WBR0964
| Author | [[PageAuthor::Mugilan Poongkunran M.B.B.S [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 3 |
| Main Category | MainCategory::Emergency Room |
| Sub Category | SubCategory::Hematology |
| Prompt | [[Prompt::A 50 year old woman comes to the emergency department with complaints of shortness of breath. She has these symptoms for the past one day. Her past history is significant for chronic bronchitis and COPD. She has smoked one pack of cigarette for the past 10 years. She denies alcohol use and use of recreational drugs. She attained menopause at the age of 48 and not on any medications. Her vitals are temperature: 36.7 C, blood pressure: 140/80 mmHg, pulse: 80/min and respirations: 15/min. The patients pulse oximetry shows 96 % on 4-litres of oxygen. Respiratory examination reveals coarse wheeze all over the chest. All other system examinations are normal. Her laboratory values comes as :
Hb : 23 g/dl RBC’s : 6.5 million/cmm WBC’s : 6000/cmm Platelet’s : 300,000/cmm Neutrophils : 58% Eosinophils : 2% Lymphocytes : 33% Monocytes : 7% PT : 13 sec (N 11-15 sec) INR : 1.03 What is the most likely diagnosis in this patient ?]] |
| Answer A | AnswerA::Secondary polycythemia |
| Answer A Explanation | [[AnswerAExp:: Correct : Secondary polycythemia is caused by either natural or artificial increases in the production of erythropoietin that result in an increased production of erythrocytes. This patient has secondary polycythemia due to smoking and lung diseases that result in hypoxia induced erythropoietin production.]] |
| Answer B | AnswerB::Polycythemia vera |
| Answer B Explanation | [[AnswerBExp:: Incorrect : Primary polycythemia, often called polycythemia vera (PCV), polycythemia rubra vera (PRV), or erythremia, occurs when excess red blood cells are produced as a result of an abnormality of the bone marrow. Often, excess white blood cells and platelets are also produced.]] |
| Answer C | AnswerC::Drug induced polycythemia |
| Answer C Explanation | [[AnswerCExp:: Incorrect : Medications and lifestyle activities can result in an increase in red cell mass. These include androgens (eg, testosterone)or anabolic steroids, self-injection of erythropoietin, or transfusion of stored autologous or allogeneic RBCs in order to improve athletic performance.]] |
| Answer D | AnswerD::Relative polycythemia |
| Answer D Explanation | [[AnswerDExp:: Incorrect : An isolated decrease in plasma volume can elevate the hemoglobin, hematocrit, and RBC count. The state of chronically reduced plasma volume with elevated hemoglobin or hematocrit has been called Gaisbock's disease, spurious polycythemia, stress erythrocytosis, apparent polycythemia, and pseudopolycythemia, although many may be examples of smokers' polycythemia.]] |
| Answer E | AnswerE::Chronic myeloid leukemia |
| Answer E Explanation | [[AnswerEExp:: Incorrect : CML presents with increase in WBC’s, platelets’s and RBC’s with altered function resulting in beeding, infections and other complications. This patients lab findings does not suggest that.]] |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::Polycythemia is a condition in which there is a net increase in the total number of red blood cells in the body. Primary polycythemia, often called polycythemia vera (PCV), polycythemia rubra vera (PRV), or erythremia, occurs when excess red blood cells are produced as a result of an abnormality of the bone marrow. Often, excess white blood cells and platelets are also produced. Polycythemia vera is classified as a myeloproliferative disease. Secondary polycythemia is caused by either natural or artificial increases in the production of erythropoietin that result in an increased production of erythrocytes. In secondary polycythemia, there may be 6 to 8 million and occasionally 9 million erythrocytes per cubic millimeter of blood. A type of secondary polycythemia in which the production of erythropoietin increases appropriately is called physiologic polycythemia. Physiologic polycythemia occurs in individuals living at high altitudes, where oxygen availability is less than at sea level. Many athletes train at higher altitudes to take advantage of this effect — a legal form of blood doping. Actual polycythemia sufferers have been known to use their condition as an athletic advantage for greater stamina.
Other causes of secondary polycythemia include smoking, renal or liver tumors, or heart or lung diseases that result in hypoxia. Endocrine abnormalities, prominently including pheochromocytoma and adrenal adenoma with Cushing's syndrome are also secondary causes. Athletes and bodybuilders who abuse anabolic steroids or erythropoietin may develop secondary polycythemia. |
| Approved | Approved::Yes |
| Keyword | WBRKeyword::Polycythemia |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |