Chapter 16 Laboratory Assessment

● multiple myeloma ● AIDS

● cirrhosis

The following drugs may decrease hematocrit levels: ●

●

chloramphenicol penicillin

Hemoglobin

Normal Values ●

● Women: 12 to 16 g/dL; 7.4 to 9.9 mmol/L (SI) (5)

Men: 14 to 18 g/dL; 8.7 to 11.2 mmol/L (SI) (5) Nutritional Significance

The hemoglobin concentration is a measure of the total amount of hemoglobin in the peripheral blood and is a more direct measure of iron deficiency than hematocrit. Changes in hydration status affect hemoglobin. Overhydration decreases the concentration, and dehy- dration increases it. Living in high altitudes may cause higher hemoglobin values (1).

● ●

Hemoglobin concentration increases with (1): dehydration polycythemia

● chronic obstructive pulmonary disease (COPD) ● CHF

● ●

high altitudes severe burns

Hemoglobin concentration decreases with (1): ●

anemias ➤ ➤ ➤ ➤ ➤

iron-deficiency anemia anemia of chronic disease pernicious anemia

megaloblastic anemia sickle cell anemia

● hypertension (HTN) cirrhosis

● ●

systemic diseases leukemia lymphoma

➤ ➤ ● ➤ ➤ ➤ ➤ ● ● erythematous

Hodgkin’s disease sarcoidosis

systemic lupus

overhydration kidney disease

● chronic hemorrhage ● ● ● ● ● splenomegaly ● AIDS

The following drugs may increase hemoglobin levels (1): ●

gentamicin ● methyldopa

The following drugs may decrease hemoglobin levels (1): ●

● ● ● ● ●

sulfonamides antibiotics aspirin

antineoplastic indomethacin rifampin

Mean Corpuscular Volume

Normal Values ●

80 to 95 μm3 ; 80 to 95 fL (SI) (5) Nutritional Significance

Mean corpuscular volume (MCV) is a measure of the average volume of a single red blood cell. MCV is determined by dividing the hematocrit by the total red blood cell count. An increased MCV suggests that the red blood cells are macrocytic. Megaloblastic anemia (B-12 and folic acid deficiency) is associated with ele- vated MCV. A low MCV suggests that the red blood cells are microcytic. Iron-deficiency anemia and thalas- semia are associated with decreased MCV (1,6).

● ● ● ● ● ●

MCV increases with (1,6): liver disease

folate deficiency B-12 deficiency

excess alcohol intake celiac sprue

early pernicious anemia

MCV decreases with (1,6): ●

advanced iron deficiency chronic blood loss iron malabsorption

excessive iron requirements thalassemia

lead poisoning

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