The 27 System Ogran classes (MedDRA)

This post is part of 'Domain | General' series

The MedDRA system organ class is defined as the highest level of the MedDRA terminology, distinguished by anatomical or physiological system, aetiology (disease origin) or purpose. Most of these describe disorders of a specific part of the body. For example:

  • Cardiac disorders describe heart problems
  • Renal and urinary disorders describe kidney and bladder problems
  • Some of the system organ classes are not related to a particular part of the body. For example:
    • investigations describes laboratory tests and other medical investigations that gave an unusual reading
    • neoplasms describes any type of growth, including cancer, no matter where it appears in the body.
  1. Blood and lymphatic system disorders
  2. Cardiac disorders
  3. Congenital, familial and genetic disorders
  4. Ear and labyrinth disorders
  5. Endocrine disorders
  6. Eye disorders
  7. Gastrointestinal disorders
  8. General disorders and administration site conditions
  9. Hepatobiliary disorders
  10. Immune system disorders
  11. Infections and infestations
  12. Injury, poisoning and procedural complications
  13. Investigations
  14. Metabolism and nutrition disorders
  15. Musculoskeletal and connective tissue disorders
  16. Neoplasms benign, malignant and unspecified (incl cysts and polyps)
  17. Nervous system disorders
  18. Pregnancy, puerperium and perinatal conditions
  19. Psychiatric disorders
  20. Renal and urinary disorders
  21. Reproductive system and breast disorders
  22. Respiratory, thoracic and mediastinal disorders
  23. Skin and subcutaneous tissue disorders
  24. Social circumstances
  25. Surgical and medical procedures
  26. Vascular disorders
  27. Product issues.

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