E2 PATHO WEEK 7 (10.13)

Focuses on specific disorders related to white blood cells.
General theme: Disorders of white blood cells can involve either overproduction or underproduction of cells, similar to red blood cell disorders.

White blood cells (WBCs) are crucial components of the immune system, responsible for fighting infections.
Lifespan:
- Red blood cells: Approximately 120 days.
- White blood cells: Approximately 10 days.
Composition of Blood Cells:
- WBCs constitute about 1% of the total blood cell volume.

White blood cells are divided into two main categories:
- Granulocytes: Include neutrophils, eosinophils, and basophils.
- Agranulocytes: Include lymphocytes (B cells, T cells) and monocytes.

Disorders generally fall into two broad categories:
- Proliferative disorders (overproduction of WBCs)
- Deficient disorders (underproduction of WBCs)

Neutropenia: A condition characterized by low neutrophil counts, which can cause increased susceptibility to infections.
Thrombocytopenia: A condition of decreased platelet count.
Agranulocytosis: The absence of neutrophils; effectively, a severely low or nearly zero count.
- Prefixed ‘A’ indicates absence.

Accelerated removal: Increased destruction of neutrophils, possibly due to rapid apoptosis.
Drug-induced granulocytopenia: Certain medications, such as Clozaril (an antipsychotic), can induce low neutrophil counts.
Cyclic neutropenia: Commonly seen in children, characterized by fluctuating neutrophil counts.
Felty syndrome: A combination disorder associated with rheumatoid arthritis that includes neutropenia and splenomegaly (enlarged spleen).

Caused by Epstein Barr Virus (EBV).
Commonly known as the 'kissing disease' due to its transmission through saliva.
Characteristics of Mononucleosis:
- Once infected, EBV stays dormant in B lymphocytes for life.
- Self-limiting illness: The illness resolves without requiring extensive medical intervention, usually within one to two weeks.
Symptoms:
- Enlarged lymph nodes (especially in axilla and groin).
- Fever, malaise, chills.

Hodgkin's Lymphoma:
- Characterized by the presence of Reed-Sternberg cells.
- Swollen lymph nodes, rarely extranodal (staying within lymph nodes).
- Better prognosis due to limited spread; mainly affects younger adults.
Non-Hodgkin's Lymphoma:
- No Reed-Sternberg cells present.
- Can be extranodal (spreads beyond lymph nodes).
- Generally worse prognosis because it often metastasizes.

Utilizes four stages to classify severity based on the number of lymph nodes involved:
- Stage I: Involvement of a single lymph node.
- Stage II: Involvement of two lymph nodes on the same side of the diaphragm.
- Stage III: Involvement of lymph nodes on both sides of the diaphragm.
- Stage IV: Dissemination of the disease to extralymphatic sites.

Four main types:
1. Acute Lymphocytic Leukemia (ALL)
2. Chronic Lymphocytic Leukemia (CLL)
3. Acute Myelogenous Leukemia (AML)
4. Chronic Myelogenous Leukemia (CML)

Acute: Involves immature cells; often serious and fast-growing.
Chronic: Involves mature cells; generally slower progression.
Cell Origin:
- Myeloid (from bone marrow) or lymphoid (from lymphatic tissues).

Terminal plasma cells: These are mature plasma cells that cannot further divide, and their malignancy indicates multiple myeloma, characterized by bone pain and reabsorption.
M protein: A biomarker used in diagnosing multiple myeloma; its presence indicates the disease.

When dealing with leukemias, focus on the type of cells involved (mature or immature) and their origin (myeloid or lymphoid).
For Hodgkin's disease, confirm the presence or absence of Reed-Sternberg cells.

Normal erythrocyte sedimentation rate for men: 0 to 15 mm/hr.
Hemoglobin levels generally range, with values being critical in assessing health (e.g., not less than 11 g/dL for females).