Diagnosis of Causative Fungi of Onychomycosis Using Polymerase Chain Reaction and Restriction Enzyme Analysis / 대한의진균학회지

BACKGROUND: Onychomycosis has become one of the common fungal infection. However, highly reliable and sensitive methods of detecting and identifying causative fungi of onychomycosis are not established yet. Polymerase chain reaction (PCR) analysis of clinical specimens including blood, sputum, urine, and cerebrospinal fluid collected from patient systemically infected fungus is known as a sensitive diagnostic method. But it has been questionable whether PCR analysis is also applicable to onychomycosis. OBJECTIVE: The purpose of this study was to develop a DNA-based diagnostic method to improve the sensitivity and specificity of detection and identification of pathogenic fungi of onychomycosis. METHODS: To detect the fungi in the nail, PCR was performed by using 4 sets of primer (TR1 & TR2, NS5 & NS6, B2F & B4R and CA1 & CA2) designed in conserved sequences of the small ribosomal subunit (185-rRNA) genes and restriction enzyme analysis of amplified product by Hae III was done to identify species. Nail specimens were obtained from 19 cases of onychomycosis confirm by fungus culture. RESULTS: 1. Preparation of nail powder, which is necessary for removal of keratin, and composition of lysis buffer with guanidinium thiocyanate, Tris-HCl, and beta -mercaptoethanol are the most proper modalities for isolation of fungal DNA from fungus-infesting nails. 2. Specific fragments of the 18S-rRNA gene of fungi, 581 bp, 308 bp, 688 bp and 1106 bp were amplified respectively. From sequences of 18S-rRNA gene of fungi by universal primers, dermatophytes (Trichophyton rubrum, Trichophyton mentagrophytes) and yeast (Candida albicans) yielded identical products. 3. Using Hae III endonuclease, digested patterns of fragment of Trichophyton rubrum and Candida albicans resulted in different pattern. CONCLUSION: This method released enough DNA from fungus-infected nails to result in proper amplification and it can be possible to differentiate dermatophytes, yeasts, and molds using Hae III endonuclease. The present study is the first one to demonstrate the feasibility of this molecular biologic approach to identify fungi in the infected nail. Therefore, precise detection and identification of the causative fungi would be of help in investigating distribution of the causative fungi of onychomycosis as well as appropriate treatment of the disease.

Case of rat mite dermatitis / 대한피부과학회지

We report three cases of rat mite dermatitis caused by Ornithonysus bacoti(Hirst, 1913), commonly referred to it as the tropicalrat mite. The first case, a 26-year old female had multiple pinhead sized vesicles with peripheral erythematous macule on the upper arms. The second case, a 34-year-old femal had multiple variable sized vesicles with erythematous base on the extremeties. The third case, a 43-year old male had multiple erythematous macules and papules with central punctum on the trunl: and extremities. Histopathologic sections from lesions of the first and second patient showed moderate perivascular lymphahistiocytic infiltration intermingled with some eosinophils. Causative mites, Ornithonyssus bacoti, female were collected around the skin lesion in rase 1, from the house dust in case 2 and furniture in case 3.

Cryotherapy in a patient with acquired tufted angioma / 대한피부과학회지

A 26-year old woman had tender erythematous grouped papules and plaque(10 cm in diameter) with underlying deep seated rodules on the right shoulder for 2 years. A biopsy specimen showed vascular tufts composed of endothelial cells in the mid and lower dermis, which was diagnostic of acquired tufted angioma. After 4-months of cryotherapy with liquid nitrogen, most of the lesions had disappeared as well as her subjective symptom.

A Case of Plexiform Neurofibroma Developed under the Overlying Speckled Lentiginous Nevus

We report a case of plexiform neurofibroma developed under the overlying speckled lentiginous nevus, which occurred in a 20 year-old man. In this patient and his family no other signs of von Recklinghausens disease were found. Discussion is focussed on the fact that both plexiform neurofibroma and speckled lentigmous nevus, which represent a defect in the neural crest, occurred in the same area of the skin.

Two Cases of Cutaneous Leishmaniasis Treated with Itraconazole

Two patients with cutaneous leishmaniasis were treated with itraconazole. One patient was a 24-year-old man who had several erythematous papulonodules on the extremities for 1 month, which revealed cutaneous leishmaniasis, histopathologically. He was treated with itraconazole (200 mg/day) for 2 months. After treatment he showed clinical healing and the biopsy specimens no longer showed leishmania organisms. The other patient was a 27-year-old female who had several erythematous papulonodules on the face and neck for 3 months. The skin lesions revealed leishmania organisms in the tissue sections and culture media. She was also treated with itraconazole (200 mg/day) for 2 months. After treatment she also showed satisfying clinical healing and the biopsy specimens revealed no leishmania organisms. No specific side effects were encountered in both patients during the treatment. From these results, itraconazole is considered to be one of the promising anti-leishmanial drugs.