Monday, June 26, 2006

White Blood Cell Disorders

Three major components can be recognize in the blood...White blood cells, red blood cells and finally platelets. I have discussed some of the most common causes of red blood disorders..like anemias. White blood cell disorders can be classified in two major categories: 1. Non malignant and 2. Malignant.
Normal range for WBC count is from 5,000 to 10,000. An increase in this normal range is referred as Leukocitosis. Meanwhile a decreased in this normal range is referred as Leukocitopenia.

Non malignant WBC disorders
Non malignant WBC's disorders may arise with number of factors as infection, crush injuries, pregnancy, corticosteroids treatment and other etiological causes. For example in crush injuries the number of neutrophils can arise because involvement of the bone marrow. Cells are present in the marginal zone of the bone marrow and when a crush injury involve the bone marrow those cells in the marginal zone pass to the bloodstream.
Neutrophilia - Refer to an increase of neutrophils. Causes include inflammatory conditions or infection. Also can be seen as a result of a physical stimuli such as heat, cold, surgery, burns, vigorous and extrenuos excercise, nausea and vomiting.
Neutropenia - Decrease of neutrophils. Causes include underproduction of neutrophils due to and injury in the bone marrow, nutritional deficiencies, cyclic neutropenia, hereditary disorders and spleen secuestration. Other transient conditions in children include viral infections. Congenital disorders like Agranulocytosis of Kostmann Type or Meylokathexis(inability to release mature granulocytes in the blood) also can cause neutropenia.

Eosinopenia, Basopenia and Monocytopenia are other conditions in which any of those cells are decreased.

Morpholgical Abnormalities of WBC's

1. Toxic Granulation -Dark granules either fine or heavy are observed in neutrophils or monocytes. Is associated with infectious states, burns, malignant disorders and drug therapy.


2. Dohle Bodies - Inclusion color blue seen in neutrophils and maybe seen in monocytes. Represent aggregates of rough endoplasmic reticulum (RNA). Conditions as infections, burns, drugs and May-Hegglin Disorder.


3. Hypersegmented Neutrophils - Normaly the neutrophil had three to five lobes. More than five lobes is referred as hypersegmented. Deficiencies of Vitamin B12 and Folic acid can cause it. This deficiency also include oval-shaped red blood cells.


4. Pelger Huet Anomaly - Hyposegmented neutrophils. Usually just to lobes that look like a pair of glasses.Is benign conditions since the neutrophils can still working normally.

5. May Hegglin Anomaly - Dohle bodies type of inclusion, abnormal large and poor granulocytes and thrombocytopenia (decrease in platelets) can be seen in this condition. The majority of the patients with this condition have been reported as asymptomatic. Except those with extreme thrombocytopenia in which bleeding tendencies exist.



6. Chediak-Higashi Syndrome - An hereditary disorder. Affect the ability of chemotaxis and kill bacterias. Present large granules deposits that represent abnormal lysosomal development.

Other deficiencies of WBC's include Qualitative disorders in which the WBC can't carry out their normal function.
Later I will discuss the Malignant Disorders since they are more complex and extense.