A nurse is providing education about leukemia to a group of nursing students. Which statement by a student indicates a correct understanding of the pathophysiology of leukemia?

A) This choice is incorrect because while a complete blood count (CBC) is an important initial screening test for leukemia, it alone is not definitive for diagnosis. A CBC may show abnormal levels of blood cells, prompting further investigation, including a bone marrow biopsy.

B) This choice is incorrect because a urinalysis is not used to diagnose leukemia. It is a test used to evaluate kidney function and detect urinary abnormalities.

C) This choice is incorrect because a chest X-ray is not a definitive diagnostic tool for leukemia. It is primarily used to assess the lungs and chest organs for conditions such as pneumonia or tumors.

D) This choice is correct. A bone marrow biopsy is a definitive diagnostic tool to confirm leukemia. In this procedure, a small sample of bone marrow is taken from the hipbone or breastbone and examined under a microscope to determine if leukemia cells are present. It allows for the identification of abnormal cells in the bone marrow, helping to establish the diagnosis and type of leukemia.

A) This choice is incorrect because impaired bone density would not directly cause ecchymoses on the skin. It might lead to an increased risk of fractures, but not bruising.

B) This choice is correct. Ecchymoses (bruises) of varying sizes with minimal trauma are common in leukemia due to a deficiency of platelets and impaired clotting factors in the blood. Leukemia can lead to decreased platelet production and clotting abnormalities, resulting in easy bleeding and bruising.

C) This choice is incorrect because increased production of platelets would improve clotting abilities and reduce the risk of ecchymoses.

D) This choice is incorrect because elevated levels of red blood cells would not directly cause ecchymoses on the skin. It may lead to other symptoms like increased blood viscosity.