Mannose-binding lectin does not act as an acute-phase reactant in adults with community-acquired pneumococcal pneumonia

Abstract

SummaryThe objective of this work was to study the role of mannose-binding lectin (MBL) and C-reactive protein (CRP) in pneumococcal pneumonia, to determine whether MBL acts as an acute-phase reactant and whether the severity of the disease correlates with MBL levels. The study comprised 100 patients with pneumococcal pneumonia. The pneumonia severity score was calculated and graded into a risk class of mortality (Fine scale). The MBL genotypes and the levels of MBL and CRP at the acute and recovery phases were determined. Fifty patients with the wild-type MBL genotype showed higher MBL levels in each phase ( P < < < < 0·001) and an increased risk to developing bacteraemia, odds ratio (

Acute-phase responsiveness of mannose-binding lectin in community-acquired pneumonia is highly dependent uponMBL2genotypes

“…The promoter X SNP is thought to hamper this up-regulation. The influence of the X/Y promoter SNP on the capability of mounting an acutephase response could be an explanation for the heterogeneity in MBL acute-phase responsiveness described in the studies above [10][11][12]. Our results are in accordance with a previous study showing that the capacity to increase MBL levels from day 1 to day 5 of febrile neutropenia in paediatric oncology patients was associated with the HY promoter haplotype [13].…”

“…However, 58·6% of the patients showed an acute-phase response either by increased (31·4%) or by decreased (27·3%) MBL levels in the acute phase. It was also found that, in communityacquired pneumococcal pneumonia, MBL did not act uniformly as an acute-phase reactant in all patients and no correlation with CRP levels was found [12].…”

“…However, this has been debated extensively, as MBL responses have shown a high degree of heterogeneity. Conflicting results have been described in postoperative patients [8][9][10], patients with severe infections [11] and patients with community-acquired pneumonia (CAP) [12]. Although some of these studies considered MBL2 exon 1 polymorphisms in the analysis, none of them reported the influence of the X/Y promoter SNP on MBL acute-phase responsiveness in individual patients.…”

The role of mannose-binding lectin in pneumococcal infection

“…We also analysed data from another Spanish population included in a previously published study [19]. A total of 84 P-CAP patients (51.19% with bacteraemic P-CAP), and a group of 91 healthy controls were compared for MBL2 genotypes.…”

“…These patients were included in a published study [19], but several patients were excluded on the basis of our inclusion/ exclusion criteria. A group of 91 healthy controls from the same origin were also used (64.95¡18.61 yrs, 72.5% females).…”