Plexiform neurofibroma masquerading as a giant congenital melanocytic nevus.

A 4-month-old male presented for a large, hypertrichotic brown patch on the upper back with several scattered 0.5-1.5 cm, round to oval, brown macules and patches on the trunk and extremities. The lesion was initially diagnosed as a giant congenital melanocytic nevus based on clinical exam and histopathology with immunohistochemical stains. The patient was later diagnosed with neurofibromatosis type 1, and the lesion on the back developed a "bag of worms" texture consistent with a plexiform neurofibroma and found to harbor a pathogenic variant in the NF1 gene. This case highlights the diagnostic challenge of differentiating these lesions and their overlapping clinical and histopathological features.

Limited utility of repeated vital sign monitoring during initiation of oral propranolol for complicated infantile hemangioma.

BACKGROUND: Initial propranolol recommendations for infantile hemangioma published in 2013 were intended as provisional best practices to be updated as evidence-based data emerged. METHODS: A retrospective multicenter study was performed to evaluate utility of prolonged monitoring after first propranolol dose and escalation(s). Inclusion criteria included diagnosis of hemangioma requiring propranolol of greater than or equal to 0.3 mg/kg per dose, younger than 2 years, and heart rate monitoring for greater than or equal to 1 hour. Data collected included demographics, dose, vital signs, and adverse events. RESULTS: A total of 783 subjects met inclusion criteria; median age at initiation was 112 days. None of the 1148 episodes of prolonged monitoring warranted immediate intervention or drug discontinuation. No symptomatic bradycardia or hypotension occurred during monitoring. Mean heart rate change from baseline to 1 hour was -8.19/min (±15.54/min) and baseline to 2 hours was -9.24/min (±15.84/min). Three preterm subjects had dose adjustments because of prescriber concerns about asymptomatic vital sign changes. No significant difference existed in pretreatment heart rate or in heart rate change between individuals with later adverse events during treatment and those without. CONCLUSION: Prolonged monitoring for initiation and escalation of oral propranolol rarely changed management and did not predict future adverse events. Few serious adverse events occurred during therapy; none were cardiovascular.

Infantile and congenital hemangiomas.

Infantile hemangiomas (IHs) are the most common benign tumors of infancy. They typically appear after birth and undergo a period of rapid growth, followed by a gradual period of involution. Although the majority of IHs do not requirement treatment, oral propranolol is the first-line therapy for lesions that are at risk for life-threatening complications, functional impairment, ulceration, or permanent disfigurement. Rarely, IHs can be associated with structural anomalies. Congenital hemangiomas (CHs) are a distinct clinical entity, caused by a point mutation in GNAQ or GNA11. These lesions are typically present at birth and display a wide spectrum of clinical presentations. CHs can be distinguished from IHs by their unique histologic and radiographic features. Given the high-flow vascularity of CHs, surgical excision may be indicated due to the high risk of bleeding.

Evaluating the Safety of Oral Propranolol Therapy in Patients With PHACE Syndrome.

Importance: Oral propranolol is widely considered to be first-line therapy for complicated infantile hemangioma, but its use in patients with PHACE (posterior fossa malformations, hemangioma, arterial anomalies, cardiac defects, eye anomalies) syndrome has been debated owing to concerns that the cardiovascular effects of the drug may increase the risk for arterial ischemic stroke. Objective: To assess the incidence of adverse events among patients with PHACE syndrome receiving oral propranolol for infantile hemangioma. Design, Setting, and Participants: This multicenter retrospective cohort study assessed the incidence of adverse events among 76 patients with PHACE syndrome receiving oral propranolol for infantile hemangioma at 11 tertiary care, academic pediatric dermatology practices. Medical records from January 1, 2010, through April 25, 2017, were reviewed. Exposures: Patients received oral propranolol, 0.3 mg/kg/dose or more. Main Outcomes and Measures: The main outcome was the rate and severity of adverse events occurring throughout the course of treatment with oral propranolol, as documented in the medical records. Adverse events were graded from 1 to 5 using a scale derived from the Common Terminology Criteria for Adverse Events and were considered to be serious if they were grade 3 or higher. Results: A total of 76 patients (59 girls and 17 boys; median age at propranolol initiation, 56 days [range, 0-396 days]) met the inclusion criteria. There were no reports of serious adverse events (ie, stroke, transient ischemic attack, or cardiovascular events) during treatment with oral propranolol. A total of 46 nonserious adverse events were reported among 29 patients (38.2%); the most commonly reported nonserious adverse events were sleep disturbances and minor gastrointestinal tract and respiratory tract symptoms. In a comparison with 726 infants who received oral propranolol for hemangioma but did not meet criteria for PHACE syndrome, there was no significant difference in the rate of serious adverse events experienced during treatment (0 of 76 patients with PHACE syndrome and 3 of 726 patients without PHACE syndrome [0.4%]). Conclusions and Relevance: This study found that oral propranolol was used to treat infantile hemangioma in 76 patients with PHACE syndrome and that no serious adverse events were experienced. These data provide support for the safety of oral propranolol in this patient population.

Divergent MLS1 Promoters Lie on a Fitness Plateau for Gene Expression.

Qualitative patterns of gene activation and repression are often conserved despite an abundance of quantitative variation in expression levels within and between species. A major challenge to interpreting patterns of expression divergence is knowing which changes in gene expression affect fitness. To characterize the fitness effects of gene expression divergence, we placed orthologous promoters from eight yeast species upstream of malate synthase (MLS1) in Saccharomyces cerevisiae As expected, we found these promoters varied in their expression level under activated and repressed conditions as well as in their dynamic response following loss of glucose repression. Despite these differences, only a single promoter driving near basal levels of expression caused a detectable loss of fitness. We conclude that the MLS1 promoter lies on a fitness plateau whereby even large changes in gene expression can be tolerated without a substantial loss of fitness.