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Updated: Aug 23, 2025

Microscopy-based Assays for High-throughput Screening of Host Factors Involved in Brucella Infection of Hela Cells
Published on: August 5, 2016
Brucella Species Staining as Gram-Positive Rod and Gram-Positive Cocci in Chains
Yigit Baykara1, Carlotta Trapassi1, Gina Miceli1
1Microbiology Laboratory, Department of Pathology and Laboratory Medicine, The Miriam Hospital and Rhode Island Hospital, Providence, Rhode Island.
Abstract:
Two cases of Brucellosis were identified at a hospital in Rhode Island. In both cases, the organisms were isolated from the blood cultures. The bacteria did not appear as the classical textbook description of Brucella spp. as short, Gram-negative rods; instead, Gram-positive rods and Gram-positive cocci in chains were observed. Due to the atypical Gram stain morphology, Brucella spp. were not initially considered as a possible pathogen. Antimicrobial prophylaxes were offered to the technologists who were exposed to the organisms.
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