Acne and rosacea — two of the most widespread dermatological conditions — can share common features, and accurate diagnosis is especially important because antibiotic resistance is a growing concern worldwide, according to Dr. Hilary Baldwin, associate professor of dermatology at the State University of New York-Brooklyn, in a recent article in the medical journal Cutis.
The two disorders may be especially confused when the term "acne rosacea" is used, Dr. Baldwin said. She noted that the phrase was once frequently used to describe what is now known as subtype 2 (papulopustular) rosacea, which may include bumps and pimples that appear similar to acne. However, the distinction between the two prevalent disorders is important to make, she said, because the recent increase in knowledge of their very different mechanisms of action allows better understanding of appropriate therapy, particularly where antibiotics are concerned.
Dr. Baldwin noted that while acne and rosacea are clinically and biochemically different, the distinction between the two conditions is often based on a compilation of several broad generalities rather than clear-cut diagnostic criteria. For example, rosacea is a chronic disorder that occurs primarily in the central portion of the face and usually includes redness, flushing and blushing, and bumps (papules) and pimples (pustules). Rosacea can also involve the eyes and even a bulbous nose. Acne is seen most commonly in teens, while rosacea occurs most often much later. Also, unlike in patients with rosacea, blackheads are generally present, and bumps and pimples on the trunk and arms are common, she said.
Though both conditions may involve bumps and pimples, the causes and biochemical processes are different for each. Acne is a product of many factors, involving the hair follicles, hormonal stimulation of oil gland cells and bacteria that can be treated with antibiotics. On the other hand, recent research has found that rosacea appears to be linked to a dysfunction of the body's natural immune system, and should thus be treated with medications designed for their anti-inflammatory rather than antibacterial effects.
Antibiotic resistance may occur through unnecessary use of antibiotics, allowing disease-causing bacteria to evolve that are able to survive exposure to these medications, thus leading to infections that are difficult to treat. The U.S. Centers for Disease Control and Prevention (CDC) has called antibiotic resistance one of the world's most pressing public health threats, she said.
"Therefore, distinguishing between the two conditions is of great importance as we attempt to improve the health of our patients while minimizing ecologic mischief," Dr. Baldwin said, noting that anti-inflammatory therapy specifically for rosacea is now available in both oral and topical forms to help minimize the risk of bacterial resistance. "The time to be cavalier has passed."