In vitro antimicrobial susceptibility of Propionibacterium acnes isolated from acne patients in northern Mexico

Background Antimicrobials are essential in acne therapy. In the last decades, Propionibacterium acnes has become resistant to different antibiotics. Objective To determine antimicrobial susceptibility patterns of P. acnes to frequently used drugs. Materials and methods Cutaneous lesion samples were obtained from 50 patients with acne vulgaris, which were cultured in anaerobic media to demonstrate the presence of P. acnes. After that, antimicrobial susceptibility tests to tetracycline, minocycline, doxycycline, erythromycin, azithromycin, clindamycin, trimethoprim/sulfamethoxazole (SXT) and levofloxacin were performed. Results In the general study group, resistance to azithromycin was 82%, the most prevalent one (P < 0.05), followed by trimethoprim/sulfamethoxazole (68%) and erythromycin (46%). On the other hand, all strains isolated were susceptible to minocycline. Resistance bias were similar when subgroups with and without the previous antimicrobial therapy were performed, finding a low prevalence of resistance to tetracyclines and levofloxacin in both groups. Conclusions In our region, P. acnes is highly resistant to azithromycin, SXT, erythromycin and clindamycin; and being very susceptible to minocycline, levofloxacin and tetracycline, in vitro in both groups: with and without the previous antibiotic use. To our knowledge, high resistance prevalence to azithromycin and SXT has never been reported.     

Positive effect of using calcipotriol ointment with narrow-band ultraviolet B phototherapy in psoriatic patients

BACKGROUND/PURPOSE: The successful use of narrow-band ultraviolet B (UVB) phototherapy for the management of psoriasis has prompted the examination of various combination treatments with narrow-band UVB. However, there have been contradictory reports on the effect of the calcipotriol-narrow-band UVB combination. This study was performed to compare the clinical efficacy of the calcipotriol-narrow-band UVB combination with narrow-band UVB alone. METHODS: Of the 28 psoriasis patients, 10 were treated with the calcipotriol-narrow-band UVB and 18 with narrow-band UVB alone. Phototherapy was done once daily three times a week and the dose was gradually increased in a stepwise fashion by 0.05 J/cm2. At the end of therapy, overall efficacy was classified according to the chosen grading system. RESULTS: On assessing the therapeutic results using the criteria selected, 90.0% patients (n = 9) in the calcipotriol-narrow-band UVB group and 61.1% patients (n = 11) in the narrow-band UVB group showed grade IV at the end of therapy. The calcipotriol-narrow-band UVB group showed more rapid improvement at the early stage. The final and total UVB dose were slightly lower in the calcipotriol-narrow-band UVB group but no significant difference was observed with respect to the total number of irradiations, duration of treatment, final UVB dose or total cumulative UVB dose required to reach grade IV in both groups (P > 0.05). The pattern of adverse effects was similar in both groups with a slightly higher frequency in the calcipotriol-narrow-band UVB group. CONCLUSION: Our results demonstrated that the total cumulative UVB dose required to reach grade IV was not significantly different in both groups, although it was slightly lower in the calcipotriol-narrow-band UVB group. However, a higher percentage of patients attained grade IV at the end of therapy in the combination group and this therapy was more effective in reducing the Psoriasis Area and Severity Index early in treatment. More studies are warranted to confirm these results.     

In vitro assessment of the bactericidal effect of low-power arsenium-gallium (AsGa) laser treatment

The objective of the present study was to perform an in vitro evaluation of the bactericidal action of a low-power arsenium-gallium (AsGa) laser at a wavelength of 904nm and energy density of 6 J/cm2. Ten petri dishes were seeded with Pseudomonas aeruginosa and another ten with Staphylococcus aureus. The dishes were then randomly divided into four groups with five plates in each group. Two groups were treated with AsGa laser once a day for 5 days, while the other two groups received no treatment. No halo of growth inhibition was found in any of the groups. It was therefore concluded that laser treatment (AsGa, 904nm, 6J/cm2) had no bactericidal effect.     

Incidence of acne vulgaris in patients with infantile acne

A group of patients who attended dermatology clinics in Northern Ireland between 1960 and 1970 with a diagnosis of infantile acne was compared with a similar age-matched control group of 160 medical students. The severity of the acne was judged according to the form of treatment required--topical treatment, systemic antibiotics or isotretinoin. The statistical power of this study is limited but there appears to be a trend towards higher incidence and greater severity of acne vulgaris in teenage years in patients with a history of infantile acne compared to their peers.     

Narrow-band ultraviolet B phototherapy in patients with recalcitrant nodular prurigo

Management of nodular prurigo has been less than satisfactory. Conventional therapies such as systemic antihistamines and topical steroids have not been particularly successful. The effects of narrow-band ultraviolet B (NB-UVB) phototherapy in the treatment of various inflammatory dermatoses have been proven, however, no data exist on the efficacy and the duration of remission in NB-UVB monotherapy for nodular prurigo. The aim of this study was to evaluate the effect of NB-UVB phototherapy on recalcitrant nodular prurigo. NB-UVB phototherapy was performed once a week on 10 patients with recalcitrant nodular prurigo. The initial dose was 0.4 J/cm(2), and the dose was increased by 0.1 J/cm(2) for each treatment. The treatment was performed until the eruption was almost clear. In each patient, a mean cumulative dose of 23.88 J/cm(2) was applied over a mean of 24.3 irradiations. The mean maximum daily dose of ultraviolet B was 1.2 +/- 0.4 J/cm(2). NB-UVB phototherapy notably improved the eruption of nodular prurigo in all patients. Follow up at 1 year revealed that only one patient had relapsed. The remaining nine patients continued to derive long-term benefits. NB-UVB phototherapy appears to be an effective treatment for recalcitrant nodular prurigo, offering long-term benefits in the majority of those treated.     

Protective effect of dl-alpha-tocopherol on the cytotoxicity of ultraviolet B against human skin fibroblasts in vitro

The effect of dl-alpha-tocopherol on ultraviolet light, 280-320 nm (UVB)-induced damage of human skin fibroblasts was studied by measuring the colony-forming ability, unscheduled DNA synthesis (UDS) and malondialdehyde (MDA) production. Regarding the cell toxicity, the values of the mean lethal dose (D0) of UV in fibroblast strains from 5 normal subjects were examined. D0 increased dose-dependently when the cells were cultured in the presence of dl-alpha-tocopherol at the concentration of 10-1000 micrograms/ml. UDS induced by 500 J/m2 UVB irradiation was not altered by treatment of 100 micrograms/ml dl-alpha-tocopherol. MDA did not increase after 500 J/m2 UVB irradiation in the fibroblasts cultured with 100 micrograms/ml dl-alpha-tocopherol, while MDA in the fibroblasts cultured without dl-alpha-tocopherol increased after irradiation. These results suggest that dl-alpha-tocopherol protects human skin fibroblasts against the cytotoxic effect of UVB, and its mechanism seems to be related to inhibition of UV-induced lipid peroxidation or to the antioxidation effect of dl-alpha-tocopherol.     

Impulsivity in patients with acne excoriee

Background

Impulsivity is the tendency to make decisions and act quickly without adequate planning and anticipating risks. Impulsivity is among the core symptoms of many psychiatric disorders. In addition, impulsivity can affect the course of various diseases shaped by behaviors.

Aims

This study aimed to evaluate the relationship between the presence of acne excoriee and different impulsivity dimensions.

Study Design

A case–control study.

Methods

Thirty patients with acne excoriee (AE+) and 30 acne vulgaris patients without excoriated lesions (AE-) enrolled in this study. Impulsivity was evaluated by The Barratt Impulsivity Scale (BIS). In addition, The Beck Anxiety Inventory, The Beck Depression Inventory, and The Skin Picking Scale were applied to assess the clinical characteristics of the participants.

Results

AE+ patients had higher non-planning subscale scores of BIS than AE- patients in this study. In addition, the acne-picking severity score determined by The Skin Picking Scale was positively correlated with non-planning subscale scores of BIS. There was no significant difference between the groups regarding the Beck Depression Inventory and Beck Anxiety Inventory.

Conclusions

These results indicate that AE patients have a lack of forethought. In other words, it has been shown that impulsive personality traits, which indicate a lack of planning for the future, may be associated with the acne-picking behavior of the patients.     

Eye protection for ultraviolet B phototherapy and psoralen ultraviolet A patients

Background/purpose: We tested eye protection used for phototherapy patients. The study also established current practice concerning eye protection in a sample of UK phototherapy units. Methods: The ultraviolet (UV) transmission spectra of 30 ‘UV protective’ contact lenses were measured at 5 nm intervals between 290 and 400 nm. Sunglasses, small UV goggles and UV visors were tested between 270 and 420 nm. We surveyed the use of eye protection during phototherapy in 78 UK phototherapy units. Results: All samples of sunglasses, eye protection goggles, visors and sunglasses comfortably passed previously published arbitrary limits of acceptability. Most contact lenses showed some protection in the UVB, but most had little or no UVA protection. Of 78 UK phototherapy units 21 (33%) use tinted goggles during UV exposures, two (3%) use a visor only, 28 (43%) use both and nine (14%) use clear plastic (probably polycarbonate) goggles. Conclusions: UV transmission for sunglasses and contact lenses is lower compared with samples tested 10 years ago. All samples of glasses, goggles and visors tested provided adequate protection in the UV range according to published arbitrary limits of acceptability. Most contact lenses did not provide significant UV protection in the UVA range.     

Efficacy of low-dose cyproterone acetate compared with minocycline in the treatment of acne vulgaris

A multi-centre controlled trial of low-dose cyproterone acetate (Diane®, Schering Health t are Ltd) compared with minocycline hydrochloride (Minocin®, Lederle Laboratories Ltd) in female patients with acne vulgaris has been undertaken. Seventy-eight patients completed the study. Over a 24-week treatment period, Diane and Minocin were found to be equally effective in reducing the lesion count for comedones, papules and pustules, and in the patients' subjective assessment of their skin. No significant changes in weight or blood pressure were found in either treatment group, and the number of patients reporting; side-effects was similar.     

Incidence of skin cancers in 3867 patients treated with narrow-band ultraviolet B phototherapy

Background  Narrow‐band ultraviolet B (NB‐UVB) phototherapy is a widely used treatment. Psoralen‐UVA photochemotherapy (PUVA) increases skin cancer risk and some animal studies have raised the possibility of an increased risk with NB‐UVB. The risk of skin cancer in humans following treatment with NB‐UVB is unknown. Objectives  This current analysis forms part of an ongoing study ultimately aiming to define the long‐term carcinogenic risk of NB‐UVB treatment in humans. Methods  Details of all patients receiving NB‐UVB treatment until 31/12/2002 in Tayside, Scotland, were accessed from a treatment database and linked to the Scottish Cancer Registry. Indirect standardization was used to compare skin cancer incidence in the study population with age and sex matched cancer registry data for the Tayside population. We also assessed the effect of NB‐UVB exposure treatment numbers on the risk of developing skin cancer. Results  Of 4690 records reviewed, 4665 were suitable for analysis with 3886 records linked with the cancer registry and 3867 followed‐up for at least 6 months before 31/12/02 (the date at which cancer registration was deemed to be complete). The median number of NB‐UVB treatments was 29 with 352 patients receiving ≥ 100 treatments. The study gave 24 753 person‐years of follow up. First skin cancers recorded in study patients were 27 basal cell carcinomas (BCC), seven squamous cell carcinomas (SCC) and six melanomas. No association was found between NB‐UVB exposure alone (without PUVA) and any skin cancer. For NB‐UVB and PUVA treated patients there was an association with BCC, with 27 BCCs found compared with 14·1 expected in the matched population. Conclusion  We found no significant association between NB‐UVB treatment and BCC, SCC or melanoma. There was a small increase in BCCs amongst those also treated with PUVA. These reassuring results do not demonstrate the early increase in skin cancers that was found associated with PUVA treatment. However, cautious interpretation is required as the cohort contained relatively few patients who had a high treatment number and because the slow evolution of skin cancers may result in a delayed incidence peak. Ongoing risk assessment is therefore essential.     

Remission behavior following low-dose 13-cis-retinoic acid in papulopustular acne

64 patients suffering from severe papulopustular acne previously resistant to therapy were treated with 13-cis retinoic acid (isotretinoin) at a dosage of 0.05, 0.1, or 0.2 mg/kg body weight for 20 weeks. After treatment, we performed follow-up examinations for 12 months concerning remission and side effects. After six months, more than half of the patients were free of relapses, even those treated with low doses, although there was a trend in favor of the 0.2 mg/kg body weight dose. According to lesion counts, the therapeutic effect of isotretinoin was even better after discontinuation of the drug. Mucocutaneous side effects disappeared within four to six weeks. In severe papulopustular acne, previously showing inadequate response to therapy, at least 0.2 mg/kg body weight isotretinoin should be given to ensure a good therapeutic result. These findings correspond with those observed in the initial reduction of lesions.     

In vitro assessment of the broad-spectrum ultraviolet protection of sunscreen products

BACKGROUND: There are considerable data to suggest that protection from solar ultraviolet (UV) radiation will reduce the risk of acute and chronic skin damage in humans. Whereas the sun protection factor (SPF) provides an index of protection against erythemally effective solar UV, largely confined to the UVB (290-320 nm) and short-wavelength UVA (320-340 nm) region, there is currently no agreed-upon method to measure broad-spectrum protection against long-wavelength UVA (340-400 nm). OBJECTIVE: The objective of these studies was to assess the potential of in vitro UV substrate spectrophotometry and subsequent calculation of the "critical wavelength" value as a measure of broad-spectrum UV protection and as a routine, practical procedure for classification of sunscreen products. METHODS: The spectral absorption of 59 commercially available sunscreen products and multiple experimental formulas with one or more UV filters was measured. Sunscreen product, 1 mg/cm(2), was applied to a hydrated synthetic collagen substrate, preirradiated with a solar simulator, and then subjected to UV substrate spectrophotometry. Multiple determinations from 5 independent samples per product were used to calculate the critical wavelength value, defined as the wavelength at which the integral of the spectral absorbance curve reached 90% of the integral from 290 to 400 nm. RESULTS: We found that a recognized long-wave UVA active ingredient such as titanium dioxide, zinc oxide, or avobenzone is a necessary but insufficient product requirement for achieving the highest proposed broad-spectrum classification, that is, critical wavelength of 370 nm or more. Although SPF and critical wavelength are largely independent of each other, UVA absorbance must increase commensurate with SPF to maintain the same critical wavelength value. Substrate spectrophotometry and the calculation of critical wavelength can readily account for sunscreen photostability by UV preirradiation. Finally, there is also a strong positive relationship between critical wavelength and a currently available in vivo measure of UVA protection. CONCLUSION: Determination of critical wavelength by means of UV substrate spectrophotometry provides a rapid, inexpensive, and reliable measure of broad-spectrum protection, which is largely independent of SPF, yet ensures long-wavelength UVA protection commensurate with SPF. The procedure provides a routine, sensitive means of differentiating and classifying sunscreen products and, importantly, obviates the need to subject volunteers to acute exposures of high-dose, nonterrestrial UV, the health risks of which are still poorly understood.     

An in vitro assessment of certain cellular and humoral immune functions in patients with chronic acne

Testing of cellular and humoral immune functions was performed on nineteen patients with chronic acne. Eight patients had no detectable abnormality of cellular function, seven had low neutrophil motility and six had depressed mitogen induced lymphocyte transformation. Eight patients had raised levels of serum IgE, seven had positive CRP values and one had a total IgA deficiency. Following propranolol therapy five patients showed no evidence of clinical improvement and nine showed significant clinical and immunological improvement.     

Fluorescence diagnostic imaging in patients with acne

Background: Orange‐red fluorescence in the follicle openings, induced by ultraviolet A light, originates from porphyrins, the metabolic products of Propionibacteria acnes. Purpose: To investigate the relationship of orange‐red follicular fluorescence with the severity of acne and the amount of sebum secretion. Methods: Twenty‐five volunteers were included. The severity of acne was rated on a 4‐point scale. The casual sebum level was measured using a Sebumeter and the follicular fluorescence was determined using the camera Visiopor. Results: Casual sebum level and the intensity of fluorescence (percentage of the area and number of orange‐red spots) were higher at the T zone than at the U zone in all patients regardless of their skin type. Sebum amount and area of fluorescence spots were significantly negative in correlation with the clinical grade of acne. There was a significant positive correlation between the orange‐red fluorescence and the casual sebum level. Conclusion: The orange‐red fluorescence showed stronger correlation with the presence of non‐inflammatory acne lesions (comedones) and high sebum amount than the presence of inflammatory acne lesions (pustules) and low sebum amount. The fluorescence diagnostic imaging could be useful in the objective evaluation and monitoring of treatment efficacy in subjects with acne‐prone skin and patients with acne.     

Lymphocyte subpopulations in patients with acne vulgaris

T- and B-lymphocyte subpopulations were measured in the peripheral blood of patients with varying severity of acne and in acne-free control subjects. Increased severity of acne correlated with an increased number of T lymphocytes, helper T cells and B cells, while the number of suppressor T cells remained normal and did not alter significantly. This evidence suggests that there is no lack of regulation of the immune response in acne patients.