Evolution of immunoglobulin and mannose binding protein levels after renal transplantation: association with infectious complications

Abstract

Summary Hypogammaglobulinemia (hypo‐Ig) and low mannose binding protein (MBP) levels might be involved in the infectious risk in renal transplantation. In 152 kidney transplant recipients treated with calcineurin inhibitors (CNI) and mycophenolate mofetil (MMF), during the first year, we prospectively recorded the incidence of hypogammaglobulinemia, and low MBP levels. Their influence on infectious complications was evaluated in 92 patients at 3 and 12 months (T3 and T12). The proportion of deficiency increased significantly: hypo‐IgG: 6% (T0), 45% (T3), and 30% (T12) (P < 0.001); hypo‐MBP: 5%, 11%, and 12% (P = 0.035). Hypo‐IgG at T3 was not associated with an increased incidence of first‐year infections. A significantly higher proportion of patients with combined hypogammaglobulinemia [IgG+ (IgA and/or IgM)] at T3 and with isolated hypo‐IgG at T0 developed infections until T3 compared with patients free of these deficits (P < 0.05). Low MBP levels at T3 were associated with more sepsis and viral infections. Hypogammaglobulinemia is frequent during the first year after renal transplantation in patients treated with a CNI and MMF. Hypo‐IgG at T0 and combined Igs deficts at T3 were associated with more infections. MBP deficiency might emerge as an important determinant of the post‐transplant infectious risk.

Monitoring of Immunoglobulin Levels Identifies Kidney Transplant Recipients at High Risk of Infection

“…This effect of MMF on the humoral immunity was later observed in other types of SOT (27,28). Nevertheless, neither this study nor that of Broeders et al (15) found any significant association between the type of maintenance immunosuppression and the risk of HGG. It has been suggested that the decrease in helper T cell population after antirejection therapy may lead to acquired posttransplant HGG.…”

“…The presence of HGG of any class at month 1 was independently associated with the incidence of bacterial infection during the intermediate posttransplant period, whereas HGG at month 6 was associated with either overall infection or bacterial infection in the late period. The literature contains some studies aimed at assessing the incidence and relevance of HGG after KT (12)(13)(14)(15). Most of them, however, were performed more than a decade ago (12)(13)(14), thus limiting the validity of their findings in the setting of contemporary immunosuppressive and prophylactic practices, or were based on small sample sizes (13,14).…”

“…Most of them, however, were performed more than a decade ago (12)(13)(14), thus limiting the validity of their findings in the setting of contemporary immunosuppressive and prophylactic practices, or were based on small sample sizes (13,14). Of note, the definition used for HGG was not uniform across this literature and some recent studies did not perform an accurate analysis by site of infection or etiologic agent (15). The only other study that specifically stratified the impact of immunoglobulin levels at different times found that patients with HGG at month 3 suffered from a higher incidence of infection during the first 3 months after transplantation, but not in the subsequent period (months 4-12), raising reasonable concerns about the actual sense of the causal relationship between both events.…”

“…The only other study that specifically stratified the impact of immunoglobulin levels at different times found that patients with HGG at month 3 suffered from a higher incidence of infection during the first 3 months after transplantation, but not in the subsequent period (months 4-12), raising reasonable concerns about the actual sense of the causal relationship between both events. In addition, these authors only analyzed some types of posttransplant infectious complications-mainly urinary tract infectionwith low number of patients in each subgroup (15). Finally, our study contains the largest sample size and longest follow-up period, and one of the few demonstrating the independent effect of humoral immune function on the risk of infection by means of logistic regression analysis.…”

“…Additionally the immunosuppressive drugs required to prevent allograft rejection contribute to the development of acquired hypogammaglobulinemia (HGG) in kidney transplant (KT) recipients (9)(10)(11). Only a few previous studies have evaluated the impact of humoral immune function on the risk of infection after KT (12)(13)(14)(15). We undertook the present work to prospectively assess the incidence, timing, predisposing factors and clinical significance of HGG in KT recipients.…”