Transient receptor potential vanilloid type 1 (TRPV1) is found on sensory neurons, keratinocytes, sebocytes, and dendritic cells. Activated TRPV1 channels are believed to help propagate the itch sensation. Therefore, there has been great interest in targeting TRPV1 to treat pruritus. Since oral formulations aimed at TRPV1 have led to adverse effects such as hyperthermia, there has been emphasis on developing novel topical agents. Several companies are investigating topical TRPV1 anti-pruritic compounds and the initial data has been very promising. These drugs have the potential to be important treatment options for the management of itch. This paper reviews topical products in current development for pruritus that target TRPV1 channels.

Acrokeratoelastoidosis (AKE) is a rare, benign papular keratoderma that presents as keratotic papules on the lateral margins of the palms and soles. It is most commonly inherited in an autosomal dominant fashion, although sporadic cases are also described. We present a sporadic case of AKE in an 11-year-old girl with a past medical history significant for asthma. On literature review, we found three other cases presenting in children with a past medical history of asthma. We suggest a possible association between asthma and sporadic cases of AKE in children. Current understanding of the pathophysiology of AKE and its associated risk factors is limited and no effective treatment exists. Awareness of a possible association with asthma and atopy, careful history recording in young patients presenting with sporadic cases of AKE, and further research may help to delineate the likelihood of an association between AKE and asthma or atopy. Developing a better understanding of the associated factors that may contribute to the disease process may help guide more effective, targeted treatments in the future.

Cutaneous non-tuberculous mycobacterial (NTM) infections have rapidly increased in incidence in recent years. Currently there is no standard treatment and the variable and nonspecific ways in which cutaneous NTM infection presents makes it a therapeutic and diagnostic challenge. We describe a 67-year-old immunocompetent woman with cutaneous NTM infection after she recently underwent a root canal procedure. Although the species was not identified and she was unable to tolerate multiple antibiotics, she ultimately responded well to three months of treatment with linezolid. Given that cutaneous NTM infection can present in immunocompetent patients and that the incidence is rising, it is important for clinicians to maintain a high index of clinical suspicion, especially in patients with a recent history of surgery, trauma, or cosmetic procedures. Linezolid has coverage against non-tuberculous mycobacteria and is an effective therapeutic option for cutaneous NTM cases in which identification to the species level is not possible or when adverse effects limit therapeutic options.

Hydroxyurea is a chemotherapeutic agent that is used in the treatment of various hematological diseases including chronic myelogenous leukemia, polycythemia vera, and sickle cell anemia. Hydroxyurea is also used to treat psoriasis. Drug-induced hyperpigmentation is a known cutaneous side effect of hydroxyurea along with xerosis, dermal ulcers, and dermatomyositis-like eruptions. Hyperpigmentation has been observed in the oral mucosa, nails, and in a generalized or a diffuse pattern. The mechanism of hyperpigmentation related to hydroxyurea is believed to be correlated with increased melanin. Classically, clinical types of diffuse hyperpigmentation owing to iron deposition in the dermis have been associated with minocycline and not with hydroxyurea. We report a novel case in which hydroxyurea hyperpigmentation is associated with iron deposition.