The International Society for the Study of Vascular Anomalies classifies vascular anomalies into vascular tumors and vascular malformations. Vascular tumors are neoplasms of endothelial cells, among which infantile hemangiomas (IHs) are the most common, occurring in 5%–10% of infants. Glucose transporter-1 protein expression in IHs differs from that of other vascular tumors or vascular malformations. IHs are not present at birth but are usually diagnosed at 1 week to 1 month of age, rapidly proliferate between 1 and 3 months of age, mostly complete proliferation by 5 months of age, and then slowly involute to the adipose or fibrous tissue. Approximately 10% of IH cases require early treatment. The 2019 American Academy of Pediatrics clinical practice guideline for the management of IHs recommends that primary care clinicians frequently monitor infants with IHs, educate the parents about the clinical course, and refer infants with high-risk IH to IH specialists ideally at 1 month of age. High-risk IHs include those with life-threatening complications, functional impairment, ulceration, associated structural anomalies, or disfigurement. In Korea, IHs are usually treated by pediatric hematology-oncologists with the cooperation of pediatric cardiologists, radiologists, dermatologists, and plastic surgeons. Oral propranolol, a nonselective beta-adrenergic antagonist, is the first-line treatment for IHs at a dosage of 2–3 mg/kg/day divided into 2 daily doses maintained for at least 6 months and often continuing until 12 months of age. Topical timolol maleate solution, a topical nonselective beta-blocker, may be used for small superficial type IHs at a dosage of 1–2 drops of 0.5% gel-forming ophthalmic solution applied twice daily. Pulse-dye laser therapy or surgery is useful for the treatment of residual skin changes after IH involution.
Current diagnostic tests for hereditary spherocytosis (HS) focus on the detection of hemolysis or indirectly assessing defects of membrane protein, whereas direct methods to detect protein defects are complicated and difficult to implement. In the present study, we investigated the patterns of genetic variation associated with HS among patients clinically diagnosed with HS. Multi-gene targeted sequencing of 43 genes (17 RBC membrane protein-encoding genes, 20 RBC enzyme-encoding genes, and six additional genes for the differential diagnosis) was performed using the Illumina HiSeq platform. Among 59 patients with HS, 50 (84.7%) had one or more significant variants in a RBC membrane protein-encoding genes. A total of 54 significant variants including 46 novel mutations were detected in six RBC membrane protein-encoding genes, with the highest number of variants found in SPTB (n = 28), and followed by ANK1 (n = 19), SLC4A1 (n = 3), SPTA1 (n = 2), EPB41 (n = 1), and EPB42 (n = 1). Concurrent mutations of genes encoding RBC enzymes (ALDOB, GAPDH, and GSR) were detected in three patients. UGT1A1 mutations were present in 24 patients (40.7%). Positive rate of osmotic fragility test was 86.8% among patients harboring HS-related gene mutations. This constitutes the first large-scaled genetic study of Korean patients with HS. We demonstrated that multi-gene target sequencing is sensitive and feasible that can be used as a powerful tool for diagnosing HS. Considering the discrepancies of clinical and molecular diagnoses of HS, our findings suggest that molecular genetic analysis is required for accurate diagnosis of HS.
1 January 2020 in Journal of Korean Medical Science