Wednesday, March 28, 2007

pathogen infection (Chlamydia pneumoniae) cause theory

A really interesting thread is going on in the rosacea-support group. Dan is airing some of his thoughts on how a pathogen might lead to the chronic inflammation we see in rosacea. Even though Dan clearly states he has no medical background (and indeed it is worth remembering this point) it is clear that he has done a lot of reading on this topic.

Some more thoughts on a possible link: Chlamydia pneumoniae and Rosacea: A potential link?

Chlamydia pneumoniae may be something new to many (it was to me), so also see the wikipedia page: Chlamydophila pneumoniae

lavender, arnica, aloe vera, tea tree oil, and calendula ; do they work ?

Australia's Choice magazine is an independent magazine that reviews products from the point of view of the consumer. Recently they published an articled titled `Natural first aid: Are natural first-aid remedies effective?'

The summary of the article ;

There’s plenty of anecdotal evidence from years of traditional use, but scientific evidence for the clinical effectiveness of natural first-aid remedies is generally lacking.

Most of the world relies mainly on natural medicines, and their popularity is growing in the west. You can easily find natural first-aid remedies in pharmacies and healthfood shops. But can you be sure that they’ll work?

Something I hadn't heard of before is a body called `Commision E'. Where available the article cites findings from Commission E.

Commission E

An exception to the lack of scientific study of natural remedies is Commission E, a German government regulatory agency composed of scientists, pharmacists, toxicologists, physicians and herbalists that has produced a series of documents known as herbal monographs — essentially formal reviews of medicinal herbs based on the available scientific evidence as well as evidence from traditional use, case studies and the experience of modern herbalists. The monographs are considered to provide authoritative information including approved uses of the herbs and their side effects, interactions and doses.

See the full article for examples of where Commission E has published relevant information.

Some of the remedies in this article have been discussed in the past as possible treatments for rosacea. Unfortunately there isn't much in this well written article suggesting that any of these natural remedies have been proven as effective for inflammatory skin diseases. 

Following are some interesting extracts ; 

Aloe Vera

The evidence is mixed, but it probably can’t hurt to try certified aloe vera gel (or aloe vera juice squeezed directly from the plant, if you have one) on minor wounds and burns/sunburn — and it might work.

Arnica

Arnica montana is a medicinal herb with a long history of use for treating swelling and bruising resulting from blows, and injuries such as sprains. Arnica flower is commonly available in both herbal and homeopathic preparations.

Clinical evidence for arnica as an effective first aid treatment is lacking, but people with osteoarthritis might want to give it a go.

Calendula

Calendula officinalis, or marigold, is a member of the daisy family (Compositae/Asteraceae). Its preparations have been used since ancient times to treat inflammatory skin conditions and accelerate wound healing.

Lavender oil

Oil from the lavender flower (Lavandula angustifolia) has been used as an antiseptic in medicine since ancient Arabian, Greek and Roman times.

The clinical evidence for its effectiveness as an antiseptic is lacking, though sprinkling lavender oil in your bathwater to help you relax is likely to be safe enough.

Tea tree oil

Australian Aborigines have used the leaves of the Melaleuca alternifolia plant for medicinal purposes for many centuries. Tea tree oil’s traditional use is as an antiseptic for preventing and treating minor skin infections.

The evidence so far is encouraging, though not definitive. It may be worth a try on insect bites and minor skin infections.

Further Reading ;

so just how does metrogel work ?

I have mentioned a few times in the past that the way that metrogel helps rosacea is unknown. This statement deserves some clarification. Actually the way that metronidazole works is well known. How the effect of metrogel leads to a benefit in rosacea, well, that is something worth exploring some more later on.

You may wonder why there is so much emphasis on the metronidazole based products ? As much as metrogel and its friends metrocream, metrolotion, rozex, noritate (and indeed generic metrogel, also from fougera) are not a panacea for rosacea, they do represent the single most proven treatment specifically for rosacea. Thus newly diagnosed rosacea sufferers are quite likely to leave their doctor's surgery with a script for metro-something. All the studies show that in many cases metrogel does indeed work. Further, other studies clearly show that combining metrogel with antibiotics results in better clearance.

So back to `how does it work ?'  Well my one sentence summary is "metronidazole breaks down into a substance that kills the DNA of the cells of some particular bacteria and protozoa".

Thanks to Dan for sending me the following links ;

From DrugBank: Metronidazole

Pharmacology: Metronidazole, a synthetic antibacterial and antiprotozoal agent of the nitroimidazole class, is used against protozoa such as Trichomonas vaginalis, amebiasis, and giardiasis. Metronidazole is extremely effective against anaerobic bacterial infections and is also used to treat Crohn's disease, antibiotic-associated diarrhea, and rosacea.

Mechanism of Action: Unionized metronidazole is selective for anaerobic bacteria due to their ability to intracellularly reduce metronidazole to its active form. This reduced metronidazole then disrupts DNA's helical structure, inhibiting bacterial nucleic acid synthesis and resulting in bacterial cell death.

From Antibiotics that Inhibit Nucleic Acid Synthesis

Figure 11-8. Structure of metronidazole and its mechanism of action. Metronidazole enters an aerobic bacterium where, via the electron transport protein ferrodoxin, it is reduced. The drug then binds to DNA, and DNA breakage occurs.

(An anaerobic organism is any organism that does not require oxygen for growth. Protozoa are a particular type of single cell organisms.)

This naturally leads to the followup question - if eliminating the substances that metronidazole (and for the purposes of this argument, lets include systemic antibiotics as well) is active against leads to relief from some rosacea symptoms, what does that say about the possible cause of rosacea ? Now, that is a question that there isn't much agreement about and something worth talking about some more, later.

Further Reading ;

ocular demodex, tea tree oil as a treatment

This recently published paper suggests that a variety of ocular symptoms might be caused by demodex infestation. Six patients all having demodex present, and suffering with recalcitrant symptoms (including 4 diagnosed with rosacea) were given tea tree oil for a weekly eyelid scrub and tea tree shampoo for a daily scrub. All patients showed a large decrease in demodex counts and relief from their symptoms.

Other recently published studies are showing that tea tree oil kills demodex. See ;

I have always pushed the line that demodex mites have thus far only been proven to be innocent bystanders in rosacea symptoms. In order to prove that the mites are responsible for some ocular symptoms we now need double blind studies to show 2 things - firstly that killing demodex does lead to a reduction in ocular rosacea symptoms and secondly some studies that show how tea tree oil works. We also now need larger studies that confirm that tea tree oil is a safe therapy for ocular symptoms.

Corneal Manifestations of Ocular Demodex Infestation, Kheirkhah A, Casas V, Li W, Raju VK, Tseng SC., Ocular Surface Center, Miami, Florida. Am J Ophthalmol. 2007 Mar 19

PURPOSE: To report the corneal manifestations in eyes with Demodex infestation of the eyelids.

DESIGN: Noncomparative, interventional case series.

METHODS: This retrospective review included six patients with Demodex blepharitis who also exhibited corneal abnormalities, which led to suspicion of limbal stem cell deficiency in three cases. All patients received weekly lid scrubs with 50% tea tree oil and a daily lid scrubs with tea tree shampoo for a minimum of six weeks. Improvement of symptoms and corneal and conjunctival signs were evaluated.

RESULTS: All six patients exhibited ocular irritation and conjunctival inflammation, while meibomian gland dysfunction (n = 5), rosacea (n = 4), and decreased vision (n = 3) also were noted despite prior treatments with oral tetracycline, topical steroids with antibiotics, and lid scrub with baby shampoo. These patients were proven to have Demodex folliculorum (n = 6) and Demodex brevis (n = 3) by microscopic examination of epilated lashes. Their corneal manifestation included superficial corneal vascularization (six eyes of five cases), marginal corneal infiltration (two eyes of two cases), phlyctenule-like lesion (one eye of one case), superficial corneal opacity (two eyes of two cases), and nodular corneal scar (two eyes of two cases). After treatment, the Demodex count was reduced from 6.8 +/- 2.8 to 1 +/- 0.9 (standard deviation; P = .001). All patients showed dramatic resolution of ocular irritation, conjunctival inflammation, and all inflammatory, but not scarred, corneal signs; three patients showed improved vision.

CONCLUSIONS: A variety of corneal pathologic features together with conjunctival inflammation, commonly noted in rosacea, can be found in patients with Demodex infestation of the eyelids. When conventional treatments for rosacea fail, one may consider lid scrub with tea tree oil to eradicate mites as a new treatment.

Further Reading ;

Friday, March 02, 2007

Rosacea News February 2007

Rosacea News February 2007





1. demodex bacteria - could that be the cause ?





PAPER: Electron microscopic investigation into the possible etiology of


rosacea and the implication for treatment,





http://rosacea.ii.net/news/2007/02/demodex-bacteria-could-that-be-cause.html





2. red face and photodynamic therapy (PDT)





PAPER: Topical photodynamic therapy for treatment of facial erythema


with acne vulgaris





http://rosacea.ii.net/news/2007/02/red-face-and-photodynamic-therapy-pdt.html





3. topical antihistamine reduces oily skin and acne





PAPER: A 4-week, randomized, double-blind, parallel group trial


evaluating the efficacy and tolerability of sebum control product in


male and female subjects with oily skin appearance and mild to moderate


acne vulgaris





http://rosacea.ii.net/news/2007/02/topical-antihistamine-reduces-oily-skin.html





4. revlon (Almay) sensitive skin cream helps rosacea





PAPER: Use of a liquid cream improves sensitive rosacea-prone skin





http://rosacea.ii.net/news/2007/02/revlon-almay-sensitive-skin-cream-helps.html





5. Mariah Carey has rosacea ? celebrities as advocates ?





MAGAZINE: I’ve got thighs and buttocks, I'm never going to be a size zero





http://rosacea.ii.net/news/2007/02/mariah-carey-has-rosacea-celebrities-as.html





6. rambazole dose and side effects being studied





PAPER: Tolerability, safety, and pharmacokinetics of single and


multiple oral dosages of R115866 in healthy volunteers





http://rosacea.ii.net/news/2007/02/rambazole-dose-and-side-effects-being.html





7. cleansing your SD skin with a sonic brush (Clarisonic)





PAPER: An efficacy assessment of a novel skin cleansing device in


seborrheic dermatitis,





http://rosacea.ii.net/news/2007/02/cleansing-your-sd-skin-with-sonic-brush.html
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