Background: Laugier-Hunziker syndrome (LHS) is a rare, benign, acquired disorder that is usually characterized by hyperpigmentation of the oral cavity and lips, along with longitudinal melanonychia. Till date, its characteristics have not been investigated in a large number of patients in a single-center study. Objective: This study aimed to investigate the clinical, dermoscopic, and histological characteristics of LHS. Methods: We retrospectively reviewed the medical records, biopsy specimens, and clinical and dermoscopic photographs of 21 patients diagnosed with LHS at Pusan National University Hospital (Busan and Yangsan) over a period of 15 years (2008∼2022). Results: Among the 21 patients, 20 patients (95.2%) were female and one patient (4.8%) was male, and the mean age was 56.0 years (range: 18∼75 years). The lower lip (95.2%) was the most frequently affected oral mucosa, followed by the upper lip (81.0%), buccal mucosa (66.7%), tongue (57.1%), gingiva (42.9%), and palate (14.3%). The nails were the most commonly affected extraoral site, and in our study, eight of 21 patients (38.1%) presented with periungual lesions. Based on the dermoscopic findings, a globular pattern was the most common. Histologically, the lesions showed epithelial acanthosis and increased basal keratinocyte melanin without an increase in the number of melanocytes. Conclusion This is the first study to investigate the clinical, dermoscopic, and histological characteristics of patients with LHS. The results of this study could be helpful in understanding LHS.

Pyoderma gangrenosum (PG) is a neutrophilic dermatosis characterized by non-infectious ulceration of the skin. It is associated with various systemic diseases, including Takayasu arteritis (TA), rheumatoid arthritis, and inflammatory bowel disease. Notably, the co-occurrence of PG and TA is more frequent among Asians. Here, we present a rare case of TA associated with PG. A 42-year-old woman presented with recurrent ulcers affecting her legs, trunk, arms, and face, which had been refractory to various treatments for 7 years. Recently, the patient had experienced weakness in her left leg, dizziness, and a fever that had persisted for more than a month. Computed tomography angiography revealed thickening and irregularities in the common carotid arteries, right subclavian artery, and aortic arch. TA was diagnosed, following which treatment was initiated with systemic corticosteroids. It is important to consider TA in patients with PG, particularly in young women.

Kaposi’s varicelliform eruption (KVE) is a rare viral infection primarily caused by herpes simplex virus (HSV). This condition frequently presents concomitantly with underlying chronic skin disorders, particularly atopic dermatitis (AD). This report describes a rare case of sepsis resulting from KVE in a patient with AD. A 30-year-old male patient with a history of AD presented with painful skin lesions characterized by papulovesicular eruptions, crusts, erythema, and erosions, initially localized to the neck and spreading throughout his body, accompanied by a high fever. Laboratory findings confirmed HSV infection and sepsis. Thus, a diagnosis of KVE compounded by sepsis was established. Systemic acyclovir and antibiotics led to complete recovery within 3 weeks, with resolution of fever and skin manifestations, and general health improvement. Timely recognition and management of KVE are crucial for prevention of adverse outcomes. Both physicians and patients with AD should be made aware of the predisposing factors and risks associated with KVE.

Congenital smooth muscle hamartoma is a benign proliferation of smooth muscles within the dermis. The classic form presents as well-defined, skin-colored, or hyperpigmented plaques associated with hypertrichosis. However, there have been reports of atypical forms, including a follicular spotted appearance, linear atrophic plaques, and morphea-like forms. In such cases, distinguishing congenital smooth muscle hamartomas from other cutaneous diseases can be challenging. Herein, we report on a 16-month-old boy who presented with a hypopigmented patch and hypertrichosis on his back since birth. Histopathological examination revealed mild acanthosis and well-defined smooth muscle bundles haphazardly oriented in the dermis. These bundles stained positively with Masson’s trichrome stain. Based on these findings, a definitive diagnosis of congenital smooth muscle hamartoma was established. In conclusion, an exceptionally rare case of congenital smooth muscle hamartoma with a hypopigmented appearance is reported.

Background: Female-pattern hair loss (FPHL) is characterized by diffuse hair thinning in the mid-frontal scalp and increased hair shedding. Although the use of low-dose oral minoxidil (LDOM) is increasing significantly in Korea, data on its use are limited. Objective: To determine the efficacy and safety of LDOM in Korean patients with FPHL. Methods: This retrospective, single-center study was conducted at Pusan National University Hospital. The study included female patients with pattern hair loss who received treatment with LDOM at 1.25 mg/d for a minimum of 6 months in combination with other treatments. Patients were eligible for LDOM addition if their previous treatments showed a limited response and the previous treatment regimen remained unchanged throughout the evaluation period. Clinical response to treatment was evaluated using the Sinclair hair loss severity scale. Results: The study included 44 females with FPHL. Before treatment, the mean Sinclair scale score was 2.77, which decreased to 2.27 after treatment. By the 3rd month, one patient (2.3%) experienced worsening, while seven patients (15.9%) showed slight improvement. By the 6th month, the treatment response was as follows: stabilization in 30 patients (68.2%), slight improvement in 13 patients (29.5%), and substantial improvement in one patient (2.3%). Adverse effects, predominantly hypertrichosis, were observed in nine patients. All adverse effects improved upon discontinuation of LDOM and no life-threatening adverse effects were observed during the study. Conclusion This study provides evidence that LDOM can be an effective therapeutic option with a good safety profile for FPHL.