RT Book, Section A1 MA, Lichtman A1 MS, Shafer A1 RE, Felgar A1 N, Wang SR Print(0) ID 1138037481 T1 Blood, Marrow, and Pleural Fluid T2 Lichtman's Atlas of Hematology 2016 YR 2017 FD 2017 PB McGraw-Hill Education PP New York, NY SN 9780071602679 LK accessmedicine.mhmedical.com/content.aspx?aid=1138037481 RD 2024/10/13 AB Graphic Jump LocationView Full Size||Download Slide (.ppt)III.A.001Anaplasmosis (Ehrlichosis). Blood film showing intracellular Anaplasma (arrows). Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum, a genus assigned to the family Rickettsiae. The organism was previously called Ehrlichia phagocytophilum and the disease Ehrlichosis before the names were changed. Human Granulocytic Ehrlichiosis is now called Human Granulocytic Anaplasmosis. The bacterium is transmitted to humans by the bite of a tick. Headache, fever, chills, malaise, and muscle aches are the most common symptoms. Rash is very uncommon. These symptoms occur within 1 to 2 weeks of a tick bite. Anaplasmosis can be suspected based on the clinical presentation, a history of a tick bite (often this is not recalled), a low white blood cell count and low platelet count (present in half the cases), and elevated levels of liver enzymes. Severe clinical presentations may include difficulty breathing, hemorrhage, renal failure or neurological problems. Anaplasmosis can be a serious illness that can be fatal if not treated correctly. The organism is an obligate parasite of neutrophils as shown in this image and undergo their life cycle in leukocytes and platelets. A firm diagnosis is made using the polymerase chain reaction or by immunostaining.