Absence of Human Papillomavirus DNA in Nongenital Seborrheic Keratosis

Seborrheic keratosis (SK) is a benign epidermal tumor of unknown etiology. Because of its wart-like morphology, human papillomavirus (HPV) has been suggested as a possible causative agent. Viral involvement, however, has not been confirmed yet despite extensive research. The aim of this study was to evaluate the presence of HPV 6/11, 31, 33 DNA in nongenital SK. We analyzed 40 biopsy specimens taken from patients with nongenital SK using in situ polymerase chain reaction (PCR) and PCR with tissue extracts. The SK specimens (n=40), analyzed by in situ PCR, were negative for all HPV probes tested (types 6/11, 31, 33). Control slides (condyloma acuminatum, n=3) were positive for type 6/11, 31, and 33 HPV probes tested. Melasma samples (n=4), the negative controls, were consistently negative. No HPV DNA band was detected by PCR with the tissue extracts from paraffin-embedded SK samples, while condyloma acuminatum, the positive controls, showed DNA bands of the correct molecular weights. Our results show that HPV type 6/11, 31, and 33 cannot be recognized as causative agents for nongenital SK, which is in contrast to the previous studies. Further studies are required to reveal the presence of other types (more than 90) of HPV DNA.

Prurigo Pigmentosa Caused by Sweating

Prurigo pigmentosa is a peculiar pruritic pigmented dermatosis characterized by the sudden appearance of reddish papules accompanied by severe pruritus. The etiology still remains unknown but environmental factors may play a role, in which physical trauma or friction from wet clothing induces the skin lesions. It has a seasonal preference for spring to summer when there is increased sweating. We report a case of prurigo pigmentosa which may be triggered by sweating and cured with minocycline.

A Case of Granuloma Faciale Treated with Co2 Laser / 대한피부과학회지

Granuloma faciale is a rare disease of unknown origin characterized by single or multiple cutaneous nodules usually occurring on the face. A narrow grenz zone of normal dermis is usually observed between the epidermis and the dense dermal polymorphous infiltrates. We report a case of granuloma faciale in a 40-year-old male patient with erythematous plaque on his nose. The skin biopsy specimen showed a dense dermal accumulation of inflammatory cells, including neutrophils, eosinophils, monocytes, and lymphocytes. The infiltrate was distributed diffusely throughout the involved dermis and it focally involved the thinned and flattened epidermis. There is deposition of fibrinoid material within and around the affected lood wessels. The lesion was treated with CO2 laser effectively.