BLOOD SYSTEM

 

Special note: Chapters 13 and 14 have several factual errors. The following items are corrections for statements made in the text:

·        Beginning at birth, all blood cells originate in the bone marrow

·        Bilirubin is not green. It is a yellow/orange breakdown product of heme. Biliverdin is a breakdown product of heme that is green.

·        Leukocyte normal range is 4,500-11,000/mm³

·        ABO antigens are inherited, ABO antibodies are acquired (not inherited) by 6 months of age after exposure to similar antigens on intestinal flora.

·        When accidentally transfusing incompatible blood such as group a blood to group b recipient, intravascular hemolysis leads to diseminated intravascular coagulation. No agglutination takes place in the blood.

·        Rh positive blood will induce anti-Rh in an Rh negative person about 70% of the time not 100%

·        Immune reactions are any response by your immune system to foreign invasion not just antibodies.

 

FUNCTIONS OF BLOOD—MAINTAIN CONSTANT ENVIRONMENT FOR OTHER LIVING TISSUES

 

TRANSPORT

 

·        RBC’S CARRY O₂ AND CO₂

·        PLASMA CARRIES NUTRIENTS, WASTE, PROTEINS

           

PROTECTION—WBCs

        

·        PHAGOCYTES—NEUTROPHILS, MONOCYTES

·        ANTIBODIES—LYMPHOCYTES

 

COAGULATION

 

·        PLATELETS

·        SPECIFIC PLASMA PROTEINS (SEE FLOW CHART IN TEXT)

              

SPECIFIC BLOOD CELLS

 

ALL BLOOD CELLS ORIGINATE IN THE BONE MARROW FROM STEM CELLS AND DIFFERENTIATE FROM BLAST CELLS TO MATURE CELLS IN THE MARROW (GRANULOCYTES, PLATELETS, AND MONOCYTES, AND B-LYMPHOCYTES) OR THYMUS (PROTHYMOCYTE TO MATURE T-LYMPHOCYTES)

 

ERYTHROCYTES

 

·        BICONCAVE DISKS FILLED WITH HEMOGLOBIN CARRYING O₂ AND CO₂.

·        PRODUCTION STIMULATED BY ERYTHROPOIETIN SECRETED BY THE KIDNEY

 

LEUKOCYTES

           

·        GRANULOCYTES (POLYMORPHONUCLEAR)

 

                        NEUTROPHIL - PHAGOCYTE, NATURAL IMMUNITY AGAINST INFECTIONS

                       

                        EOSINOPHIL - PHAGOCYTE, ALLERGIC REACTION, WORM INFECTIONS

                       

                        BASOPHIL - HEPARIN AND HISTAMINE

                       

·        AGRANULOCYTES (NO GRANULES)

 

                        LYMPHOCYTES - CONTROL IMMUNE RESPONSE, KILL INFECTED OR DISEASED CELLS, PRODUCE ANTIBODIES, E.G., T-CELLS AND B-CELLS

                       

                        MONOCYTES—PHAGOCYTE, PROCESS ANTIGENS FOR T CELL RECOGNITION

 

·        THROMBOCYTES (PLATELETS)

BLOOD GROUPS

 

 

SPECIFIC COMBINATION OF INHERITED ANTIGENS AND ACQUIRED ANTIBODIES

 

 

ABO SYSTEM

 

GROUP     ANTIGEN (ON RBC)    ANTIBODY (PLASMA)

 

   A                               A                                anti-B

 

   B                               B                                 anti-A

 

   AB                      A and B                            no anti-A or anti-B

 

   O                         No A or B                       anti-A, anti-B, anti-A,B

 

 

Rh SYSTEM

 

Rh POSITIVE—Rh ANTIGEN ON RED BLOOD CELLS

 

Rh NEGATIVE—NO Rh ANTIGEN

 

NO anti-Rh ANTIBODY UNLESS EXPOSURE TO INCOMPATIBLE BLOOD:

 

·        TRANSFUSION

·        PREGNANCY

                                                                             

BLOOD SYSTEM PATHOLOGY

 

 

DISEASES OF RED BLOOD CELLS

 

·        ANEMIA - DEFICIENCY OF RBCs OR HEMOGLOBIN

 

·        IRON DEFICIENCY ANEMIA - DEFICIENCY OF IRON (REQUIRED FOR HEMOGLOBIN PRODUCTION) DUE TO:

o       DECREASED IRON IN THE DIET

o       DEMANDS OF PREGNANCY

o       CHRONIC BLOOD LOSS

 

·        APLASTIC ANEMIA - LACK OF BLOOD CELL DEVELOPMENT/FORMATION.  PANCYTOPENIA.

 

·        HEMOLYTIC ANEMIA - EXCESSIVE RBC DESTRUCTION.  ETIOLOGY INCLUDES SPHEROCYTOSIS, ABNORMAL HEMOGLOBIN, E.G., SICKLE CELL

 

o       SICKLE CELL ANEMIA - HEREDITARY; HETEROZYGOUS AND HOMOZYGOUS FORM.  SICKLE-SHAPED RBSs DUE TO DEFECTIVE HEMOGLOBIN, CRYSTALIZES IN RBC AND CLOGS CAPILLARY BEDS

 

 

DISORDERS OF BLOOD CLOTTING

 

 

·        HEMOPHILIA A- CONGENITAL LACK OF ONE BLOOD CLOTTING PROTEIN.  NORMAL THROMBOCYTES; DECREASED FACTOR VIII LEADS TO INCREASED COAGULATION TIME

 

·        PURPURA (PURPLE) - TINY HEMORRHAGES UNDER THE SKIN DUE TO THROMBOCYTOPENIA

DISEASES OF WHITE BLOOD CELLS

 

·        LEUKEMIA - EXCESSIVE INCREASE OF ABNORMAL WBCs

 

·        ACUTE - LARGE NUMBER OF IMMATURE WBCs (BLAST CELLS) IN THE PERIPHERAL BLOOD.

 

·        CHRONIC - LARGE NUMBERS (USUALLY) OF MATURE, DIFFERENTIATED WBCs IN THE PERIPHERAL BLOOD.

 

·        DEVELOP FROM DIFFERENT CELL LINES, e.g., NEUTROPHILS, LYMPHOCYTES, MONOCYTES

 

·        TREATED WITH CHEMOTHERAPY

 

o       RELAPSE - REAPPEARANCE OF LEUKEMIA CELLS

o       REMISSION - SIGNS OF DISEASE DISAPPEAR

                                                                             

LABORATORY TESTS

 

BLEEDING TIME

·        MEASURE TIME FOR PUNCTURE WOUND TO STOP BLEEDING

·        INCREASED TIME WITH PLATELET DISORDERS e.g. thrombocytopenia

     

COAGULATION TIME

·        TIME FOR VENOUS BLOOD TO CLOT

·        IDENTIFIES DEFICIENCY IN SPECIFIC CLOTTING FACTORS

       

COMPLETE BLOOD COUNT (CBC)

·        HEMATOCRIT - % OF RBC PACKED VOLUME OF TOTAL VENOUS BLOOD

·        HEMOGLOBIN—AMOUNT OF HGB IN BLOOD

·        RED BLOOD CELL COUNT

·        RED BLOOD CELL MORPHOLOGY

o       EVALUATE FOR ABNORMAL SHAPE, COLOR OR SIZE

·        WHITE BLOOD CELL COUNT

o       INCREASED WITH INFECTION=LEUKOCYTOSIS

o       EXCESSIVE INCREASE OF ABNORMAL CELLS=LEUKEMIA

·        DIFFERENTIAL

o       EVALUATE % OF CELLS FROM EACH TYPE OF LEUKOCYTE, e.g. 60% NEUTROPHILS

 

PROTHROMBIN TIME

·        ABILITY OF BLOOD TO CLOT

·        MONITOR PATIENTS ON ANTICOAGULANTS FOLLOWING CEREBRAL VASCULAR ACCIDENTS, MYOCARDIAL INFARCTIONS

 

CLINICAL PROCEDURES

·        BLOOD TRANSFUSION (AUTOLOGOUS OR ALLOGENEIC)

·        BONE MARROW BIOPSY-ILIAC CREST USUALLY PUNCTURED

·        BONE MARROW TRANSPLANT

 

                             CHAPTER 14: LYMPHATIC AND IMMUNE SYSTEMS

 

INTRODUCTION

 

            LYMPH:

 

                        CLEAR, WATERY FLUID SURROUNDING CELLS

 

                        DIFFERENT FROM BLOOD

 

                        1.         HAS NO RBCs OR PLATELETS

 

                        2.         CONTAINS LYMPHOCYTES AND MONOCYTES

 

                        3.         HAS LESS PROTEIN THAN BLOOD

 

 

FUNCTIONS OF THE LYMPH SYSTEM       

 

            1.         TRANSPORTS PROTEINS AND FLUIDS THAT HAVE LEAKED OUT OF BLOOD CAPILLARIES

 

            2.         ABSORB LIPIDS FROM THE SMALL INTESTINES

 

            3.         DEFENSE (RELATED TO IMMUNE SYSTEM) AGAINST FOREIGN ORGANISMS, E.G., BACTERIA AND VIRUSES

 

                        A.        LYMPHOCYTES - PRODUCE ANTIBODIES, REGULATE IMMUNE RESPONSES, DESTROY INFECTED OR DISEASED CELLS

 

                        B.        MONOCYTES—PHAGOCYTOSIS, ANTIGEN PROCESSING AND PRESENTATION

 

 

LYMPHATIC SYSTEM

 

            SPLEEN - LOCATED LUQ

 

                        DESTROYS OLD RBCs, FILTERS MICROORGANISMS FROM BLOOD

 

                        IF INJURED AND REMOVED, LIVER, BONE MARROW, AND LYMPH NODES ASSUME FUNCTIONS

 

           

THYMUS GLAND - LOCATED UPPER MEDIASTINUM

 

                        IMPORTANT ROLE IN T LYMPHOCYTE DEVELOPMENT FOR FETUS AND EARLY YEARS

 

                        DECREASES IN SIZE WITH AGE

 

 

IMMUNE SYSTEM

 

            DEFENSE RESPONSE AGAINST FOREIGN ORGANISMS, TUMOR CELLS OR OTHER ANTIGENS

 

            IMMUNITY - ABILITY TO RESIST ORGANISMS AND LARGE TOXINS

 

                        1.         NATURAL

 

                                    A.        GENETIC PREDISPOSITION

 

                                    B.        PHAGOCYTOSIS - NEUTROPHILS ATTRACTED TO BACTERIA, OTHER FOREIGN PARTICLES

 

                                    C.        MACROPHAGES (TISSUE MONOCYTES) - CLEAR AWAY DEAD CELLS AND DEBRIS WHEN INFECTION SUBSIDES

 

                        2.         ACQUIRED

 

                                    A.        ACTIVE - HAVE A DISEASE OR VACCINATION WHICH STIMULATES PRODUCTION OF ANTIBODIES

 

                                    B.        PASSIVE - INJECTION OF "READY MADE" ANTIBODIES TO COUNTERACT SNAKE BITE, ETC. OR PROTECT OR LESSEN THE SEVERITY OF A DISEASE

 

 

 

             

           

 

 

 

 

 

 

 

 

            LYMPH/IMMUNE SYSTEM PATHOLOGY

 

 

AIDS

·        SUPPRESSION OR DEFICIENCY OF IMMUNE RESPONSE DUE TO DESTRUCTION OF CD4 HELPER LYMPHOCYTES INFECTED WITH HIV

·        PREDISPOSES THE PATIENT TO LIFE-THREATENING MALIGNANCIES AND INFECTIONS

·        CURRENT HIGHEST RISK GROUPS ARE TEENAGERS ENGAGED IN UNPROTECTED HETEROSEXUAL INTERCOURSE, YOUNG WOMEN AND THEIR BABIES

·        BEGINNING TO RISE AGAIN IN THE HOMOSEXUAL POPULATION DUE TO MISCONCEPTION THAT THERE IS A CURE

 

 

HYPERSENSITIVITY

·        REACTION RANGES FROM HIVES TO ANAPHYLAXIC SHOCK

·        ALLERGY DUE TO EXAGGERATED IMMUNE RESPONSE

o       BEE STINGS

o       FOODS

 

 

HYPERSPLENISM

·        SPLENOMEGALY

·        OFTEN ASSOCIATED WITH DESTRUCTION OF RED BLOOD CELLS

 

 

LYMPHOMA

·        MALIGNANT TUMOR OF LYMPH NODES/TISSUE

·        THERE ARE MANY FORMS DEPENDING ON CELL TYPE AND DEGREE OF DIFFERENTIATION

 

 

INFECTIOUS MONONUCLEOSIS

·        VIRAL INFECTION LEADS TO LYMPHADENOPATHY

·        REACTIVE LYMPHOCYTES IN BLOOD

·        EBV MOST COMMON CAUSE

 

 

CLINICAL PROCEDURE

 

LYMPHANGIOGRAM - CONTRAST MEDIUM INJECTED INTO LYMPH VESSELS AND X-RAYS TAKEN FOR E.G., DIAGNOSIS AND STAGING OF LYMPHOMA