Intracytoplasmic Granulocytic Morulae Counts on Confirmed Cases of Ehrlichiosis/Anaplasmosis in the Northeast

Abstract

Peripheral smears are a useful, cost-effective, and time-effective tool for diagnosing anaplasmosis. In positive cases, diagnostic morulae can be identified with a count of 200 granulocytes.

Hemophagocytic lymphohistiocytosis associated with anaplasmosis

“…However, this is not the standard of care for the diagnosis, as the percentage of granulocytes containing morulae is often low. [2] Moreover, to make peripheral smear more sensitive for the diagnosis most efficacious, it is recommended that at least 200 granulocytes are examined. [2] Definitive diagnosis is based on polymerase chain reaction for A. phagocytophilum as serology testing is often negative during the 1 st week of illness.…”

“…[2] Moreover, to make peripheral smear more sensitive for the diagnosis most efficacious, it is recommended that at least 200 granulocytes are examined. [2] Definitive diagnosis is based on polymerase chain reaction for A. phagocytophilum as serology testing is often negative during the 1 st week of illness. [23] In our patient, no morulae were identified, and this is likely related to his severe neutropenia.…”

“…[123] Initial symptoms typically present 1–2 weeks after being bitten by an infected tick. The clinical presentation is broad ranging from a mild flu-like illness characterized by fever/chills, headaches, myalgias, and malaise to serious and potentially fatal disease including disseminated intravascular coagulopathy if not detected and treated appropriately.…”

“…The clinical presentation is broad ranging from a mild flu-like illness characterized by fever/chills, headaches, myalgias, and malaise to serious and potentially fatal disease including disseminated intravascular coagulopathy if not detected and treated appropriately. [123] We propose that one of the more severe complications may be hemophagocytic lymphohistiocytosis (HLH). HLH is a hyperinflammatory syndrome characterized by unregulated macrophage and T-lymphocyte activation resulting in cytokine overproduction, hemophagocytosis, and tissue destruction.…”

European Network for Neglected Vectors and Vector-Borne Infections COST Action Guidelines: What Is This About and What Is This For?

“…For A. platys, light microscopy presents low sensitivity due to the cyclic character of thrombocytopenia and the low percentage of infected cells (between 0.5% and 5%); therefore, it is recommended to examine between 2,000 and 20,000 platelets (Kontos et al 1991, Chang et al 1996, Brown et al 2006, Eddlestone et al 2007). For the granulocytotropic species, morulae can also be sparsely distributed and difficult to detect, particularly in human samples from which at least 800-1,000 granulocytes should be examined (Aguero-Rosenfeld 2002), although at least one study demonstrates identification in all human cases after examination of only 200 granulocytes (Rand et al 2014). For ruminants, the examination of 400 granulocytes are generally regarded as sufficient to detect infected leucocytes in recent disease, but blood smears from persistently infected animals may give negative results (Stuen et al 2002(Stuen et al , 2006.…”