Fatal Monocytic Ehrlichiosis in Woman, Mexico, 2013

Abstract

Human monocytic ehrlichiosis is a febrile illness caused by Ehrlichia chaffeensis, an intracellular bacterium transmitted by ticks. In Mexico, a case of E. chaffeensis infection in an immunocompetent 31-year-old woman without recognized tick bite was fatal. This diagnosis should be considered for patients with fever, leukopenia, thrombocytopenia, and elevated liver enzyme levels.

Keywords: Ehrlichia chaffeensis; Mexico; bacteria; fatal; human monocytic ehrlichiosis; ticks; vector-borne infections.

Figure 1

Histopathologic appearance of liver biopsy sample from woman with fatal human monocytic ehrlichiosis, Mexico, 2013. A) Necrotic hepatic lesions in a patchy distribution (arrows). Hematoxylin and eosin (H&E) stain; original magnification ×100. B) Macrovesicular steatosis and inflammatory lymphocytic infiltrate. H&E stain; original magnification ×200.

Figure 2

Histopathologic appearance of liver biopsy sample from woman with fatal human monocytic ehrlichiosis, Mexico, 2013. A) Clusters of cells in the liver lobule. Hematoxylin and eosin (H&E) stain; original magnification ×200. B) Immunohistochemical detection of T lymphocytes (CD3). Original magnification ×100. C) Multinucleated cells in parenchyma (circle). H&E stain; original magnification ×400. D) Immunohistochemical detection of macrophages and hyperplasia of Kupffer cells (CD68). Original magnification ×100.