title: Glycopeptide-induced neutropenia: cross-reactivity between vancomycin and teicoplanin.
abstract: OBJECTIVE
  To report teicoplanin-related neutropenia that developed after an episode of neutropenia induced by vancomycin therapy.
  
  
  METHODS
  A 57-year-old female suffered from osteomyelitis of the left humerus, with a white blood cell (WBC) count of 2.8 x 10(3)/mm3 and absolute neutrophil count (ANC) of 0.28 x 10(3)/mm3, occurring after 24 days of vancomycin therapy. Vancomycin was changed to teicoplanin and the agranulocytosis resolved 4 days later. However, a new episode of neutropenia, with a WBC count of 2.8 x 10(3)/mm3 and ANC of 0.448 x 10(3)/mm3, occurred 11 days after teicoplanin initiation. Agranulocytosis resolved 4 days following withdrawal of teicoplanin.
  
  
  CONCLUSIONS
  Because of the close time relationship between drug administration and the development of symptoms and signs, as well as between drug withdrawal and changes in WBC count and ANC, the episodes of neutropenia were suspected to be drug related. Teicoplanin-induced agranulocytosis that followed vancomycin-induced agranulocytosis suggests a possible cross-reactivity between the 2 drugs. Both reactions were categorized as probable according to the Naranjo probability scale.
  
  
  CONCLUSIONS
  For all patients with vancomycin-induced neutropenia, possible cross-reactivity of teicoplanin should be monitored.
authors.affiliation: Department of Pharmacy, National Cheng Kung University Hospital, Taiwan, Republic of China.
authors.forename: Shu-Hwa
authors.initials: SH
authors.lastname: Hsiao
authors.forename: Chia-Ming
authors.initials: CM
authors.lastname: Chang
authors.forename: Jui-Chen
authors.initials: JC
authors.lastname: Tsai
authors.forename: Chia-Yin
authors.initials: CY
authors.lastname: Lin
authors.forename: Li-Hsiang
authors.initials: LH
authors.lastname: Liao
authors.forename: Wen-Liang
authors.initials: WL
authors.lastname: Lin
authors.forename: Ta-Jen
authors.initials: TJ
authors.lastname: Wu
mesh_terms: D000900:Anti-Bacterial Agents / Q000009:adverse effects*; D003429:Cross Reactions; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008875:Middle Aged; D009503:Neutropenia / Q000097:blood / Q000139:chemically induced*; D013207:Staphylococcal Skin Infections / Q000188:drug therapy; D013211:Staphylococcus aureus; D017334:Teicoplanin / Q000009:adverse effects*; D014640:Vancomycin / Q000009:adverse effects*
chemical_list: D000900:Anti-Bacterial Agents; D017334:Teicoplanin; D014640:Vancomycin