Mixed histiocytosis: A case report and published work review

Area of Science:

• Dermatology
• Pathology
• Oncology

Background:

• Histiocytoses comprise Langerhans cell histiocytosis (LCH) and non-Langerhans cell histiocytosis (NLCH).
• Cutaneous plane xanthoma (CPX) is an NLCH presenting as yellow-orange plaques, often linked to systemic conditions.
• Eosinophilic granuloma (EG) is an LCH primarily affecting bone in children.

Observation:

• A case of EG in an adult Chinese male with concurrent CPX on the scalp and face is presented.
• This represents an exceptional instance of mixed histiocytosis, combining LCH and NLCH in one patient.
• Review of existing literature on comorbid EG and NLCH cases was conducted.

Findings:

• The patient exhibited both EG and CPX, a rare mixed histiocytosis.
• This case is the first reported instance of mixed histiocytosis involving CPX and EG in China.
• The review identified limited published cases of EG co-occurring with NLCH.

Implications:

• This case expands the understanding of histiocytic disorder presentations.
• It underscores the importance of considering diverse histiocytic involvements in clinical diagnosis.
• Further research into the mechanisms and management of mixed histiocytoses is warranted.