MISC 1 & 2 Flashcards
The erythrocyte sedimentation rate is increased in:
Pregnancy, severe anemia and multiple myeloma
The anticoagulant used in performing the Westergren ESR (erythrocyte sedimentation rate) is:
Sodium citrate
What causes a Wrights stained peripheral blood smear to appear “too pink”?
under buffering
When using a Romanowsky stain, what stains the leukocytes nuclear material?
basic dye
Which stain is used for staining thick smears for malaria parasites?
Giemsa stain
Hemolysis is greatest in which species of malaria?
P. falciparum
What stains make up a Romanowsky stains?
eosin and methylene blue
How are the results affected when the erythrocyte sedimentation tube is not placed exactly in the vertical position?
Increased
Which of the following would be classed as a non-technical factor that affects the ESR?
Size of red cells
How is Malaria transmitted?
Bite of the Anopheles mosquito
Which species of malaria prefers to infect only young RBC’s?
P. vivax and P. ovale
Which specie(s) of malaria prefers to infect only old RBC’s?
P. malariae
What is the major hemoglobin found in the RBC’s of a patient with Homozygous Sickle Cell anemia?
HGB S
What is measured by the ESR?
the settling of RBC’s in a specific period of time
How does the species P. vivax differ from P. falciparum?
Presence of a large ring for, enlargement of red cell, presence of schuffner’s dots
Which factors affect the result of the ESR?
The diameter of the tube, change in temperature more than 25C, anemia
How will cells appear in a blood smear, stained with Wright’s stain, when the pH of the buffer is 8.0?
Nuclei stained deep blue, red cells blue or greenish, eosinophil granules gray
What is the purpose of the phosphate buffer in the Wright’s stain?
dissociates the dyes to stain the various cellular elements
In P. falciparum, which stage is rarely found on the peripheral blood smear?
Schizont
What is the most common reason for blood smears having red cells that are gray and white cells that are barely visible?
Over-rinsing
What tests are used as a screening tool for sickle cell anemia?
hemoglobin/hematocrit, blood smear examination and HGB S solubility
Which stain is used to demonstrate siderocytes?
Perl’s Prussian Blue
What is the name of malarial life cycle that takes place in the mosquito?
Sexual cycle
What is the earliest age, sickle cells can be seen on the peripheral blood smear in a patient with homozygous sickle cell anemia?
6 months
To differentiate between homozygous and heterozygous sickle cell anemia, which one of these tests should be performed?
HGB electrophoresis
Which species of malaria is the most pathogenic and can cause death in 36 to 48 hours?
P. falciparum
Increased ESR is most affected by:
increased plasma proteins
In sickle cell anemia, what causes the abnormality in the beta chain of the hemoglobin molecule?
Replacement of glutamic acid by valine
What conditions may be associated with Sickle Cell disease?
Decreased red cell survival, positive hemoglobin solubility test, abnormal hgb electrophoresis
All the following would be expected 1 year after a splenectomy on a patient with severe hereditary spherocytosis EXCEPT
Reticulocyte count of 10%
What lab findings is exhibited with a patient with G6PD deficiency?
Precipitous HGB drop. normochromic, normocytic anemia, bite cells
What are Pappenheimer bodies composed of?
Ferric iron
What is the name of the enzyme needed to catalyze the first step in the pentose phosphate shunt/ Hexose Monophosphate Pathway?
Glucose-6-phosphate dehydrogenase
What are Heinz bodies composed of?
Denatured hemoglobin
What best describes a siderocyte?
Erythrocyte with Pappenheimer bodies
What inclusion body is composed of remnants of the mitotic spindle?
Cabot ring
What does the presence of spherocytes and polychromasia in the peripheral blood indicate?
Extravascular hemolysis
What does the presence of schistocytes in the peripheral blood indicate?
intravascular hemolysis
What diagnostic test would help diagnosis of a G6PD-deficient person in a hemolytic crisis?
Heinz body prep
What disorders are associated with Howell Jolly Bodies?
Hemoglobin S/S disease, hyposplenism, anemia of chronic disease
What defect is associated with Hereditary Spherocytosis (HS)?
Red cell membrane skeletal proteins
What is the purpose of performing a reticulocyte count?
Assessing the erythropoietic activity of the bone marrow
What are the primary molecular defects in Hereditary Spherocytosis?
Ankyrin, band 3, protein 4.2 and spectrin deficiency
What best describes Schistocytes?
RBC sheared from fibrin deposits
What stain is used to perform a manual reticulocyte count?
Supravital stain
What causes microcytes?
Impaired Hb synthesis in BM
What causes sickle cells?
Deoxygenation causes polymerization of Hb distorting RBC
What are Sideroblastic granules composed of?
Iron granules
What are coverslip smears used primarily for
bone marrow aspirates
What is suggested by the presence of polychromatophilic red blood cells (RBCs) on a blood film?
reticulocyte count will be increase and there is enhanced bone marrow erythropoiesis
What patient condition causes macroscopic holes in a blood smear?
increased lipids in the plasma can cause the appearance of holes all over the smear
