Thai Journal of Dermatology

Hydroxyurea Induced Dermatomyositis-Like Eruption and Melanonychia

Worakamol Tharnkratoke, Nataya Voravutinon — Thu, 06 Nov 2025 00:00:00 +0700

Hydroxyurea is utilized to treat myeloproliferative disorders, including essential thrombocythemia, polycythemia vera, and chronic myeloid leukemia. The most common adverse effects are hematological issues, gastrointestinal symptoms, and anorexia, while dermatological side effects are rare. We present a patient who developed a dermatomyositis-like eruption and melanonychia, induced by hydroxyurea, after receiving the drug for the treatment of essential thrombocytosis.

Concurrent manifestations of primary extramammary Paget’s disease involving the left axilla and the left groin with nodal and bone metastasis

Thitipat Yooyuenyong, Anakaporn Tiyawatanaroj — Thu, 06 Nov 2025 00:00:00 +0700

Primary extramammary Paget's disease (EMPD) is a rare type of skin cancer, as a less aggressive intraepithelial adenocarcinoma. Patients usually present with skin lesions at apocrine gland sites such as the vulva, penoscrotal area, perianal area, umbilical area, and, less commonly, the axilla. EMPD is primarily an intraepidermal neoplasm but has the potential to invade deeper structures and metastasis. This case report presented a patient diagnosed with concurrent sites of primary EMPD, with one site showing nodal and bone metastasis. Making an accurate diagnosis of EMPD can be challenging as case occurrences are rare.

Ribociclib-induced Vitiligo in Advanced Stage Breast Cancer: Two Case Reports

Pemika Panathara, Sinee Weschawalit — Thu, 06 Nov 2025 00:00:00 +0700

Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors, including ribociclib, have markedly improved therapeutic outcomes for patients with hormone receptor-positive advanced breast cancer. While generally well-tolerated, these agents can cause various adverse effects, some of which are infrequent and may be underrecognized. Vitiligo is a rare but potentially distressing cutaneous side effect of CDK4/6 inhibitors. We present two cases of vitiligo occurring in patients receiving ribociclib therapy for advanced breast cancer. The first case involves a 68-year-old woman who developed depigmented macules on her face and extremities after 22 months of treatment. Ribociclib was discontinued due to disease progression, but the depigmented lesions worsen. The second case features a 55-year-old woman who developed similar lesions six months after beginning ribociclib therapy.

Vasculonecrotic Erythema Nodosum Leprosum in a Case of Lepromatous Leprosy: A Rare and Severe Presentation

Varisa Ramkul, Phatcharawat Chirasuthat — Thu, 06 Nov 2025 00:00:00 +0700

Lepromatous leprosy, caused by Mycobacterium leprae or Mycobacterium lepromatosis, is a progressive, multi-systemic infection affecting the skin and peripheral nerves. Erythema nodosum leprosum (ENL) is a severe immunological complication in lepromatous and borderline leprosy, presenting with inflamed skin nodules. Vasculonecrotic ENL, a rare form, involves deep ulcerations, necrosis, and systemic effects. We report a 40-year-old Myanmarese male with multibacillary leprosy presenting with erythematous patches, nodules, and vesiculopustular bullous eruptions on the trunk and extremities, with bilateral median nerve enlargement and sensory loss. Histopathology confirmed lepromatous leprosy with necrotizing vasculitis and neutrophil infiltration, leading to a diagnosis of vasculonecrotic ENL. Despite initial improvement with multidrug therapy and oral corticosteroids, the patient experienced a relapse of bullous lesions and neuritis following prednisolone tapering. Treatment was intensified with high-dose corticosteroids, leading to the resolution of his bullous lesions.

Bullous Erysipeloid: An Atypical Manifestation in an Immunocompromised Patient – A Case Report

Shutisara Wongwenai, Teerapong Rattananukrom — Thu, 06 Nov 2025 00:00:00 +0700

Erysipeloid is a rare infection caused by Erysipelothrix rhusiopathiae. We report the case of a 58-year-old woman with HIV and spondylarthritis on immunosuppressants, who had a history of direct contact fish and shrimp, who presented with a progressive, painful plaque with central bullae on her left index finger. At her initial visit, she was diagnosed with bullous cellulitis and was treated with oral clindamycin (300 mg three times daily) and intravenous levofloxacin 750 mg once daily. Despite treatment, her condition worsened, necessitating hospitalization and surgical debridement. Microbiological culture from skin lesion confirmed the presence of Erysipelothrix rhusiopathiae, leading to the diagnosis of erysipeloid. Following a 14-day course of penicillin V, the patient showed significant clinical improvement. Atypical presentations of erysipeloid, as bullous lesions, can occur, particularly in immunocompromised host.