another q - drgoljan - Printable Version +- USMLE Forum - Largest USMLE Community (https://www.usmleforum.com) +-- Forum: USMLE Forum (https://www.usmleforum.com/forumdisplay.php?fid=1) +--- Forum: Step 1 (https://www.usmleforum.com/forumdisplay.php?fid=2) +--- Thread: another q - drgoljan (/showthread.php?tid=172994) |
another q - drgoljan - ArchivalUser - 03-21-2007 A patient with mild congestive heart failure is treated with high-dose furosemide and diureses 25 pounds of fluid. A complete blood count (CBC) taken before the diuresis shows an RBC count of 4 million/mm3; a CBC taken after diuresis shows a RBC count of 7 million/mm3. Which of the following is the most likely explanation? A. Cyanotic heart disease B. Increased erythropoietin C. Polycythemia vera D. Relative polycythemia E. Renal cell carcinoma 0 - ArchivalUser - 03-21-2007 DDDD 0 - ArchivalUser - 03-21-2007 ddd due to hemoconcentration 0 - ArchivalUser - 03-21-2007 ddd 0 - ArchivalUser - 03-21-2007 D is right example of relative polycythemia, in which there is an increased hematocrit or RBC count without a true increase in the total number of body RBCs. What usually happens in these cases is a significant reduction in plasma volume due to processes such as dehydration, vomiting, diarrhea, or diuresis. Cyanotic heart disease (choice A), via appropriate erythropoietin secretion, can cause secondary absolute polycythemia. Increased erythropoietin (choice B), whether appropriately or inappropriately secreted, can cause secondary absolute polycythemia. Polycythemia vera (choice C) causes primary absolute polycythemia with usually low erythropoietin levels. Renal cell carcinoma (choice E), via inappropriate erythropoietin secretion, can cause secondary absolute polycythemia. 0 - ArchivalUser - 03-22-2007 dddddddd |