Increased WBC (leukocytosis, 10,000/ul): Infections, Tissue Necrosis, crush injuries, AMI, Inflammation Disorders, leukemia, cancer, surgery, stress, DKA, Meds (Epinephrine, corticosteroids, ...), eclampsia, uremia, Collagen Vascular Disorders
Decreased WBC (leukopenia, <4000/ul): Overwhelming infection/sepsis, Viral Infections, HIV - AIDS, Immunosuppression, Bone Marrow suppression - infiltration - disease, Anemias (Aplastic, Pernicious,...), Meds (chemotherapy, antibiotics, ...)

Increased Neutrophils (segmented, segs, polys, PMNs - >65-70%; bands - >1-5%): Acute Infection (bacterial sepsis > viral, parasitic, mycotic, spirochete), Inflammatory Disorder (RA, Vasculitis, Rheumatic fever, thryroiditis), Physiologic (Stress - physical or mental, pregnant, newborn, exercise), Tissue Destruction/Necrosis (MI, burns, gangrene, trauma, cancer), Hematologic (leukemia, Hodgkin's, myeloproliferative disorders, acute hemorrhage, splenectomy, hemolysis), Meds (Epinephrine, Corticosteroids), DKA, uremia, eclampsia
Decreased Neutrophils (neutropenia, <50%): Overwhelming Bacterial Infection, sepsis, Viral Infection, (hepatitis, influenza, infectious mononucleosis, measles, chicken pox...), Typhoid, Paratyphoid, Rickettsial disease, Hematologic (Aplastic Anemia, Megaloblastic Anemia, iron deficiency anemia, myelofibrosis, bone marrow infiltration, acute lymphoblastic leukemia, splenomegaly [hypersplenism, congestion, Gauchers, lymphoma]), Meds (Chloramphenicol, chemotherapy, Chlorpromazine, Rifampin, antibiotics), liver pathology, ?immunosuppression, Autoimmune disorder

Increased Lymphocytes (> 40-50 %): Viral Infection (infectious mononucleosis, hepatitis, influenza, measles, mumps, CMV, herpes, ...), Bacterial Infection, (chronic, TB, 2° Syphilis, Typhoid, Toxoplasmosis), Hematologic (Iymphocytic leukemia, multiple myeloma, Hodgkin's Disease), Inflammatory Disorders (Ulcerative Colitis, ITP), Endocrine (Adrenal hypotunction, Thyroid hyperfunction), Leukemias (hairy cell, acute lymphatic...)
Decreased Lymphocytes (< 15-20 %): Cushing Disease/Syndrome, Corticosteroid intake, chemotherapy, radiation therapy, Epinephrine, Immunosuppression/deficiency (AIDS, meds), SLE, cancer, renal failure, alcoholism

Increased Monocytes (> 8%): Infections (infectious mononucleosis, TB, SBE, malaria, viruses, parasites, rickettsial), Monocytic leukemia, Hodgkins Disease, inflammation, cancer

Increased Eosinophils (> 4%): Allergic Disorders (hay fever, asthma, drug reactions, serum sickness), Parasitic Diseases (Schistosomiasis, Strongyloidiasis, Trichinosis, Echinococcosis, Cysticerosis...), Fungal Infections, Cancer (colon, ovarian, testes, lung, Hodgkin's, lymphoma, CML), Skin Pathology (Eczema, Psoriasis, Urticaria, Dermatitis), Collagen Vascular Disorders (SLE, Polyarteritis Nodosa, Vasculitis), Ulcerative Colitis, Crohn's, Hypereosinophilic syndromes (Leofflers Syndrome, chronic eosinophilic pneumonia...)

Increased Basophils (> 1-2%): Leukemia (Basophilic, Granulocytic, Monocytic), Hodgkin's Disease, myeloproliferative disorders, chronic allergic reactions, Sarcoid, Infections (Syphilis, TB, rickettsial, SBE), inflammation

Increased Platelets (thrombocytosis, > 400 x 10^3/mm^3 or 400 x 10^9/l): Cancer, splenectomy, acute infection, chronic granulocytic or myelogenous leukemia, chronic inflammation (RA, CUC...), acute hemorrhage, myeloproliferative disorders, polycythemia vera
Decreased Platelets (thrombocytopenia, < 100-150 x 10^3/mm^3 or 100-150 10^9/l): Sepsis, DIC, S/P multiple blood transfusions with significant hemorrhage, Immunologic (ITP, post transfusion, HIV - AIDS, Infectious Mononucleosis, SLE, Collagen Vascular Diseases, Sarcoid, Meds [Lasix, Quinine, Quinidine, Sulfonamides, Thiazides, Gold Salts]), Cancer - ?bone marrow infiltration - suppression (CA, acute leukemia, lymphoma, CLL, post chemo, post RT, multiple myeloma), hypersplenism, HUS, TTP, Meds (chemo, Heparin, ASA, Penicillin), Hematologic (Aplastic Anemia, Pernicious Anemia, Hemolytic Anemia, myelofibrosis), liver disease, heart failure, heart valve (consumption), significant hemangiomas, Genetic (Bernard Soulier, Wiskott Aldrich, Gauchers, Fanconi, May Hegglin, Felty's), alcohol

Increased Hgb/Hct (>16-18 g/dL or > 46-52%): Polythycemia Vera (Primary or Secondary - Altitude), CHF, COPD, Hemoconcentration (dehydration, burns, diarrhea, increased insensible H20 losses), transfusions, congenital heart disease, Erythropoietin secreting tumors (renal cell, ovarian, hepatoma ...)
Decreased Hgb/Hct (< 11-13.5 g/dL or < 33-39.5%): Hemorrhage (acute [post op, ectopic pregnancy, AAA, trauma...], chronic, GI [UGI: PUD, gastritis, varices via portal hypertension, Mallory Weiss tears, esophagitis, CA-tumors, polyps, lymphoma, aortoenteric fistula, Meckel's diverticulum; - LGI: angiodysplasia, CA-polyps, diverticula, colitis-proctitis-IBD, bacterial enterocolitis, hemorrhoids -fissures- fistulas, mesenteric ischemia...], GU), Anemias (Hemoglobinopathies [Sickle Cell, Thalassemia, S, C], Nutritional Deficiencies [Iron, Folate, Vitamin B12], Pernicious - Vitamin B12 Intrinsic Factor problems, Aplastic), Bone Marrow Failure -Infiltration - Suppression, Hemolysis (transfusion reaction, artificial heart valve, Hereditary Spherocytosis, Elliptocytosis, Ovalocytosis, Glycolytic Enzyme Deficiencies [G6PD deficiency], PNH, microangiopathic [DIC, TTP, HUS], splenomegaly, antibody production [allo, auto- warm/ cold), cancer, leukemia, lymphoma, Meds (chemo, antibiotics, sulfonamides...), pregnant, cirrhosis, liver disease, renal failure, fluid overload, chronic disease (SBE, SLE, RA, TB, Crohns... ), excess phlebotomy (ICU), hypothyroidism, hypoadrenalism, CHF

Increased MCV ( mean corpuscular volume, macrocytic anemia, MCV > 100 fL): folate deficiency, Vitamin B12 (cobalamin) def., intrinsic factor def. (gastrectomy), pernicious anemia, ileal resection or bypass, intestinal stasis, malabsorption (Crohn's, tropical sprue, blind loop syndrome...), hypothyroidism, alcoholism, liver disease, Meds (Methotrexate, AZT, chemo-DNA synthesis inhibitors), reticulocytosis (mild), pregnant (mild), myelodysplastic syndrome
Decreased MCV (microcytic, < 80 fL): iron deficiency*, sideroblastic anemia* (ETOH, lsoniazid, cancers), hemoglobinopathies (Thalassemia*), lead, chronic disease; *also MCHC

Increased Reticulocyte Count (retics - immature nonnucleated RBCs, >1.5%, parallels bone marrow activity): hemolytic anemia, acute post hemorrhage (3-4 days), anemia Rx (iron, transfusion, folate, Vitamin B12), pregnant
Decreased Reticulocyte Count (< 0.5%): inadequate bone marrow production (aplastic anemia, sepsis, chemotherapy/RT..), bone marrow failure, renal failure, chronic disease, hypothyroidism

Peripheral Blood Smear Review: Spherocytes - Hereditary Spherocytosis, hemolytic anemias (autoimmune), ETOH; Target Cells - Hemoglobinopathies, Thalassemia, post splenectomy: Tear Drop Cells - myeloproliferative disorders, Thalassemias, megaloblastic anemia; Schistocytes (fragmented) - microangiopathic hemolytic anemias (immune, DIC, TTP, HUS, hemangiomas, eclampsia...), prosthetic heart valves; Howell Jolly Bodies - post splenectomy, hemolytic anemias, megaloblastic anemia; Heinz Bodies - hemolytic anemia, hemoglobinopathies, oxidation, G6PD deficiency, post splenectomy; Stippling - lead poisoning, hemolysis, Thalassemia; Hypochromatic Microcytic - iron deficiency anemia, sideroblastic anemia, Thalassemia, anemia of chronic disease

Increased Prothrombin Time (PT, > 13-14 seconds): Coumadin (Warfarin), Vitamin K Deficiency, DIC, Factor Deficiency (VII, X, V, II - Prothrombin, I - Fibrinogen), Hepatocellular- Biliary Disease (carcinoma, biliary obstruction, cholestasis, cirrhosis/ alcoholism, hepatitis), excessive heparinization, dysfibrinogenemia, ASA, beta lactam antibiotics

Increased Partial Thromboplastin Time (PTT, > 35-40 seconds): Heparin, DIC, Factor Deficiency (VIII - Hemophilia A, IX - Hemophilia B/Christmas Disease, XII, XI, X, V, II, I -Hypofibrinogenemia), von Willebrand's Disease, Hepatic-Biliary Disease (cirrhosis, biliary obstruction...), Vitamin K deficiency, circulating anticoagulants (lupus anticoagulant)

Increased Bleeding Time (> 9-10 minutes): platelet dysfunction, ASA, DIC, thrombocytopenia, von Willebrand's disease, uremia, NSAIDs, Ticlopidine, severe liver disease, myeloproliferative diseases (leukemia...), Bernard-Soulier, Glanzmann's, alcohol intoxication

Increased Thrombin Time (> 18 seconds): Heparin, DIC, thrombolytics (tPA, streptokinase, urokinase), fibrinolysis, severe liver disease, multiple myeloma, afibrinogenemia, hypofibrinogenemia, dysfibrinogenemia, uremia

Increased Fibrinogen (>400 mg/dl, >4.0 g/l): acute MI, pregnancy, acute infection or inflammation(acute phase reactant), oral contraceptives
Decreased Fibrinogen (< 200 mg/dl, < 2.0 g/l): DIC, significant liver disease, fibrinolysis, afibrinogenemia, hypofibrinogenemia, eclampsia, end stage cancer

+D Dimers (from plasmin action on crosslinked fibrin): DIC, PE, tPA, DVT, pregnant, CA

+FSPs, FDPs (sensitive to fibrinogenolysis and fibrinolysis, > 10 ug/ml): DIC, thrombolytics, PE, thrombosis (venous), cancer, S/P cardiopulmonary bypass surgery, late obstetrical problems, significant liver disease

Increased Erythrocyte Sedimentation Rate, ESR (> 15-20 mm/hr): Infections, Inflammation (acute and chronic), cancer, collagen vascular disease (SLE, RA...), Ulcerative Colitis, Crohns, glomerulonephritis, thyroid abnormalities, multiple myeloma, lymphoma, tissue necrosis, acute MI, SBE (Note - This test is very sensitive with low specificity.)

DIC Differential (Disseminated Intravascular Coagulation): Infections (gram negative > gram positive sepsis, bacterial, viral, fungal, rickettsial [Rocky Mountain Spotted Fever], protozoal), Obstetric Complications (retained dead fetus, amniotic fluid embolism, placental abruption, eclampsia, septic abortion), Cancer (adenocarcinoma, acute leukemia - promyelocytic,...), Surgical (trauma, fat emboli, burns, prostate), Shock, DKA, tissue necrosis, pancreatitis, heat stroke, severe liver disease, transfusion reaction, head injury

Hypercoaguable State: Antithrombin III def., Protein C or S def., lupus anticoagulant, anticardiolipin Ab, Factor V Leiden, oral contraceptives, pregnancy, obesity, immobility, myeloproliferative diseases, cancer, major post-op, CHF, age, H/0-MI, CVA, PE, smoker, COPD