title: Quantitative polymerase chain reaction detection of circulating DNA in serum for early diagnosis of mucormycosis in immunocompromised patients.
abstract: BACKGROUND
  The aim of our study was to assess the detection of circulating DNA from the most common species of Mucorales for early diagnosis of mucormycosis in at-risk patients.
  
  
  METHODS
  We retrospectively evaluated a combination of 3 quantitative polymerase chain reaction (qPCR) assays using hydrolysis probes targeting Mucor/Rhizopus, Lichtheimia (formerly Absidia), and Rhizomucor for circulating Mucorales detection. Serial serum samples from 10 patients diagnosed with proven mucormycosis (2-9 samples per patient) were analyzed.
  
  
  RESULTS
  No cross-reactivity was detected in the 3 qPCR assays using 19 reference strains of opportunistic fungi, and the limit of detection ranged from 3.7 to 15 femtograms/10 µL, depending on the species. DNA from Mucorales was detected in the serum of 9 of 10 patients between 68 and 3 days before mucormycosis diagnosis was confirmed by histopathological examination and/or positive culture. All the qPCR results were concordant with culture and/or PCR-based identification of the causing agents in tissue (Lichtheimia species, Rhizomucor species, and Mucor/Rhizopus species in 4, 3, and 2 patients, respectively). Quantitative PCR was negative in only 1 patient with proven disseminated mucormycosis caused by Lichtheimia species.
  
  
  CONCLUSIONS
  Our study suggests that using specific qPCR targeting several species of Mucorales according to local ecology to screen at-risk patients could be useful in a clinical setting. The cost and efficacy of this strategy should be evaluated. However, given the human and economic cost of mucormycosis and the need for rapid diagnosis to initiate prompt directed antifungal therapy, this strategy could be highly attractive.
authors: CNRS-Université de Franche-Comté, UMR 6249 Chrono-environnement, Besançon, France. laurence.millon@univ-fcomte.fr
authors: Laurence
authors: L
authors: Millon
authors: Fabrice
authors: F
authors: Larosa
authors: Quentin
authors: Q
authors: Lepiller
authors: Faezeh
authors: F
authors: Legrand
authors: Steffi
authors: S
authors: Rocchi
authors: Etienne
authors: E
authors: Daguindau
authors: Emeline
authors: E
authors: Scherer
authors: Anne-Pauline
authors: AP
authors: Bellanger
authors: Joel
authors: J
authors: Leroy
authors: Frederic
authors: F
authors: Grenouillet
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D004271:DNA, Fungal / Q000097:blood*; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D057230:Limit of Detection; D008297:Male; D008875:Middle Aged; D009090:Mucorales / Q000235:genetics* / Q000302:isolation & purification; D009091:Mucormycosis / Q000097:blood* / Q000276:immunology / Q000382:microbiology*; D016533:Mycological Typing Techniques / Q000379:methods*; D016133:Polymerase Chain Reaction / Q000379:methods*; D015203:Reproducibility of Results; D012189:Retrospective Studies
chemical_list: D004271:DNA, Fungal