Recurrent bacterial pneumonia due to immunoglobulin G2 subclass deficiency after allogeneic hematopoietic stem cell transplantation: Efficacy of immunoglobulin replacement

Abstract

Immunoglobulin (Ig) G2 subclass deficiency is known to be associated with recurrent bacterial respiratory infections caused by capsulated bacteria. We encountered a case of recurrent pneumonia due to Streptococcus pneumoniae after allogeneic hematopoietic stem cell transplantation (HSCT). IgG2 subclass level was specifically low, and prophylactic Ig replacement successfully prevented subsequent infections. However, the cessation of Ig replacement resulted in subsequent pneumonia. These findings suggested that IgG2 deficiency could be a cause of recurrent pneumococcal infection after allogeneic HSCT.

Impact of immunoglobulin G2 subclass level on late‐onset bacterial infection after allogeneic hematopoietic stem cell transplantation

“…In the present study, a suboptimal serum IgG2 level was shown to be a possible risk factor for late‐onset bacterial pneumonia after allogeneic HSCT, which could reinforce our previous finding . In addition, the administration of rituximab in the peri‐transplant period and cord blood transplantation were each significantly associated with a suboptimal IgG2 level and a suboptimal IgG2/IgG ratio.…”

“…In the setting of HSCT, we recently reported a case of recurrent bacterial pneumonia developing more than 2 years after transplantation. In this case, the IgG2 level was low and intravenous Ig (including an IgG2 subclass component) successfully prevented the subsequent onset of pneumonia . A limited number of studies have evaluated the dynamics of IgG subclass after allogeneic HSCT.…”

“…In the setting of allogeneic HSCT, suboptimal levels of particular IgG subclasses such as IgG2 and IgG4 have been reported to be sustained after transplantation . Recently, we reported a case of recurrent bacterial pneumonia caused by S pneumoniae after allogeneic HSCT, in which a long‐lasting IgG2 deficiency was considered to be a primary cause and prophylactic Ig replacement successfully prevented subsequent infection . However, the relationship between IgG2 subclass deficiency and susceptibility to bacterial infection has not been systematically evaluated in the setting of allogeneic HSCT.…”

Role of antibodies in confining cytomegalovirus after reactivation from latency: three decades’ résumé

“…The impact of IVIG on GVHD has been attributed to the immune-modulatory effects of IVIG. However, it should be noted that utilization of IVIG in the posttransplant period to correct deficiencies in immunoglobulin deficiencies appears to be an accepted use of these preparations in some transplant centers [67][68][69][70][71][72].…”

Secondary immunodeficiencies with predominant antibody deficiency: multidisciplinary perspectives of Polish experts

“…In this group of patients, SIDs are common, with usually complex pathogenesis, appearing early after transplantation, and may persist for months or even years. Depending on time after transplantation, a deficiency of immunocompetent cells, deficiency of antibodies, or mixed deficiency might dominate [21][22][23]. Many pre-and post-transplantation factors influence immune restoration, including the recipient's age, underlying disease diagnosis and its advancement at the time of transplantation, previously used methods of treatment, degree of HLA compatibility between the recipient and donor, source of hematopoietic cells, intensity of conditioning, carriage of latent viruses (especially CMV and EBV) by the recipient and donor, and development of graft-versus-host disease [21].…”