Is minocycline therapy in acne associated with antineutrophil cytoplasmic antibody positivity? A cross-sectional study.

BACKGROUND: Minocycline (MN), one of the commonly prescribed therapies for acne, is known to be associated with autoimmune disorders including drug-induced lupus. However, data are sparse regarding the prevalence of autoimmune disease in acne or in patients with acne treated with MN. OBJECTIVES: To establish the prevalence of antinuclear antibodies (ANA), antineutrophil cytoplasmic antibodies (ANCA) and new autoimmune syndromes in an MN-exposed and unexposed population with acne. METHODS: In a cross-sectional study, 252 patients with acne vulgaris were assessed. Sixty-nine per cent had been exposed to MN at some point or were taking the drug at the time of the interview. Data recorded included duration of disease (acne) and drug history as well as possible side-effects of drugs, in particular joint symptoms (pain and swelling). In addition, blood was taken for ANA, ANCA, liver function tests and HLA analysis. RESULTS: There was no statistical difference in the prevalence of ANA positivity between patients exposed (13%) or not exposed (11%) to MN. However, higher titres of ANA (1/160 or higher) were found in the MN-exposed group (45% compared with 12% in the unexposed group). ANCA positivity was found in 7% of the MN-exposed group but no positivity was found in the unexposed cohort (P = 0.022). In 58% of cases, the ANCA detected were of the perinuclear pattern (p-ANCA) with myeloperoxidase specificity, and this finding was associated with clinical symptoms in the majority of cases. Two p-ANCA-positive patients were thought in retrospect to have developed a drug-induced lupus syndrome. CONCLUSIONS: ANA positivity is seen in patients with acne irrespective of exposure to MN; however, p-ANCA appear to be a serological marker for developing autoimmune disease in patients receiving MN.

Resolution of inflammatory acne vulgaris may involve regulation of CD4+ T-cell responses to Propionibacterium acnes.

BACKGROUND: Propionibacterium acnes has been strongly implicated in inflammatory acne. However, its role in the disease is unclear. It has been hypothesized that an immune response to P. acnes and/or P. acnes heat shock proteins (HSPs) may play a role in the pathogenesis of inflammatory acne. OBJECTIVES: To compare the cell-mediated immune response to P. acnes and HSPs in acne patients, nonacne controls and individuals with resolved acne. METHODS: The proliferative response of peripheral blood mononuclear cells (PBMC) from acne patients, resolved acne donors and healthy controls to P. acnes, P. acnes HSP60 and HSP70, and mycobacterial HSPs was assessed by lymphocyte transformation assay (LTA). The proliferative response of purified CD4+ T cells was further analysed by limiting dilution analysis (LDA). Contingency tables (G-test) were used to analyse the proportion of individuals in each group showing a positive proliferative response for LTA or data fitting single-hit kinetics for LDA. RESULTS: Analysis of stimulation of PBMC with P. acnes, P. acnes HSP60 and HSP70 in the LTA showed the proportion of positive responders to be independent of subject group. However, the proportion of acne patients with a positive response to mycobacterial HSPs was significantly higher than those for the other subject groups. Analysis of LDA data showed the proportion of resolved donors with responses to P. acnes fitting the single-hit kinetics model to be significantly lower than those of the other groups. There were no significant differences in responses to other antigens. CONCLUSIONS: The significantly lower proportion of resolved donors demonstrating a single-hit kinetics response to P. acnes by LDA may represent negative regulation of the CD4+ T-cell response to P. acnes in these subjects.

Temporal changes in sebum excretion and propionibacterial colonization in preadolescent children with and without acne.

BACKGROUND: It is generally accepted that the onset of sebum secretion occurs before puberty in boys and girls as a result of increasing androgen output during the adrenarche. Propionibacteria are part of the commensal skin flora and, in adults, are found in highest numbers in sebum-rich areas of skin such as the face and upper trunk. Previous studies investigating the association between sebum output and propionibacterial population densities have been cross-sectional and have been carried out mainly in adults. OBJECTIVES: The purpose of this study was to examine the association between the onset of sebum secretion and expansion of the propionibacterial flora in a population of early adolescent children aged between 5.5 and 12 years, and to evaluate the temporal relation between the two factors longitudinally. In addition, the study aimed to evaluate the change with age in sebaceous gland activity and propionibacterial colonization on the skin and in the nares between children who developed acne and those who did not. METHODS: Biannual examinations of volunteers included age, pubertal (Tanner) stage, weight and height, lesion counting on the face, propionibacterial colonization on the skin surface and in the nares and sebum secretion. A longitudinal analysis based on all observations of each subject throughout the study was applied to examine the change of sebaceous gland activity and propionibacterial colonization with age and pubertal stage. A generalized estimating equation was used with a 0.05 level of significance. RESULTS: The commencement of sebum production was asynchronous, with only a small number of follicles initially starting to secrete sebum onto the skin surface. The number of secreting follicles and the area of sebum increased with age and pubertal stage (P < 0.0001, P < 0.05, respectively). Numbers of propionibacteria on the skin tended to increase after the age of 9 years, but not significantly so. In contrast, numbers of propionibacteria in the nares increased significantly with age (P < 0.0001) but not with pubertal maturation. Children who developed acne had higher sebum output and propionibacterial densities with increasing age than children who did not develop acne. This effect was significant for the increase of total sebum area with age in pubertal children (P = 0.0023), the increase in number of secreting follicles with age (P = 0.020) in prepubertal children, and the increase in propionibacteria densities in the nares with age (P = 0.0005) in pubertal children. Sebaceous gland activity and propionibacterial numbers on the skin surface remained unchanged with increasing age in children who did not develop acne. Propionibacterial population densities in the nares increased with age regardless of the development of acne. CONCLUSIONS: Onset of sebum secretion and consequently expansion of the propionibacterial skin flora occur earlier in children who develop acne than in children of the same age and pubertal status who do not develop acne. These observations suggest that postponing the onset of sebum production or the expansion of the propionibacterial skin flora until after puberty may represent ways of preventing the disease or minimizing its severity. Determinants of propionibacterial colonization on the skin and in the nares may be different.

An observer-blind parallel-group, randomized, multicentre clinical and microbiological study of a topical clindamycin/zinc gel and a topical clindamycin lotion in patients with mild/moderate acne.

INTRODUCTION: A topical acne treatment in which clindamycin phosphate equivalent to 1% clindamycin is presented in a gel formulation has received marketing authorizations in a number of EU and non-EU countries. Clindamycin/zinc gel contains zinc acetate in a formulation that reduces systemic absorption of clindamycin through the skin. OBJECTIVES: To compare the efficacy and safety of a 1% clindamycin/zinc gel when applied to the face once daily or twice daily with a 1% clindamycin lotion applied twice daily for 16 weeks in patients with mild to moderate acne vulgaris. METHODS: This was a randomized, comparative, observer-blind, parallel-group, multicentre study involving 246 acne patients. RESULTS: The study demonstrated therapeutic similarity between clindamycin/zinc gel applied once and twice daily with clindamycin lotion applied twice daily. All three regimens produced a gradual and time-dependent reduction in inflamed lesions, non-inflamed lesions and overall grade. Side effects were similar and minimal, consisting predominantly of mild irritant dermatitis. All regimes produced a time-related significant reduction in skin surface and follicular Propionibacterium spp. and Micrococcaceae. The emergence of resistant strains was less than 5% and was similar with all three regimes. CONCLUSION: The equivalent efficacy and safety of clindamycin/zinc gel either once or twice daily to clindamycin lotion twice daily has been demonstrated. It is suggested that a treatment regime of one application per day may significantly enhance compliance and thus treatment success in acne patients.

Efficacy of oral isotretinoin in the control of skin and nasal colonization by antibiotic-resistant propionibacteria in patients with acne.

BACKGROUND: Skin colonization by antibiotic-resistant propionibacteria is commonplace among acne patients globally. Increasing attention is now being paid to how resistance rates might be reduced to preserve the future efficacy of antibiotics, especially erythromycin and clindamycin in acne therapy. OBJECTIVE: To assess the efficacy of oral isotretinoin in the control of antibiotic-resistant propionibacteria. METHODS: Acne patients (72 in the U.K., 62 in the U.S.A.) colonized with high numbers of antibiotic-resistant propionibacteria were sampled before, during and 12 weeks after oral isotretinoin therapy. Propionibacterial samples were collected from five acne-prone skin surface sites using a detergent scrub method and from the anterior nares using moistened swabs. Total and antibiotic-resistant propionibacteria were enumerated by viable counting on media with and without selective antibiotics. RESULTS: After 16 weeks of oral isotretinoin therapy, mean population densities of viable propionibacteria and variants resistant to erythromycin, clindamycin or tetracycline had fallen by more than 90% at all skin sites and in the nares. The sole exception was a smaller reduction in tetracycline-resistant strains on the lower back. In general, greater reductions were observed on skin than in the nares. By the end of the treatment period only three patients (all in Philadelphia) yielded no antibiotic-resistant strains from any site. Post-treatment, propionibacterial counts remained well below pretreatment levels but had begun to recover on the face and in the nares. The recovering propionibacterial population included both susceptible and resistant strains. Changes during and post-treatment at the two centres were similar but not identical. CONCLUSIONS: Oral isotretinoin effectively reduced skin and nasal colonization by antibiotic-resistant propionibacteria. However, viable populations of resistant isolates persisted post-treatment at multiple sites. Novel methods are required to eradicate antibiotic-resistant propionibacteria completely, especially from the nasal reservoir.

Objective assessment of compliance with treatments in acne.

BACKGROUND: Acne occurs in prepubertal individuals, teenagers and adults, and can have a devastating effect on self-esteem and social relationships. Whether an acne sufferer will seek treatment often depends, apart from the severity, on cultural and social aspects, which play a significant role in the attitude of the individuals and how they cope with the condition. Compliance with treatment regimen is an essential element in overall effectiveness of therapy. OBJECTIVES: To assess patient compliance in acne vulgaris. METHODS: In an open prospective study at a dermatology outpatient clinic, patients with acne, and on isotretinoin or conventional therapies, were examined and completed a questionnaire consisting of: (i) a brief medical and social history, (ii) a compliance assessment sheet, and (iii) the Dermatology Life Quality Index (DLQI). Patients were re-examined after 3 months and their actual treatment usage was directly assessed and compared with expected use. The objective medication adherence (Med Ad) was calculated as (actual treatment use/expected treatment use) x 100. The interview (self-report) Med Ad was obtained by direct questioning. To avoid influencing the behaviour of the subjects, they were not informed of the specific aim of the study: the Local Research Ethics Committee gave approval for this approach. Patient attendance was recorded by referring to the outpatient clinic appointment charts. RESULTS: Of 687 patients seen who fulfilled the inclusion criteria, 403 completed the study. The mean +/- SD overall objective Med Ad was 64.7 +/- 24% (range 0-111%). The mean +/- SD DLQI was 17.7 +/- 8.1 (range 2-30). There was a highly significant negative correlation (r = -0.87) between DLQI scores and Med Ad. The correlation between age and Med Ad was significantly negative (P < 0.01). Being female, married, employed and not paying for prescriptions were characteristics associated with increased Med Ad and a lower DLQI. Med Ad was greater for isotretinoin therapy and for first time usage of isotretinoin. The major reasons for missing treatment given by the patients were being fed up, forgetful or too busy. Smoking cigarettes and drinking alcohol resulted in reduced Med Ad. The mean +/- SD interview Med Ad was 93.9 +/- 5% (range 85-100%). CONCLUSIONS: The study demonstrates that a range of disease-related and social factors may influence compliance with treatment in acne. The inverse relationship between DLQI and Med Ad probably reflects the profound interaction of physical and psychological factors as well as perceived treatment failure.

Evaluation of a pre-operative staging protocol in the management of colorectal carcinoma.

OBJECTIVE: The optimum strategy for pre-operative staging of colorectal carcinoma (CRC) has yet to be defined. A protocol for staging CRC patients was set up in this hospital in 1998. The protocol included complete colonic visualization together with assessment of the liver and lung for potential metastatic disease. Pelvic imaging was required to assess the local spread of rectal tumours. Our aim was to evaluate prospectively this protocol. PATIENTS AND METHODS: Data from all patients diagnosed with primary CRC between January 1999 and December 2002 were prospectively collected and analysed. RESULTS: There were 295 patients; 56 (19%) patients presented as an emergency and were excluded. The study group consisted of 239 patients (206 had elective surgery and 33 had no resectional surgery). In the patients who presented electively; 88% had complete colonic imaging; 87% chest imaging; 90% had liver imaging; 91% of rectal tumours had pelvic imaging. Overall 75% of the elective patients completed the staging protocol. Reasons for incomplete staging were numerous and most were justifiable. Findings which influenced clinical management included alteration in surgical approach (14), lung metastases (7), primary lung cancers (2), definite liver metastases (25), possible liver metastases (8), neo-adjuvant radiotherapy required (27), advanced local disease (9) and other incidental findings (12). CONCLUSION: Our protocol influenced further management decisions in 39% of patients. Better stratification of patient care is possible, with the ultimate aim to avoid unnecessary surgery. However, complete staging is not always possible to perform.

Randomised controlled multiple treatment comparison to provide a cost-effectiveness rationale for the selection of antimicrobial therapy in acne.

OBJECTIVES: To determine the relative efficacy and cost-effectiveness of five of the most commonly used antimicrobial preparations for treating mild to moderate facial acne in the community; the propensity of each regimen to give rise to local and systemic adverse events; whether pre-existing bacterial resistance to the prescribed antibiotic resulted in reduced efficacy; and whether some antimicrobial regimens were less likely to give rise to resistant propionibacterial strains. DESIGN: This was a parallel group randomised assessor-blind controlled clinical trial. It was a pragmatic design with intention-to-treat analysis. All treatments were given for 18 weeks, after a 4-week treatment free period. Outcomes were measured at 0, 6, 12 and 18 weeks. SETTING: Primary care practices and colleges in and around Nottingham and Leeds, and one practice in Stockton-on-Tees, England. PARTICIPANTS: Participants were 649 people aged 12--39 years, all with mild to moderate inflammatory acne of the face. INTERVENTIONS: Study participants were randomised into one of five groups: 500 mg oral oxytetracycline (non-proprietary) twice daily (b.d.) + topical vehicle control b.d.; 100 mg oral Minocin MR (minocycline) once daily (o.d.) + topical vehicle control b.d.; topical Benzamycin (3% erythromycin + 5% benzoyl peroxide) b.d. + oral placebo o.d.; topical Stiemycin (2% erythromycin) o.d. + topical Panoxyl Aquagel (5% benzoyl peroxide) o.d. + oral placebo o.d., and topical Panoxyl Aquagel (5% benzoyl peroxide) b.d. + oral placebo o.d. (the active comparator group). MAIN OUTCOME MEASURES: The two primary outcome measures were: (1) the proportion of patients with at least moderate self-assessed improvement as recorded on a six-point Likert scale, and (2) change in inflamed lesion count (red spots). RESULTS: The best response rates were seen with two of the topical regimens (erythromycin plus benzoyl peroxide administered separately o.d. or in a combined proprietary formulation b.d.), compared with benzoyl peroxide alone, oxytetracycline (500 mg b.d.) and minocycline (100 mg o.d.), although differences were small. The percentage of participants with at least moderate improvement was 53.8% for minocycline (the least effective) and 66.1% for the combined erythromycin/benzoyl peroxide formulation (the most effective); the adjusted odds ratio for these two treatments was 1.74 [95% confidence interval (CI) 1.04 to 2.90]. Similar efficacy rankings were obtained using lesion counts, acne severity scores and global rating by assessor. Benzoyl peroxide was the most cost-effective and minocycline the least cost-effective regimen (ratio of means 12.3; difference in means -0.051 units/GBP, 95% CI -0.063 to -0.039). The efficacy of oxytetracycline was similar to that of minocycline, but at approximately one-seventh of the cost. For all regimens, the largest reductions in acne severity were recorded in the first 6 weeks. Reductions in disability scores using the Dermatology Quality of Life Scales were largest for both topical erythromycin-containing regimens and minocycline. The two topical erythromycin-containing regimens produced the largest reductions in the prevalence and population density of cutaneous propionibacteria, including antibiotic-resistant variants, and these were equally effective in participants with and without erythromycin-resistant propionibacteria. The clinical efficacy of both tetracyclines was compromised in participants colonised by tetracycline-resistant propionibacteria. None of the regimens promoted an overall increase in the prevalence of antibiotic-resistant strains. Systemic adverse events were more common with the two oral antibiotics. Local irritation was more common with the topical treatments, particularly benzoyl peroxide. Residual acne was present in most participants (95%) at the end of the study. CONCLUSIONS: The response of mild to moderate inflammatory acne to antimicrobial treatment in the community is not optimal. Only around half to two-thirds of trial participants reported at least a moderate improvement over an 18-week study period; extending treatment beyond 12 weeks increased overall benefit slightly. Around one-quarter dropped out when using such treatments, and 55% sought further treatment after 18 weeks. Topical antimicrobial therapies performed at least as well as oral antibiotics in terms of clinical efficacy. Benzoyl peroxide was the most cost-effective and minocycline the least cost-effective therapy for facial acne. The efficacy of all three topical regimens was not compromised by pre-existing propionibacterial resistance. Benzoyl peroxide was associated with a greater frequency and severity of local irritant reactions. It is suggested that the use of a combination of topical benzoyl peroxide and erythromycin gives less irritation and better quality of life. There was little difference between erythromycin plus benzoyl peroxide administered separately and the combined proprietary formulation in terms of efficacy or local irritation, except that the former was nearly three times more cost-effective. The data on cost-effectiveness, and outcomes in patients with resistant propionibacterial floras, did not support the first line use of minocycline for mild to moderate inflammatory acne of the face. Three priority areas for clinical research in acne are: defining end-points in acne trials (i.e. what is a satisfactory outcome?); developing and validating better patient-based measures for assessing treatment effects on facial and truncal acne; and exploring patient characteristics that may modify treatment effects (efficacy and tolerability).

Topical aminolaevulinic acid-photodynamic therapy for the treatment of acne vulgaris: a study of clinical efficacy and mechanism of action.

BACKGROUND: Acne affects 83-95% of 16-year-olds of both sexes, and many seek help from a clinician. Emerging problems with conventional acne treatments, specifically antibiotic resistance of Propionibacterium acnes and fears over the safety and tolerance of oral isotretinoin, create a demand for novel treatment modalities in acne. OBJECTIVES: To study the efficacy of aminolaevulinic acid-photodynamic therapy (ALA-PDT) in the treatment of acne and to identify the mode of action, looking specifically at the effects on surface numbers of P. acnes and on sebum excretion. METHODS: Ten patients (nine men and one woman, age range 16-40 years) with mild to moderate acne on their backs were recruited. Each patient's back was marked with four 30-cm2 areas of equal acne severity. Each site was then randomly allocated to either ALA-PDT treatment, light alone, ALA alone or an untreated control site. At baseline, numbers of inflammatory and noninflammatory acne lesions were counted, sebum excretion measured by Sebutapes (CuDerm, Dallas, TX, U.S.A.) and surface P. acnes swabs performed. ALA cream (20% in Unguentum Merck) was applied under occlusion to the ALA-PDT and ALA alone sites for 3 h. Red light from a diode laser was then delivered to the ALA-PDT and light alone sites (635 nm, 25 mW cm(-2), 15 J cm(-2)). Each patient was treated weekly for 3 weeks. At each visit acne lesion counts were performed and 3 weeks following the last treatment sebum excretion rates and P. acnes swabs were repeated. RESULTS: There was a statistically significant reduction in inflammatory acne lesion counts from baseline after the second treatment at the ALA-PDT site but not at any of the other sites. No statistically significant reduction in P. acnes numbers or sebum excretion was demonstrated at any sites including the ALA-PDT site. CONCLUSIONS: ALA-PDT is capable of clinically improving acne. An alternative mode of action for ALA-PDT other than direct damage to sebaceous glands or photodynamic killing of P. acnes is suggested from the results of this study.

Inflammation in acne scarring: a comparison of the responses in lesions from patients prone and not prone to scar.

BACKGROUND: Many patients with inflammatory acne suffer from significant scarring, which is disfiguring and difficult to treat. A cell-mediated immune response is considered to be involved in the pathogenesis of acne, although the extent of this response has been found to differ among patients. OBJECTIVE: To assess whether there were differences in the cell-mediated immune responses at different time points in inflamed lesion development and resolution in patients who were prone (S patients) and those with the same degree of inflamed acne who were not prone (NS patients) to develop scarring. METHODS: Cellular and vascular markers were investigated using standard immunohistochemical techniques on biopsies of inflamed lesions of known duration, i.e. < 6 h (n = 14), 24 h (n = 14), 48 h (n = 10), 72 h (n = 10) and 6-7 days (n = 11) from the backs of acne patients. RESULTS: In early lesions from NS patients there was a large influx of CD4+ T cells, macrophages and Langerhans cells with a high number of cells expressing HLA-DR. Also there was significant angiogenesis and vascular adhesion molecule expression. Cell recruitment peaked in 48 h lesions, after which leucocyte numbers decreased and vascular activity returned to normal. Of the T cells, only 50% were memory/effector (CD45RO+) and naive (CD45RA+) cells, while the remainder were unclassified (CD45RO-, CD45RA-). In early lesions from S patients, CD4+ T cell numbers were smaller, although a high proportion were skin homing memory/effector cells. Langerhans cell numbers and cellular HLA-DR expression were low, while numbers of macrophages, blood vessels and vascular adhesion molecules were high. In resolving lesions angiogenesis remained high, with a further influx of macrophages and skin homing memory/effector cells and increased cellular HLA-DR expression. CONCLUSIONS: The cellular infiltrate was large and active with a greater nonspecific response (few memory T cells) in early lesions of NS patients, which subsided in resolution. In contrast, a predominantly specific immune response was present in S patients, which was initially smaller and ineffective, but was increased and activated in resolving lesions. Such excessive inflammation in healing tissue is conducive to scarring and suggests that the use of topical anti-inflammatory treatments would be appropriate for these patients.

Retrospective survey of serum lipids in patients receiving more than three courses of isotretinoin.

Isotretinoin is well recognised to cause hyperlipidaemia. This is most obvious during the second month of a 4-month course. Since there are no long-term data on lipid profiles, we have identified 30 subjects who have received 3 or more courses of isotretinoin. They had been exposed to a median of 24.5 months (range 12-103) isotretinoin therapy with a median total cumulative dose of 350 mg/kg (range 152-1221). The median serum cholesterol pre-treatment was 4.6 mmol/L (range 3-6.4). This compared to a median of 4.5 mmol/L (range 3-6.4) just prior to starting the final course. The median triglyceride levels before treatment and pre-final course were 0.8 mmol/L (range 0.3-1.7) and 0.92 mmol/L (range 0.4-2.6) respectively, indicating no significant change in cholesterol or triglyceride concentrations when measured prior to the first and last courses. In addition there was no correlation between cholesterol or triglyceride concentration before the final course of isotretinoin and the total cumulative dose of isotretinoin. We conclude that there appears to be little risk of causing hyperlipidaemia by prolonged therapy with isotretinoin in patients with acne.

Antibiotic-resistant acne: lessons from Europe.

BACKGROUND: Propionibacterium acnes and P. granulosum are widely regarded as the aetiological agents of inflammatory acne. Their proliferation and metabolism are controlled using lengthy courses of oral and/or topical antibiotics. Despite numerous reports of skin colonization by antibiotic-resistant propionibacteria among acne patients, accurate prevalence data are available only for the U.K. OBJECTIVES: To determine the prevalence of skin colonization by antibiotic-resistant propionibacteria among acne patients and their contacts from six European centres. METHODS: Skin swabs were collected from 664 acne patients attending centres in the U.K., Spain, Italy, Greece, Sweden and Hungary. Phenotypes of antibiotic-resistant propionibacteria were determined by measuring the minimum inhibitory concentrations (MIC) of a panel of tetracycline and macrolide, lincosamide and streptogramin B (MLS) antibiotics. Resistance determinants were characterized by polymerase chain reaction (PCR) using primers specific for rRNA genes and erm(X), followed by nucleotide sequencing of the amplified DNA. RESULTS: Viable propionibacteria were recovered from 622 patients. A total of 515 representative antibiotic-resistant isolates and 71 susceptible isolates to act as control strains were characterized phenotypically. The prevalence of carriage of isolates resistant to at least one antibiotic was lowest in Hungary (51%) and highest in Spain (94%). Combined resistance to clindamycin and erythromycin was much more common (highest prevalence 91% in Spain) than resistance to the tetracyclines (highest prevalence 26.4% in the U.K.). No isolates resistant to tetracycline were detected in Italy, or in Hungary. Overall, there were strong correlations with prescribing patterns. Prevalence of resistant propionibacteria on the skin of untreated contacts of the patients varied from 41% in Hungary to 86% in Spain. Of the dermatologists, 25 of 39 were colonized with resistant propionibacteria, including all those who specialized in treating acne. None of 27 physicians working in other outpatient departments harboured resistant propionibacteria. CONCLUSIONS: The widespread use of topical formulations of erythromycin and clindamycin to treat acne has resulted in significant dissemination of cross-resistant strains of propionibacteria. Resistance rates to the orally administered tetracycline group of antibiotics were low, except in Sweden and the U.K. Resistant genotypes originally identified in the U.K. are distributed widely throughout Europe. Antibiotic-resistant propionibacteria should be considered transmissible between acne-prone individuals, and dermatologists should use stricter cross-infection control measures when assessing acne in the clinic.

Comedogenesis: some aetiological, clinical and therapeutic strategies.

Hypercornification is an early feature of acne and usually precedes inflammation. It is associated with ductal hyperproliferation, and there are many controlling factors such as androgens, retinoids, sebum composition and cytokines. Cycling of normal follicles and of comedones may explain the natural resolution of comedones and, in the longer term, resolution of the disease itself. There is a need to tailor treatment according to comedonal type. Suboptimal therapy can often result from inappropriate assessments of comedones, especially microcomedones, sandpaper comedones, submarine comedones and macrocomedones. Macrocomedones can produce devastating acne flares, particularly if patients are inappropriately prescribed oral isotretinoin. Gentle cautery under topical local anaesthesia is a useful therapy in the treatment of such lesions. The newer retinoids and new formulations of all-trans-retinoic acid show a better benefit/risk ratio.

Prevalence of antibiotic-resistant propionibacteria on the skin of acne patients: 10-year surveillance data and snapshot distribution study.

BACKGROUND: Cutaneous propionibacteria are implicated in acne pathogenesis, although their exact role in the genesis of inflammation is still poorly understood. Agents, including antibiotics, that reduce the numbers of propionibacteria on skin are therapeutic. Resistance in the target organism is a well-recognized consequence of antibiotic therapy for acne but formal prevalence and distribution data are lacking. OBJECTIVES: To monitor the prevalence of skin colonization by antibiotic-resistant propionibacteria in acne patients attending the dermatology out-patient clinic at Leeds General Infirmary over a 10-year period beginning in 1991, and to examine the distribution of resistant strains on acne-prone skin and in the nares. METHODS: Propionibacterial samples were obtained from the skin surface of the worst affected site (usually the face) of 4274 acne patients using a moistened swab. The swab was used to inoculate agar plates with and without selective antibiotics. After anaerobic incubation at 37 degrees C for 7 days, the amount of growth in the presence of each antibiotic was scored on a scale from 0 to 5+. A small number of patients (72) were selected for more detailed quantitative sampling at six different sites to examine the distribution of resistant propionibacteria on acne-prone skin and in the anterior nares. RESULTS: The proportion of patients carrying strains resistant to one or more commonly used antiacne antibiotics rose steadily from 34.5% in 1991 to a peak of 64% in 1997. The prevalence dropped to 50.5% during 1999 and then rose again to 55.5% in 2000. Resistance to erythromycin was the most common and the majority of erythromycin-resistant strains were cross-resistant to clindamycin. Resistance to tetracyclines was less common in all years and with little increase over time. The more detailed quantitative study in 72 patients showed that population densities of resistant propionibacteria varied considerably between sites and between individuals. Almost invariably, patients were colonized with resistant strains at multiple sites, including the nares. CONCLUSIONS: Skin colonization with antibiotic-resistant propionibacteria is much more common now than a decade ago. Resistant propionibacteria are widely distributed on acne-prone skin and in the nares. This suggests that they will be very difficult to eradicate using existing therapeutic regimens, especially from the nasal reservoir.

Human beta defensin-1 and -2 expression in human pilosebaceous units: upregulation in acne vulgaris lesions.

A rich residential microflora is harboured by the distal outer root sheath of the hair follicle and the hair canal - normally without causing skin diseases. Although the basic mechanisms involved in the development of inflammation during acne vulgaris remain unclear, microbial agents might play an important role in this process. In this study we have analyzed by in situ hybridization and immunohistochemistry the expression patterns of two antimicrobial peptides, human beta defensin-1 and human beta defensin-2, in healthy human hair follicles as well as in perilesional and intralesional skin of acne vulgaris lesions such as comedones, papules, and pustules. Strong defensin-1 and defensin-2 immunoreactivity was found in all suprabasal layers of the epidermis, the distal outer root sheath of the hair follicle, and the pilosebaceous duct. Marked defensin-1 and defensin-2 immunoreactivity was also found in the sebaceous gland and in the basal layer of the central outer root sheath including the bulge region. The majority of acne biopsies displayed a marked upregulation of defensin-2 immunoreactivity in the lesional and perilesional epithelium - in particular in pustules - and a less marked upregulation of defensin-1 immunoreactivity. The upregulation of beta-defensin expression in acne vulgaris lesions compared to controls suggests that beta-defensins may be involved in the pathogenesis of acne vulgaris.