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Paroxysmal nocturnal haemoglobinuria

Last reviewed: 13 Feb 2025
Last updated: 19 Jan 2024

Summary

Definition

History and exam

Key diagnostic factors

  • haemoglobinuria
  • Budd-Chiari syndrome
  • thrombosis
Full details

Other diagnostic factors

  • history of aplastic anaemia
  • fatigue
  • anaemia
  • abdominal pain
  • dysphagia and odynophagia
  • erectile dysfunction
  • dyspnoea
  • infections
  • bleeding diathesis
  • neurological signs and symptoms
Full details

Risk factors

  • aplastic anaemia/hypoplastic bone marrow
  • myelodysplasia
Full details

Diagnostic investigations

1st investigations to order

  • urine dipstick
  • urine microscopy
  • FBC
  • reticulocyte count
  • serum LDH
  • unconjugated bilirubin
  • D-dimer
Full details

Investigations to consider

  • haptoglobin
  • flow cytometry for glycosylphosphatidylinositol anchor or anchored proteins
  • fluorescent aerolysin
  • immunotyping
  • antiglobulin (Coombs) test
  • serum iron, serum ferritin
  • serum creatinine and urea
Full details

Treatment algorithm

ACUTE

classic PNH (haemolytic anaemia): non-pregnant

classic PNH (haemolytic anaemia): pregnant

PNH in the setting of another specific bone marrow disorder: non-pregnant

PNH in the setting of another specific bone marrow disorder: pregnant with thrombosis

PNH in the setting of another specific bone marrow disorder: pregnant without thrombosis

subclinical PNH: non-pregnant

subclinical PNH: pregnant

ONGOING

following acute clinical PNH with thrombosis: non-pregnant

Contributors

Authors

Ibrahim Ibrahim, MD

Associate Professor

Internal Medicine

UT Southwestern

Dallas

TX

Disclosures

Taha Bat, MD

​Assistant Professor

Internal Medicine

UT Southwestern

Dallas

TX

Disclosures

TB serves on advisory boards for Alexion Pharmaceuticals. He is also the author of an article cited in this topic.

Acknowledgements

Dr Ibrahim and Dr Bat would like to gratefully acknowledge Dr Ilene Ceil Weitz and Dr Wendell F. Rosse, previous contributors to this topic.

Disclosures

WFR serves on advisory boards and educational faculties for Alexion Pharmaceuticals. ICW receives speaker honoraria from and undertakes consultancy for Alexion Pharmaceuticals.

Peer reviewers

David Dingli, MD, PhD

Associate Professor of Medicine

Mayo Clinic

Rochester

MN

Disclosures

DD declares that he has no competing interests.

Panayiotis D. Ziakas, MD, MSc, PhD

Department of Pathophysiology

Medical School

University of Athens

Athens

Greece

Disclosures

PDZ declares that he has no competing interests.

  • Differentials

    • Autoimmune haemolytic anaemia, warm antibody type
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    • Paroxysmal cold haemoglobinuria
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  • Guidelines

    • Paroxysmal nocturnal hemoglobinuria
    • Consensus guidelines to detect GPI‐deficient cells in paroxysmal nocturnal hemoglobinuria (PNH) and related disorders: Part 1 – clinical utility
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