Giant Congenital Melanocytic Nevus with Multiple Satellite Lesions and Normal Neuroimaging in an Infant: A Case Report

Abstract

Aims: To describe the clinical presentation and initial neuroimaging findings of an infant with giant congenital melanocytic nevus (GCMN) and multiple satellite lesions, and to emphasise the need for risk-based multidisciplinary follow-up despite normal baseline magnetic resonance imaging (MRI). Presentation of Case: A 9-month-old female infant was evaluated for congenital pigmented skin lesions. Examination showed an extensive dark brown to black, smooth-surfaced hyperpigmented plaque with dense hypertrichosis in a bathing-trunk distribution, involving the lower thoracoabdominal and lumbar regions and measuring approximately 20 × 14 cm. Multiple round-to-oval satellite melanocytic nevi measuring 0.5–1.5 cm in diameter were present on both lower limbs. Psychomotor development was appropriate for age, and neurological and ophthalmological examinations were normal. Brain and spinal MRI showed no leptomeningeal melanosis, intracranial melanocytic deposits, hydrocephalus or spinal involvement. Discussion: The lesion’s posterior axial distribution, large projected adult size, dense hypertrichosis and multiple satellite nevi define a clinically high-risk phenotype. The normal initial MRI is reassuring but represents neurological status at the time of imaging and does not remove the need for continued clinical surveillance. Conclusion: Long-term dermatological and neurological follow-up is appropriate, with management individualised according to lesion characteristics, clinical evolution and family preferences within a multidisciplinary setting.