Clinical Management and Genetic Analysis of a Complex Case of Segmental Infantile Hemangioma with Subcutaneous Pelvic and Gluteal Tumefactions.

introductionInfantile hemangiomas (IHs) are the most prevalent noncancerous childhood tumors, affecting up to 10% of infants. IHs develop de novo and following excessive proliferation in the first 4-9 months; they typically degenerate spontaneously in 4-7 years. While treatment is not usually required, 10-15% of cases necessitate clinical or surgical intervention due to functional impairments. Here, we present a complicated capillary IH case, from a clinical and genetic perspective. MATERIAL AND

methodsA 13-month-old patient, with free family history, presented with a cutaneous capillary-venous malformation of the thigh as well as pelvic and gluteal subcutaneous masses, resulting in urinary-bladder displacement, kidney distention, cortical thinning, pyelocaliceal dilation, and rectosigmoid displacement. Following the alleviation of the patient's symptoms and the conduction of a percutaneous nephrostomy, Sirolimus was administered for 2 years at the recommended dose. Moreover, after clinical genetic examination and informed consent of the parents, genomic DNA was extracted from a patient's peripheral blood sample and an analysis of whole-exon sequencing (WES) was performed.

resultsTreatment was successful in diminishing the pelvic and gluteal masses, but the cutaneous malformation remained. WES revealed the heterozygous c.1416A>T:p.Q472H mutation in exon 11 of the KDR gene, that encodes kinase insert domain receptor.

conclusionAccording to the clinical presentation and the results of the genetic analysis, the patient was diagnosed with segmental capillary IH, caused by a missense pathogenic variant in the KDR gene, which impairs protein function and might also be responsible for the presented subcutaneous malformations.