A remarkable increase in the prevalence of cutaneous nontuberculous mycobacterial (NTM) infection has occurred worldwide. However, updated data regarding cutaneous NTM infection in Thailand is limited. This study aim to describe the clinical manifestations, pathogenic organism, and prognostic factors of cutaneous NTM infections among patients living in Thailand. The electronic medical records of all patients with confirmatory diagnosis of cutaneous NTM infection from either positive cultures or polymerase chain reaction were retrospectively reviewed at a university-based hospital. From 2011 to 2017, a total of 88 patients with a confirmed diagnosis of cutaneous NTM infection were included. Mycobacterium abscessus was the most common pathogens followed by M haemophilum and M marinum (61.4%, 10.2%, and 8.1%, respectively). Nodule and plaque were 2 most common lesions (26.4% and 25.5%, respectively) and lower leg is the most common site of involvement (50.9%). The majority of patients presented with single lesion (67%). Seven patients (7.9%) had history of surgical procedure and/or cosmetic injection before the development of lesion and all pathogenic organisms in this group were rapidly growing mycobacteria. Sweet's syndrome and erythema nodosum were the 2 most common reactive dermatoses, presented in 3.4% and 2.3%, respectively. The majority of patients infected with cutaneous M haemophilum infections were immunocompromised and lacked history of preceding trauma (77.8%). Patients with cutaneous NTM that receiving less than 3 medications was associated with higher disease relapse (odds ratio 65.86; P = .02). M abscessus is the most common pathogen of cutaneous NTM infection in Thailand. The prevalence of M haemophilum is increasing and should be particularly cautious in immunocompromised patients. Rapidly growing mycobacteria should be suspected in all cases of procedure-related cutaneous NTM. We recommend at least 3 antibiotics should be considered for cutaneous NTM infection to reduce the rate of relapse.

Atezolizumab is a humanized anti-PD-L1 immune checkpoint antibody that is currently used in many kinds of advanced carcinoma including metastatic non-small cell lung cancer. The cutaneous side effect profile reported only 20% of the patients which had only mild maculopapular rash that required no treatment. There is no case report of anti-PD-L1 antibody-induced Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) eruptions. To the best of our knowledge, there is no case report of atezolizumab-induced SJS or SJS/TEN induced by anti-PD-L1 immune checkpoint antibodies. We believe that our report will be useful to dermatologists who are consultants in the inpatient settings, as atezolizumab is an anti-neoplastic agent that has a potential to be used in multiple malignancies.

Follicular hyperkeratotic spicules is a rare skin disorder that is usually associated with multiple myeloma. The condition typically presents with tiny hyperkeratotic spicules in follicular distribution and predominantly on the face. To our knowledge, there has been one reported case of this condition without underlying disease. We herein report the second case of idiopathic follicular hyperkeratotic spicules in a 54-year-old Thai woman presenting with multiple follicular horn-like spicules on her face and neck.

Granular parakeratosis (GP) is a distinctive acquired keratotic dermatosis that is usually presented with brownish-red hyperkeratotic papules and plaques in the intertriginous areas. Follicular involvement in GP could be either extending lesions from interfollicular epithelium or originating primarily from the follicular epithelium. The latter was named follicular GP and is considered an extremely rare condition. To our knowledge, there has been one reported case so far in the literature. We herein report the second case of follicular GP in a 52-year-old Thai man presenting with multiple tiny filiform hyperkeratotic papules on his face 2 weeks after using anti-melasma cream. We also propose a classification of GP based on its distinct clinical manifestations and histopathological findings.

Acute inflammatory edema (AIE) is a rare variant of pseudocellulitis characterized by blanchable, erythematous, and edematous plaques mainly on the thighs and abdomen and sparing areas of increased pressure. The condition occurs predominantly in critically ill patients with hypoalbuminemia, those with increased body mass index, and those with evidence of fluid overload. AIE was introduced in 2019; however, its histopathological picture has never been elucidated in the literature. We report a case of AIE in a 64-year-old Thai woman with several comorbidities and illustrate its histopathological and immunohistochemical features for the first time. Treatment with diuretics, fluid restriction, and adjuvant hemodialysis revealed marked improvement after ten days. Our report emphasizes that AIE is a distinct dermatosis with specific characteristics that help differentiate AIE from cellulitis and other pseudocellulitic conditions. Furthermore, our observations support the role of lymphatic alterations in the pathogenesis of the disease.