This study did not address rosacea, and PDT may not be suitable for all rosacea sufferers, so please do your research. Check out be careful with Levulan (aminolevulinic acid) for some group feedback.
Topical photodynamic therapy for treatment of facial erythema with acne
vulgaris, Eun Ju Hwang, MD, Modelo Clinic, Seoul, South Korea; Kyle Seo, MD, PhD, Modelo Clinic, Seoul, South Korea.
Background: PDT involves the application of a photosensitizing chemical which, when exposed to various lights, results in excitation of the photosensitizer and consequent production of a reactive oxygen species that leads to cytotoxicity. Although it is already being widely used for acne and epidermal cancers in practice, the treatment effects are not established for facial erythema including seboherric dermatitis, rosacea with acne vulgaris.
Objectives: Our study was designed to determine the effect for the treatment of facial erythema with seboherric dermatitis, rosacea.
Methods: Ten volunteers with moderate to severe facial erythema had been treated with the ALA (Levulan, DUSA, Wilmington, Mass) all over the face. An occlusive dressing followed all treatments. Two hours after ALA application, the face was irradiated for 40 ms with a fixed dose of 9 J/cm2 and 650-950 nm wavelength of IPL (Ellipse, DDD, Denmark). The effects were evaluated by clinical and chromometric examinations, H&E, Tunel staining.
Results: Rapid erythema improvements were seen in all facial erythema with variable causes including seboherric dermatitis, rosacea. In addition, acne counts were decreased significantly. More intense erythema was noted within 3 days especially in patients with erythema as opposed to those without it. In H&E and Tunel staining, there were epidermal necrosis and regeneration. Sebaceous gland were also degenerated after PDT.
Conclusion: This study demonstrated that ALA-PDT showed an excellent efficacy for the treatment of facial erythema with variable causes. These data supported the hypothesis that destruction of vessels and anti-inflammatory actions in ALA-PDT seem to cause improvement of facial erythema.
Commercial support: None identified.
Poster Abstract P3113, American Academy of Dermatology, 65th Annual Meeting February 2-6, 2007, Washington, DC. Published in Journal of the American Academy of Dermatology Volume 56, Number 2.
Further Reading:
Some more speculation about how rosacea might be linked in some way to demodex mites. So far there is no causative link – that is scientists cannot yet prove that demodex mites cause rosacea. The quest continues to find if there is a good provable link between the mites and rosacea. I remain sceptical until some good research is published.
Electron microscopic investigation into the possible etiology of rosacea and the implication for treatment, Richard Burroughs, MD, National Capital Consortium (Walter Reed Army Medical Center), Washington, DC, United States; Kurt Maggio, MD, Walter Reed Army Medical Center, Washington, DC, United States.
The presence of Demodex folliculorum has been implicated in the pathogenesis of rosacea, but never proven to be a causative agent. Most individuals in the general population have Demodex folliculorum present in their skin, yet only a fraction of the normal population develops rosacea.We hypothesize that cutaneous changes of rosacea are caused by an inflammatory response to intracellular bacteria within Demodex folliculorum. Candidate intracellular organisms include Wolbachia, other Rickettsia-like bacteria, g-proteobacteria, cytophaga-flavobacterium-bacteroides bacteria, and spiroplasmas.
Our poster depicts the first known complete electron microscopic cross-section of Demodex folliculorum. This mite was obtained from sebum expressed from the face of a patient with rosacea, then imaged with electronmicroscopy. Perfect for presentation, the poster is comprised of 24 separate electron micrographs which are pieced together digitally to depict the entire mite and its contents.
Inside Demodex there are several structures which have sizes consistent with intracellular bacteria and fungi for which we will perform PCR testing next summer. We presently have a grant from the National Rosacea Society for PCR and this poster depicts our preliminary microscopic investigation.
This poster will be the first publication of our preliminary results. Our aim is to accurately identify the intracellular organism that may be responsible for Rosacea and thereby improve medical treatment for this disease. The intracellular bacteria we are investigating are uniformly sensitive to tetracyclines. This might clarify rosacea’s favorable response to tetracycline.
Could the effects of antibiotics in rosacea be caused by their actions on intracellular bacteria of Demodex, rather than to a postulated anti-inflammatory mechanism? We believe so, and will demonstrate this in a first-of-its-kind poster.
Poster Abstract P516, American Academy of Dermatology, 65th Annual Meeting February 2-6, 2007, Washington, DC. Published in Journal of the American Academy of Dermatology Volume 56, Number 2.
Commercial support: None identified.
Also see the 2004 Press Release from the NRS titled New Study Shows Role for Bacteria in Development of Rosacea Symptoms.
In the National Rosacea Society-funded study, Dr. Kevin Kavanagh and colleagues at the National University of Ireland-Maynooth found that the bacterium Bacillus oleronius stimulated an immune system response, inducing high levels of T-cell proliferation, in 79 percent of patients with subtype 2 rosacea, compared with only 29 percent of patients without the disorder. T-cell proliferation induces an inflammatory response, evident as papules and pustules.
…
Dr. Kavanagh noted that the potential role for bacteria in causing papulopustular rosacea is supported by the fact that typical treatment for rosacea initially includes oral antibiotics that destroy B. oleronius. Interestingly, he said, antibiotics that are not harmful to these bacteria generally are not effective in the management of rosacea.
Moreover, the possibility that antigens may play a role in disease processes has been demonstrated in other disorders. For example, antigens produced by Streptococcus and Staphylococcus bacteria have been linked with such disorders as psoriasis, food poisoning and toxic shock syndrome.
Dr. Kavanagh and his colleagues are now developing antibodies against the antigen produced by B. oleronius to confirm its presence on the faces of patients with papulopustular rosacea and to define its relationship with Demodex mites.
See also Demodex Mite Bacteria causes Rosacea Inflammation ?
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