Antibiotic resistance in dermatology: The scope of the problem and strategies to address it.

Antibiotic resistance is a growing health concern that has attracted increasing attention from clinicians and scientists in recent years. Although resistance is an inevitable consequence of bacterial evolution and natural selection, misuse and overuse of antibiotics play a significant role in its acceleration. Antibiotics are the mainstay of therapy for common dermatoses, including acne and rosacea, as well as for skin and soft tissue infections. Therefore, it is critical for dermatologists and physicians across all disciplines to identify, appropriately manage, and prevent cases of antibiotic resistance. This review explores dermatologic conditions in which the development of antibiotic resistance is a risk and discusses mechanisms underlying the development of resistance. We discuss disease-specific strategies for overcoming resistant strains and improving antimicrobial stewardship along with recent advances in the development of novel approaches to counter antibiotic resistance.

What lies beneath: Cutaneous involvement of mantle cell lymphoma underlying an insect-bite-like reaction.

Mantle cell lymphoma (MCL) is an uncommon subtype of mature B-cell non-Hodgkin lymphoma characterized by specific morphologic, immunophenotypic, and genetic characteristics, namely the t(11;14)(q13;q32) chromosomal translocation with resultant cyclin D1 overexpression. MCL has a generally aggressive course and is often widely disseminated at the time of diagnosis. Skin involvement is exceedingly rare and is seldom the first manifestation of MCL. We present a case of MCL in an 84-year-old man with cutaneous involvement as the first manifestation, discovered incidentally after biopsy of a persistent nodule believed to be an insect bite. This case not only serves to raise awareness of the possibility of MCL presenting in the skin but also to point out that MCL can have lesions with both an insect-bite-like reaction and a deeper dermal MCL infiltrate.

Brief Update on Dermatologic Uses of Methotrexate

Methotrexate (MTX), an agent originally intended for anti-neoplastic use, has been successfully employed in the treatment of a variety of dermatologic conditions. In addition to its multiple clinical indications, variable dosing and modes of administration make it a viable option for patients of all ages and most comorbidities. MTX is a folate analog that antagonizes dihydrofolate reductase, thus inhibiting thymidylate synthesis and, ultimately, the production of pyrimidine. Depending on dosage, MTX can function as an anti-inflammatory agent, immunomodulator, or antimetabolite. Patients suffering from psoriasis have benefited from MTX in addition to those with atopic dermatitis, chronic urticaria, pemphigus vulgaris, bullous pemphigoid, cutaneous lupus erythematosus, cutaneous sarcoidosis, and mycosis fungoides. Although patients with these conditions can benefit from MTX treatment, the drug can cause adverse sequelae, including hematologic, pulmonary, gastrointestinal, and hepatic side effects. Therefore, the drug should be administered under careful physician supervision.

Shingrix for Herpes Zoster: A Review

Herpes zoster (HZ), also known as shingles, results from reactivation of the latent varicella-zoster virus (VZV), which commonly causes chickenpox in childhood. Greater than 90% of adults are infected with this virus, putting them at risk for reactivation. HZ presents as a painful, vesicular rash distributed in a unilateral and dermatomal pattern along dorsal root or cranial nerve ganglia. The rash often presents with prodromal symptoms and progresses to include clear vesicular clusters, evolving through stages of pustulation, ulceration, and crusting. HZ therapy currently involves the use of antiviral agents and pain management; however, HZ prophylaxis has been strongly recommended in older adults through vaccination with a live attenuated vaccine, Zostavax®. A new recombinant subunit vaccine, HZ/su (Shingrix®), is the subject of this review. In clinical trials, HZ/su demonstrated an overall vaccine efficacy of 97.2% among participants 50 years of age or older, indicating a significantly reduced risk of HZ in these individuals. Shingrix® was approved by the US FDA in October 2017 as HZ prophylaxis.