Deficiencies and Disorders

Vitamin B12 deficiency clinical manifestations

fatigue, dyspnea, pallor, glossitis, GI problems, muscle weakness, numbness in hands and feet, prolonged deficiency can result in permanent neurological damage

Folic acid deficiency clinical manifestations

similar to vit B12 but no neurologic problems

folic acid deficiency lab findings

hgb/hct are low, RBCs are macrocytic, ferritin is normal, folate levels low

aplastic anemia lab and diagnostic findings

CBC shows pancytopenia (reduction in RBC, WBCs, and platelets)

aplastic anemia definition

a blood condition in which the bone marrow fails to produce blood cells in sufficient numbers

fibrinolysis

clot formation stops bleeding, removes the clot when it is no longer neeed

primary hemostasis

platelet activation and formation of the platelet plug

secondary hemostasis

activation of the clotting cascade, which makes fibrin reinforce the platelet plug

prothrombin time (PT)

measures the time it takes for plasma to form a clot after adding tissue factor, used to monitor the anticoagulant effect of warfarin

activated partial thromboplastin time (aPPT)

measures the time it takes for plasma to form a clot after an activator reagent is added, used to monitor the anticoagulant effect of unfractionated heparin

what causes a prolonged or extended PT?

vitamin K deficiency, advanced liver disease, warfarin

what causes a prolonged or extended aPPT?

clotting factor deficiencies, severe liver disease, unfractionated heparin sodium

international normalization ratio (INR)

a standardized system of reporting PT, used primarily to monitor and dose warfarin therapy

fibrinogen degradation products (FDPs)

small protein fragments present in the blood after a blood clot is degraded by fibrinolysis

thrombocytosis

an excessive number of circulating platelets (greater than 400,000)

thrombocytopenia

a decrease in the number of circulating platelets (less than 150,000)

petechiae

tiny red, purple, or brown pinpoint spots on the skin, a hallmark sign of low platelet count

purpura

larger flat purple or reddish discolorations on the skin, happen when small blood vessels burst and blood pools underneath

ecchymosis

large flat dark purple/red spots, seen more with clotting factor disorders

clinical manifestations of thrombocytopenia

epistaxis (nosebleed), gum bleeding, hematuria (blood in urine), confusion, severe headache, blurred vision, changes in level of consciousness, petechiae, purpura, ecchymosis, oozing IV site, frank or occult stool, dizziness, tachycardia, hypotension

conditions that impair the production of platelets

chemo and radiation, chronic alcohol use disorder, lack of vit B12 or folic acid, viral and bacterial infections

conditions that accelerate the destruction of platelets

immune thrombocytopenia, drug-induced destruction, infections, disseminated intravascular coagulation, splenomegaly (enlarged spleen)

immune thrombocytopenia

autoimmune disorder where the body produces antibodies against its own platelets, antibody-coated platelets are destroyed by macrophages in the spleen

immune thrombocytopenia clinical manifestations

petechiae and purpura, gingivitis, epistaxis, heavy menstrual bleeding, hematuria

immune thrombocytopenia diagnostic findings

platelet count less than 100,000, hemoglobin normal or low, pT and aPTT normal

disseminated intravascular coagulation (DIC) definition

an acquired disorder in which widespread activation of the coagulation cascade causes small clots to form throughout the microcirculation, consuming platelets and clotting factors, resulting in both thrombosis and bleeding

clinical manifestations of DIC

petechiae, purpura, ecchymosis, bleeding from nose or gums, hematuria, oozing from wound/IV sites, GI bleeding, cyanosis in fingers and toes, dyspnea, renal failure

von Willebrand disease definition

caused by deficient or defective von Willebrand factor, a protein required for platelet adhesion

von Willebrand factor definition

helps platelets stick to the wall of blood vessels at the site of a wound

hemophilia defintion

Inherited bleeding disorder caused by deficiency of a clotting factor, bleeding may not be heavier but it lasts much longer

severe hemophilia defintion

can cause prolonged or spontaneous bleeding, especially into joints, soft tissue, and muscles