Pityriasis Lichenoides in Thai Children: A 10-Years Review of Clinical and Treatment Outcome
Nootchanard Rujimethapass¹, Wanida Limpongsanurak¹, Srisupalak Singalavanija¹
Affiliation : ¹ Department of Pediatric Dermatology, Queen Sirikit National Institute of Child Health, Bangkok, Thailand
Background: Pityriasis lichenoides (PL) represents a unique group of inflammatory dermatologic conditions. Distinct skin manifestations typically lead to diagnosis, which is confirmed through histopathology in most cases. Treatment for this group of conditions varies. Disease progression is chronic in most cases, though it is generally benign.
Objective: To investigate epidemiology, clinical subtypes, treatment, and disease progression of PL in children.
Materials and Methods: A retrospective data collection from the medical records of patients diagnosed with PL at the National Children’s Health Institute during a ten-year period, between January 1, 2012, and December 31, 2022, was accomplished.
Results: In the present study, there were 43 patients, and the male-to-female ratio was 1.3:1. The most common age groups at onset of PL was 4 to 7 years old. Ten cases (23.3%) of pityriasis lichenoides et varioliformis acuta (PLEVA) and 33 cases (76.7%) of pityriasis lichenoides chronica (PLC) were identified. All cases were confirmed by skin biopsy. There were two cases of febrile ulceronecrotic Mucha-Habermann disease (FUMHD). Systemic treatment included erythromycin in 95.3%, prednisolone in 9.3%, and methotrexate in 9.3%. The duration of illness of PLC ranged from 2 to 54 months, with an average of 7±4 months, whereas in PLEVA’s disease duration ranged from 1 to 20 months, with an average of 4±2 months (p<0.05). Dyspigmentation was predominantly observed in PLC, whereas varioliform scarring was more common in PLEVA (p<0.05). Among all patients diagnosed with PL, one patient (2.3%) developed mycosis fungoides as cutaneous T-cell lymphoma, during follow-up.
Conclusion: PL is typically a benign and chronic condition, though it may be life-threatening in rare cases. Diagnosis is primarily based on clinical presentation and histopathological examination of skin biopsies, although it can be challenging and subject to delays. Prognosis is generally favorable; however, ongoing monitoring is essential.
Received 22 January 2025 | Revised 25 March 2025 | Accepted 28 April 2025
DOI: 10.35755/jmedassocthai.2025.5.377-383-02606
Keywords : Pityriasis lichenoides; Pityriasis lichenoides et varioliformis acuta (PLEVA); Pityriasis lichenoides chronica (PLC); Febrile ulceronecrotic Mucha-Habermann disease (FUMHD)
