title: Frequency and development of CNS involvement in Chinese children with hemophagocytic lymphohistiocytosis.
abstract: BACKGROUND
  We investigated the characteristics, frequency, and prognosis of central nervous system (CNS) involvement in patients with hemophagocytic lymphohistiocytosis (HLH).
  
  
  METHODS
  Neurological manifestations were prospectively assessed in 92 children with HLH treated from January 2004 to August 2008 at our center; 82 (89%) had associated viral infections (69 Epstein-Barr virus), one empyema, while no associated disease was identified in the remaining nine. Prior to treatment, all underwent cerebrospinal fluid (CSF) evaluation, brain computer tomography (CT) and/or magnetic resonance imaging (MRI).
  
  
  RESULTS
  At diagnosis, 43 (47%) children had CNS involvement. Twelve patients (13%) had neurological symptoms, including seizures, ataxia, coma, cranial nerve palsy, and hemiplegia. All patients improved after 8 weeks of therapy, but one later developed progressive neurological symptoms and six discontinued therapy due to progressive systemic symptoms and/or other reasons. Fifteen patients had CSF abnormalities that all normalized completely after 6 weeks of treatment. Thirty-six patients (39%) had neuroradiological abnormalities; with 5 still under treatment, 15 lost to follow-up, and 16 followed after completion of therapy. Of these 16, 12 improved, 3 were unchanged, and 1 progressed. Among all 21 children with CNS involvement followed after completion of therapy, 10 recovered completely, 10 improved (3 had remaining neuroradiological abnormalities), and 1 progressed clinically and neuroradiologically.
  
  
  CONCLUSIONS
  Most patients reported here suffered from secondary HLH and since CNS involvement is frequent in HLH, brain MRI at diagnosis is recommended in all HLH patients. Clinical and CSF abnormalities often improved within 8 weeks of therapy, but CT/MRI abnormalities normalized more slowly and less frequently.
authors.affiliation: Hemopathy Center, Beijing Children's Hospital, Capital Medical University, Beijing, China. yangshuang-1118@hotmail.com
authors.forename: Shuang
authors.initials: S
authors.lastname: Yang
authors.forename: Li
authors.initials: L
authors.lastname: Zhang
authors.forename: Chenguang
authors.initials: C
authors.lastname: Jia
authors.forename: Honghao
authors.initials: H
authors.lastname: Ma
authors.forename: Jan-Inge
authors.initials: JI
authors.lastname: Henter
authors.forename: Kunling
authors.initials: K
authors.lastname: Shen
mesh_terms: D002493:Central Nervous System Diseases / Q000134:cerebrospinal fluid / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000209:etiology*; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007223:Infant; D051359:Lymphohistiocytosis, Hemophagocytic / Q000134:cerebrospinal fluid / Q000150:complications* / Q000175:diagnosis / Q000000981:diagnostic imaging; D008297:Male; D011446:Prospective Studies; D011859:Radiography