This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Bacteria, Subject name: Microbiology
[{'content': 'A Giemsa stain of a thin peripheral blood smear is prepared. Which of the following cannot be diagnosed? \nSelect and explain. \nA. Bartonella henselae, B. Coxiella burnettii, C. Toxoplasma gondii, D. Ehrlichia chaffeensis', 'role': 'user'}, {'content': "Answer: B \nExplanation: Ans. (B) Coxiella burnettii(Ref: Jawetz's Medical Microbiology 27th Ed; Page No-347)A diagnosis of Coxiella burnettii cannot be done using a Giemsa stain of a thin peripheral smear.The diagnosis of Coxiella burnetii is done mainly by serology which shows a rise in the titer of specific antibodies to C. burnettii.Other Options:Toxoplasma gondii: It can invade any nucleated cell and replicate within cytoplasmic vacuoles by a process called endogony (internal budding). The trophozoites stain with Giemsa stain.Bartonella henselae: Invade macrophages and neutrophils which can be seen by Giemsa staining of a peripheral smear.Ehrlichia chaffeensis: They infect circulating leukocytes, erythrocytes and platelets, where they multiply within phagocytic vacuoles, forming clusters known as morulae. They can be seen on peripheral blood smear using Giemsa stain.", 'role': 'assistant'}]