title: Multiple myeloma as a major cause of false-positive galactomannan tests in adult patients with cancer.
abstract: OBJECTIVE
  The galactomannan (GM) test is a useful method for early diagnosis of invasive aspergillosis. Recently, multiple myeloma has newly been suggested to be related to false-positive results of GM. We performed a case-control study to validate this finding.
  
  
  METHODS
  Electronic medical records were reviewed for patients admitted March through June 2014. Patients with false-positive GM results were selected as cases and those with negatives as controls. To verify the results of the four-month analysis, additional analysis was performed in multiple myeloma patients over a three-year period.
  
  
  RESULTS
  There were 30 false-positive and 316 negative cases during the four-month period. Among the factors evaluated, multiple myeloma was the only significant factor in the adjusted analysis (OR = 3.59, CI 1.28-10.04). In the three-year analysis of 145 multiple myeloma patients, 25.5% showed false-positive results, which was 3 times higher than overall. GM false-positivity was not related to serum monoclonal protein level or type of immunoglobulin. GM optical density indexes (ODIs) in all false positives were lower than 3.0.
  
  
  CONCLUSIONS
  Multiple myeloma was a major cause of GM false-positivity in adult cancer patients. GM was false-positive in 25.5% of multiple myeloma patients with GM ODIs lower than 3.0.
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Ko
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea. Electronic address: krpeck@skku.edu.
authors.forename: Kyong Ran
authors.initials: KR
authors.lastname: Peck
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Ji Yong
authors.initials: JY
authors.lastname: Lee
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Sun Young
authors.initials: SY
authors.lastname: Cho
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Young Eun
authors.initials: YE
authors.lastname: Ha
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Cheol-In
authors.initials: CI
authors.lastname: Kang
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Doo Ryeon
authors.initials: DR
authors.lastname: Chung
authors.affiliation: Division of Hematology-Oncology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Kihyun
authors.initials: K
authors.lastname: Kim
authors.affiliation: Department of Laboratory Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea.
authors.forename: Eun-Suk
authors.initials: ES
authors.lastname: Kang
authors.affiliation: Division of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, 81 Irwon-ro, Gangnam-gu, Seoul 135-710, Republic of Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Song
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D005189:False Positive Reactions; D005260:Female; D005690:Galactose / Q000031:analogs & derivatives; D006801:Humans; D055744:Invasive Pulmonary Aspergillosis / Q000175:diagnosis*; D008297:Male; D008351:Mannans / Q000097:blood*; D008875:Middle Aged; D009101:Multiple Myeloma / Q000473:pathology*; D055815:Young Adult
chemical_list: D008351:Mannans; C012990:galactomannan; D005690:Galactose
keywords: Adult; Cancer; False positive; Galactomannan; Multiple myeloma