has been used to treat complicated infantile hemangiomas, although data from randomized, controlled trials to inform its use are limited. METHODS We performed a multicenter, randomized, double-blind, adaptive, phase 2-3 trial assessing the efficacy and safety of a pediatric-specific oral propranolol solution in infants 1 to 5 months of age with proliferating infantile hemangioma requiring systemic therapy. Infants were randomly assigned to receive placebo or one of four propranolol regimens (1 or 3 mg of propranolol base per kilogram of body weight per day for 3 or 6 months). A preplanned interim analysis was conducted to identify the regimen to study for the final efficacy analysis. The primary end point was success (complete or nearly complete resolution of the target hemangioma) or failure of trial treatment at week 24, as assessed by independent, centralized, blinded evaluations of standardized photographs. RESULTS Of 460 infants who underwent randomization, 456 received treatment. On the basis of an interim analysis of the first 188 patients who completed 24 weeks of trial treatment, the regimen of 3 mg of propranolol per kilogram per day for 6 months was selected for the final efficacy analysis. The frequency of successful treatment was higher with this regimen than with placebo (60% vs. 4%, P<0.001). A total of 88% of patients who received the selected propranolol regimen showed improvement by week 5, versus 5% of patients who received placebo. A total of 10% of patients in whom treatment with propranolol was successful required systemic retreatment during follow-up. Known adverse events associated with propranolol (hypoglycemia, hypotension, bradycardia, and bronchospasm) occurred infrequently, with no significant difference in frequency between the placebo group and the groups receiving propranolol. CONCLUSIONS This trial showed that propranolol was effective at a dose of 3 mg per kilogram per day for 6 months in the treatment of infantile hemangioma. (Funded by Pierre Fabre Dermatologie; ClinicalTrials.gov number, NCT01056341.).


Cytokine | 2010

LOCAL SERUM LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR IN INFANTILE HEMANGIOMA: INTRIGUING MECHANISM OF ENDOTHELIAL GROWTH

Przemysław Przewratil; Anna Sitkiewicz; Ewa Andrzejewska

UNLABELLED The pathogenesis of hemangiomas still remains poorly understood. Dysregulation of angiogenesis has been proposed to play a central role in hemangioma pathogenesis. The aim of our study was to determine the peripheral and local serum levels of VEGF in patients with hemangiomas and vascular malformations. MATERIAL AND METHODS The study group consisted of 52 children with infantile hemangioma (33 with proliferative lesions, 19 with involuting lesions), 14 children with vascular malformations and 36 healthy children. VEGF serum levels were analyzed by an ELISA assay and the values between the groups were compared. RESULTS The serum peripheral VEGF concentrations in children with proliferative hemangiomas were significantly higher than in patients with involuting hemangiomas, vascular malformations and controls. There was no correlation between the measured cytokine level, hemangioma size, and the age of the patients. The local serum VEGF levels in 29 children with hemangiomas were distinctly lower than in the peripheral blood, both in 20 proliferating hemangiomas (p<0.0001) and 9 involuting ones (p=0.007); and the difference between females and males was non-significant (NS p=0.06). CONCLUSIONS (1) VEGF serum levels vary in the different phases of hemangioma growth and may help to distinguish hemangiomas from vascular malformations; (2) obtained local results may support the intrinsic theory of endothelial cell proliferation in hemangiomas.


Pediatric Dermatology | 2009

SERUM LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR AND BASIC FIBROBLASTIC GROWTH FACTOR IN CHILDREN WITH HEMANGIOMAS AND VASCULAR MALFORMATIONS--PRELIMINARY REPORT

Przemysław Przewratil; Anna Sitkiewicz; Krystyna Wyka; Ewa Andrzejewska

Abstract:  Impaired balance between proangiogenic and antiangiogenic factors has been implicated in the development of hemangiomas. Elevated vascular endothelial growth factor serum levels and basic fibroblastic growth factor urine levels in patients with proliferating hemangiomas were reported. However, whether these growth factors can be used for the differential diagnosis of vascular anomalies or assessment of the clinical course of hemangiomas has yet to be determined. We report here our preliminary results of serum vascular endothelial growth factor and basic fibroblastic growth factor levels as an aid in the diagnosis of hemangiomas and in the follow up of patients with this lesion. Twenty two children with infantile hemangioma (13 with proliferating hemangiomas, nine with involuting lesions), five children with vascular malformations, and 25 healthy children study group. Vascular endothelial growth factor and basic fibroblastic growth factor serum levels were analyzed by an ELISA assay. The serum vascular endothelial growth factor concentrations in children with proliferating hemangiomas were significantly higher than in patients with involuting hemangiomas, vascular malformations and healthy patients. The serum basic fibroblastic growth factor concentrations were low and similar in all patients with no statistical correlation between study groups. We concluded that (i) ELISA can easily determine vascular endothelial growth factor concentrations in different phases of hemangioma growth and help distinguishing them from vascular malformations. (ii) A potential role for vascular endothelial growth factor in the pathophysiology of hemangiomas is probable.


Immunology Letters | 2017

Molecular and immunohistochemical expression of apoptotic proteins Bax, Bcl-2 and Caspase 3 in infantile hemangioma tissues as an effect of propranolol treatment

Aneta Wnęk; Ewa Andrzejewska; Józef Kobos; Katarzyna Taran; Przemysław Przewratil

BACKGROUND Infantile hemangiomas (IHs) are the most common benign tumors of childhood. They are characterized by a unique clinical course with two phases, proliferation and involution, which are followed by regression. The therapy of infantile hemangiomas was revolutionized in 2008 by the introduction of propranolol, however, the mechanism of its influence on hemangiomas remains unclear. METHODS The study included 71 patients with IHs, 27 of whom were treated with propranolol while the remaining 44 were used as a comparative group. The expression of Bcl-2, Bax and Caspase3 was determined with immunohistochemistry and mRNA of Bax, Bcl-2 and Caspase3 were assessed with the use of RT-PCR. RESULTS Both methods revealed a statistically significant decrease in Bcl-2 expression and an increase in Bax in IHs tissues after propranolol treatment. CONCLUSIONS The results obtained for Bax and Bcl-2 proteins may indicate a link between the effect of propranolol and apoptosis. Higher Bax and lower Bcl-2 expression in the propranolol treated group indicates a strong pro- apoptotic action countering any anti-apoptotic activity; apoptosis was indicted in IH tissue as a potential result of propranolol treatment, with potential clinical impact in other tumors.


Immunology Letters | 2016

Serum and tissue profile of VEGF and its receptors VGFR1/R2 in children with infantile hemangiomas on systemic propranolol treatment

Przemysław Przewratil; Józef Kobos; Aneta Wnęk; Janusz Szemraj; Dariusz Wyrzykowski; Barbara Chrzanowska; Ewa Andrzejewska; Katarzyna Taran

UNLABELLED In the last few years propranolol has revolutionized infantile hemangioma therapy. This nonselective β bloker has been proven to be safe and effective but the molecular bases of its actions remain unclear. One of debated theories holds that propranolol may inhibit angiogenesis and induce apoptosis. To investigate this claim, this study aims to analyze the serum and tissue profiles of VEGF and VEGRR1/2 in patients treated with propranolol. MATERIALS AND METHODS To assess the expression if VEGF and VEGRR1/2 we used three independent methods. First we analyzed serum VEGF levels in 50 children with IH before and 3 months after the therapy using ELISA test (I.). Then we used immunohistochemistry to evaluate tissue expression of VEGF and VEGFR1/2 in IH treated (n=27) and not treated (n=45) with propranolol (II.). Finally we assessed mRNA of VEGF and VEGFR1/2 in the same patients as in part II (III.). RESULTS (I) There was no distinct decrease of VEGF level in children with IH after propranolol treatment. (II) We found no significant difference in VEGFR1 and VEGFR2 expression in hemangiomas from the study and control group. The expression of VEGF was even higher than before therapy. (III) VEGF and VEGFR1 mRNA expression was significantly lower in IH tissue after propranolol treatment compared to those without treatment. VEGFR2 demonstrated no differences in expression between the two groups. CONCLUSIONS The obtained results show distinct discrepancies between in vitro and clinical studies as well as among different methods used for analyzing the same phenomenon. Only VEGF and VEGFR1 expression in mRNA studies may prove the proposed theory of antiangiogenic properties of propranolol. Other results do not confirm it and remain inconsistent with the fantastic clinical response to this medication.


Growth Factors Journal | 2010

Soluble receptors for vascular endothelial growth factor (sVEGFR1/sVEGFR2) in infantile hemangioma

Przemysław Przewratil; Anna Sitkiewicz; Ewa Andrzejewska

Vascular endothelial growth factor (VEGF) and its receptors were postulated to be involved in pathogenesis of infantile hemangioma. The aim of this study was to determine the serum levels of VEGF and soluble VEGF receptors (sVEGFR1/sVEGFR2) in children with hemangiomas. Materials and methods: Thirty-eight children with infantile hemangiomas (25 proliferating, 13 involuting) and 34 healthy children were included in the study. sVEGFR1 and sVEGFR2 serum levels in peripheral blood and in vascular tumors were determined with ELISA test. Results: sVEGFR1 serum levels were slightly lower in hemangioma patients (p = 0.049). No significant differences in sVEGFR2 levels were observed in any study group. VEGF levels did differ significantly, with median level being 364.05 pg/ml in hemangioma patients and 107.40 pg/ml in the control group (p < 0.0001). Conclusions: The obtained results suggest that VEGF is involved in hemangioma angiogenesis but that soluble VEGFRs marginally influence this process. Lower serum levels of sVEGFR1 in hemangioma patients indicate the possible dysregulation between VEGFR1 and VEGFR2 receptors.


Polish Journal of Radiology | 2015

The Role of Ultrasound Imaging of Callus Formation in the Treatment of Long Bone Fractures in Children.

Magdalena Wawrzyk; Jan Sokal; Ewa Andrzejewska; Przemysław Przewratil

Summary Background In the process of diagnosis and treatment of fractures, an X-ray study is typically performed. In modern medicine very important is the development of new diagnostic methods without adverse effects on the body. One of such techniques is ultrasound imaging. It has a high value in imaging most areas of the body, including the musculoskeletal system. Reports on the use of ultrasound in the evaluation of the callus are rare and this could be a method equivalent to or even better than standard radiographs. The aim of the study was to analyze the correlation of ultrasound with radiographs in imaging of callus formation after fractures of long bones in children and to analyze the correlation of vascular resistance index (RI) and the degree of vascularization of the callus with a subjective radiological assessment of the bone union quality. Material/Methods The prospective study was planned to qualify 50 children treated for long bones fractures of the arm, forearm, thigh and lower leg. Ultrasound diagnosis was carried out using a Philips iU22 camera equipped with a linear probe with 17-5-MHz resolution and MSK Superficial program. During ultrasound examination measurements of the callus were performed. Using the Power Doppler callus vascularity was visualized and vascular resistance index (RI) was measured. The same measurements were made within the corresponding area of the healthy limb. The results obtained by ultrasound were compared with radiograph measurements and with the subjective assessment of the callus quality. Results Preliminary results were developed on a group of 24 patients, where 28 fractured bones and 28 corresponding healthy bones were examined. Fifteen boys and 9 girls participated in the study. The average age at injury was, respectively, 11 and 9 years. In both groups fractures without displacement were the most frequent. A similar frequency was observed in fractures requiring reposition and subperiosteal fractures. In contrast, fractures with a slight displacement of the fragments, were 3 times more common in girls. Statistical analysis of the measurements of length and width of the callus demonstrated that the differences between results obtained in the ultrasound in comparison with X-rays were not statistically significant. Moreover, preliminary results showed a significantly higher degree of vascularization of the callus than of the healthy periosteum. Conclusions Preliminary results indicate the high efficacy of ultrasound in the evaluation of callus formation after fractures of long bones in children and the possibility of its alternative use to X-ray examinations.


Pediatrics | 2018

Efficacy of Propranolol Between 6 and 12 Months of Age in High-Risk Infantile Hemangioma

Eulalia Baselga; Bożenna Dembowska-Bagińska; Przemysław Przewratil; Maria Antonia González-Enseñat; Dariusz Wyrzykowski; Antonio Torrelo; Juan-Carlos López Gutiérrez; Magdalena Rychłowska-Pruszyńska; Raúl de Lucas-Laguna; A. Esteve-Martínez; Esther Roé; Mohammed Zaim; Yoann Menon; Stéphanie Gautier; Geneviève Lebbé; Athmane Bouroubi; Alain Delarue; Jean-Jacques Voisard

Extending propranolol treatment beyond 6 months up to 12 months of age produces a meaningful increase in the high-risk IH success rate. BACKGROUND AND OBJECTIVES: There is no consensus on optimal treatment duration for propranolol in infantile hemangioma (IH). We evaluated the efficacy and safety of oral propranolol solution administered for a minimum of 6 months up to a maximum of 12 months of age in high-risk IH. METHODS: This single-arm, open-label, phase 3 study was conducted in patients aged 35 to 150 days with high-risk IH in 10 hospitals between 2015 and 2017. The study comprised a 6-month initial treatment period (ITP) plus continuation up to 12 months of age if complete success was not achieved, a follow-up, and a retreatment period. Patients received oral propranolol twice daily (3 mg/kg per day). The primary end point was the success rate at the end of the ITP. Furthermore, the persistence of IH response and efficacy of retreatment was evaluated. RESULTS: The success rate after 6 months of treatment was 47%, increasing to 76% at the end of the ITP. Of the patients who achieved success, 68% sustained success for 3 months without treatment, and 24% required retreatment. Of the 8 patients who were retreated, 7 achieved success. Adverse events, reported by 80% of patients, were mild, which were expected in this population or known propranolol side effects. CONCLUSIONS: Oral propranolol administered beyond 6 months and up to 12 months of age meaningfully increases the success rate in high-risk IH. Success was sustained in most patients up to 3 months after stopping treatment. Retreatment was efficacious, and the safety profile satisfactory.


International Journal of Dermatology | 2018

Single-nucleotide polymorphisms of VEGF-A and VEGFR-2 genes and risk of infantile hemangioma

Katarzyna Oszajca; Janusz Szemraj; Dariusz Wyrzykowski; Barbara Chrzanowska; Aneta Salamon; Przemysław Przewratil

Infantile hemangioma (IH) is the most common vascular tumor of childhood and infancy. It is distinguished by rapid proliferation of endothelial cells during the first year of life followed by spontaneous regression thereafter. One of the possible factors responsible for the IH development is vascular endothelial grow factor (VEGF). The purpose of this study was to evaluate the influence of selected polymorphisms in the genes coding for VEGF‐A (+405 G/C, rs2010963; +936 C/T, rs3025039) and its receptor VEGFR‐2 (+1416 T/A, rs1870377; –271 G/A, rs7667298) on the susceptibility to infantile hemangioma.


Clinical Biochemistry | 2010

Serum levels of basic fibroblastic growth factor (bFGF) in children with vascular anomalies: Another insight into endothelial growth

Przemysław Przewratil; Anna Sitkiewicz; Ewa Andrzejewska

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Ewa Andrzejewska

Medical University of Łódź

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Józef Kobos

Medical University of Łódź

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Aneta Wnęk

Medical University of Łódź

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Anna Sitkiewicz

Medical University of Łódź

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Katarzyna Taran

Medical University of Łódź

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Janusz Szemraj

Medical University of Łódź

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Jerzy Niedzielski

Medical University of Łódź

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Eulalia Baselga

Autonomous University of Barcelona

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Aneta Salamon

Medical University of Łódź

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Darius A. Paduch

Medical University of Łódź

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