Acquired C1-inhibitor deficiency presenting with nephrotic syndrome

BMJ Case Rep. 2019 Jul 11;12(7):e230388. doi: 10.1136/bcr-2019-230388.


Acquired C1-inhibitor (C1-INH) deficiency is a rare and potentially life-threatening disorder, which presents with recurrent attacks of non-pitting oedema to the face, airway, limbs or gastrointestinal tract. It is often associated with underlying B-cell lymphoproliferative disorders. We describe a case of a 73-year-old man with acquired C1-INH deficiency who presented with nephrotic syndrome due to glomerular IgM deposition, secondary to an underlying secretory lymphoplasmacytic lymphoma. Both the acquired C1-INH deficiency and the nephrotic syndrome resolved when the underlying B-cell lymphoma was treated with rituximab and bendamustine, suggesting the underlying lymphoproliferative malignancy was driving both disorders.

Keywords: haematology (incl blood transfusion); immunology; renal system.

Publication types

  • Case Reports

MeSH terms

  • Aged
  • Angioedemas, Hereditary / diagnosis*
  • Angioedemas, Hereditary / drug therapy
  • Angioedemas, Hereditary / etiology
  • Angioedemas, Hereditary / physiopathology
  • Antineoplastic Agents, Alkylating / therapeutic use*
  • Bendamustine Hydrochloride / therapeutic use*
  • Humans
  • Male
  • Nephrotic Syndrome / diagnosis*
  • Nephrotic Syndrome / drug therapy
  • Nephrotic Syndrome / etiology
  • Nephrotic Syndrome / physiopathology
  • Quality of Life
  • Return to Work
  • Rituximab / therapeutic use*
  • Treatment Outcome
  • Waldenstrom Macroglobulinemia / complications
  • Waldenstrom Macroglobulinemia / diagnosis*
  • Waldenstrom Macroglobulinemia / drug therapy
  • Waldenstrom Macroglobulinemia / physiopathology


  • Antineoplastic Agents, Alkylating
  • Rituximab
  • Bendamustine Hydrochloride