{"id":214644,"date":"2025-05-15T06:45:22","date_gmt":"2025-05-15T06:45:22","guid":{"rendered":"https:\/\/learnexams.com\/blog\/?p=214644"},"modified":"2025-05-15T06:45:24","modified_gmt":"2025-05-15T06:45:24","slug":"clinical-microbiologist-makes-serial-dilutions-of-several-antimicrobial-agents-in-broth","status":"publish","type":"post","link":"https:\/\/www.learnexams.com\/blog\/2025\/05\/15\/clinical-microbiologist-makes-serial-dilutions-of-several-antimicrobial-agents-in-broth\/","title":{"rendered":"clinical microbiologist makes serial dilutions of several antimicrobial agents in broth"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">clinical microbiologist makes serial dilutions of several antimicrobial agents in broth, and then incubates Irug dilution series with a standard amount of a patient&#8217;s isolated pathogen. What is this microbiologist up?<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">by-Bauer<\/p>\n\n\n\n<p class=\"wp-block-paragraph\">B. antibiogram<br>C. E-test<br>D. MIC<br>E. therapeutic index (TI)<\/p>\n\n\n\n<p class=\"wp-block-paragraph\"><strong><mark style=\"background-color:rgba(0, 0, 0, 0)\" class=\"has-inline-color has-ast-global-color-1-color\">The Correct Answer and Explanation is:<\/mark><\/strong><\/p>\n\n\n\n<p class=\"wp-block-paragraph\">The correct answer is <strong>D. MIC (Minimum Inhibitory Concentration)<\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h3 class=\"wp-block-heading\">Explanation:<\/h3>\n\n\n\n<p class=\"wp-block-paragraph\">The clinical microbiologist is performing a <strong>serial dilution<\/strong> of antimicrobial agents in broth, and then incubating these dilutions with a standard amount of a patient&#8217;s isolated pathogen. This technique is used to find the lowest concentration of an antimicrobial agent that will inhibit visible growth of the microorganism. This lowest concentration is called the <strong>Minimum Inhibitory Concentration (MIC)<\/strong>.<\/p>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">What is MIC?<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>MIC<\/strong> is the smallest concentration of an antibiotic that prevents visible bacterial growth after overnight incubation.<\/li>\n\n\n\n<li>It is a quantitative measure, providing specific numerical data on the sensitivity of the pathogen to the antimicrobial drug.<\/li>\n\n\n\n<li>This allows clinicians to determine the effective dosage of the drug needed to inhibit the pathogen.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">Why serial dilution?<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>Serial dilutions involve preparing a series of tubes or wells with decreasing concentrations of the antimicrobial agent.<\/li>\n\n\n\n<li>Each tube is inoculated with the same amount of bacteria.<\/li>\n\n\n\n<li>After incubation, the tubes are checked for bacterial growth.<\/li>\n\n\n\n<li>The MIC is identified as the lowest drug concentration in which no visible growth occurs.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">How is MIC used clinically?<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li>It helps tailor antibiotic therapy to the patient&#8217;s infection by selecting a drug and dose that will achieve concentrations at or above the MIC in the body.<\/li>\n\n\n\n<li>Knowing the MIC can prevent under-dosing (which may fail to clear infection) or over-dosing (which may cause toxicity).<\/li>\n\n\n\n<li>It is especially important for serious infections or when resistant organisms are suspected.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<h4 class=\"wp-block-heading\">Other options explained:<\/h4>\n\n\n\n<ul class=\"wp-block-list\">\n<li><strong>A. Kirby-Bauer (Disk Diffusion) Test<\/strong>: This involves placing antibiotic-impregnated disks on an agar plate inoculated with bacteria. The zone of inhibition is measured, but this is a qualitative test, not serial dilution.<\/li>\n\n\n\n<li><strong>B. Antibiogram<\/strong>: A profile summarizing the susceptibility of various pathogens to different antibiotics, often compiled from multiple MIC or disk diffusion tests. It is not the procedure described here.<\/li>\n\n\n\n<li><strong>C. E-test<\/strong>: A plastic strip with a gradient of antibiotic concentrations is placed on agar inoculated with bacteria; the MIC is read where bacterial growth intersects the strip. This is similar to MIC but uses an agar method, not broth serial dilution.<\/li>\n\n\n\n<li><strong>E. Therapeutic Index (TI)<\/strong>: This is the ratio of the toxic dose to the therapeutic dose of a drug; it is a pharmacological concept, not related to microbiological dilution testing.<\/li>\n<\/ul>\n\n\n\n<hr class=\"wp-block-separator has-alpha-channel-opacity\"\/>\n\n\n\n<p class=\"wp-block-paragraph\">In summary, the microbiologist is performing a <strong>MIC test<\/strong> by serially diluting antibiotics and incubating with the bacteria to find the minimum concentration that inhibits bacterial growth. This is a critical lab method for guiding effective antimicrobial therapy.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>clinical microbiologist makes serial dilutions of several antimicrobial agents in broth, and then incubates Irug dilution series with a standard amount of a patient&#8217;s isolated pathogen. What is this microbiologist up? by-Bauer B. antibiogramC. E-testD. MICE. therapeutic index (TI) The Correct Answer and Explanation is: The correct answer is D. MIC (Minimum Inhibitory Concentration). Explanation: [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[25],"tags":[],"class_list":["post-214644","post","type-post","status-publish","format-standard","hentry","category-exams-certification"],"_links":{"self":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/214644","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/comments?post=214644"}],"version-history":[{"count":0,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/posts\/214644\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/media?parent=214644"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/categories?post=214644"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.learnexams.com\/blog\/wp-json\/wp\/v2\/tags?post=214644"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}