SKIN January 2023 Volume 7 Issue 1 (c) 2022 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 642 SKINmages Focal Hypertrichosis in an Infant as the Presenting Sign of Nevoid Basal Cell Carcinoma Syndrome Natalie V. Garcia, BS1, Victoria Jiminez, BS1, Abigail M. Smith, MD1, and Amy Theos, MD1,2 1University of Alabama at Birmingham Heersink School of Medicine, Birmingham, AL 2Children’s of Alabama, Birmingham, AL Nevoid basal cell carcinoma syndrome (NBCCS), or Gorlin Syndrome, is a neurocutaneous disorder caused by mutations in the PTCH1 or, less commonly, SUFU genes. Mutations in these genes lead to malfunction of the sonic hedgehog pathway, causing unregulated cell proliferation and differentiation. The sonic hedgehog signaling pathway plays a crucial role in the development of many systems including the axial skeleton, limbs, gut endoderm, and the hair follicle. As a result of this unregulated cell proliferation, NBCCS classically presents with dermatologic manifestations including basal cell carcinomas (BCC), palmar and plantar pits, and milia. Other common manifestations INTRODUCTION SKIN January 2023 Volume 7 Issue 1 (c) 2022 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 643 include odontogenic jaw cysts, calcification of the falx cerebri, and skeletal abnormalities.1,2 As the sonic hedgehog pathway affects hair follicle growth and development, PTCH1 mutations could lead to unregulated hair follicle proliferation. A case series by Notay et al. highlights the presence of patches of hair as an early sign of NBCCS.3 We present the case of a patient whose discrete tufts of hair led to the diagnosis of NBCCS. A nine-month-old female presented for evaluation of multiple tufts of hair which had been present since four months of age. She had no other significant medical history and was born full-term without complications. At her initial visit she did not have macrocephaly. Physical exam was notable for multiple focal patches of dark terminal hairs with normal underlying skin involving the right forearm, left wrist, lateral forehead, and left side of the mons pubis. She was diagnosed with localized hypertrichosis and no further workup was pursued. Two years later, the patient presented with macrocephaly and developmental delay. Dermatologic exam at this time revealed two new patches of hair growth in addition to the patches noted previously on exam. Subsequent genetic testing found a heterozygous pathogenic mutation in the PTCH1 gene, c.202-1 G>A, confirming the diagnosis. Over the next ten years, she was followed by an outside dermatologist where she was treated for hundreds of basal cell carcinomas with multiple modalities including imiquimod cream, electrodessication and curettage, and CO2 laser under general anesthesia. She returned to our clinic ten years after her initial diagnosis, and her isolated patches of hypertrichosis remained unchanged (Figure 1,2). Hypertrichosis can be either congenital or acquired, and within these categories you have both localized and generalized forms. Localized hypertrichosis carries a small differential diagnosis such as nevoid hypertrichosis, Becker’s nevi, or other localized symmetric hypertrichosis including the faun-tail deformity.5 This case demonstrates that NBCCS should be considered within the differential diagnosis of localized hypertrichosis, as this patient is the sixth case to demonstrate this finding as an early sign of NBCCS.3,4 Further, it may be useful to include scattered hairy patches of skin as one of the cutaneous findings in NBCCS along with palmar/plantar pits, basal cell carcinomas, and milia, as early intervention is crucial to preventative care including avoidance of irradiation, sun protective precautions, and for appropriate screening for other sequelae of NBCCS. Conflict of Interest Disclosures: None Funding: None Corresponding Author: Amy Theos, MD UAB Department of Dermatology Phone: (205) 638-4823 Email: dermatology@childrensal.org References: 1. Thalakoti S, Geller T. Basal cell nevus syndrome or Gorlin syndrome. Handb Clin Neurol. 2015;132:119-128. doi:10.1016/B978-0-444- 62702-5.00008-1 2. Gorlin RJ. Nevoid basal cell carcinoma (Gorlin) syndrome. Genet Med. 2004;6(6):530-539. doi:10.1097/01.gim.0000144188.15902.c4 3. Notay M, Kamangar F, Awasthi S, Fazel N. Nevoid Basal Cell Carcinoma Syndrome and CASE REPORT DISCUSSION mailto:dermatology@childrensal.org mailto:dermatology@childrensal.org SKIN January 2023 Volume 7 Issue 1 (c) 2022 THE AUTHORS. Published by the National Society for Cutaneous Medicine. 644 Hairy Skin Patches. Pediatr Dermatol. 2017;34(2):e97-e98. doi:10.1111/pde.13067 4. Wilson LC, Ajayi-Obe E, Bernhard B, Maas SM. Patched mutations and hairy skin patches: a new sign in Gorlin syndrome. Am J Med Genet A. 2006 Dec 1;140(23):2625-30. doi: 10.1002/ajmg.a.31374. PMID: 16906569. 5. Vashi RA, Mancini AJ, Paller AS. Primary generalized and localized hypertrichosis in children. Arch Dermatol. 2001;137(7):877-884.