Micro High Yield Flashcards
Toxins that increase cAMP
ETEC Heat-Labile toxin, Bacillus Anthracis Edema factor, Cholera toxin, and pertussus toxin
Inflammatory component of gram negative LPS
Lipid A Note: Lipoteichoic acid induces TNFa and IL-1 from G+
Novobiocin–
Sensitive: Staph epidermidis
Resistant: Staph saprophyticus
Quellung Reaction
Strep Pneumo Note: Strep pneumo capsule swells when bound by Ab (specific); Lancet shaped diplococci
Bacitracin:
Sensitive: Strep Pyogenes
Resistant: Strep agalactiae
Endocarditis following GI/GU procedures
Enterococcus Note: Can grow in bile and 6.5% NaCl
Gram Positive Rods with Metachromatic (blue and red) granules
Corynebacterium diptheriae Note: Black colonies on cystine-tellurite agar; ADP Ribosulates EF-2; ELEK test for toxin
tetanospasmin block GABA and glycine release from?
Renshaw cells in the spinal cord Note: trismus (lockjaw), Risus Sardonicus, and Opisthonotos (eyes locked)
Serpentine chains of G+ rods
Bacillus anthracis Note: spore forming; edema factor inc cAMP; + lethal toxin
Only G+ that produces LPS
Listeria Note: Tumbling motility and can grow at 4 degrees celcius (cold enrichment)
Acid fast+ and G+, causes pulmonary infections
Nocardia Note: weakly acid fast (carbolfuschin); TX with sulfonamides
Oxidase+, G- that grows at 42 degrees
Camplyobacter Note: Comma shaped, undercooked chicken; Guillane-Barre and Reactive Arthritis
Oral abscess or facial abscess (draining through sinus tract) with yellow sulfur granules
Actinomyces Note: Branched G+ bacteria; TX with penecillin
Asthma and CF pts at risk for this infection causing bronchiectasis and Eosinophilia
Allergic Bronchopulmonary Aspergillosis (ABPA) Note: Can lead to bronchiectasis
Bacteria that causes Lymptocytic Leukocytosis
Bordetella pertussis Note: Produces lymphocytosis promoting factor that blocks lymphocytes from leaving blood for lymph node
Grows in both bile and 6.5% NaCl (G+ coccus)
Enterococcus
Only bacteria with a polypeptide capsule
Bacillus anthracis Note: D-glutamate; Cutaneous- ulcer with black eschar
Gonorrhea immune evasion
Rapid Ag variation of Pilus proteins Note: also often intracellular in neutrophils (culture negative UTI)
Chlamydia/Gonorrhea Tx regimen
Ceftriaxone + Azithromycin/doxycycline
G- coccobacillus causing otitus media, bronchitis, conjunctivitis
Nontypable Haemophilus influenze Note: No capsular Ag
Pneumonia with Hyponatremia, watery diarrhea, heachahe and GI pain
Legionella Note: can cause SIADH and decreased tubular reabsorption; Charcoal Yeast Extract
Key E coli virulence factor for: UTI? Pneumonia? Neonatal Meningitis? Sepsis?
UTI- Fimbrae/P-pili; Shock-LPS
Pneumonia/Meningitis- K Capsule
E. Coli strain that does not ferment sorbitol or produce glucuronidase
EHEC Note: O157:H7, Shiga-like/Verotoxin causes microthrombi to form on toxin-damaged endothelium–>HUS
Woolsorter’s disease
Bacillus anthracis Note: inhalation of SPORES from contaiminated wool; flu-like with rapid progression to fever, hemorrhage, mediastinitis and shock
Two toxins that inhibit EF-2
Diptheria toxin and Pseudomonas Exotoxin A
Gardener with skin ulcer on arm and nodules traced up the arm; CIGAR-shaped budding yeast
Sporothrix Schenkii Note: Ascending Lymphangitis
Optochin-
Sensitive: Strep Pneumo (bile solube);
Resistant: viridans strep (bile insoluble) Note: Strep pneumo also has a capsule and is bile soluble (lysed by bile)
Bacteria grown in culture w/ Staph aureus (which provides Factor V/NAD+
Haemophilus influenza Note: otherwise grown on chocolate agar–>NAD/Factor V and Hemitin/Factor X
Bloody diarrhea w/ bacteria that invades @ M cells in Peyer’s patch and spreads cell to cell (not hematogenous spread)
Shigella Note: does not produde H2S; Invasion of intestinal mucosa is the most important virulence factor
Diarrhea after eating raw oysters
Vibrio vulnificus
Appendicitis-like mesenteric adenitis from a puppy
Yersinia enterocolitica Note: bloody diarrhea with puppy may also be campylobacter
Flu, Jaundice, and Photophobia after contact with animal urine in Hawaii
Leptospira interrogans Note: Can cause Weil disease–>severe jaundice with azotemia, anemia, fever and hemorrhage
Screen and confirm tests for Syphilis
VDRL/RPR screen; FTA-ABS confirms Note: Can also try to visualize the spirochete on Darkfield microscopy; CSF for VDRL/RPR for tertiary
Bacteria that causes Kaposi like purpura after cat scratch
Bartonella (Bacillary angiomatosis)
Deer hides/pelts in Arkansas/Missouri, Rabbits
Francisella tularensis
Osteomyelitis/cellulitis after a dog/cat bite
Pasteurella multocida
Dermacentor tick spreads these bacteria
Ricketsia and Francisella
Monocytes with morulae
Erlichiosis Note: blue, berry like inclusions
Granulocytes with morulae
Anaplasmosis Note: Ixodes tick with Borrelia and Babesia
Infectious form of Chlamydia? Intracellular form?
Elemenatary is infectious, Reticulate is intracellular Note: Cannot make own ATP; Visualized on Giemsa stain
Atypical pneumonia with bird exposure
Chlamydophila psittaci Note: C. pneumoniae also causes atypical pneumonia
Cold agglutinin Immune hemolytic anemia
Mycoplasma, infectious mononucleosis
Dimorphic fungus intracellular in Macrophages
Histoplasmosis Note: Immunocomprimised patients can have hepatosplenomegaly and ulcerated tongue lesions
Spaghetti and Meatball appearence, damage melanocytes
Malassezia furfur Note: Tinea Versicolor, spot that does not tan
Yeast that branch at 45deg? 90deg?
45-Aspergillus; 90-Mucor/Rhizopus
Germ Tubes at 37 deg
Candida
Key immune cell to prevent Candida superficial vs systemic
Superficial–T lymphocyte; Systemic-Neutrophils
Pt in North Carolina with rash that starts at wrists
Rocky Mountain Spotted Fever/Rickettsia Note: Starts are wrists and ankles then spreads to the palms/soles and trunk; Dermacentor Tick
This is the site of cryptococcus initial infections
Lungs (not nasopharynx) Note: inhalation of yeast, pidgeon droppings
Most specific test for Cryptococcus
Latex Agglutination Note: detects polysaccharide capsular Ag; India Ink is also characteristic but a shittier test, Mucicarmine stains red
Fungus that causes frontal lobe abscesses after penetrating cribiform plate in Ketoacidotic diabetic or leukemia pt
Mucor/Rhizopus Note: Black, necrotic eschar on face; Branch at 90, nonseptate;
Fungal infection that can be treated with Potassium Iodide
Sporothrix Schenkii Note: Also with itraconazole–>Rose Gardener’s disease
Liver abscess w/ anchovy paste exudate and flask shaped ulcer
Entamoeba histolytica Note: Metronidazole/Iodoquinol; RBC in entamoeba
AIDS pt with amoeba infection in brain causing focal deficits, dementia and coma; no lake exposure
Ancanthamoeba
IgE mechanisms to block/kill parasites
Antibody-Dependent Cellular Cytotoxicity via Eosinophils Note: binds FcER1 on eosinophils causing Major Basic Protein release
Green nasal discharge after jumping in a lake
Naeglaria fowleri Note: enters cribiform plate causing rapidly fatal meningoencephalitis w/ amoeba in CSF
African Sleeping Sickness/Trypanosoma brucei TX
Suramin (Blood) and Melarsoprol (CNS) Note: Winterbottom’s sign–>swollen lymph nodes on back of the neck
Chorioretinitis, Hydrocephalus, and intracranial calcifications
Toxoplasma gondii Note: tachyzoite on biopsy; Sulfadiazine and Pyrimethamine
Hemolytic anemia with “Maltese cross” in RBC on smear
Babesia Note: Ixodes tick with Lyme/Borrelia and Anaplasma–>Atovaquone+azithromycin
Trophozoites with RBC in cytoplasm or Cysts w/ 4 nuclei
Entamoeba histolytica Note: Metronidazole/Iodoquinol; Entamoeba is the only amoeba that phagocytizes RBC
Chagas Tx
Nifurtimox Note: mega colon, megaesophagus, dilated cardiomyopathy
Macrophage with Amastigotes
Leishmania donovani Note: Sandfly bite; spiking fever, hepatomegaly, pancytopenia
TX for Leishmania
Sodium Stibogluconate
TX for anal pruritis/Scotch tape test +
Mebendazole or Pyrantel Pamoate Note: Enterobius vermincularis/Pinworm (nematode)
Filiform larvae in soil penetrate skin after rhabdiform larve lost in stool
Strongyloides Note: Can have autoinfection if rhabdiform becomes filiform in the gut
TX for Strongyloides
Ivermectin or Albendazole
Black skin nodules and blindness
Onchocerca volvulus Note: “River” blindness due to RXN to bacteria in onchocerca (Wolbachia)
TX for Riverblindness
Ivermectin
Elephantiasis organism and TX
Wucheria bancrofti; Diethycarbamazine Note: takes 9mo-1year; blocks lymphatics
Scabes (skin lesions on hand) TX
Permethrin or Ivermectin
Forms cysts in liver than require ethanol injection prior to surgery to prevent anaphylaxis
Echinococcus Note: Hydatid cyst; Ingestion of eggs from dog feces; TX with albendazole; sheep Dog is definitive host
TX for Taenia solium
Praziquantel Note: Albendazole for neurocystacercosis–>ingestion of eggs (not cysts in pork–>tapeworm)
Organism that causes Squamous Cell carcinoma of bladder and can lead to bilateral hydronephrosis
Schistosoma Note: Cercariae leave snails and penetrate skin; Egypt and China; Praziquantel
Cholangiocarcinoma and pigment gallstone association
Clonorchis sinensis Note: China, undercooked fish, liver fluke, Praziquantel
Pt with brain cysts and Seizures
Neurocystacercosis
Parasite causing Microcytic Anemia? Macrocytic?
Microcytic: Hookworm (Necator americanus/Ancylostoma
Macrocytic: Diphyllobothrium latum Note: larvae penetrate skin (Bendazole or pyrantel pamoate)
Undercooked fish (Praziquantel)
Parasites treated with Ivermectin
Strongyloides and Onchocerca
Undercooked crabmeat
Paragonimus Westernmanii
Inflammation of the liver capsule by Neisseria gonorrhea
Fitz-Hugh Curtis Syndrome Note: due to ascention of the gonorrhea, can also cause salpingitis/PID leading to infertility
Comma shaped bacteria that grows in alkaline medium
Vibrio cholera
Rabies binds to this recepter to cause infection
Nicotinic Ach Receptor Note: Replicates initially in muscle and connective tissue–>Retrograde transport in axons to CNS
Bartonella TX
Azithromycin Note: G- but very fastidious (difficult to grow and test for susceptability)
Live Vaccines
VZV, Polio, MMR Note: small pox and yellow fever; Live polio vaccine allows production of gut IgA against polio (unlike killed)
DNA virus with reverse transcriptase
HepB Note: Circular partially dsDNA; can cause HCC via integration into host genome (no cirrhosis first)
RNA viruses that do not replicate in the cytoplasm
influenza and HIV
Killed Vaccines
Rabies, Influenze, HAV
Herpes virus envelope are from?
nuclear membrane
Pts immune to HepB will not have what Ab if vaccinated
Anti-HBcAg
Recombinant vaccines
HepB (HbsAg) and HPV
Pt has punch out lesions in the esophagus
HSV-1 Note: CMV also causes esophageal lesions–>linear ulcers
Most common cause of acute hemorrhagic cystitis in kids
Adenovirus Note: dsDNA linear, also causes pink eye, febrile pharyngitis, and pneumonia
Temporal lobe encephalitis with acute mood, memory, and behavioral changes and Cowdry Type A Inclusions
HSV-1
JC viurs genome type
dsDNA circular (Polyomavirus) Note: similar to BK virus that infects the kidney in transplant patients
Pts with infectious mononucleosis are at risk for rupture of what organ
spleen Note: hepatosplenomegaly with fever, pharyngitis, and lymphadenopathy (poster cervical especially)
EBV receptor
CD21 Note: Infects B cells and blood smear shows atypical CD8+ T cells (Downey cells)
Virus that can cause high fevers/febrile seizures followed by a diffuse macular rash on the body after several days
Roseola Note: HHV6; Febrile SEIZURES key for differentiating from other Rashes of Childhood
Where is VZV latent
Dorsal root or trigeminal ganglia Note: Single dermatome, transmitted by respiratory secretions
Characteristic test for genital herpes
Tzanck test Note: detects multinuclear giant cells in opened skin vesicle
Immature Squamous cell with Dense pink cytoplasm and a perinuclear halo
Koilocyte Note: HPV, Nucleus may be enlarged with undulating membrane
dsRNA with linear, segmented genome
Reovirus (rotavirus) Note: Most common cause of fatal diarrhea in children, more common in winter
Hepatitis with high mortality in pregant women
Hep E Note: Hepevirus->ssRNA+ linear
4 virus in Paramyxovirus (ssRNA- linear)
Parainfluenza, RSV, Measles, Mumps
Key TX for RSV
Ribavirin Note: Inhibits duplication of viral genome via inhibiting IMP dehydrogenase; #1 cause of respiratory death in infants, causes fusion of respiratory epithelial cells and giant cells via Fusion (F) protein
Rabies virus genome
Rhabdovirus–ssRNA (-) linear
Hepatitis B vaccination protects against what additional virus
HepD/Delta agent Note: HepD must use HBsAg to replicate/spread
Picornaviruses that cause meningitis
Echovirus, Poliovirus, Coxsackievirus
Main virulence factor of rhinovirus (common cold)
> 100 serotypes
Segmented viruses
Orthomyxovirus, reovirus, bunyavirus, hantavirus
black vomit, high fever, jaundice
Yellow fever virus Note: SS+RNA
Post Auricular lymphadenopathy in a child with a fine rash on body that started at head and moved down
Rubella Note: Deafness, PDA, blindness, blueberry muffin rash in neonate
mAb that blocks F protein in RSV
Palivizumab Note: prevents fusion of respiratory epithelial cells to for multinucleated cells
Child with white spots with erythematous background on buccal mucosa with maculopapular rash
Measles Note: Koplik Spots; Vitamin A used to prevent severe exfoliation
Pt is delirious with hypersalivation and laryngeal spasms
Rabies
What determines the incubation period length in rabies
Distance of inoculation site from CNS Note: Bites near head and neck progress rapidly
Postexposure TX of rabies
Wound cleansing + Active and Passive immunization Note: rabies immune globulin injected
What causes HepC immune evasion?
RNA-dependent-RNA-Polymerase has No 3’-5’ exonuclease proofreading function Note: hypervariable envelope glycoprotein
Positive serology in the window period of HepB
Anti-HBc IgM
What HepB Ag indicates active infection/high transmissability
HBeAg/HBV DNA Note: Also indicated likelihood of a mother passing to a child–>95% chance with high HBeAg
Progression of Ag&Ab in HepB
SECES Note: SE Ag, CES Ab
Pol gene in HIV genome contains:
Reverse Transcriptase, aspartate Protease, Integrase Note: raltegravir blocks integrase, which prevents production of HIV mRNA by host enzymes
Homozygous mutation of what surface molecule provides HIV immunity
CCR5 Note: bound by gp120; Blocked with Maraviroc
HIV Screen and Confirmatory Tests
Screen: ELISA; Confirm: Western Blot (+ for 3 proteins) Note: AIDS when CD4
Child develps progressive dementia, ataxia, myoclonus, and visual problems; had a rash on body about 6 years ago; Oligoclonal bands in CSF
Subacture Sclerosing Panencephalitis Note: Occurs about 6 years after having measles
Vesicular lesion on trunk with lesions of different ages in child
VZV Chickenpox Note: “Dew on a Rose”
How can newborns of HIV mothers be falsely positive for HIV?
IgG against HIV cross the placenta Note: ELISA and Western Blot test for HIV Ab, confirm exposure to actual virus w/ HIV PCR
During the latent phase of HIV, why is blood level of HIV low?
Replication in the lymph nodes
Tongue ulcer and hepatosplenomegaly in AIDS pt
Histoplasma capsulatum Note: No pulmonary symptoms; Oval yeast IN macrophages
White material on lateral tongue that can’t be scraped off, HIV
Hairy Leukoplakia/EBV
Visual Impairment in HIV pt with cotton wool spots on fundoscopic exam
CMV Retinitis Note: TX with ganciclovir/Foscarnet (Foscarnet can cause seizures–chelates Ca2+ and Mg2+)
Spongiform Encephalopathy with rapid dementia and ataxia
Prions/Creutzfedt-Jakob
Characteristic finding in HIV CNS invasion
Microglial nodules with Multinucleated Microglial cells
Primary CNS Lymphoma in AIDS associated with what
EBV Note: B lymphocytes, can be focal or multiple periventricular ring enhancing lesions
Pt with AIDS has purple papules diffuse across skin (give 2)
Bacillary Angiomatosis- Bartonella–Neutrophil infiltrate
Kaposi Sarcoma- HHV-8-Lymphocyte infiltrate
Key normal flora bacterium of the vagina
Lactobacillus
Pseudoappendicitis associated with daycare
Yersinia enterocolitica
Gas gangrene and watery diarrhea organism
Clostridium perfringens Note: spore forming G+ rod, Alpha toxin=lecithinase
Osteomyelitis most common
Staph Aureus
Osteomyelitis in Diabetic/IV drug user
Pseudomonas or Serratia Note: Serratia ferments lactose
Signs you went from cystitis/UTI to acute pyelonephritis
WBC Casts, Fever, flank pain, CVA tenderness Note: UTI has WBC in urine but NOT casts
Urease positive UTI
Proteus, Klebsiella Note: E. coli is urease negative; staph saprophyticus is nitrite negative
Newborn with PDA, cataracts, and deafness, what infection
Rubella
Seizures and hearing loss in a newborn
CMV Note: Often with blueberry muffin rash and petechial rash
Meningitis with a petechial rash
Neisseria meningitidis Note: LOS mediated (meningococcus has LOS instead of LPS); Purpura Fulminans
Chronic Diarrhea and recurrent infections in a newborn
HIV Note: If HIV negative and infections are viral, bacterial, and fungal, think SCID
Congenital Syphilis findings
Notched/Hutchinson teeth, saber shins, saddle nose, short maxilla, CN8 deafness Note: often results in still birth or hydrops fetalis
Possible cause of infertility in women with HX of PID
Failure to TX both Gonorrhea and Chlamydia in co-infected pt Note: Look out for Infertility Questions where the woman had PID and was only tx with Ceftriaxone OR doxycycline/Azithromycin
Pt with purulent cervical discharge and adhesion from peritoneum to liver
Fitz-Hugh Curtis Syndrome
Child with sickle cell at risk for what infection(s)
Strep pneumo, Haemophilus and Salmonella osteomyelitis Note: Autosplenectomy in SCD makes susceptable to encapsulated microbes
In osteomyelitis, what is the devitalization of bone called
sequestra
In osteomyelitis, reactive bone formation in the periosteum
Involucrum
Muscle pain with calcified cyst in skeletal muscle, splinter hemorrhages in nails and periorbital edema, Eosinophilia
Trichinella spiralis Note: Due to eating undercooked pork; Tx with albendazole, larvae encyst in striated muscle and often have dystrophic calcification
Does the rash in Measles or Rubella become confluent
Measles
Erythematous rash that begins on the cheeks then extends to trunk and proximal extremities
Parvovirus B19–Erythema infectosum Note: Arthritis in adults
When are children with VZV/Chickenpox infectious
1 week BEFORE the rash appears Note: Macules, vesicles and pustules all present at the same time
How must you treat onychomycosis/tinea unguium
Oral agents–terbinafine or itraconazole
What technique can be used to help identify tinea versicolor
Wood’s Lamp Note: Fungus derived acids inhibit tyrosinase (hypopigmentation) –> does not tan
Newborn with “cradle cap” seborrheic dermatitis, what tx
shampoo (selenium sulfide, zinc pyrithione Note: Malassezia furfur
Kid plays in sandbox with cat/dog, Serpiginous tunnels in skin with intense pruritis and eosinophilia
Cutaneous Larval Migrans Note: Ancylostoma –> dog/cat hookworm, larvae migrate in skin; TX with Ivermectin
Intensely pruritis lesion inbetween fingers
Scarptes scabiei Note: Intense pruritis caused by the EGGS; TX with permethrin cream
Bedbug organism
Cimex lectularius Note: feed on human blood, active just before dawn, intensely pruritic
Hepatitus C is associated with what dermatologic condition
Lichen Planus Note: Polygonal Purple Planar papules and plaques + Wickham’s Striae + Sawtooth Dermal-Epidermal junction
Infections associated with Erythema Multiforme
Mycoplasma and HSV Note: Targetoid rashes on palms soles and extensor surfaces
Infections associated with Erythema Nodosum
Coccidioidomycosis, Histoplasma, TB, Strep pharyngitis, Yersinia Enterocolitica
Hepatitis B has a prodrome including what type of rash
Uticaria Note: Type 3 Hypersensitivity –> Serum Sickness-like prodrome
Pt with sinopulmonary infection also has eczema and thrombocytopenia
Wiscott Aldrich Syndrome Note: X linked progressive deletion of B and T cells; Dec IgM and G; Inc Ig A and E
Hepatitis B is associated with what Vasculitis
Polyarteritis nodosa Note: typically effects the renal and mesenteric arteries–>Transmural inflammation w/ fibrinoid necrosis
What is the major virulence factor for Strep pyogenes
M Protein Note: Inhibits phagocytosis and complement activation, cytotoxic for neutrophils, and mediates adhesion
TB growth in parallel chains/sepentine cords signifies:
Cord Factor + Note: Cord factor is TB’s key virulence factor and is needed for infection
Toxin produced by Listeria to exit phagosome in macrophage
Listerolysin O Note: facultatice intracellular G+ rod; tumbling motility and growth at 4 deg C
Child with a Pink upper body and Cyanotic lower body had what infection transmitted from the mother
Rubella Note: Rubella associated with PDA, which causes differential cyanosis when the shunt reverses
Most common cause of myocarditis and pericarditis
Coxsackie virus Note: also dilated cardiomyopathy (via myocarditis)
Metachromatic granules in a clustered Gram +
Corynebacterium diptheriae Note: Red and Blue granules, toxin inhibits EF-2 (protein synthesis), ELEK test for toxin
Most common infection transmitted by blood transfusion (currently)
CMV Note: In the past HepC was the big one, but now PCR makes that rare; CMV in donor lymphocytes
Most common extrapulmonary site for Miliary TB
Kidney
Inspiratory stridor and brassy cough in a child
Parainfluenza virus/Croup Note: Steeple sign on X-ray, Brassy=barking
Transplant pt or AIDS pt with pneumonia; Histology shows enlarged macrophages w/ inclusions and surrounded by halo
CMV
Staccato (choppy) cough in a newborn with pneumonia 2 weeks after birth
Chlamydia trachomatis
Dairy Farmer/Veternarian has atypical pneumonia
Coxiella burnetii Note: associated with livestock birthing process
Yellow sputum in pt w/ pneumonia 5 days after viral pneumonia
Staph Aureus
Hypersensitivity Pneumonitis is a restrictive lung disease caused by thermophilic actinomyces; What type of Hypersensitivity
Type III hypersensitivity (IgG mediated) Note: Farmer’s Lung; Silo Filler’s Disease is due to inhalation of N2O from silo’s, also causes restrictive disease
Inhalation of bacterial endotoxin in cotton, linen, and hemp cause what disease that improves over the weekend
Byssinosis Note: Workers feel better over the weekend then dyspnea reoccurs during the week
Pt presents with diarrhea 3 hours after a picnic, what do you culture and what do you give for TX
Culture: Food – especially if mayo containing
TX: Supportive
Foamy, PAS+ macrophages in the GI lamina propria
Tropheryma whippelii
“Healthy” vs Infective Chronic carrier of HepB
Infective is HBeAg/HBV DNA positive Note: Both are HBsAg positive
Fever, Jaundice, and RUQ pain
Ascending Cholangitis (charcots triad) Note: If septic shock and AMS–> Reynold’s Pentad
How is clonorchis contracted
encysted larvae in undercooked fish Note: high risk of cholangiocarcinoma; Chinese liver fluke
Responsible for the green pigment of sputum in lobar pneumonia
Myeloperoxidase Note: from neutrofils
Epididymitis/Orchitis/Prostatitis bacteria by age
35: E. coli or Pseudomonas Note: In epididymitis, elevation of the scrotum Relieves the pain (Prehn’s sign)
Red Inclusions in cervical metastatic squamous cells
Reticulate bodies of Chlamydia trachomatis
Yeast with germ tubes
Candida
TX for oral thrush
Nystatin Note: Same mechanism as amphotericin B; swish and swallow because not absorbed
Classic Galactosemia is associated with what infection in neonate
E. coli Sepsis Note: Deficiency of Galactose-1-P Uridyltransferase
previously healthy person in the Southwest US who develops rapid septic shock and/or severe pulmonary disease
Yersinia pestis Note: Prarie dogs and rats; Plague; (Coccidioides would not cause disease this severe in immunocompetant person)
Thayer Martin contains Vancomycin, Polymyxin/Colistin (g-) and nystatin, used to isolate what
Neisseria meningitidis and gonorrhea Note: Used for carrier screening from pharyngeal samples
Obligate Intracellular bacteria
Rickettsia and Chlamydia Note: Cannot produce ATP
In toxic shock syndrome, what is released by the TH1 cell?
INF-gamma Note: That induces cytokine release from the APC
Specialized transduction involves what type of virus
Lysogenic bacteriophage Note: General transduction is lytic phage; Specialized: Shiga-like, Botulinum, Cholera, Diptheria toxins
Strep viridans endocarditis mediated by binding what on valves
Bind fibrin-platelet aggregates Note: produces dextrans from sucrose to facilitate binding
Palor around the mouth with a sandpaper type rash in a kid
Scarlet Fever Note: Step Pyogenes, toxin mediated
Prevention of Tetanus in newborns
Vaccination of the mother (IgA/G in breastmilk/placenta) Note: Or on a large scale, vaccinate young adults
Mechanism of Gram neg resistance to penecillin G and Vanco
Outer membrane layer inhibits entry
Neisseria meningitidis contains what instead of LPS
Lipo-oligosaccharide (LOS) Note: Levels of LOS in plasma corrolated with severity of disease, essentially the same as LPS
Rifampin monotherapy is used for prophylaxis in contacts for what
Meningococcus (N. meningitidis) or Haemophilus Note: never used alone for TB
Gray vaginal discharge, fishy smell, clue cells
Gardnerella vaginalis “Bacterial vaginosis” Note: Tx w/ metronidazole or clindamycin; KOH “whiff test” worsens fishy smell
Treatment for all vector borne bacterial diseases
Doxycycline
Painless ulcers on genitals with painful, ulcerated inguinal nodes
Lymphogranuloma venereum Note: Chlamydia trachomatis serotypes L1, L2, and L3
TX for Toxoplasmosis
Sulfadiazine + pyramethamine +/- leucovorin
Green vaginal discharge with itching and burning
Trichomonas vaginalis Note: Metronidazole for pt and partner
Used to prevent severe exfoliative dermatitis in measles infection
Vitamin A
Organisms for AIDS Encephalitis vs Meningitis
Enceph: JC virus; Meningitis: Cryptococcus
Pneumonia in an AIDS pt with CD4 count >200
Strep Pneumoniae Note: presents as normal community acquired lobar streph pneumo
Nucleoside Reverse Transciptase inhibitor used in pregnancy
Zidovudine
C. diff toxin causes pseudomembranous colitis via what action
Actin Depolymerization Note: Damages cytoskeletal integrity
Gastric Biopsy shows a positive urease test (becomes more basic when urea added to biopsy
Helicobacter pylori infection Note: H. pylori converts urea to CO2 and NH3–>NH3 increases pH, changing the color of the indicator
Measured in serum to test for Anaphylaxis
Tryptase
Main manifestation of Parvovirus in adults
Arthralgia Note: symmetric in PIPs, wrists, knees, and ankles
G- oxidase +, lactose non-fermenter
Pseudomonas
Reassortment can only occur in what type of virus
Segmented Virus
How does Silicosis (pneumoconiosis) increase TB risk
Silica impairs phagolysosome formation by macrophages
Bacteria that release toxins that lyse cell membranes
Clostridium perfringens and Step pyogenese (streptolysin O)
Flu-like symptoms after onset of Syphilis tx
Jarish-Herxheimer reaction Note: killed bacteria release pyrogens
Person presents w/ erythemia migrans after camping and fever/hemolytic anemia
Borrelia/Lyme Disease AND Babesiosis Note: Babesia is parasite that causes hemolytic anemia and fever; Maltese cross on blood smear
Cephalosporins active against Pseudomonas
Ceftazidime (3rd) and cefepime (4th) Note: Ceftaroline (5th) is active against MRSA
Antibiotic class contraindicated in Myasthenia gravis–>neuromusclular blockade
Aminoglycosides Note: Drug inactivated via acetylation, phosphorylation, and adenylation
Used to treat strep infections in pts allergic to penecillin
Macrolides Note: Prolong QT, acute cholestatic hepatitis, increase serum concentration of theophyllines and anticoagulants
Abx that can cause kernicterus in newborns
Sulfonamides Note: displace bilirubin from albumin
Needed to convert isoniazid to active form
Catalase-peroxidase Note: Chemically similar to Pyridoxine/vitamin B6; Neurotoxicity (dec w/ B6 supp), hepatotoxicity, Drug-Lupus
TB drug effective in the acidic pH of Phagolysosome
Pyrazinamide Note: works in macrophages where intracellular TB is
TX for Schistosomiasis, Clonorchis, and Taenia solium
Praziquantel Note: Increases permability to Ca, causing muscle paralysis
Pts w/ late compliment (C5-9) deficiency are susceptable to
Neisseria meningitidis infections
Resistance to aminoglycosides is via:
conjugation of the drug at the bacteria surface Note: acetylation, adenylation, phosphorylation
Abx that prolong QT
Macrolides and fluoroquinolones
Tetracycline derivative that is effective against MRSA
Tigecycline
Main side effect of acyclovir? Ganciclovir?
Acyclovir can crystallize in urine–>Nephrotoxic
Ganciclovir causes myelosuppresion
What two drugs are associated w/ Fanconi Syndrome
Tenofovir and expired Tetracyclines Note: also Wilson’s disease can cause Fanconi syndrome
Nephrogenic strains of Strep Pyogenes cannot cause rheumatic fever because they lack:
M protein Note: RF is type 2 hypersensitivity against M protein (molecular mimicry)
Treatment for Rheumatic Fever
Penicillin, aspirin and corticosteroids (if murmur present)
Non-caseating granulomas in the axillary lymph nodes
Cat Scratch disease (Bartonella hensae)
Splinter hemorrhages & dystrophic calcification in striated muscle
Trichinosis (Trichinella spiralis) Note: from eating undercooked pork
Swollen, painful apocrine glands in axilla and groin infected w/ Staph aureus
Hidradenitis supperativa Note: hallmark is presence of sinus tracts
Pharyngitis w/ erythematous rash the spares circumoral region, sandpaper feeling
Scarlet Fever (Strep pyogenes w/ erythrogenic toxin)
Dermatophytes by location
Tinea Capitis: Blacks-Trichophyton tonsurans,
Tinea Capitis: Whites-Microsporum canis/audouinii
Corporis/pedis/cruris-Trichophyton rubrum
Unguium-Trichophyton rubrum
Organisms at risk in Chronic Granulomatous Disease
Staph aureus, Pseudomonas cepacia, Nocardia, Serratia, Aspergillus Note: Nitroblue tetrazolium test; Nocardia is a branched gram positive
Infection associated w/ non-caseating granulomas
Bartonella henselae–cat scratch disease Note: often in axillary lymph nodes due to scratches on arms
Pts who undergo splenectomy should be vaccinated against
Strep Pneumo (most important) Note: Haemophilus influenza and Neisseria vaccination is also important but Strep pneumo is #1
Most common bacteria in aspiration pneumonia
Oral anaerobes- Bacteroides, Fusobacterium, Peptococcus Note: Right lower lobe abscess; Think Klebsiella if currant jelly sputum
Potential Complication of lymphogranuloma venereum
Rectal stricture Note: Chlamydia trachomatis L1-L3
