Hematologic System (Leukocyte and Platelet Emphasis)

Leukocytosis

Normal

Leukocyte count is higher than expected

Normal response to stress (surgery, invading organisms, medications, toxins)

Leukopenia

Never normal

Leukocyte count lower than expected

Can be caused by radiation, anaphylactic shock, and immune diseases

High risk of infection

Granulocytosis (Neutrophilia)

Increase of granulocytes (neutrophils, eosinophils, and basophils)

Evident in the first stage of infection, as neutrophils are the first to show up

Neutropenia

Decrease in circulating neutrophils

Never normal

Product of prolonged, severe infection

What can cause neutropenia?

Starvation and anorexia

Leukemias

Folate and B12 deficiency anemia

Granulocytopenia/Agranulocytosis

No granulocytes

Severe neutropenia

Manifestations of granulocytopenia/agranulocytosis

Severe infection, malaise, ulcers in mouth and colon, fever, tachycardia

Eosinophilia

Increase in eosinophils

Seen in allergies (Type I Hypersensitivity/IgE) and parasitic invasion

Eosinopenia

Decrease in eosinophilia

Basophilia

Increase in basophils

Basopenia

Decrease in number of basophils

Lymphocytosis

Associated with viral infections

Increase in lymphocytes

Lymphocytopenia

Decrease of lymphocytes

Leukemia

Uncontrolled proliferation of malignant leukocytes that overcrowd the bone marrow (pancytopenia)

Manifestations of leukemia

Pallor, fatigue, purpura, fever, anemia, petechiae, ecchymosis

Acute leukemia

Associated with blast cells

Onset is abrupt and rapid

ALL, AML

Chronic leukemia

Slow progression

CLL, CML

What type of leukemia is most common in children?

ALL

Pancytopenia

Crowding of bone marrow by malignant WBCs, creating no room for other cell proliferation

Pathophysiology of leukemia

Lymphadenopathy

Swollen/inflamed lymph nodes

Local lymphadenopathy

Caused by localized infection (Ex. strep throat causes throat lymph inflammation)

General lymphadenopathy

Swelling all over the body

Is associated with the spread of a disease

Malignant lymphomas

Malignant proliferation of lymphocytes that accumulate in lymph nodes, creating tumor masses

Caused by viruses/genetic mutations

Hodgkin Lymphoma

Associated with the presence of Reed-Sternberg (RS) cells

Clinical manifestations for Hodgkin and non-Hodgkin lymphoma

Intermittent fever, anorexia, malaise, weight loss, night sweats, pruritus, thrombocytosis

Non-Hodgkin lymphoma

Lymphoma's not related to RS cells (all other types)

Risk factors for non-Hodgkin lymphoma

Middle-age, male, Caucasian, immune disorders, HIV/AIDS, high fat diet, organ transplant, H. Pylori infection

Manifestations specific to non-Hodgkin lymphoma

Painless swelling of lymph nodes

Back pain, skin rash, itchy skin, fatigue, fever, night sweats, leg swelling

Burkitt lymphoma

Most common type of non-Hodgkin lymphoma

Fast growing tumor on the facial bones

Manifestations of platelet disorders

Petechiae (pinpoint), purpura, mucosal and gingival bleeding, spontaneous bruising

Thrombocytopenia

Decreased platelets

Causes of thrombocytopenia

B12/folate deficiency, medications, chemotherapy, heparin, liver disease, viral illness, genetic syndromes

Immune (idiopathic) thrombocytopenic purpura (ITP)

IgG antibody targets platelets, leading to decreased platelets

Manifestations of Immune Thrombocytopenic Purpura

Petechiae, purpura, major hemorrhages, weight loss, fever, headache

Acute Immune Thrombocytopenic Purpura

Secondary to viral infections

Destruction of immune complexes formed by antigens

Chronic Immune Thrombocytopenic Purpura

Autoantibody mediated destruction against platelet specific antigens

Thrombotic thrombocytopenic purpura (TTP)

Platelets clump together, which leads to decreased platelets

Can cause occlusions of arterioles and capillaries

Essential (primary) thrombocythemia (thrombocytosis)

Increased platelets

Megakaryocytes (precursor of platelets) in the bone marrow are produced in excess

Vitamin K deficiency

Decreased platelets

Vitamin K is necessary for erythropoiesis and clotting

Liver disease

Decreased platelets

Liver produces clotting factors