Nevus comedonicus is an uncommon
skin abnormality characterized by an aggregation of dilated follicular orifices filled with keratinous material.
Nevus comedonicus is occasionally complicated with other conditions including
cataracts, skeletal defects, central nervous system abnormalities or other extra-cutaneous diseases (
nevus comedonicus syndrome). Although most cases of
nevus comedonicus occur unilaterally on the face, neck and chest, the lesions occasionally show a bilateral distribution (bilateral
nevus comedonicus). We report here an unusual case of bilaterally disseminated
nevus comedonicus with various systemic complications. A 62-year-old Japanese man presented with a 50-year history of numerous keratotic papules and comedo-like lesions, which gradually worsened with time. Physical examination revealed that the papules were skin-colored and 1-4 mm in diameter. Some papules had dark-black keratinous materials on their surface, giving them a comedo-like appearance. The lesions were located predominantly on the face, head, neck and trunk with symmetric distribution, following Blaschko's lines. The patient's past medical history was noteworthy; he had undergone surgical treatments for
thyroid cancer,
pneumothorax and
schwannoma in the cauda equina. He also suffered from
scoliosis,
cervical spondylosis and
atrial fibrillation. Histopathologic examination revealed dilated and invaginated follicular structures filled with lamellar
keratin, compatible with
nevus comedonicus. Our patient's case did not fit with any previously reported diseases, and we thought a diagnosis of "bilateral
nevus comedonicus syndrome" was the most appropriate for our patient's condition. He was treated with topical
retinoic acid and activated
vitamin D3 ointment for 3 months each, but the lesions remained unchanged.