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

Rie Yamazaki, Taku Kikuchi, Jun Kato, Masatoshi Sakurai, Yuya Koda, Risa Hashida, Yusuke Yamane, Ryohei Abe, Naoki Hasegawa, Shinichiro Okamoto, Takehiko Mori

Research output: Contribution to journalArticle

2 Citations (Scopus)


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.

Original languageEnglish
JournalTransplant Infectious Disease
Publication statusAccepted/In press - 2018 Jan 1



  • Allogeneic hematopoietic stem cell transplantation
  • Immunoglobulin G2 deficiency
  • Pneumonia
  • Streptococcus pneumoniae

ASJC Scopus subject areas

  • Transplantation
  • Infectious Diseases

Cite this