Nobukazu Hayashi

There are few clinical studies which compare the efficacy and patient satisfaction for oral antibiotics to treat inflammatory acne. To clarify the difference between oral antibiotics, acne patients with moderate to severe inflammatory eruptions were randomized into three groups, and each patient was given minocycline (MINO), roxithromycin (RXM) or faropenem (FRPM) for 4 weeks, followed by 4 weeks of observation without any oral antibiotics. We estimated the reduction rate of inflammatory lesion counts, the scale of Skindex-16 which represents patient quality of life (QOL), and minimum inhibitory concentrations required to inhibit the growth of 90% of Propionibacterium acnes isolated from acne patients (MIC(90) ). In all three groups, inflammatory lesion counts, and emotional and total score of Skindex-16 were significantly improved (P<0.05) after 4 weeks treatment, and these effects were maintained for the following 4 weeks. Dizziness/nausea in two patients (4.1%) of the MINO group and diarrhea in three patients (5.9%) of the FRPM group were observed. There was no significant difference of percentage reduction in inflammatory lesion counts and incident rates of side-effects between these three oral antibiotics. MIC(90) of MINO was 0.25 μg/mL before and after treatment, but MIC(90) of RXM had increased from 0.25 μg/mL to more than 32 μg/mL after treatment. MIC(90) of FRPM was 0.06 μg/mL or less for all strains before and after treatment. Our randomized controlled clinical trial suggested that MINO, RXM and FRPM were efficient to improve inflammatory acne and patient QOL, and there was no significant difference between them.

Recently, we established an acne severity classification that is based on scientific evidence. Our classification allows three different methods for grading, which include general impression of consulted dermatologist, photograph-based estimation by independent experts, and grading by lesion counting. In our classification, we proposed standard photographs for the estimation of general severity to adjust the basis of judgments. In this study, we evaluated the validity of our classification. We made questionnaires of acne severity using acne patients' photographs, which were selected from the collection of representative photographs of our classification. Participants answered these questionnaires before and after our presentations about our classification of acne severity. We identified the conformity rate with our consensus decision. The results revealed that average conformity rates were raised from 67.0% to 88.9% among Japanese dermatologists and from 68.0% to 79.8% among Korean ones. These data show the adequacy of both our grading system itself and its presentation. We believe our classification will be one of the most effective and reasonable grading systems to classify acne severity.

For the epidemiological surveys and evaluations of therapy, it is essential to evaluate the severity of diseases. There are several reported methods of assessment for acne severity including lesion counting, comparison of the patient's to a photographic standard and comparison of the patient's to a text description. But all of these are based on opinions of specialists. In this study, we attempted to make an evidence‐based grading criteria for acne severity, which was expected to yield consents from most dermatologists. The dermatologists consulted classified the global severity of acne patients without any standard and then counted the numbers of eruptions. Three independent expert dermatologists graded the photographs of these patients. We compared the verdicts of the consulted dermatologist and three experienced dermatologists, and analyzed the relationships between these classifications and numbers of eruptions. Our results showed that most of the dermatologists have similar latent recognitions of acne severity. We selected representative photographs as standards, which would contribute to making adjustments for judgments. Global classifications of dermatologists correlated with numbers of inflammatory eruptions (papules plus pustules), but did not with numbers of comedones. The appropriate divisions of inflammatory eruptions of half of the face to decide classifications were: 0–5, “mild”; 6–20, “moderate”; 21–50, “severe”; and more than 50, “very severe”.

Background Retinoids and active vitamin D₃ analogues regulate the proliferation and differentiation of keratinocytes and are effective in the treatment of psoriasis. Retinoids are known to be effective against acne vulgaris through comedolysis. However, the comedolytic effect of active vitamin D₃ analogues has not been reported. Objectives To investigate whether maxacalcitol, one of the active vitamin D₃ analogues, has a comedolytic effect by using spontaneously comedogenic rhino mice. Methods Rhino mice were treated topically with tretinoin and maxacalcitol once daily for 2 and 4 weeks, respectively. The dermal side of the epidermal sheet was observed to determine the size of the utricle. Haematoxylin and eosin-stained vertical sections were used to measure utricle diameter and density and to evaluate histological changes. Results Maxacalcitol (25 μg g⁻¹) and tretinoin (0·1%) significantly decreased the size and the diameter of the utricle after 1 week of treatment. However, maxacalcitol did not affect the density while tretinoin did have an effect. Histopathologically, maxacalcitol and tretinoin markedly induced epidermal hyperplasia accompanied by a minor accumulation of inflammatory cells in the dermis, with and without hypercornification, respectively. Conclusions These results indicate that maxacalcitol has a prominent effect on comedolysis and that its mechanism of action may be different from that of retinoids.