Lab Diagnostics
Parasites & Tropical Diseases
Antibiotics
TB & COVID
100
This phase of laboratory testing accounts for the majority of errors and includes issues such as incorrect labeling, improper sample collection, or delays in transport to the lab.
What is the pre-testing phase?
100
This protozoan parasite, transmitted by the feces of triatomine “kissing bugs,” is the causative agent of Chagas disease
What is Trypanosoma cruzi?
100
This class of antibiotics, which includes erythromycin and azithromycin, inhibits bacterial protein synthesis and is considered bacteriostatic rather than bactericidal.
What are macrolides?
100
This tuberculosis drug can cause optic neuritis, leading to red–green color blindness.
What is ethambutol?
200
A stool Gram stain is not routinely ordered to diagnose infectious diarrhea because this(these) finding(s) is always present and makes the test unhelpful
What are numerous normal gram-positive and gram-negative bacteria (normal intestinal flora)?
200
This antiprotozoal drug is activated in anaerobic organisms and is commonly used to treat giardiasis, trichomoniasis, and amoebiasis, but causes a disulfiram-like reaction with alcohol.
What is metronidazole?
200
This class of antibiotics mimic D-ala D-ala, bind to transpeptidase and prevent cross-linking of peptidoglycan in the cell wall.
What are β-lactam antibiotics?
200
This symptom, occurring in up to 83–99% of patients, is the most common clinical manifestation of COVID-19.
What is fever/chills?
300
This pathognomonic viral inclusion, seen in enlarged cells with a clear halo, is characteristic of cytomegalovirus infection
hat is an “owl’s eye” inclusion?
300
This systemic antifungal binds ergosterol in the fungal cell membrane, forming pores that disrupt membrane integrity and can cause significant nephrotoxicity.
What is amphotericin B?
300
This antibiotic treats serious Gram-positive infections, including MRSA, by binding the D-ala-D-ala terminus of cell wall precursors.
What is vancomycin?
300
This first-line tuberculosis drug inhibits synthesis of mycolic acid and is activated by the bacterial enzyme KatG.
What is isoniazid?
400
This serologic finding is considered the gold standard for diagnosing active infection when comparing acute and convalescent samples.
What is a four-fold rise in IgG titer?
400
In chronic Chagas disease, this cardiac conduction abnormality typically appears first and is more common than its left-sided counterpart
What is a right bundle branch block?
400
This class of antibiotics is bactericidal and disrupts DNA replication by inhibiting bacterial DNA gyrase and topoisomerase IV.
What are fluoroquinolones?
400
Unlike most RNA viruses, coronaviruses can maintain a very large ~30 kb genome because they possess this unique enzymatic activity in nsp14.
What is 3′→5′ exoribonuclease proofreading activity?
500
This common bacterial resistance mechanism uses membrane proteins to actively pump antibiotics out of the cell, lowering intracellular drug concentration.
What is an efflux pump?
500
This Plasmodium species causes the most severe malaria because it infects red blood cells of all ages, often shows multiple ring forms per cell, and causes capillary blockage by making infected RBCs adhere to vascular endothelium.
What is Plasmodium falciparum?
500
This protein synthesis inhibitor is commonly used for anaerobic infections and is notorious for causing pseudomembranous colitis.
What is clindamycin?
500
In tuberculosis, this host immune mediator released by activated T cells is critical for controlling intracellular bacteria by activating macrophages and maintaining granuloma integrity.
What is interferon-gamma (IFN-γ)?
