Pathology 1 - Block 2 - Part 5

davidwurbel7's version from 2016-03-03 19:02

RBC Disorders I

Question Answer
Anemia with MCV less than 80Microcytic Anemia
Anemia with MCV more than 100Macrocytic Anemia
Anemia with MCV between 80 to 100Normocytic Anemia
Iron deficiency anemia, Anemia of Chronic Disease, Thalassemias (β and α), Sideroblastic Anemias can lead to this anemiaMicrocytic Anemia
The most common anemia world wideIron Deficiency Anemia
Dietary iron that is readily absorbed by the body. Iron is in the ferrous stateHeme-Iron
Dietary iron that is not readily absorbed by the body. Iron is in the ferric stateNon Heme-Iron
Dietary lack, Impaired absorption, Increased requirements and Chronic blood loss are reasons for deficiencyIron Deficiency Anemia
Peptic ulcer, hemorrhoids, carcinoma stomach/colon, aspirin, ulcerative colitis, esophageal varices, hookworm infestation are reasons for thisChronic Blood Loss
Lab values Hb: reduced, Hematocrit: reduced, Red cell indices: MCV, MCH, MCHC are decreased. Peripheral smear. Red cells: microcytic hypochromic, anisocytosis (variation in size), poikilocytosis (variation in shape): pencil cellsIron Deficiency Anemia
If a bone marrow aspirate is done, hyperplastic marrow. Microcytic maturation of the erythroid series. Loss of stainable iron in macrophages (gold standard) which is demonstrated by Prussian blue stainIron Deficiency Anemia
The stain used for bone marrow to test for ironPrussian Blue
Biochemical tests Serum iron concentration: low; The TIBC (total iron binding capacity): increased; Percentage saturation (percentage of transferrin molecules that are bound by iron (normal: 33%)): decreased; Serum ferritin: decreasedIron Deficiency Anemia
The clinical features that can be seen include fatigue, light headedness, palpitation, pounding in the ears, decreased work performance (school children), menstrual abnormalities, sometimes angina pectoris (severe anemia), pica (craving for unusual things. example: clay), pallor, glositis (smooth red tongue), angular cheilitis, ‘burning sensation’ of tongue, koilonychia (spoon shaped concavity of nails), growth impaired (children), lowered immunity, hair loss, restless legsIron Deficiency Anemia
Triad of features include microcytic hypochromic anemia; atrophic glossitis and esophageal websPlummer-Vinson Syndrome
This is associated with chronic disease infections or non-infectious inflammatory disorders, certain types of malignancyAnemia of Chronic Disease (ACD)
Pathogenesis of this condition is caused by IL-1 and TNF, IFN gamma which are brought on by chronic infection/neoplasia. These cytokines stimulate ‘hepcidin’ (an acute phase reactant) synthesis in liver and inhibits release of iron from the storage pool (prevents release of iron to transferrin)Anemia of Chronic Disease
An acute phase reactant that is synthesized in the liver and inhibits release of iron from the storage pool (prevents release of iron to transferrin)Hepcidin
Lab diagnostics anemia, normocytic normochromic (microcytic, hypochromic may be seen later in the disease); MCV: normal to reduced; serum iron is reduced; serum ferritin is increased or normal; TIBC: is decreased/normal. In the bone marrow - normal usually macrophage iron is normal or increasedAnemia of Chronic Disease
Results from an increase in the rate of red cell destruction. Premature destruction of red cells may be due to intrinsic abnormality of rbc (red cell membrane, Hb molecule, & enzymes) or extrinsic abnormality of rbc (mostly acquired either immune or non-immune)Hemolytic Anemia
RBCs being destroyed in the blood vesselsIntravascular Hemolysis
RBCs being destroyed in the spleenExtravascular Hemolysis (Intrasplenic Hemolysis)
After a RBC is destroyed, free hemoglobin is first picked up by this moleculeHaptoglobin
After a RBC is destroyed, free hemoglobin is picked up by this molecule after the haptoblobin molecules have been exhaustedHemopexin
An unstable product of hemoglobin break down which then converts to ferrihemeMethemoglobin
Hemopexin is unable to bind hemoglobin directly. Hemogloblin must first spontaneously oxidize to Methemoglobin and then to this which combines with HemopexinFerriheme
If both haptoglobin and hemopexin are exhausted, hemogloblin is excreted in the urine showing up asHemoglobinuria
If both haptoglobin and hemopexin are exhausted, hemoglobin can be taken up by epithelial cells in the bladder and stored as Hemosiderin. These cells are then exfoliated into the urine and show up asHemosiderinuria
This stain is used to positively identify reticulocytesSupravital Stain
Deficient / or lack of synthesis of alpha (α) chainAlpha Thalassemia
Deficient / or lack of synthesis of beta (β) chainBeta (β0) Talassemia
Diminished synthesis of structurally normal β globin chains, along with unimpaired synthesis of α chains. reduced but detectable amount of β chainBeta (β+) thalassemia
Lab values include Hb: severe anemia, RBC Indices: low MCV, Peripheral blood smear: ansiopoikilocytosis, microcytic, hypochromic, target cells, fragmented red cells, nucleated red cells. Reticulocyte count: increased Biochemical: bilirubin, iron studies. Hb Electrophoresis: HBA2, HBF, are increased - low or absent HBA. Bone marrow expansion, and bone changesBeta Thalassemia Major
Condition clinical features include marked pallor, jaundice, requires blood transfusion, growth retardation, splenomegaly by 3 years, skeletal system abnormalities, gall stones, infections. Treatment includes blood transfusion and splenectomy may helpBeta Thalassemia Major
Condition diagnosis made by chance, anemia is mild but becomes evident during pregnancy. Mild microcytic anemia, decreased Hb, decreased MCV, and normal serum ferritin levels. Hb electrophoresis: mild decrease in HbA, and increase in HBF, and HBA2Beta Thalassemia Minor
Deletion of all four α globin chains most severe form, South East Asia. In fetus, excess gamma chains form tetramers (Hb Barts). Hb Barts has very high affinity for oxygen, but no oxygen delivered to tissue. Decreased MCV, increased rbc count. fetal distress occur in 3rd trimester intrauterine death fetus: severe anemia (Hb 3 to 8 gm%), pallor, generalized edema, massive hepatosplenomegaly , signs of cardiac failure if alive. Mother frequently has toxemia of pregnancy (hypertension, fluid retention with or without proteinuria), polyhydroamnios or oligohydroamniosHydrops fetalis
The hemoglobin produced by the fetus in Hydrops fetalisHb Barts
Group of disorders of varying etiology. characterized by pathologic iron deposits in erythroblast mitochondria. Iron glutted mitochondria is seen as a ringSideroblastic Anemia
This condition is acquired primary - myelodysplastic syndrome (MDS) and secondary due to chronic alcoholism, drugs (isoniazid: INH), pyridoxine (vitamin B6) deficiency or lead poisoningSideroblastic Anemia
The pathogenesis of this condition is a defect in heme synthesis within mitochondria. Iron is brought into mitochondria to form heme. If protoporphyrin is absent, iron would remain within mitochondria. These iron laden mitochondria appear as a ring around the nucleus of developing red cells (precursors) in bone marrow - “ringed sideroblasts” . This leads to increased iron storesSideroblastic Anemia
Lab Findings for this condition include Peripheral blood smear - may be normocytic, macrocytic, or even microcytic; red cells referred to as dimorphic (normocytic + microcytic). Pappenheimer bodies (Iron inclusion). MCV: usually low. Bone Marrow - erythroid hyperplasia, abnormal forms “ring sideroblasts” (15 to 100%), raised hemosiderin. Special test: expression of mitochondrial ferritin. Biochemical - decreased TIBC, serum iron is increased, serum ferittin levels increased, urine porphyrin profile may reveal erythropoietic porphyria. serum lead/alcohol. Clinical Features: supportive measures, withdrawal of alcohol, withdrawal of drug/ treat with pyridoxineSideroblastic Anemia

RBC Disorders II

Question Answer
Due to impairment of DNA synthesis that leads to ineffective hematopoiesis. two major types of anemia are pernicious anemia and folate deficiencyMegaloblastic Anemia
Vitamin B12 deficiency can be in people that follow this strict for dietVegan
Competitive parasitic infection that can compete with the host for B12 with this parasiteFish Tapeworm
Condition that occurs in the older age group (5th to 8th) decade of life. Most common cause for vitamin B12 deficiency. Familial pattern. Older than 60, more in women, Scandinavia. Pathogenesis include chronic atrophic gastritis or achlorhydria (reduced gastric acid). Antibodies to intrinsic factorPernicious Anemia
Lab values Hb: reduced. Peripheral blood smear: Red cells: macrocytic change (typically oval; ovalocytes), and Howell-Jolly bodies. White blood cells: hypersegmented neutrophils are seen. Red cell indices: increased MCV (› 100)Megaloblastic Anemia
Inclusion bodies seen with megaloblastic anemiaHowell-Jolly Body
Bone marrow biopsy shows increased cellularity, megaloblastic change seen in all erythroid precursors and nucleus retains finely distributed chromatin, no chromatin clumping. Cytoplasm shows regular hemoglobinization (N/C asynchrony) granulocytic series: giant metamyelocytes, platelets: abnormally large, multilobation of nucleiMegaloblastic Anemia
Biochem lab values - serum bilirubin: mild increase, serum cobalamin: decreased levels, serum Homocysteine: increased (not specific), Methylmalonic acid: increased in serum and urine, antibodies to IF: present in most cases, Urine: increased methylmalonic acidVitamin B12 Deficiency
Clinical features include anemia (lemon tint), mild icterus, glossitis (smooth, sore (beefy) due to loss of papillaeMegaloblastic Anemia
Clinical features include autoimmune gastritis: atrophy of fundic glands, and intestinal metaplasia with a risk for cancerPernicious Anemia
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Question Answer
Pathogenesis for this condition include three factors: 1) reduced erythropoietin, 2) suppression of erythropoeisis, & 3) shortened red cell survival of these, reduction in erythropoietin (EPO) is a major causeAnemia of Renal Failure
Blood picture for this condition include usually normocytic normochromic, but macrocytes are also seen, burr cells on blood smear. Platelet count is either normal or slightly increased, but platelet function may be severely impaired, resulting in defective hemostasis, characterized by prolonged bleeding time defects in platelet adhesion, secretion, and aggregation (related to uremia). Treatment: recombinant EPOAnemia of Renal Failure
If the now corrected reticulocyte count is more than 3% it indicates thisGood Marrow Response
A good marrow response the most important cause being thisPeripheral RBC Destruction
If the now corrected reticulocyte count is less than 3% it indicates thisPoor Marrow Response
A poor marrow response the most important cause being thisAplastic Anemia
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Question Answer
Simultaneous presence of anemia, leukopenia and thrombocytopeniaPancytopenia
Etiologies of this condition could be extrinsic immune mediated suppression of marrow progenitors and intrinsic abnormality of stem cellsAplastic Anemia
Lab diagnosis - pancytopenia, absolute neutrophil count is reduced, relative lymphocytosis, sometimes. Bone marrow - marked reduction in cellularity (less than 25%) increase fatty marrowAplastic Anemia
Clinical features of this condition the patient will present with pallor, weakness, easy bruising and infectionsAplastic Anemia