Pediatric vascular anomalies in Austria. Where are we at? A survey among primary care pediatricians.

Introduction: Vascular anomalies (VAs) are rare conditions and affected patients often experience a difficult patient journey. Timely diagnosis is only possible if primary caregivers are aware of the anomalies and are connected with dedicated specialists. Aim of our survey was to investigate the knowledge about diagnostic and therapeutic possibilities for children with VAs, and the existing networking among primary pediatric caregivers in Austria. Methods: Primary care pediatricians in Austria were invited to complete an online questionnaire consisting of 28 questions focusing on pediatric VAs. Results: Out of 373 invited pediatricians 93 (25%) returned the questionnaires, 86 of which were complete. Most physicians (39/93 42%) answered that they see between 15 and 30 patients with infantile hemangiomas per year. Vascular malformations are rarely treated in the primary care setting; most primary care pediatricians (58/86, 67%) reported that they currently treat fewer than 5 patients with such type of VAs. There was unequivocal agreement among the participants (84/86, 98%) on the need to establish a network of specialists and a registry dedicated to pediatric VAs. Conclusions: This survey represents the first study shedding light on the awareness of VAs among Austrian pediatricians and can serve as a basis for future investigations and advances in the management of these conditions in Austria and other countries with a similar healthcare setting.

The VASCERN-VASCA Working Group Diagnostic and Management Pathways for Venous Malformations.

To elaborate expert consensus patient pathways to guide patients and physicians toward efficient diagnostics and management of patients with venous malformations. Methods: VASCERN-VASCA (https://vascern.eu/) is a European network of multidisciplinary centers for Vascular Anomalies. The Nominal Group Technique was used to establish the pathways. Two facilitators were identified: one to propose initial discussion points and draw the pathways, and another to chair the discussion. A dermatologist (AD) was chosen as first facilitator due to her specific clinical and research experience. The draft was subsequently discussed within VASCERN-VASCA monthly virtual meetings and annual face-to-face meetings. Results: The Pathway starts from the clinical suspicion of a venous type malformation (VM) and lists the clinical characteristics to look for to support this suspicion. Strategies for subsequent imaging and histopathology are suggested. These aim to inform on the diagnosis and to separate the patients into 4 subtypes: (1) sporadic single VMs or (2) multifocal, (3) familial, multifocal, and (4) combined and/or syndromic VMs. The management of each type is detailed in subsequent pages of the pathway, which are color coded to identify sections on (1) clinical evaluations, (2) investigations, (3) treatments, and (4) associated genes. Actions relevant to all types are marked in separate boxes, including when imaging is recommended. When definite diagnoses have been reached, the pathway also points toward disease-specific additional investigations and recommendations for follow up. Options for management are discussed for each subtype, including conservative and invasive treatments, as well as novel molecular therapies. Conclusion: The collaborative efforts of VASCERN-VASCA, a network of the 9 Expert Centers, has led to a consensus Diagnostic and Management Pathways for VMs to assist clinicians and patients. It also emphasizes the role of multidisciplinary expert centers in the management of VM patients. This pathway will become available on the VASCERN website (http://vascern.eu/).

The epifascial cap: A typical imaging sign for subcutaneous granuloma annulare in children.

Objectives: Subcutaneous granuloma annulare (SGA) is a rare, self-limiting granulomatous disease in children, commonly diagnosed by histopathology following biopsy or surgical excision. This study aimed to identify imaging clues for SGA that could expedite accurate diagnosis and avoid the need for biopsy in children. Methods: We retrospectively analyzed complete hospital records of all children diagnosed with SGA at our institution from January 2001 to December 2020. Detailed disease history, imaging findings, management, and outcome were evaluated. Results: We identified 28 patients (20 girls) at a median age of 3.75 (range 1-12.5 years). Ten patients presented with multiple lesions. Most lesions were located on the lower extremities (n = 26/41). Ultrasound examinations were performed on all patients, and 12 (43%) patients also received an MRI. Surgical intervention was conducted in 18 (64%) patients either by incisional biopsy (n = 6) or total excision of the lump (n = 12). In all patients who did not undergo surgery, SGA resolved spontaneously. A careful review of the MRIs led to the discovery of a characteristic imaging shape of SGA lesions: the epifascial cap with a typical broad circular base laying on the fascia, extending towards the subdermal/dermal tissue. This distinctive shape was evident in every patient in our cohort. Conclusions: The "Epifascial Cap Sign" is a specific imaging sign for SGA, which to the best of our knowledge, helps distinguish this disease from other subcutaneous lesions. Recognition of this novel diagnostic sign combined with the historical and physical findings should enable clinicians to establish SGA diagnosis easily and diminish the need for further invasive diagnostic procedures.

Indications for surgical resection of complicated infantile hemangiomas in the ß-blocker's era: a single-institution experience from a retrospective cohort study.

BACKGROUND AND OBJECTIVES: This study aims to review how the introduction of propranolol as the primary treatment option for children with infantile hemangiomas (IHs) has affected the use of other treatment options at our institution and to determine the indications for surgical treatment of children with IHs in the propranolol era. PATIENTS AND METHODS: The authors conducted a single-center, noncompeting, historical/retrospective cohort study to review all cases referred to the institution for IH evaluation from 2005 to 2020. The authors analyzed the complete charts of patients who received surgery from 2011 to 2020 and evaluated the reasons for each surgical intervention. Detailed descriptive statistics are provided. Logistic regression analysis and Pearson's χ2 -test were applied. RESULTS: During the study period, 592 children received treatment. From 2011, oral propranolol ( n =268; 74%) and surgery ( n =95; 26%) were the only treatments of choice for complicated IH cases. A significant decrease in the frequency of surgical treatment was observed ( P =0.01). The authors identified four main indications for surgical treatment: (1) patients with ulceration and IH size appropriate for surgical resection (15%); (2) patients whose parents preferred surgical treatment (19%); (3) patients who presented late and underwent surgery before the age of three (29%); and (4) patients with sequelae after IH involution and excision after the third year of life (37%). CONCLUSIONS: Despite the significant decrease in the need for surgical treatment of children with IHs since the introduction of propranolol, there are still several clear indications for treating IH cases where surgery plays a crucial role.

Outcome after surgical treatment of venous malformations of the hand in childhood.

OBJECTIVE: Surgical treatment of venous malformations (VMs) of the hand is challenging. The hand's small functional units, dense innervation, and terminal vasculature can be easily compromised during invasive interventions like surgery or sclerotherapy, leading to an increased risk of functional impairment, cosmetic consequences, and negative psychological effects. METHODS: We have conducted a retrospective review of all surgically treated patients diagnosed with VMs of the hand between 2000 and 2019 and evaluated their symptoms, diagnostic investigations, complications, and recurrences. RESULTS: Twenty-nine patients (females, n = 15) with a median age of 9.9 years (range, 0.6-18 years) were included. Eleven patients presented with VMs involving at least one of the fingers. In 16 patients, the palm and/or dorsum of the hand was affected. Two children presented with multifocal lesions. All patients presented with swelling. Preoperative imaging was done in 26 patients and consisted of magnetic resonance imaging in nine patients, ultrasound in eight patients, and both modalities in nine patients. Three patients underwent surgical resection of the lesions without any imaging. Indications for surgery were pain and restriction of function (n = 16), and when lesions were preoperatively evaluated as completely resectable (n = 11). In 17 patients, a complete surgical resection of the VMs was performed, whereas in 12 children, an incomplete resection of VM was deemed due to nerve sheath infiltration. At a median follow-up of 135 months (interquartile range, 136.5 months; range, 36-253 months), recurrence occurred in 11 patients (37.9%) after a median time of 22 months (range, 2-36 months). Eight patients (27.6%) were reoperated because of pain, whereas three patients were treated conservatively. The rate of recurrences did not significantly differ between patients presenting with (n = 7 of 12) or without (n = 4 of 17) local nerve infiltration (P = .119). All surgically treated patients who were diagnosed without preoperative imaging developed a relapse. CONCLUSIONS: VMs in the region of the hand are difficult to treat, and surgery is associated with a high recurrence rate. Accurate diagnostic imaging and meticulous surgery may contribute to improve the outcome of the patients.

Subcutaneous Granuloma Annulare vs. Subcutaneous Vascular Malformations in Children: A Diagnostic Challenge.

OBJECTIVES: There are various subcutaneous lesions in children and often there is difficulty in obtaining an accurate diagnosis by non-invasive diagnostic procedures. Subcutaneous granuloma annulare (SGA) is a rare granulomatous disease that, even after imaging, is often mistaken for a low-flow subcutaneous vascular malformation (SVM). This study aimed to accurately identify clinical and imaging clues to distinguish SGA from low-flow SVM. METHODS: We retrospectively analyzed complete hospital records of all children with a confirmed diagnosis of SGA and low-flow SVM who underwent MR imaging at our institution from January 2001 to December 2020. Their disease history, clinical and imaging findings, management, and outcome were evaluated. RESULTS: Among 57 patients with granuloma annulare, we identified 12 patients (nine girls) with a confirmed SGA diagnosis who underwent a preoperative MRI. Their median age was 3.25 years (range 2-5 years). Of 455 patients diagnosed with vascular malformations, 90 had malformations limited to the subcutaneous area. Among them only 47 patients with low-flow SVM were included in the study and further analyzed. Our SGA cohort had a female predilection (75%) and a short history of lump appearance of 1.5 months. SGA lesions were immobile and firm. Before MRI, patients underwent initial evaluation by ultrasound (100%) and X-ray (50%). Surgical tissue sampling was performed in all SGA patients to establish a diagnosis. All 47 patients with low-flow SVM were diagnosed correctly by MRI. A total of 45 patients (96%) underwent surgical resection of the SVM. A careful retrospective review of imaging findings of patients with SGA and SVM showed that SGA present as homogenous lesions in the shape of an epifascial cap with a typical broad fascial base extending towards the subdermal tissue in the middle of the lesion. In contrast, SVMs always present with variable-sized multicystic or tubular areas. CONCLUSIONS: Our study shows clear clinical and imaging differences between low-flow SVMs and SGA. SGA presents characteristically in the shape of a homogenous "epifascial cap," which distinguishes these lesions from multicystic heterogenous SVMs.

The VASCERN-VASCA working group diagnostic and management pathways for lymphatic malformations.

Lymphatic malformations (LMs) are developmental defects of lymphatic vessels. LMs are histologically benign lesions, however, due to localization, size, and unexpected swelling, they may cause serious complications that threaten vital functions such as compression of the airways. A large swelling of the face or neck may also be disfiguring and thus constitute a psychological strain for patients and their families. LMs are also highly immunologically reactive, and are prone to recurrent infections and inflammation causing pain as well as chronic oozing wounds. The European Reference Network on Rare Multisystemic Vascular Diseases (VASCERN) is dedicated to gathering the best expertise in Europe. There are only few available guidelines on management and follow up of LMs, which commonly focus on very specific situations, such as head and neck LM (Zhou et al., 2011). It is still unclear, what constitutes an indication for treatment of LMs and how to follow up the patients. The Vascular Anomalies Working Group (VASCA-WG) of VASCERN decided to develop a diagnostic and management pathway for the management of LMs with a Nominal Group Technique (NGT), a well-established, structured, multistep, facilitated group meeting technique used to generate consensus statements. The pathway was drawn following 2 face-to-face meetings and multiple web meetings to facilitate discussion, and by mail to avoid the influence of most authoritative members. The VASCA-WG has produced this opinion statement reflecting strategies developed by experts and patient representatives on how to approach patients with lymphatic malformations in a practical manner; we present an algorithmic view of the results of our work.

Indications and Limitations of Sirolimus in the Treatment of Vascular Anomalies-Insights From a Retrospective Case Series.

Background: Despite recent developments, the role of sirolimus in the heterogeneous spectrum of vascular anomalies is yet to be defined, in terms of indication, dosage, and therapy duration, recognizing both its potential and limitations. Methods: We retrospectively analyzed 16 children with vascular anomalies treated with sirolimus in two pediatric centers between 2014 and 2020 [male: n = 7, the median age at diagnosis: 4.6 months (range, 0-281.4)]. In addition, repetitive volumetric analyses of the vascular anomalies were performed when possible (11 cases). Results: Ten patients were diagnosed with vascular malformations and 6 with vascular tumors. The mean therapy duration was 27.2 months (range, 3.5-65). The mean sirolimus level was 8.52 ng/ml (range, 5.38-12.88). All patients except one with central conducting lymphatic anomaly responded to sirolimus, with the most noticeable volume reduction in the first 4-6 months. Additional administration of vincristine was needed in five patients with kaposiform hemangioendothelioma and yielded a response, even in cases, refractory to sirolimus monotherapy. As a single agent, sirolimus led to impressive improvement in a patient with another vascular tumor-advanced epithelioid hemangioendothelioma. Complicated vascular malformations required long-term sirolimus therapy. Side effects of sirolimus included mucositis and laboratory abnormalities. No major infectious episodes were recorded. An infant with COVID-19, diagnosed while on sirolimus therapy, presented with a mild course. Conclusion: In the current series, we reported limitations of sirolimus as monotherapy, addressing the need to redefine its indications, and explore combination regimens and multimodal treatment strategies. Tools for objective evaluation of response trends over time could serve as a basis for the establishment of future therapeutic algorithms.

Splint Duration and Not the Mode of Anesthesia Is the Main Factor Influencing Avascular Necrosis After Closed Reduction for Developmental Dysplasia of the Hip in Kosovo.

The aim of this study was to determine whether the use of analgesia and sedation (AS) as opposed to general anesthesia (GA) for closed reduction and spica casting of children with severe developmental dysplasia of the hip (DDH) influenced the long-term incidence of avascular necrosis (AVN). In a prospective, randomized, single-blinded clinical trial we investigated 100 pediatric patients with DDH type IIIa, IIIb, and IV (according to Graf classification), who were randomly assigned into the group receiving AS, and the group receiving GA. Baseline demographics, splint duration, and type of DDH were carefully assessed. The presence of AVN was assessed at the follow-up visits at 1 and 7 years after the end of treatment. The AS-group consisted of 50 patients (46 girls) with 76 hips affected (n = 11/Type-IIIa, n = 32/Type-IIIb, and n = 33/Type-IV). The GA-group consisted also of 50 patients (44 girls) with 78 hips involved (n = 15/Type-IIIa, n = 34/Type-IIIb, and n = 29/Type-IV). At 7-years follow-up, AVN was diagnosed in 9 of 154 hips (5.8%), 5 hips in the AS-group and 4 hips in the GA group. The logistic regression model showed no significant difference in AVN incidence between the AS and GA groups at 7-years follow-up (p = 0.27). The multivariate regression analysis showed that neither the type of DDH nor the age at diagnosis influenced the incidence of AVN (p = 0.48 and p = 0.28, respectively). Splint duration was identified as the only significant factor for the long-term incidence of AVN in the treatment of severe DDH. For every month of longer splint duration, the odds of AVN at 7-years follow-up increased by a factor of 3.81 (95%CI: 1.35-13.73, p = 0.02). Closed reduction and spica casting of children with severe DDH under AS can be considered a feasible alternative to management under GA. All efforts must be made to diagnose patients with DDH as early as possible and shorten the duration of splint treatment to prevent the development of AVN. Level of Evidence. Level II-1.

Congenital Hypertrophic Pyloric Stenosis in a Preterm Dizygotic Female Twin Infant: Case Report.

Infants with hypertrophic pyloric stenosis are usually diagnosed at about 3 to 8 weeks of age. The clinical onset of symptoms in preterm babies is observed normally at a later age than in term or post-term newborns. This report describes a rare case of a 2-day old preterm twin girl presenting with drinking laziness and recurrent vomiting. Five days after the beginning of symptoms and after several studies, including an upper gastrointestinal contrast study, the diagnosis of hypertrophic pyloric stenosis was made and confirmed at surgery. The postoperative course was uneventful. Interestingly, the mother of the child herself had a history of postnatal surgery on her fifth day of life due to congenital hypertrophic pyloric stenosis. To our best knowledge, this is the first report in the literature describing congenital hypertrophic pyloric stenosis in a mother and her child.

The VASCERN-VASCA working group diagnostic and management pathways for severe and/or rare infantile hemangiomas.

The European Reference Network on Rare Multisystemic Vascular Diseases (VASCERN), is dedicated to gathering the best expertise in Europe and provide accessible cross-border healthcare to patients with rare vascular diseases. Infantile Hemangiomas (IH) are benign vascular tumors of infancy that rapidly growth in the first weeks of life, followed by stabilization and spontaneous regression. In rare cases the extent, the localization or the number of lesions may cause severe complications that need specific and careful management. Severe IH may be life-threatening due to airway obstruction, liver or cardiac failure or may harbor a risk of functional impairment, severe pain, and/or significant and permanent disfigurement. Rare IHs include syndromic variants associated with extracutaneous abnormalities (PHACE and LUMBAR syndromes), and large segmental hemangiomas. There are publications that focus on evidence-based medicine on propranolol treatment for IH and consensus statements on the management of rare infantile hemangiomas mostly focused on PHACES syndrome. The Vascular Anomalies Working Group (VASCA-WG) decided to develop a diagnostic and management pathway for severe and rare IHs with a Nominal Group Technique (NGT), a well-established, structured, multistep, facilitated group meeting technique used to generate consensus statements. The pathway was drawn following two face-to-face meetings and in multiple web meetings to facilitate discussion, and by mail to avoid the influence of most authoritative members. The VASCA-WG has produced this opinion statement reflecting strategies developed by experts and patient representatives on how to approach patients with severe and rare IH in a practical manner; we present an algorithmic view of the results of our work.

Chylous content might determine the optimal surgical approach for mesenteric lymphatic malformations in childhood.

BACKGROUND: Mesenteric lymphatic malformations (LMs) represent rare congenital anomalies that can include chylous or nonchylous content. The pathologic mechanisms explaining this phenomenon are poorly understood and not yet described. Furthermore, the current management approach does not consider the contents of the mesenteric LMs. In the present study, we have defined the relationship between the lymphatic mesenteric cyst content and the histologic evidence of LMs within the bowel wall. METHODS: We retrospectively investigated all patients with mesenteric LMs treated surgically at our department from 1999 to 2018. RESULTS: A total of 11 patients (6 girls and 5 boys) were included in our analysis. Seven patients had presented with LMs located in the jejunal mesentery, three in the ileocecal region, and only one in the mesocolon transversum and omentum. Of the 11 children, 7 had had LMs with nonchylous content and 4 had presented with chylous content LMs. Intestinal resection was performed in all 4 patients with chylous content LMs and 4 patients with nonchylous content LMs. Histopathologic evaluation of the surgical specimens determined that only the LMs with chylous content displayed malformed lymphatic channels throughout the bowel wall. The resected small bowel of four patients with nonchylous content showed no LM extension throughout the intestinal wall. CONCLUSIONS: LMs with chylous content seem to develop from malformed lymphatic channels within the bowel wall. In such cases, segmental intestinal resection is mandatory. In contrast, mesenteric LMs with nonchylous content can potentially be treated without bowel resection if the blood supply can be preserved. This finding is, to the best of our knowledge, reported in the present study for the first time.

Nasal glial heterotopia: A rare interdisciplinary surgical challenge in newborns.

Nasal Glioma (NG) represents a rare congenital abnormality of the neonate, which can be associated with skull defects or even a direct communication to the central nervous system. MRI serves valuable information for differentiation from encephalocele, dermoid cyst and congenital hemangioma. Complete resection remains the treatment of choice. We present two cases of NG, which were both suspected during prenatal ultrasound and MRI. In the first case, postnatal MRI showed a transcranial continuity. Mass excision was performed and the defect was covered by a glabellar flap allowing a good cosmetic result. Postnatal MRI excluded a trans-glabellar communication in the second case. After surgical excision, the resulting skin defect was covered with a full thickness skin graft harvested from the right groin. In cases of NGs complete resection and cosmetic appealing results can be achieved and might necessitate a multidisciplinary approach.

Introducing multi-modal enteral medication reduced morbidity and mortality associated with necrotising enterocolitis.

AIM: Necrotising enterocolitis (NEC) is still a disease with high morbidity and mortality. The aim of the study was to analyse retrospectively whether the introduction of a multi-modal three-component enteral medication regimen resulted in a change in morbidity and mortality in neonates with NEC. METHODS: When diagnosis of NEC was established, the following multi-modal three-component enteral medication regimen was administered enterally (via nasogastric tube): an antibiotic, an antifungal agent and a probiotic. The primary outcome parameters were intestinal perforation, surgical interventions and mortality during the observational periods. RESULTS: In the study period, 2212 patients were admitted to the NICU, out of which 200 (9%) developed NEC. Significantly fewer infants died in the Intervention Group (13 of 104 infants, 13%) compared to the Control Group (38 of 96 infants, 40%) (P = .0001). No infant in the Intervention Group (0%) presented with an intestinal perforation, as compared to 15 infants (16%) within the Control Group (P = .0001). In the Control Group, 21 infants (22%) needed surgical intervention, whereas 0 (0%) infants needed this in the Intervention Group. CONCLUSION: The introduction of an enteral multi-modal three-component medication regimen resulted in a significant reduction of mortality and of need for surgical intervention in infants suffering from NEC.

Giant lymphatic malformation causing abdominal compartment syndrome in a neonate: a rare surgical emergency.

Abdominal lymphatic malformations in neonates require sophisticated management. In symptomatic cases, acute complications may necessitate immediate surgery. We present the case of a giant abdominal lymphatic malformation diagnosed in the 18th gestational week. Sonographic concerns about intestinal hypoperfusion in the 33rd week of gestation indicated caesarean section. Postnatal imaging confirmed a macrocystic lymphatic malformation occupying almost the complete abdominal cavity; the intestinal perfusion was normal. Clinical deterioration on Day 13 of life required laparotomy. Intraoperatively, the lymphatic mass was located in the ileocecal mesentery. Two major cysts showed recent hemorrhage explaining the onset of abdominal compartment syndrome. The malformation was completely removed. An ileocecal resection with an ileocolic anastomosis was performed. The postoperative course was uneventful. In neonates with abdominal lymphatic malformations, an onset of abdominal compartment syndrome requires surgical exploration. If feasible, the complete removal of the lesion represents a curative option.

Laparoscopic Extirpation of Adrenal Gland Ganglioneuroma Incidentally Diagnosed during Evaluation for Patchy Alopecia Areata in an Adolescent Boy.

OBJECTIVE: We present a 17-year-old boy with an incidentally diagnosed left adrenal ganglioneuroma during the diagnostic workup of alopecia areata. CLINICAL PRESENTATION AND INTERVENTION: Laboratory investigations revealed vitamin D deficiency. Laparoscopic adrenalectomy was performed and ganglioneuroma was confirmed histologically. At follow-up, the vitamin D supplements improved the vitamin D levels followed by a gradual regression of alopecia areata. However, it recurred 18 months later despite the normal levels of serum vitamin D and no tumor recurrence. CONCLUSION: Further studies should reveal the relationship between alopecia areata and ganglioneuroma as well as the role of vitamin D in alopecia areata.

[Subacute Acetabular Osteomyelitis Caused by Proteus Mirabilis. A Case Study].

Subacute acetabular osteomyelitis is a rare disease of bone. Deep location of the infection site sometimes may delay diagnosis. The most common cause is Staphylococcus aureus, whereas Proteus organisms are very rare etiologic agents. The aim of this case report is to present an unusual case of subacute acetabular osteomyelitis caused by Proteus mirabilis in a 12-year-old boy. Subacute acetabular osteomyelitis can be induced by Proteus mirabilis in the absence of previous trauma, predisposing conditions or disease. The patient was successfully treated with antibiotics. Local biopsy was essential in diagnosing this infection. Antibiotics should be given only after clinical sampling and susceptibility tests.

Complications in tissue expansion: A logistic regression analysis for risk factors.

BACKGROUND: Tissue expansion is frequently used in reconstructive surgery. Although the surgical procedure is typically considered simple, reported complication rates of tissue expansions exceed 40%. There is little evidence concerning risk factors for complications in tissue expansion in body regions other than breast. The aim was to determine risk factors for complications in non-breast tissue expansion. METHODS: 34 patients treated with subcutaneous tissue expanders between 2005 and 2014 were analyzed. Demographic data, body-mass index (BMI), mean arterial blood pressure (MAP), treatment indications, expansion site, previous expansion therapies in the same body region, smoking history, as well as expander characteristics (shape, volume, and filling mechanism) were ascertained. Complications were assessed and ranked according to severity based on the Clavien-Dindo classification. Binary logistic regression analysis adjusted for clinical characteristics was used. A p<0.05 was considered as statistically significant. RESULTS: Complications were observed in 26 out of 71 expanders analyzed (36.6%), of whom 10 led to therapy failure. Expanders used in the limbs, female gender, and high expander volume turned out as significant risk factors. Patients with both a high MAP and low BMI developed tissue necrosis significantly more often (p=0.002). The use of tissue expansion after a burn was not associated with an increased risk for complications. CONCLUSIONS: This is the first study revealing female gender and low BMI as risk factors in tissue expander surgery. Thus, careful patient selection is mandatory to avoid complications in tissue expansion. Burn patients do not develop complications more often.