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Date of last update: 10/12/2017.

Forum Name: Hematology Topics

Question: High Red Blood Cells

 lamb265 - Thu Nov 10, 2005 9:26 pm

My son is a 16 year old who has been sick since August. His symptoms include: extreme fatigue, stiffness in neck, fever, dizziness, and headaches. He also has pain in his legs at times. His doctor thinks he possibly has Epstein Barr virus, but she also thinks he may have other things as well. His red blood cells count are 5.45, his hemoglobin is 16.9, his red cell distribution is 11.9 and his lymphocyte is 41.7. His mononuclear is 15.6, his neutrophil is 42.1, his mononuclear absolute is 1.10. His SED rate is 23. His creatinine levels are 1.0. Do you have any idea what is wrong with him? Lyme disease has been ruled out, as has the flu. His doctor told us that possible illnesses are lupus, multiple sclerosis, and Epstein Barr. Any advice would be much appreciated!! Thanks!
 Dr. Tamer Fouad - Thu Jan 26, 2006 1:05 am

User avatar Hello,

I hope your son's condition has improved by now.

Polycythemia is the term used to describe an abnormal increase in the number of RBCs. This condition leads to an increase in Hb, Hct, or RBC in the blood count test.

The evaluation of polycythemia involves first the exclusion of relative polycythemia hemoconcentration that results from decreased plasma volume in conditions such as dehydration.

Secondary polycythemia can arise due to an appropriate bone marrow response to decreased tissue oxygenation, such as: high altitude, cardiopulmonary disorder and increased affinity for oxygen. Secondary polycythemia with normal tissue oxygenation may result from benign renal lesions (renal artery stenosis, renal cysts, hydronephrosis, nephrocalcinosis, transplant rejection, etc.); neoplasms (renal, hepatic, ovarian, adrenal, cerebellar); endocrinopathies (Cushing's syndrome, pheochromocytoma).

Primary polycythemia or polycythemia vera is a myeloproliferative disorder in which the production of RBCs is not controlled by and is independent of erythropoietin. Besides an elevated hematocrit, patients with this disease also have leukocytosis, thrombocytosis, splenomegaly, and a hypercellular bone marrow with trilinear hyperplasia. In early stages, however, a high hematocrit may be the only manifestation.

In the absence of dehydration, a hematocrit greater than 60% is always associated with an increase of RBC mass and is diagnostic of polycythemia. For hematocrit values of 50% to 60%, the diagnosis of polycythemia requires direct measurement of the RBC mass. An RBC mass greater than 32 ml/kg in women and 35 ml/kg body weight in men confirms the diagnosis of polycythemia.

Once the diagnosis of true polycythemia is established, the major differential diagnosis centers between polycythemia vera and secondary polycythemia.

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