Perianal Crohn-like disease in infancy revealing multisystem Langerhans cell histiocytosis


Daldaban Sarıca B., Karadoğan M., Arslan R., Sayıner A., AVCI A.

BMC Pediatrics, cilt.26, sa.1, 2026 (SCI-Expanded, Scopus)

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 26 Sayı: 1
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1186/s12887-026-06907-2
  • Dergi Adı: BMC Pediatrics
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CINAHL, EMBASE, MEDLINE, Directory of Open Access Journals, Biomedical Reference Collection: Corporate Edition (EBSCO), Health Research Premium Collection (ProQuest)
  • Anahtar Kelimeler: Very early-onset inflammatory bowel disease, Perianal lesions, BRAF
  • Sağlık Bilimleri Üniversitesi Adresli: Evet

Özet

Background: Langerhans cell histiocytosis (LCH) is a rare inflammatory myeloid neoplasm characterized by abnormal myeloid differentiation and activation of the mitogen-activated protein kinase (MAPK) pathway. Since atypical dermatological or gastrointestinal manifestations in early childhood can lead to diagnostic delays, timely recognition of this potentially multisystemic disease is critical for a favorable prognosis. Case presentation: A 22-month-old male patient presented to the pediatric gastroenterology outpatient clinic with complaints of bloody-mucoid diarrhea for three months, significant weight loss, and non-healing ulcerative lesions in the perianal region. His family history included an uncle with ulcerative colitis. A preliminary diagnosis of very early-onset inflammatory bowel disease (IBD) was made, and upper and lower gastrointestinal endoscopy was performed. Histopathological evaluation of the lower gastrointestinal tract revealed nonspecific inflammatory changes. Stool calprotectin level was 144 µg/g. The presence of seborrheic dermatitis-like lesions on the scalp suggested the possibility of LCH, and previous pathology samples were re-examined. There was no immunohistochemical staining for Langerhans cell markers in bowel biopsies, but strong positivity was detected in perianal biopsy samples. Immunohistochemical analysis revealed positive BRAF expression. Imaging to assess systemic involvement revealed a contrast-enhancing mass lesion on pituitary magnetic resonance imaging. A staging study was performed to determine risk organ involvement. Given the absence of liver, spleen, and bone marrow involvement, the disease was classified as risk organ-negative multisystem LCH (RO-MS-LCH). Conclusion: This case highlights the need to consider multiple systemic disorders, particularly Langerhans cell histiocytosis (LCH), in children presenting with gastrointestinal and perianal symptoms suggestive of inflammatory bowel disease (IBD), especially in the presence of atypical skin lesions and the absence of histopathological confirmation. Early and comprehensive clinical evaluation plays a key role in preventing diagnostic delays and initiating appropriate treatment in a timely manner.