title: Mannose-binding lectin 2 polymorphisms do not influence frequency or type of infection in adults with chemotherapy induced neutropaenia.
abstract: BACKGROUND
  Mannose-binding Lectin protein (MBL) has been suggested to be relevant in the defence against infections in immunosuppressed individuals. In a Swedish adult cohort immunosuppressed from both the underlying disease and from iatrogenic treatments for their underlying disease we investigated the role of MBL in susceptibility to infection.
  
  
  METHODS
  In this cross sectional, prospective study, blood samples obtained from 96 neutropaenic febrile episodes, representing 82 individuals were analysed for single nucleotide polymorphism (SNP) in the MBL2 gene. Concurrent measurement of plasma MBL protein concentrations was also performed for observation of acute response during febrile episodes.
  
  
  RESULTS
  No association was observed between MBL2 genotype or plasma MBL concentrations, and the type or frequency of infection. Adding to the literature, we found no evidence that viral infections or co-infections with virus and bacteria would be predisposed by MBL deficiency. We further saw no correlation between MBL2 genotype and the risk of fever. However, fever duration in febrile neutropaenic episodes was negatively associated with MBL2 SNP mutations (p<0.05). Patients with MBL2 SNP mutations presented a median febrile duration of 1.8 days compared with 3 days amongst patients with wildtype MBL2 genotype.
  
  
  CONCLUSIONS
  We found no clear association between infection, or infection type to MBL2 genotypes or plasma MBL concentration, and add to the reports casting doubts on the benefit of recombinant MBL replacement therapy use during iatrogenic neutropaenia.
authors.affiliation: Infectious Disease Unit, Department of Medicine, Karolinska University Hospital, Karolinska Institutet, Stockholm, Sweden. michelle.wong@ki.se
authors.forename: Michelle
authors.initials: M
authors.lastname: Wong
authors.forename: Lars
authors.initials: L
authors.lastname: Öhrmalm
authors.forename: Kristina
authors.initials: K
authors.lastname: Broliden
authors.forename: Carl
authors.initials: C
authors.lastname: Aust
authors.forename: Martin
authors.initials: M
authors.lastname: Hibberd
authors.forename: Thomas
authors.initials: T
authors.lastname: Tolfvenstam
mesh_terms: D000328:Adult; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000009:adverse effects*; D002097:C-Reactive Protein / Q000378:metabolism; D005334:Fever / Q000097:blood / Q000150:complications / Q000235:genetics / Q000382:microbiology; D005787:Gene Frequency / Q000235:genetics; D005838:Genotype; D006801:Humans; D007239:Infections / Q000097:blood / Q000453:epidemiology* / Q000235:genetics* / Q000382:microbiology; D037601:Mannose-Binding Lectin / Q000097:blood / Q000235:genetics*; D009503:Neutropenia / Q000139:chemically induced* / Q000150:complications / Q000235:genetics / Q000382:microbiology; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D013548:Sweden / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents; D000970:Antineoplastic Agents; C445619:MBL2 protein, human; D037601:Mannose-Binding Lectin; D002097:C-Reactive Protein