- Normal: <1.0 mg/dl
- Increased (Unconjugated Hyperbilirubinemia)
- Increased Bilirubin production
- Large heme load (e.g. large Hematoma reabsorption)
- Rhabdomyolysis
- Hyperthyroidism (Thyrotoxicosis)
- Hemoglobinopathy (Thalassemia, Sickle Cell Anemia)
- Spherocytosis
- Hemolytic Anemia (typically mild Hyperbilirubinemia)
- Autoimmune Hemolytic Anemia
- Drug-Induced Hemolytic Anemia
- RBC enzyme disorders (e.g. G6PD Deficiency, pyruvate kinase deficiency, P5'N deficiency)
- Ineffective Erythropoiesis (increased RBC destruction in marrow)
- Pernicious Anemia
- Lead Poisoning
- Iron Deficiency Anemia
- Myeloproliferative Disorder
- Defective Bilirubin conjugation
- Neonatal Jaundice (immature liver)
- Gilbert's disease
- Crigler-Najjar syndrome
- Impaired hepatic uptake of Bilirubin
- Medications (e.g. Gemfibrozil, Indinavir)
- Portosystemic shunt
- Hepatic congestion (e.g .CHF, liver disease)