Acquired inhibitor against factor IX in a child: Successful treatment with high-dose immunoglobulin and dexamethasone

M. G. Mazzucconi, M. Peraino, L. Bizzoni, S. Bernasconi, M. Luciani, G. De Rossi

Research output: Contribution to journalArticle


The occurrence of acquired inhibitor against factor IX:C is infrequent in haemophilia B patients and is very rare in previously healthy subjects, in whom it is often related to underlying diseases. We describe the case of a 2-year-old girl, who was referred to our hospital with haematomas, without previous bleeding history. Prolonged APTT, normal PT and a factor IX:C level below 1% were found. An inhibitor against factor IX:C was detected (5.5 U mL-1. Her father and mother showed normal factor IX:C levels. Treatment with high-dose immunoglobulin (400 mg kg-1 day-1 for 5 consecutive days by intravenous infusion) and dexamethasone (4 mg three times a day by intravenous injection for 4 consecutive days) normalized factor IX:C levels and overcame the inhibitor. In conclusion, high-dose immunoglobulin and high-dose dexamethasone are a successful and safe immunosuppressive approach for recovery from inhibitor occurrence.

Original languageEnglish
Pages (from-to)132-134
Number of pages3
Issue number2
Publication statusPublished - 1999



  • Acquired coagulation inhibitors
  • Dexamethasone
  • High-dose Ig
  • Immunosuppressive therapy
  • Inhibitors to factor IX:C

ASJC Scopus subject areas

  • Hematology

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