chapter 20 - introduction to increased destruction of erythrocytes

increased destruction of RBCs in the blood, bone marrow, or spleen

“hemolytic disorder“ in general refers to a disorder in which there is:

macrophage-mediated

RBC destruction that occurs when macrophages ingest & destroy RBCs

elevated urinary urobilinogen level

sign of hemolysis that is typically associated with both fragmentation & macrophage-mediated hemolysis

yellow skin & eyes

elderly px — evaluated for worsening anemia; decrease of approximately 0.5 mg/dL of Hgb each week

• pale

• skin & eyes are slightly yellow

• extreme fatigue

• unable to complete daily living tasks without napping in midmorning & midafternoon

• tires with exertion — finding it difficult to climb even 5 stairs

which of the features of this description points to a hemolytic cause of anemia?

reticulocyte count

test that provides a good indication of accelerated erythropoiesis

acquired, fragmentation

5 year old px — seen by provider several days before current visit; diagnosed with pneumonia

• prescribed with standard cause of antibiotics

• returned to provider again — px’s urine began to darken after first visit, and now is alarmingly dark

• has no history of anemia

• no family history of any hematologic disorder

CBC

• mild anemia

• polychromasia

• few schistocytes

category of anemia?

spherocytes on blood film

px

• personal & family history of mild hemolytic anemia

blood results

• consistently elevated levels of

  • total & indirect serum bilirubin

  • urinary urobilinogen

• serum haptoglobin level — consistently decreased

• reticulocyte count — elevated

  • can be seen as polychromasia on px’s peripheral blood film

• spherocytes are noted

which finding reported is INCONSISTENT with classical diagnosis of fragmentation hemolysis?

macrophage-secreted indirect bilirubin

under physiologic conditions, major fraction of bilirubin in the plasma is

evidence of increased protoporphyrin catabolism is lacking

px

• anemia that has been worsening over the last several months

blood results

• Hgb — declining slowly

  • drop of 1.5 g/dL of Hgb over about 6 weeks

• peripheral blood film

  • polychromasia

  • anisocytosis

  • consistent with

    • elevated reticulocyte count

    • RDW

• serum levels of total & indirect bilirubin — within reference intervals

• urinary urobilinogen — normal

when findings were elevated, it is concluded that anemia does not have hemolytic component.

based on data given, why was hemolysis ruled out as cause of anemia?

serum haptoglobin — decreased

urine hemoglobin — positive

urine sediment prussian blue stain — positive

test results that is typically expected with chronic fragmentation hemolysis