Microbiology

Conjugation, generalized transduction, specialized transduction, and transformation are known as horizontal gene transfer (HGT), which is when genes, especially those conferring antibiotics resistance, can move between bacteria asexually. These processes …

Sarcoptes scabiei Causes scabies. Presents as itchy bodily areas (e.g., the hands) classically in patients living in close quarters like homeless shelters or group homes. Causes “linear burrows,” although these …

Points about pharm: Nematode infections on USMLE are basically always treated with -bendazoles (i.e., mebendazole, albendazole, etc.). These are microtubule inhibitors. Don’t confuse with -azoles (antifungals). Pyrantel pamoate is another …

Protozoa are unicellular eukaryotes. Amoebas move and feed by extending pseudopods, which are temporary extensions of the cytoplasm. Entamoeba histolytica Acquired as cysts in fresh water. Organisms that are acquired …

Many fungi can be grown on Sabouraud agar, so you can memorize this factoid as a starter. Dermatophytes are fungi that cause skin infections. Trichophyton spp. T. rubrum causes many …

Coronavirus The virus specifically known as SARS-CoV-2, or COVID-19, caused the 2019 global pandemic. SARS stands for Severe Acute Respiratory Syndrome. The pandemic is believed to have started following a …

Alphavirus Causes some obscure brain infection in a farmer called equine encephalitis. Asked maybe once on an old NBME form somewhere. Rubella (aka German measles) Causes fever and head-to-toe maculopapular …

Rhinovirus Most common cause of common cold (i.e., upper respiratory tract infection, with coryza, dry cough, no exudates, and no fever). Nothing else you need to know. Coxsackie A Causes …

Parvovirus B19 Causes Fifth disease = “slapped cheek” facial erythema in Peds. Once child has developed the red cheeks, he/she has immunologically cleared the illness (i.e., if they turn it …

Spirochetes are a group of bacteria with a corkscrew- or question mark-shape that are visualized using a method called dark-field microscopy. You don’t need to know the following for USMLE, …