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Updated: Jul 8, 2026
06:29
Methods for Quantitative Detection of Antibody-induced Complement Activation on Red Blood Cells
Published on: January 29, 2014
Severe antibody-mediated agranulocytosis
H Johnsen1, A Husebekk, T Skjelbakken
1Department of Medicine, University Hospital of North Norway, Tromsø, Norway.
International Journal of Laboratory Hematology
|January 15, 2008
Summary
A patient with Crohn's disease experienced severe neutropenia, a dangerous drop in white blood cells. Treatment with steroids and growth factors proved effective, suggesting an immune-mediated cause.
Area of Science:
- Hematology
- Immunology
- Gastroenterology
Background:
- Crohn's disease is a chronic inflammatory condition.
- Neutropenia, a low white blood cell count, can be life-threatening.
- Identifying the cause of neutropenia is crucial for effective treatment.
Observation:
- A 56-year-old female with Crohn's disease presented with fever and severe neutropenia.
- Initial treatments with antibiotics and granulocyte colony-stimulating factor (G-CSF) were ineffective.
- The patient improved with high-dose steroid therapy but relapsed upon dose reduction.
Findings:
- The patient's agranulocytosis (severe neutropenia) recurred despite G-CSF and low-dose steroids.
- High-dose methylprednisolone combined with filgrastim led to rapid recovery.
- Autoantibodies targeting early myeloid cells were suspected as the cause, despite a negative HNA-3a phenotype.
Implications:
- This case highlights a potential immune-mediated mechanism for neutropenia in Crohn's disease patients.
- Steroid therapy and G-CSF can be effective in managing such cases.
- Further research into autoantibodies against myeloid cells is warranted.
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