Blood🩸

            Blood = Cells + Plasma 

Function of blood 

• Conveying nutrients
• Eliminating waste products
• Caring oxygen and carbon dioxide
• Regulating body temperature
• Maintaining acid base balance 

Cells

• Erythrocytes
• Leukocytes
• Platelets

Composition of blood plasma 

• Water 
• Protein (fibrinogens, globulins, albumins) 
• Other solutes 
• Electrolytes 
• Non protein nitrogen substance (urea, uric acid, creatine, creatinine, (ammonium salts) 
• Nutrients (glucose, lipids, amino acids (
• Blood gasses (oxygen, carbon dioxide, nitrogen) 
• Regulatory substances (hormones, enzymes) 

Red blood cells (erythrocytes) 

• Normal findings
• Adult/elderly

               Male : 4.7 - 6.1

               Female : 4.2 - 5.4

• Children

               Newborn   :4.8-7.1

               2-8 weeks  :4.0-6.0

               2-6 weeks  :3.5-5.5

  6 months - 1 year :3.5-5.2

                 1-6years  :4.0-5.5

                6-18years :4.0-5.5

Abnormal findings

        Increased levels 

• High altitude
• Congential heart disease 
• Polycythemia vera 
• Dehydration/hemoconcentration 
• Cor-pulmonale 
• Pulmonary fibrosis 
• Thalassemia trait 
• Severe COPD 

        Decreased levels 

• Hemorrhage 
• Hemolysis
• Anaemia
• Hemoglobinopathy
• Advanced cancer 
• Bone marrow failure 
• Leukemia/lymphoma 
• Chronic / renal disease 
• Chemotherapy 
• Rheumatoid disease
• Sub acute endocarditis 
• Prosthetic valves
• Multiple myeloma 
• Over hydration 
• Dietary deficiency 

Interfering factors 

• Normal decrease are seen in RBCs during pregnancy because of normal body fluid increase and dilution of the RBCs 
• Person living at high altitudes have increase RBCs 
• Hydration status : dehydration factitiously increases the RBC count, and overhydration decrease the RBC count 
• Drugs that may cause increased RBC levels include erythropoietin and gentamicin 
• Drugs that decreased RBC levels are many including those that decrease marrow production or those that cause hemolysis 

Total WBCs 

• An increased total WBCs count (WBCs >10, 000) usually indicates infection, inflammation, tissue necrosis, or leukaemic neoplasia. Trauma or stress, either emotional or physical may increase the WBC count. 
• A decreased total WBC count occurs in many forms of bone marrow failure 

Platelets 

Causes of thrombocytosis

• Acute bleeding and blood loss
• Alllergic reactions
• Cancer
• Major surgery 
• Pancreatitis
• Iron deficiency
• Vitamin deficiency
• Heart attack 

Causes, thrombocytopenia 

•  Leukemia 
• Some types of anemia 
• Viral infections, such as hepatitis C or HIV 
• Chemotherapy drugs 
• Heavy alcohol consumption

White blood cells (leukocyte) 

Normal findings:Total WBCs

• Adult /child >2years : 5000- 10,000/mm (SI units) 
• Child <2years : 6200-17, 000/mm
• Newborn 9000-30, 000/mm 

Differential count 

Granulocyte:contain specific granules and nonspecific (azurophilic) granule 

• Neutrophils
• Eosinophils
• Basophils 

Agranulocyte: contain only nonspecific (azurophile) granule 

• Monocyte 
• Lymphocyte 

Interfering factors 

• Physical activity and stress may cause an increase in WBC and differential values 
• Pregnancy (final month) and labor may cause increase WBC and differential values
• Patients who have had a splenectomy have a persistent, mild elevation of wbc count. 
• Drug that may cause increase wbc including: 

                Adrenaline, allopurinol, aspirin, chloroform, epinephrine, heparin, quinine, steroids, and triamterene. 

• Drug that may cause decrease wbc including:

                   Antibiotic, anticonvulsants, antihistamine, antimetabolites, antithyroid drug, arsenicals, barbiturates, chemotherapeutic agents, diuretics, and sulfonamides. 

Neutrophil 

• 55-70./. Of leukocyte Or 2500-8000mmcubic
• Diameter 12-15 
• Segmented nucleus 3 -5
• 2type of granules:  

             Specific granules : lysozyme, lactoferein, collagenase 

             Azurophile granule 

• Are product in 7 to 14days and exits in the circulation for only 6 hrs. 
• The primary function of the neutrophil os phagocytosis 

Causes of neutophilia 

• Acute infection
• Acute stress
• Eclampsia 
• Gout
• Myelocyteic leukemia
• Thyroiditis

Causes of neutropenia

• Aplastic anemia 
• Chemotherapy influenza 
• Viral infection
• Addison disease 
• Widespread severe bacterial  infection 

Monocyte

• 2-8./. Of leukocyte Or 100-700 per mm cubic 
• Diameter 12-24 
• Kidney -shape nucleus 
• Belong to agranulocyte 
• Differentiate into macrophage in tissue
• Primary function

        1.  Phagocytosis 

        2.Producing cytokines and                             activating inflammation response 

        3.  Acting as antigen-presenting                       cells 

   

Causes of monocytosis:

• Chronic inflammatory disorders
• Viral infections infectious mononucleosis 
• Tuberculosis 
• Parasitea (malaria) 

   Causes of monocytopenia:

• Aplastic anemia 
• Hairy cell leukemia 
• Drug therapy (Prednisone) 

Eosinophil 

• 1-4./. Of leukocyte Or 50-500mm cubic 
• Diameter 10-15
• Bilobed nucleus
• 2type of granules:

          1.Specific granules

          2.Azurophilic granules 

• Primary function

           1.Defense against parasites 

           2. Modulation of response in                         allergic reaction

            3.Phagocytosis 

Lymphocyte

•      20-40./. Of leukocyte Or 1000-4000 per mm cubic 
• Diameter 6-10
• Spherical nucleus 
• Belong to agranulocytes
• Primary function:create the immune system 

          1. B-lymphocytes - humoral                                                          immunity 

          2.  T- lymphocytes - cellular                                                immune  responses                                      

                     Dr. Mahalakshmi Raghunath