To the Editor:
A 12-year-old girl presented with discomfort and walking limitation caused by cutaneous masses on the plantar aspects of the feet with associated bone abnormalities that had started as several flesh-colored papules on the plantar surface of both feet at the age of 1 year. Over time the lesions gradually enlarged and formed irregular masses, more prominently on the right foot. At the age of 6 years, surgical correction was performed due to increased walking impairment and a skin examination that suggested connective tissue nevus. The results were good. However, the local tissue overgrowth recurred after 1 year. Slowly growing lesions were found at the surgical site, which necessitated hospitalization. Her medical history was negative for other disease. There was no family history of similar skin conditions and her parents were nonconsanguineous.
Physical examination revealed malnutrition and poor development in height as well as difficulty walking. She also had moderate scoliosis with a curve to the left. Dermatological examination showed multiple reddish cerebriform hyperplasia in both plantar areas; the right side was more severely involved (Figure 1A). There was macrodactyly of 2 toes on the right foot (Figure 1B). All results of routine blood examinations were within reference range. There were no abnormalities noted in the abdominal ultrasound and cardiac examinations. Plain radiographs of the spine and feet demonstrated scoliosis and exostosis on the calcaneus and bottom of the scaphoid. Histopathologic examination of tissue from the plantar cerebriform hyperplasia revealed hyperkeratosis, slight acanthosis and papillomatosis in the epidermis, and dense collagen bands and sparse elastic fibers in the dermis (Figure 2).
Figure 1. Multiple reddish plantar cerebriform hyperplasia before the second surgery (A) and macrodactyly of 2 toes on the right foot (B).
Figure 2. Hyperkeratosis, slight acanthosis and papillomatosis in the epidermis, and dense collagen bands in the dermis (H&E, original magnification ×200).
Given the clinical and radiologic manifestation, the diagnosis of Proteus syndrome (PS) was established. After taking into account the severe discomfort and the success of the first surgery, we performed a resection and full-thickness skin graft surgery once again. The feet recovered without any discomfort in daily life. The appearance of the skin graft area was normal 1 year following surgery (Figure 3). She was treated with spinal plate fixation at another institution, progressed well for 2 years, and was subsequently lost to follow-up.
Figure 3. The skin graft area was healed 1 year following surgery.
Proteus syndrome is a multisystem disorder with a difficult diagnosis due to the variability of its manifestations. The worldwide incidence of this rare disorder is less than 1 per 1 million individuals, and it is thought to be caused by a somatic genetic alteration.1 Clinical characteristics include bone abnormalities, vascular malformations, dysregulation of fatty tissue, linear verrucous epidermal nevus, and cerebriform connective tissue nevus (CCTN). Although CCTN is not a common finding in patients with PS, it is considered a fairly specific sign with the greatest impact for the diagnosis of PS.2
The general feature of PS--asymmetric disproportionate overgrowth of tissues--appears at 6 to 18 months of age, which makes it challenging to diagnose disease earlier. The CCTN in our patient was present since 1 year of age.