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URL of this page: //medlineplus.gov/ency/presentations/100152.htm

Complete blood count - series—Results, part 2

Results, part 2

Overview

High numbers of red blood cells may indicate:

  • Cigarette smoking
  • Low oxygen tension in the blood
  • Congenital heart disease
  • Cor pulmonale
  • Pulmonary fibrosis
  • Polycythemia vera
  • Dehydration (such as from severe diarrhea)
  • Emphysema

Review Date 6/3/2025

Updated by: Ramin Fathi, MD, FAAD, Director, Phoenix Surgical Dermatology Group, Phoenix, AZ. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.

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