White blood cells (WBC) provide major host defense mechanisms against invading pathogens through phagocytosis and the immune response. In addition, lymphocytes provide immune surveillance against the development of cancer and are important mediators of disorders of the immune system. White cell disorders are usually the result of overproduction or underproduction of one or more of the WBC series, which include the granulocytes—neutrophils, basophils, and eosinophils—and/or mononuclear cells—lymphocytes and monocytes. Less frequently, WBC disorders result from WBC dysfunction despite normal number of cells. The acuity and severity of these disorders are related to the number of white cells, the subset(s) of WBC involved, their degree of maturity, and their functional capacity.
Initial clinical manifestations of WBC disorders can vary widely but often include signs and symptoms of infection. Disorders of WBC, benign or malignant, frequently also involve abnormalities of the red blood cells (RBCs) and platelets. In these situations, the signs and symptoms of disease at presentation may include those related to anemia (i.e., weakness and easy fatigability) and/or thrombocytopenia (i.e., easy bruisability, mucosal or gastrointestinal bleeding, and hematuria). A careful history and physical examination with evaluation of the peripheral blood, and bone marrow when needed, will establish a diagnosis in many cases.
Aging is not associated with significant changes in the peripheral WBC count or WBC differential (Table 103-1). Therefore, abnormalities in white cell numbers should be evaluated as a probable sign of an active disease process. Most white cell disorders are more common with increased age and the most common WBC disorders in the elderly are neoplastic diseases. Table 103-2 lists the spectrum of white cell disorders encountered in clinical practice. Full descriptions of these processes are available in textbooks of hematology and oncology. This chapter focuses on these disorders as related to geriatric medicine.
Table 103-1 Normal WBC Counts for Adults |Favorite Table|Download (.pdf)
Table 103-1 Normal WBC Counts for Adults
RANGE (× 103/μL)
Table 103-2 Disorders of White Blood Cells |Favorite Table|Download (.pdf)
Table 103-2 Disorders of White Blood Cells
Lack of production
Drug or toxin suppression, which may be temporary or permanent
Ineffective myelopoiesis secondary to B-12 or folate deficiency
Bone marrow failure (aplastic anemia)
Neoplastic causes of decreased WBC (e.g., MDS, acute leukemia, LGL leukemia)
Immune neutropenia secondary to rheumatologic disorders, Felty's syndrome, and lymphoproliferative malignancies
Increased splenic sequestration
Congestive splenomegaly with cirrhosis, Gaucher's disease, etc.
Nonneoplastic increases in WBC
Response to stress (e.g., infection)
Response to drug (e.g., corticosteroids, granulocyte colony-stimulating factor)
Other reactive increases (e.g., inflammation)
Myelodysplastic syndromes (MDS)
Acute myelogenous leukemia (AML)
Acute lymphocytic leukemia (ALL)
Chronic lymphocytic leukemia (CLL)
Chronic myelogenous leukemia (CML)
Large Granular Lymphocytic Leukemia ...