Scoliosis with axillary freckling is a clue for which systemic condition?

• A. Neurofibromatosis type 1
• B. Osteoporosis
• C. Marfan syndrome
• D. Ehlers-Danlos syndrome

Answer: (A)

Scoliosis with axillary freckling points to neurofibromatosis type 1. Axillary freckling, known as Crowe sign, is a classic skin finding in NF1 caused by mutations in the NF1 gene. NF1 is an autosomal dominant disorder with variable expression, and skeletal manifestations such as scoliosis are common due to underlying bone dysplasia. The combination of skin markings (café-au-lait spots and axillary freckling) with scoliosis strongly suggests NF1. The other conditions don’t typically feature axillary freckling: osteoporosis centers on bone density loss; Marfan syndrome has tall stature, long limbs, and cardiovascular features like aortic root dilation; Ehlers-Danlos presents with joint hypermobility and skin fragility.