title: Congenital solitary histiocytoma: a variant of Hashimoto-Pritzker histiocytosis. A retrospective study of 8 cases.
abstract: BACKGROUND
  Self-healing solitary-lesion Hashimoto-Pritzker histiocytosis (HPH), a rare, congenital, purely cutaneous Langerhans histiocytosis (only 30 cases reported), carries a good prognosis.
  
  
  OBJECTIVE
  To describe the clinical and histopathological characteristics of solitary HPH.
  
  
  METHODS
  To conduct a retrospective, observational study on 8 affected newborns.
  
  
  RESULTS
  For these infants, with otherwise normal physical examinations, the unique nodule or papule (5-15-mm diameter) was congenital. Systematic routine histological examination of the lesions found dermal infiltrates constituted predominantly of histiocytes with lymphocytes and eosinophils. Protein S100 and CD1a immunolabelings, done for 7 patients, were positive. Electron microscopy (n = 4) observed Birbeck granules. No visceral involvement or recurrence has ever been observed after 2-12 years of follow-up.
  
  
  CONCLUSIONS
  Because of its self-healing nature, congenital solitary HPH frequency has probably been underestimated. In the absence of systemic involvement, regular physical examination for at least 2 years seems a valid approach.
authors.affiliation: Service de Dermatologie, Hôpital Robert-Debré, Reims, France.
authors.forename: C
authors.initials: C
authors.lastname: Zunino-Goutorbe
authors.forename: C
authors.initials: C
authors.lastname: Eschard
authors.forename: A
authors.initials: A
authors.lastname: Durlach
authors.forename: P
authors.initials: P
authors.lastname: Bernard
mesh_terms: D018949:Antigens, CD1 / Q000096:biosynthesis; D001706:Biopsy; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D015614:Histiocytosis / Q000151:congenital* / Q000276:immunology / Q000473:pathology; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D008854:Microscopy, Electron; D012189:Retrospective Studies; D009418:S100 Proteins / Q000096:biosynthesis; D012867:Skin / Q000378:metabolism / Q000648:ultrastructure
chemical_list: D018949:Antigens, CD1; C419393:CD1a antigen; D009418:S100 Proteins