Rationale

Elevated hemoglobin levels may be a manifestation of polycythemia vera or secondary erythrocytosis. Elevated hemoglobin levels may be due to many treatable causes. Unrecognized polycythemia may cause end-organ damage.

Causal Conditions

(list not exhaustive)

1. Red cell mass increased

   1. Polycythemia vera – low or normal erythropoetin (EPO)

   2. Secondary erythrocytosis – elevated EPO

      • Appropriate EPO elevation (e.g., hypoxemia)

      • Inappropriate EPO elevation (e.g., EPO secreting tumour)

   3. Relative polycythemia (decreased plasma volume)

Key Objectives

Given a patient with elevated hemoglobin levels, the candidate will diagnose the cause, severity, and complications, and will initiate an appropriate management plan.

Enabling Objectives

Given a patient with elevated hemoglobin level, the candidate will

1. list and interpret critical clinical findings, including

   1. differentiating between primary and secondary erythrocytosis;

   2. assessing the presence of complications;

2. list and interpret critical investigations, including

   1. appropriate laboratory and diagnostic imaging;

3. construct an effective initial management plan, including

   1. referring the patient for specialized care, if necessary;

   2. counselling and education (e.g., smoking cessation, work environment).