1 Thioglycollate medium is useful for characterizing the microorganisms present in blood cultures. However, interpreting blood culture is challenging since normal microbiota (normal flora) from the skin at the venous blood draw site can contaminate the samples. For this reason, blood is usually taken from each arm and the growth from the blood draw of the right arm is compared to that of the sample from the left arm. Imagine you obtain the following blood sample data: Sampled Site Growth Detected Growth Location in Thioglycollate Medium Right arm Yes Abundant bacterial growth at the top of the tube and bacterial growth isolated at the bottom of the tube Left arm Yes Bacterial growth isolated at the bottom of the tube; no other growth observed Answer the following based on the data: a. Would you conclude normal microbiota were detected? Explain your reasoning. b. Would you conclude the patient has an anaerobic blood infection (bacteremia)? Explain your reasoning.
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This is because there was abundant bacterial growth at the top of the tube, which indicates the presence of normal microbiota. Additionally, bacterial growth isolated at the bottom of the tube further supports the presence of normal microbiota. Show more…
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