CBC Meaning and Interpretation (Part 2)

Dr. Joseph E. Graas, Scientific Director
Dr. Edward Moore, Medical Director

Interpretation:

The CBC is an important part of any work up of an individual for any disease state and addiction is no exception.  It assists in the following important ways:

• Documentation of changes that relate to the severity of the patient’s state of addiction.
• Support of the diagnosis of the drug of abuse.
• Diagnosis of other serious disorders that may or may not be secondary to drug use but which need to be treated.
• Compliance with the standard of care necessary for good medical practice.
• Documentation support for the level of care being rendered.
• Documentation support in the event of legal proceedings.
  

Alcohol:

Alcohol is by far, except for tobacco, the most prevalent drug of abuse and the most easy to see the effects it has on the CBC.  The degree of effects will depend on the stage and severity of the patient’s disease and if the patient has secondary diseases as a result of their alcoholism.  Secondary diseases include cirrhosis, esophageal varicies, ascites, congestive heart failure, pancreatitis, anemia, porphyria, and liver failure among others.

• RBC count, Hct (hematocrit), and Hgb (hemoglobin) – These values are most often LOW, except in the face of dehydration which can occur due to vomiting and acute intoxication when they may be elevated due to the relative loss of the plasma component of the blood. The most important medical emergency to detect and treat is gastrointestinal bleeding.  This occurs with esophageal varicies and stomach ulcerations.  The bleeding may be acute or chronic and can frequently be differentiated by looking at the mean cell volume (MCV) and mean cell hemoglobin (MCH).  Chronically these three values (RBC, Hct, Hgb) can be low due to the direct toxic effects of alcohol on the bone marrow reducing the production of all blood components (pancytopenia).
• WBC count – As mentioned above, due to bone marrow toxicity, there may be a reduction of white blood cells. Alternatively, alcoholics are immuno-suppressed predisposing them to infection in general and the WBC count may be high with a left shift.  Due to loss of the gag reflex when intoxicated the patient may aspirate stomach contents while vomiting causing a chemical pneumonia.  Alcoholics are especially susceptible to gram negative bacterial pneumonia.  When ascites is present the patient can present with a bacterial peritonitis and a possible complication can be ascending bacterial cholangitis that results in hepatitis and liver failure.
• PLT (platelet count) – Low platelet counts are frequently encountered in alcoholism and at times may be critically low (less than 30K) predisposing patients to fatal GI hemorrhage or intracranial bleed. It should be remembered that intoxicated alcoholics commonly fall, have head injuries, and can have withdrawal seizures, all of which can have fatal bleeding consequences.   Low circulating platelets can also be seen when the spleen is enlarged due to portal hypertension.

Part 3 of this article will  appear in the January issue of Toxicology Times