The proportion of ACD caused by lidocaine is higher than expected. This is likely secondary to an increase in OTC medicaments containing lidocaine. Patients who are patch test-positive to a local anesthetic should be challenged intradermally to confirm clinical relevance. Because ACD is a delayed Type IV hypersensitivity reaction (localized dermatitis), the risk of anaphylaxis is not a concern.

Chronic bacterial lung infections in cystic fibrosis (CF) are the leading cause of morbidity and mortality. While a range of bacteria are known to be capable of establishing residence in the CF lung, only a small number have a clearly established link to deteriorating clinical status. The two bacteria with the clearest roles in CF lung disease are Pseudomonas aeruginosa and bacteria belonging to the Burkholderia cepacia complex (BCC). A number of common adaptations by P. aeruginosa strains to chronic lung infection in CF have been well described. Typically, initial isolates of P. aeruginosa are nonmucoid and display a range of putative virulence determinants. Upon establishment of chronic infection, subsequent isolates ultimately show a reduction in putative virulence determinants, including swimming motility, along with an acquisition of the mucoid phenotype and increased levels of antimicrobial resistance. Infections by BCC are marked by an unpredictable, but typically worse, clinical outcome. However, in contrast to P. aeruginosa infections in CF, studies describing adaptive changes in BCC bacterial phenotype during chronic lung infections are far more limited. To further enhance our understanding of chronic lung infections by BCC bacteria in CF, we assessed the swimming motility phenotype in 551 isolates of BCC bacteria from cystic fibrosis (CF) lung infections between 1981 and 2007. These data suggest that swimming motility is not typically lost by BCC during chronic infection, unlike as seen in P. aeruginosa infections. Furthermore, while we observed a statistically significant link between mucoidy and motility, we did not detect any link between motility phenotype and clinical outcome. These studies highlight the need for further work to understand the adaptive changes of BCC bacteria during chronic infection in the CF lung.

The aetiology and clinical course of FFA remain to be established. Unfortunately, despite the numerous treatment options available, no one therapeutic regimen has proven effective in stopping recession of the hairline and inducing hair growth.

Polyarteritis nodosa (PAN) is a rare vasculitis affecting medium-sized vessels. Cutaneous PAN is a clinical variant, and we report the first case of empagliflozin-induced cutaneous PAN in a 69-year-old man. After starting empagliflozin, the patient presented with tender subcutaneous nodules on his legs, which showed a medium-sized vessel vasculitis on histopathology. Upon cessation of this medication, he had full resolution of these nodules. This case illustrates that empagliflozin can induce cutaneous PAN, and further attention to this medication's association with cutaneous PAN is warranted.

We present a patient with atypical pyoderma gangrenosum (APG), which involved the patient's arm and hand. Hemorrhagic bullae and progressive ulcerations were initially thought to be secondary to an infectious process, but a biopsy revealed PG. Awareness of APG by infectious disease services may prevent unnecessary use of broad-spectrum antibiotics.