Over the course of your career, how has your understanding of conditions such as acne and rosacea changed?
“The understanding of acne pathophysiology has come a long way,” says Dr. Baldwin. “We used to believe that acne was an infectious disorder. P. acnes was considered an innocent bystander that caused problems only because it was given food (sebum) and deprived of oxygen, which it preferred. Now we are beginning to recognize that acne is an inflammatory disorder from start to finish and that P. acnes plays a role not because it is causing an infection but because it is causing/worsening an inflammatory condition by releasing pro-inflammatory cytokines,” she observes. “The reason why one person has acne and another does not is probably due to the reaction of the individual’s immune system to the presence of P. acnes in the follicle—the more the immune system overreacts to this commensal organism, the more likely acne is to occur. This underscores the ultimate futility of using antibiotics to treat acne.
P acnes is a commensal organism that cannot be eradicated, so if antibiotics are functioning by decreasing P. acnes counts, it is only temporary. Antibiotics are likely working mostly due to their anti-inflammatory characteristics. So treatment options now are looking more at anti-inflammatory doses of doxycycline and continuing the use of retinoids and BP in order to treat the disease while being good stewards of antibiotics. The entire concept of antibiotic resistance and the role that dermatologists play in the problem has occurred during my journey.”
Similar advancements have been made in the arena of rosacea, “Little was understood about the pathophysiology of rosacea when I began my career in dermatology. So everything that we now recognize is new. We now believe that rosacea is a chronic inflammatory disease with neurovascular dysregulation, probably caused by an innate immune dysfunction. Although it has been known for years that antibiotics of the tetracycline class work in the treatment of rosacea, it is now clear that their efficacy is due to their anti-inflammatory capabilities rather than their antibiotic activities. It is now considered by most to be inappropriate to use antibiotic-dose tetracyclines to treat this inflammatory disorder. Most recently we have seen the introduction of topical ivermectin which is highly effective in treating rosacea,” says Dr. Baldwin.
Are there any new treatments or procedures in the pipeline that you are looking forward to?
“In acne, it is interesting that 34 years after the launch of isotretinoin, we are still not sure why most patients who receive a full course remain disease-free. We know why it works, but not why the results last,” Dr. Baldwin observes. “Diane Thiboutot’s and Jenny Kim’s labs are working on finding out the answer to this problem. The answer may well point us in other directions for therapeutic options. Laser and light hold promise for methods of destroying or damaging the sebaceous glands that might render effective treatment or even a cure by depriving the P. acnes of food and thereby stopping the inflammatory cascade.” She also notes that laser and light therapy for acne or rosacea removes the adherence problem.
In terms of the future, topical antiandrogens “could be effective and safe treatment for both acne and greasy skin complaints,” says Dr. Baldwin. “Acne may be treated in the future by the application of bacteria (topical probiotics) to the skin to repopulate the follicle with good bacteria to outcompete the acne-causing P. acnes.”
Do you have any advice for how physicians can make an impression and communicate with patients with acne and/or rosacea?
“Both conditions are chronic disorders which necessitate on-going therapy. It is important to recognize and to communicate that treatment should be divided into acute and chronic therapy,” says Dr. Baldwin. “Acute to ‘get them over the hurdle’ and chronic to ‘stay the course.’ These treatments plans may be considerably different. In both conditions, the goal is to curtail the use of antibiotics and to avoid altogether if possible even though they may cause initial rapid and impressive results,” she says. “Certainly in both conditions, ‘exit strategies’ must be considered if/when antibiotics are used so that discontinuation can be as early as possible and maintenance of improvement as effective and long-lasting as possible. Adherence, therefore, with non-antibiotic approaches is paramount for the safety of the patient, those around them and society as a whole.” According to Dr. Baldwin, “Antibiotic resistance is becoming the most crucial public health crisis that we are likely to ever face and its dangers cannot be overstressed.”