Frieden, Ilona J.

Objectives: Systemic beta-blockers are highly effective for the management of infantile hemangiomas (IH), but little is known about infants who do not adequately respond. We aimed to describe the characteristics and outcomes of suboptimal responders to standard-dose systemic beta-blockers in infants with IH. Methods: This is a multicenter retrospective cohort study to evaluate demographics, IH lesion characteristics, and treatment specifics of infants with IH with suboptimal response to baseline standard-dose propranolol treatment. Clinical response was used to assess the outcome after a therapeutic change. Results: Twenty-five infants were included in this study. Seven (28%) had segmental IH, 16 (64%) focal, and 2 (8%) indeterminate. The IHs were located on the head and neck in 21 (84%) infants, with 24 (96%) having a deep or combined component. Therapy changes after standard-dose propranolol treatment failure, most commonly by escalating propranolol dose to ≥2.5 mg/kg/d (59%) or surgical interventions (29%), were associated with good therapeutic effects. Conclusion: Among suboptimal responders to standard-dose systemic propranolol, IHs with a deep or combined component and located on the head and neck were the most common. This retrospective study was largely descriptive in nature with additional exploratory analyses. However, it is still encouraging that for patients with a suboptimal clinical response, higher propranolol doses of ≥2.5–3 mg/kg/d or second-line treatments with surgical interventions or systemic steroids can be considered as potentially safe and effective alternatives. Level of evidence: Level 4 (case series).

The PI3K enzymes modify phospholipids to regulate cell growth and differentiation. Somatic variants in PI3K are recurrent in cancer and drive a proliferative phenotype. Somatic mosaicism of PIK3R1 and PIK3CA are associated with vascular anomalies and overgrowth syndromes. Germline PIK3R1 variants are associated with varying phenotypes, including immunodeficiency or facial dysmorphism with growth delay, lipoatrophy, and insulin resistance associated with SHORT syndrome. There has been limited study of the molecular mechanism to unify our understanding of how variants in PIK3R1 drive both undergrowth and overgrowth phenotypes. Thus, we compiled genomic variants from cancer and rare vascular anomalies and sought to interpret their effects using an unbiased physics-based simulation approach for the protein complex. We applied molecular dynamics simulations to mechanistically understand how genetic variants affect PIK3R1 and its interactions with PIK3CA. Notably, iSH2 genetic variants associated with undergrowth destabilize molecular interactions with the PIK3CA receptor binding domain in simulations, which is expected to decrease activity. On the other hand, overgrowth and cancer variants lead to loss of inhibitory interactions in simulations, which is expected to increase activity. We find that all disease variants display dysfunctions on either structural characteristics or intermolecular interaction energy. Thus, this comprehensive characterization of novel mosaic somatic variants associated with two opposing phenotypes has mechanistic importance and biomedical relevance and may aid in future therapeutic developments.

AbstractBackground/ObjectivesUlceration is a common complication of infantile hemangioma (IH). Severe, persistent ulceration occurs in a minority of patients. This study aims to characterize the clinical features of IH with aggressive ulceration (AU).MethodsMulticenter retrospective study of clinical features of IH with AU.ResultsThirty‐five patients with AU were identified and included in the study. The majority of AU occurred in segmental IH (23/35, 65%). Segmental IH with AU were large (≥10 cm2; 16/23, 69%, p < .001) with a thin (<3 mm) superficial component (16/23, 69%, p < .001). Localized IH with AU had a thick (>3 mm) superficial component (11/12, 92%, p < .001).All diaper area IH with AU (9/35) were segmental with thin superficial component (100%, p = .02). IH with AU in the head/neck (10/35) were more commonly localized (67%) and mixed (62.5%), while segmental, thick superficial morphology was more common on trunk (9/35) and upper extremities (7/35).ConclusionsIH resulting in AU differ in clinical features by anatomic site. Those in the diaper area are nearly always segmental with thin superficial component, whereas other sites tend to be localized, mixed, with thick superficial component. These distinct phenotypes may prove useful in the clinical setting for physicians to identify patterns of IH ulceration with increased risk of aggressive, persistent ulceration.

Objective(s): PIK3CA-related overgrowth spectrum (PROS) is a group of disorders caused by somatic variants in the PIK3CA gene. We aimed to update recommendations on the severity classification, testing, and medical management of patients with PROS. Methods: Using validated consensus methodology, we convened a 13-member panel in 2020 and reviewed current evidence on how to diagnose and treat PROS. The panel was asked to rate the level of disease severity, and the appropriateness of whether to test for a mutation and medical therapy in 217 patient scenarios before a virtual meeting. Panelists discussed areas of disagreement and completed ratings following the meeting. Results: The panel developed clinical presentations and endorsed the disease severity framework defined by functional impairment, a reduction in quality of life, and risk of death. Panelists agreed it is appropriate to test for a PIK3CA gene variant in every moderately/severely affected patient. Panelists agreed it may be appropriate to consider an mammalian (mechanistic) target of rapamycin inhibitor in some severely affected patients and some moderately affected patients with progressive disease. Although clinical trials have only recently begun and the evidence remains limited, panelists also agreed it may be appropriate to consider treatment with phosphoinositide 3-kinase/serine/threonine protein kinase inhibitors in severely affected patients with a confirmed PIK3CA variant or without a confirmed variant but with progressive disease. Conclusion: These recommendations represent the consensus of experts informed by published literature and experience. Future research should validate this guidance using clinical data. Once validated, we hope these recommendations will improve outcomes for patients with PROS.

Abstract Background Capillary lymphatic venous malformations (CLVM) and associated syndromes, including Klippel–Trenaunay syndrome (KTS) and congenital lipomatous overgrowth, vascular malformation, epidermal nevi, skeletal, and spinal syndrome (CLOVES), are underrecognized disorders associated with high morbidity from chronic pain, recurrent infections, bleeding, and clotting complications. The rarity of these disorders and heterogeneity of clinical presentations make large‐scale randomized clinical drug trials challenging. Identification of PIK3CA (phosphatidylinositol‐4,5‐bisphosphate 3‐kinase catalytic subunit alpha [gene]) mutations in CLVM has made targeted medications, such as sirolimus, attractive treatment options. The aim of this study was to investigate the safety and efficacy of sirolimus therapy in CLVM. Procedure A combined prospective and retrospective cohort of pediatric and young adult patients with CLVM treated with sirolimus was evaluated for disease response, including symptom improvement, quality of life (QOL), and radiologic response. Sirolimus dosing regimens and toxicities were also assessed. Results Twenty‐nine patients with CLVM, including KTS and CLOVES, were included. Ninety‐three percent of patients reported improved QOL, and 86% had improvement in at least one symptom. Most significantly, improvement was noted in 100% of patients with bleeding and 89% with thrombotic complications with corresponding decreases in mean D‐dimer ( p = .008) and increases in mean fibrinogen ( p = .016). No patients had progressive disease on sirolimus. Most common side effects included neutropenia, lymphopenia, infection, and aphthous ulcers/stomatitis. No toxicities were life‐threatening, and none required long‐term discontinuation of sirolimus. Conclusion Sirolimus appears to be effective at reducing complications and improving QOL in patients with CLVM and associated syndromes. In this patient cohort, sirolimus was well tolerated and resulted in few treatment‐related toxicities.

AbstractBackground/ObjectivesThe COVID‐19 pandemic prompted a rapid expansion in the use of telemedicine. This study aimed to assess the experiences of hemangioma specialists utilizing telemedicine during the COVID‐19 pandemic to evaluate and manage infantile hemangiomas (IH), including perceived effectiveness of different modalities and barriers to care delivery.MethodsMulticenter cross‐sectional study asking providers to describe their experiences using telemedicine for initial evaluation of IH from March to September 2020.ResultsThe study included 281 patients from 15 medical centers internationally. Median time from referral to evaluation was 17 days. Median physician confidence in performing evaluations via telemedicine was 95.0 (IQR 90.0–100.0). Most evaluations were performed via video communication with photographs or audio communication with photographs; when not initially available, photographs were requested in 51.4%. Providers preferred follow‐up modalities that included photographs.ConclusionsPhysicians with extensive expertise in managing IH are confident in their abilities to assess and manage IH via telemedicine including initiating treatment in patients without risk factors for beta‐blocker therapy. There was a preference for hybrid modalities that included photographs. The data suggest that telemedicine can be effective for managing IH and may decrease wait times and improve specialist reach to underserved areas.

AbstractBackground/ObjectivesThe COVID‐19 pandemic has raised questions about the approach to management of systemic immunosuppressive therapies for dermatologic indications in children. Change to: Given the absence of data to address concerns related to SARS‐CoV‐2 infection and systemic immunosuppressive therapies in an evidence‐based manner, a Pediatric Dermatology COVID‐19 Response Task Force (PDCRTF) was assembled to offer time‐sensitive guidance for clinicians.MethodsA survey was distributed to an expert panel of 37 pediatric dermatologists on the PDCRTF to assess expert opinion and current practice related to three primary domains of systemic therapy: initiation, continuation, and laboratory monitoring.ResultsNearly all respondents (97%) reported that the COVID‐19 pandemic had impacted their decision to initiate immunosuppressive medications. The majority of pediatric dermatologists (87%) reported that they were pausing or reducing the frequency of laboratory monitoring for certain immunosuppressive medications. In asymptomatic patients, continuing therapy was the most popular choice across all medications queried. The majority agreed that patients on immunosuppressive medications who have a household exposure to COVID‐19 or test positive for new infection should temporarily discontinue systemic and biologic medications, with the exception of systemic steroids, which may require tapering.ConclusionsThe ultimate decision regarding initiation, continuation, and laboratory monitoring of immunosuppressive therapy during the pandemic requires careful deliberation, consideration of the little evidence available, and discussion with families. Consideration of an individual's adherence to COVID‐19 preventive measures, risk of exposure, and the potential severity if infected must be weighed against the dermatological disease, medication, and risks to the patient of tapering or discontinuing therapies.