title: Falsely elevated serum antimüllerian hormone level in a context of heterophilic interference.
abstract: OBJECTIVE
  To describe a case of falsely elevated serum antimüllerian hormone (AMH) level in an infertile 37-year-old woman with rheumatoid arthritis.
  
  
  METHODS
  Case report.
  
  
  METHODS
  Lille University IVF center.
  
  
  METHODS
  A 37-year-old woman with rheumatoid arthritis demonstrating a high serum AMH level (74.5 ng/mL) and a low antral follicle count.
  
  
  METHODS
  Assay with a Heterophilic Blocking Tube (HBT) to avoid heterophilic interference.
  
  
  METHODS
  Serum AMH level, ultrasound antral follicle count, hormonal assays on the 4th day of a spontaneous cycle.
  
  
  RESULTS
  The results of the infertility workup were as follows: serum AMH: 74.5 ng/mL (15-fold the upper limit of normal) (immunoassay: Immunotech); LH: 3.2 IU/L; FSH: 4.5 IU/L; E2: 27 pg/mL; PRL: 10 ng/mL. The antral follicle count (follicles from 2 to 9 mm) at ultrasound was 7 for both ovaries. Because there were discrepancies between the serum AMH level and the results of the infertility workup using the bioassays, we suspected a case of falsely elevated AMH level due to heterophilic interference. An HBT tube revealed a serum AMH level of 0.63 ng/mL.
  
  
  CONCLUSIONS
  This case illustrates, for the first time, the possibility of a falsely high serum AMH level due to heterophilic interference.
authors: Department of Endocrine Gynecology and Reproductive Medicine, Hôpital Jeanne de Flandre, Centre Hospitalier Régional Universitaire, and Faculty of Medicine of Lille, University of Lille II, Lille, France.
authors: Hélène
authors: H
authors: Cappy
authors: Pascal
authors: P
authors: Pigny
authors: Maryse
authors: M
authors: Leroy-Billiard
authors: Didier
authors: D
authors: Dewailly
authors: Sophie
authors: S
authors: Catteau-Jonard
mesh_terms: D000328:Adult; D054304:Anti-Mullerian Hormone / Q000097:blood*; D000910:Antibodies, Heterophile / Q000097:blood*; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000097:blood / Q000175:diagnosis* / Q000378:metabolism*
chemical_list: D000910:Antibodies, Heterophile; D054304:Anti-Mullerian Hormone