Cloning, nucleotide sequencing, and functional analysis of a novel, mobile cluster of biodegradation genes from Pseudomonas aeruginosa strain JB2.

We have identified in Pseudomonas aeruginosa strain JB2 a novel cluster of mobile genes encoding degradation of hydroxy- and halo-aromatic compounds. Nineteen open reading frames were located and, based on sequence similarities, were putatively identified as encoding a ring hydroxylating oxygenase (hybABCD), an ATP-binding cassette-type transporter, an extradiol ring-cleavage dioxygenase, transcriptional regulatory proteins, enzymes mediating chlorocatechol degradation, and transposition functions. Expression of hybABCD in Escherichia coli cells effected stoichiometric transformation of 2-hydroxybenzoate (salicylate) to 2,5-dihydroxybenzoate (gentisate). This activity was predicted from sequence similarity to functionally characterized genes, nagAaGHAb from Ralstonia sp. strain U2 (S. L. Fuenmayor, M. Wild, A. L. Boyes, and P. A. Williams, J. Bacteriol. 180:2522-2530, 1998), and is the second confirmed example of salicylate 5-hydroxylase activity effected by an oxygenase outside the flavoprotein group. Growth of strain JB2 or Pseudomonas huttiensis strain D1 (an organism that had acquired the 2-chlorobenzoate degradation phenotype from strain JB2) on benzoate yielded mutants that were unable to grow on salicylate or 2-chlorobenzoate and that had a deletion encompassing hybABCD and the region cloned downstream. The mutants' inability to grow on 2-chlorobenzoate suggested the loss of additional genes outside of, but contiguous with, the characterized region. Pulsed-field gel electrophoresis revealed a plasmid of >300 kb in strain D1, but no plasmids were detected in strain JB2. Hybridization analyses confirmed that the entire 26-kb region characterized here was acquired by strain D1 from strain JB2 and was located in the chromosome of both organisms. Further studies to delineate the element's boundaries and functional characteristics could provide new insights into the mechanisms underlying evolution of bacterial genomes in general and of catabolic pathways for anthropogenic pollutants in particular.

Primary multiple miliary osteoma cutis and exogenous ochronosis.

Multiple miliary osteoma cutis (MMOC), a rare disorder characterized by the appearance of numerous bony nodules on the face, was initially classified as a consequence of severe, long-standing acne vulgaris. However, several cases have now been described in patients with no preceding history of acne or other inflammatory conditions. We report such a case of primary MMOC in a 75-year-old African American woman and highlight the differences between these conditions. We also note the incidental histologic finding of exogenous ochronosis, which, in our case, indicates the patient's use of hydroquinone-containing bleaching creams in an attempt to treat the disorder.

A unique variant of Darier's disease.

A 45-year-old black woman presented with a chief complaint of an increasing number of "light spots" on her face, upper trunk, and legs. She had a 4-year history of a pruritic eruption on the dorsum of her hands. The eruption was particularly pruritic in the summer months. Other family members, including her sister and her daughters, reportedly had a similar dermatologic problem. The patient had been previously evaluated and biopsied by another dermatologist. The earlier biopsy was nondiagnostic, however, and she presented for further evaluation of this problem. On physical examination, the patient had hypopigmented macules along her jawline (Fig. 1), lateral neck, and upper chest. She had similar hypopigmented macules on her thighs. She had hyperkeratosis of the palmoplantar surface of her hands and feet. The dorsum of her hands had numerous coalescing, shiny, flat-topped, hypopigmented papules (Fig. 2), and several of her fingernails had distal, V-shaped notching. A punch biopsy from a papule on the dorsum of her hand was obtained. The epidermis had corps ronds present with focal areas of acantholysis above the basal layer (Fig. 3). The dermis had sparse, superficial, perivascular infiltrates composed of lymphocytes and histiocytes. These changes were consistent with our clinical diagnosis of Darier's disease (keratosis follicularis).

A large-scale North American study of fungal isolates from nails: the frequency of onychomycosis, fungal distribution, and antifungal susceptibility patterns.

BACKGROUND: Onychomycosis, a fungal infection of the nail bed, is responsible for up to 50% of nail disorders. Although several surveys have been conducted in different parts of the world, there have been no multicenter epidemiologic surveys of onychomycosis in North America. OBJECTIVE: A 12-center study was undertaken to (1) determine the frequency of onychomycosis, (2) identify organisms recovered from the nails, and (3) determine the antifungal susceptibility of isolates. METHODS: A total of 1832 subjects participated in this study and completed a comprehensive questionnaire, and nail clippings were collected for potassium hydroxide examination and culturing. RESULTS: The frequency of onychomycosis, as defined by the presence of septate hyphae on direct microscopy and/or the recovery of a dermatophyte, was found to be 13.8%. In general, the dermatophyte isolates were susceptible to the antifungals tested. CONCLUSION: Because of the limited number of large-scale studies, the baseline incidence is not firmly established. However, the higher frequency of onychomycosis in this study may confirm the suspected increase in incidence of disease in North America.

Oral therapy of common superficial fungal infections of the skin.

Although superficial fungal infections of the skin often respond to topical agents, systemic therapy is sometimes necessary. This article gives a review of the effectiveness of the oral antifungal agents fluconazole, itraconazole, and terbinafine in the treatment of pityriasis versicolor, tinea corporis/cruris, and tinea pedis. Four hundred milligrams fluconazole as a single dose and 200 mg itraconazole daily for 5 to 7 days were effective in the treatment of pityriasis versicolor; terbinafine taken orally appears to be ineffective in pityriasis versicolor. Tinea corporis and tinea cruris were effectively treated by 50 to 100 mg fluconazole daily or 150 mg once weekly for 2 to 3 weeks, by 100 mg itraconazole daily for 2 weeks or 200 mg daily for 7 days, and by 250 mg terbinafine daily for 1 to 2 weeks. Tinea pedis has been effectively treated with pulse doses of 150 mg fluconazole once weekly, with 100 mg itraconazole daily for 2 weeks or 400 mg daily for 1 week, and with 250 mg terbinafine daily for 2 weeks.

Telemedicine evaluation of cutaneous diseases: a blinded comparative study.

BACKGROUND: Numerous telemedicine programs have been created in the United States, but studies documenting the fidelity and effectiveness of telemedicine for evaluation of skin diseases are lacking. OBJECTIVE: We attempted to determine the percentage of encounters in which two different dermatologists, one using telemedicine and one on-site, could independently arrive at the same primary diagnosis. METHODS: Two clinical telemedicine sites linked through the Georgia Statewide Telemedicine Program were used in this study of 60 patients with skin problems. One dermatologist evaluated the patients on telemedicine (interactive television) and a second then took the patients into a separate examination room and evaluated them on-site. Each investigator recorded their diagnoses with no discussion with each other. As a control group, the investigators independently and in a blinded fashion (to each other's diagnoses) recorded diagnoses for a group of patients from a third dermatologist's clinic. Raw data were evaluated and classified by this third dermatologist who assigned diagnoses to categories of complete agreement, partial agreement, or disagreement. RESULTS: There were no significant differences with regard to disagreement. However, there was a higher probability of complete agreement between the two dermatologists when each examined the patient on-site and in person than when one evaluated the patient on telemedicine and one examined the patient on-site and in person. CONCLUSION: Our results suggest that telemedicine is an effective means of diagnosing cutaneous diseases. However, because partial interobserver agreement on diagnoses was greater for the telemedicine group than for the control group (p < 0.05), it is likely that optimum use of medical assistants at the remote site will be necessary to increase the likelihood of complete agreement on diagnoses among dermatologists using interactive television.

Butenafine 1% cream in the treatment of tinea cruris: a multicenter, vehicle-controlled, double-blind trial.

BACKGROUND: Butenafine hydrochloride, a potent antifungal agent related to the allylamines, has been used in Japan for treating various cutaneous mycoses including tinea cruris. OBJECTIVE: We compared the safety and efficacy of butenafine hydrochloride and its vehicle when used once daily for 2 weeks to treat tinea cruris. METHODS: Patients (n = 93) with tinea cruris and a positive potassium hydroxide examination and mycologic culture were enrolled. Of the 76 patients assessed for efficacy, 37 applied butenafine and 39 applied vehicle once daily for 2 weeks. Assessments were made at the end of the 2-week treatment period and 4 weeks after the end of treatment. RESULTS: Patients in the butenafine group had a higher mycologic cure rate by day 7 (66% vs 13%, p < 0.0001), with marked improvement 4 weeks after the end of treatment (81% vs 13%, p < 0.0001). They also had a higher rate of effective treatment at day 7 (29% vs 5%, p < 0.01) and at 4 weeks after treatment (73% vs 5%, p < 0.0001). Adverse events definitely related to butenafine treatment were limited to one case of burning sensation after application. CONCLUSION: Butenafine applied once daily for 2 weeks is effective in treating tinea cruris. The proportion of patients cured increased between the end of treatment and 4 weeks after treatment.

Ocular rosacea. Signs, symptoms, and tear studies before and after treatment with doxycycline.

OBJECTIVE: To examine ocular signs, symptoms, and results of tear analysis in patients with cutaneous rosacea before, during, and after doxycycline therapy. DESIGN: Before-after trial. SETTING: General community. PATIENTS OR OTHER PARTICIPANTS: Thirty-nine patients with cutaneous rosacea underwent dermatologic and ocular examinations, testing of tear break-up time, and Schirmer testing at baseline and 4, 8, and 12 weeks. Six patients did not complete the study. Baseline tear break-up time and results of Schirmer test were compared with those of 13 patients without rosacea who were matched for age and sex. INTERVENTION: Patients with rosacea were given doxycycline, 100 mg daily for 12 weeks. MAIN OUTCOME MEASURE: Statistically significant (P, .05) improvement in tear break-up time. RESULT: The most frequent ocular symptoms were dryness, itching, blurred vision, and photosensitivity, all of which improved significantly with treatment. All patients had signs of ocular disease, most commonly erythema and telangiectasia, meibomian gland dysfunction, and ciliary base injection. Significant improvement (P,.05) for scales, erythema and telangiectasia, ciliary base injection, bulbar injection, papillary hypertrophy, and punctate epithelial erosions was seen. Average tear break-up time for the patients with rosacea was 5.7 seconds, which improved to 10.8 seconds after 12 weeks of treatment (P = .007). Baseline tear break-up time was significantly lower than for the comparison group of normal subjects (P = .001). There was no correlation between severity of cutaneous disease and ocular disease. CONCLUSIONS: All patients with cutaneous rosacea had some degree of ocular involvement. Tear break-up time is abnormal in patients with rosacea. Ocular erythema and telangiectasia, meibomian gland dysfunction, and short tear break-up time in patients with cutaneous rosacea are indicators of ocular rosacea. Doxycycline, 100 mg daily, will improve ocular disease and increase the tear break-up time.

Effects of selenium supplementation for cancer prevention in patients with carcinoma of the skin. A randomized controlled trial. Nutritional Prevention of Cancer Study Group.

OBJECTIVE: To determine whether a nutritional supplement of selenium will decrease the incidence of cancer. DESIGN: A multicenter, double-blind, randomized, placebo-controlled cancer prevention trial. SETTING: Seven dermatology clinics in the eastern United States. PATIENTS: A total of 1312 patients (mean age, 63 years; range, 18-80 years) with a history of basal cell or squamous cell carcinomas of the skin were randomized from 1983 through 1991. Patients were treated for a mean (SD) of 4.5 (2.8) years and had a total follow-up of 6.4 (2.0) years. INTERVENTIONS: Oral administration of 200 microg of selenium per day or placebo. MAIN OUTCOME MEASURES: The primary end points for the trial were the incidences of basal and squamous cell carcinomas of the skin. The secondary end points, established in 1990, were all-cause mortality and total cancer mortality, total cancer incidence, and the incidences of lung, prostate, and colorectal cancers. RESULTS: After a total follow-up of 8271 person-years, selenium treatment did not significantly affect the incidence of basal cell or squamous cell skin cancer. There were 377 new cases of basal cell skin cancer among patients in the selenium group and 350 cases among the control group (relative risk [RR], 1.10; 95% confidence interval [CI], 0.95-1.28), and 218 new squamous cell skin cancers in the selenium group and 190 cases among the controls (RR, 1.14; 95% CI, 0.93-1.39). Analysis of secondary end points revealed that, compared with controls, patients treated with selenium had a nonsignificant reduction in all-cause mortality (108 deaths in the selenium group and 129 deaths in the control group [RR; 0.83; 95% CI, 0.63-1.08]) and significant reductions in total cancer mortality (29 deaths in the selenium treatment group and 57 deaths in controls [RR, 0.50; 95% CI, 0.31-0.80]), total cancer incidence (77 cancers in the selenium group and 119 in controls [RR, 0.63; 95% CI, 0.47-0.85]), and incidences of lung, colorectal, and prostate cancers. Primarily because of the apparent reductions in total cancer mortality and total cancer incidence in the selenium group, the blinded phase of the trial was stopped early. No cases of selenium toxicity occurred. CONCLUSIONS: Selenium treatment did not protect against development of basal or squamous cell carcinomas of the skin. However, results from secondary end-point analyses support the hypothesis that supplemental selenium may reduce the incidence of, and mortality from, carcinomas of several sites. These effects of selenium require confirmation in an independent trial of appropriate design before new public health recommendations regarding selenium supplementation can be made

Childhood granulomatous periorificial dermatitis.

A case of childhood granulomatous periorificial dermatitis is described. This disorder occurs predominantly in prepubertal black children and is characterized by a monomorphous, papular eruption occurring around the mouth, nose, and eyes. It is benign and self-limited. Treatment may include topical metronidazole in young patients and tetracycline in those over 8 years of age.

Recent developments in antifungal therapy.

There have been many advances during the past few years relating to the treatment of superficial fungal infections. This article focuses on recent developments, particularly in oral therapy, but in topical therapy as well. First, the newer agents (especially fluconazole, itraconazole, and terbinafine) are reviewed, and then the use of these agents in many disorders is discussed, with emphasis on tinea corporis or cruris, tinea pedis, tinea capitis, and onychomycosis.

Antibiotic prophylaxis in cutaneous surgery.

BACKGROUND: Postoperative wound infections, endocarditis, and late contamination of prosthetic implants are potential complications of cutaneous surgery. OBJECTIVE: To review current American Heart Association guidelines and their application to cutaneous surgery, and to determine how practicing physicians approach this problem. METHOD: Surveys were sent to dermatologists to determine what kind of preoperative screening was being done and how antibiotics were being used. RESULTS: The most common indications for prophylaxis were manipulation of infected tissue in patients undergoing any procedure, and any procedure in a patient with a prosthetic heart valve. Some respondents used antibiotic prophylaxis for all procedures, while others never used antibiotics in any surgical procedure. Cephalosporins and erythromycin were the most commonly used antibiotics and they were usually given orally, one dose before and one dose after surgery. CONCLUSION: Scientific literature supports the use of antibiotic prophylaxis for endocarditis in two situations: 1) surgical procedures on infected tissue in patients with a high risk cardiac lesion; and 2) any surgical procedure in a patient with a prosthetic heart valve. Our survey suggests that the majority of dermatologists obtain pertinent medical history and use appropriate antibiotic prophylaxis in these two situations. But the survey also suggests that antibiotic prophylaxis is used in a variety of situations where indications for use are not as clear, and sometimes prophylaxis is not used when it should be.