Microbiology - Final - Part 3

davidwurbel7's version from 2015-08-14 03:59


Question Answer
White colonies. Non-hemolytic BA. MSA - does not ferment mannitol. Novobiocin sensitiveStaphylococcus epidermidis
Biofilm production. Subacute endocarditis. Prosthetic joint infections. Infections of IV lines, shuntsStaphylococcus epidermidis
GPC clusters. Catalase +. Coagulase –. Non-H on BA, white colonies. Resistant to novobiocinStaphylococcus saprophyticus
S.pyogenes and S. agalactiae hemolysis on blood agarBeta-hemolytic
S.pneumoniae and Viridans strep hemolysis on blood agarAlpha-hemolytic
Viridans strep and Group D strep hemolysis on blood agarGamma-hemolytic
Group A Strept (GAS). GPC chains. Catalase negative. Beta-hemolytic on Blood agar. Bacitracin sensitiveStreptococcus pyogenes
Antiphagocytic. Repeated Strep throat infections due to different strainsM Protein
Antibodies. Produced only in pharyngitis. Not produced in skin infections. High titers in Acute rheumatic feverStreptolysin O (ASO)
Marker for recent Strep A infection. Both skin & throat infections. Helps in diagnosis Streptococcal glomerulonephritisAnti-Dnase B antibodies
Superantigen. rash of scarlet fever. Toxic Shock Syndrome (TSS). Positive blood culturesStreptococcal Pyrogenic Exotoxins (SPEs)
Toxic Shock Syndrome with negative blood culturesStaph aureus
Toxic Shock Syndrome with positive blood culturesStrep pyogenes
Complication of strep throat. Strain producing a SPE. Red rash followed by desquamation. Strawberry tongue Scarlet fever
Pharygitis, pharyngotonsilitis. Exudative, red. High feverStrep Throat
Honey-crusted lesion with or without Staph aureusImpetigo
Spreading inflammtion – red, raised, painful. Face, legsErysipelas
Strep gangrene. Very painful,rapidly spreading, fatalNecrotizing fasciitis
Develops after untreated/inadequately treated Strept throat infection. 2-4 weeks after. Children 5-15 yrs. History of GAS pharyngitis positive serologic tests (ASO)Acute Rheumatic fever
Occurs after a severe episode of ARF or many attacks of ARF. 10-20 years after these ARF episodes. Due to damage to the mitral and aortic valvesChronic Rheumatic Fever
Acute inflammation of renal glomeruli. Immune-complex disease. Edema, hypertension, hematuria, proteinuria. Follows skin / throat infection 1-2 weeks after. Smoky/coal-coloured urine. Generalized edema. Moderate proteinuriaAcute glomerulonephritis
Streptococcus pyogenes treated withPencillins
GPC chain. Catalase – . Weak beta-hemolysis on BA. Bacitracin resistant. CAMP test positive. Hydrolyze hippurateStreptococcus agalactiae
Immediately after birth (early onset). After 2-3 weeks (late onset). Bulging fontanelle, high fever, irritability. CSF=turbid, GPC chains + neutrophilsNeonatal meningitis
GPC pairs (lanceolate/flame-shaped). Polysaccharide capsule. Alpha-hemolytic on BA. Biochemical tests - Bile soluble, Optochin sensitive, Positive quellung reactionStreptococcus pneumoniae
MCC community-acquired lobar pneumoniaStrep pneumoniae
High fever, nuchal rigidity, photophobia, headache, altered mental status, vomiting. CSF = turbid, Neutrophils + GPC pairsBacterial meningitis
(Insert GPB.42 - 46)
Question Answer
GPC (pairs and short chains). Catalase negative. Growth in 6.5%NaCl. Hydrolyze esculin in 40% bileEnterococcus
GPR. Cuneiform “chinese letter” . Tellurite /Tinsdale medium. Eleks test – toxin detectionCorynebacterium diphtheria
Inhibits protein synthesis - ribosylation of EF-2. Also binds to heart and nerve tissuesDiphtheria toxin
Untreated Diphtheria can lead to thisAcute Myocarditis
Large GPR (long chains). Endospores. Emetic form - Contaminated rice. Diarrheal form - meat, fish, vegetables, or saucesBacillus cereus
Also potato, pasta and cheese dishes. Vomiting, nausea, cramps. Within 1 – 6 hoursBacillus cereus Emetic form
Diarrhea, abdominal cramps, nausea. 6-14 hoursBacillus cereus Diarrheal form
GPR (Large, box-car like bacilli in chains). Endospores. Capsule – poly-D-glutamate. Edema toxin. Lethal toxin. Types - Cutaneous; InhalationalBacillus anthracis
Spores inoculate skin abrasion. Central black eschar with surrounding pustules “malignant pustule”. Surrounding redness + extensive edemaCutaneous anthrax ( hide-porters disease)
Inhalation of spores. Biphasic illness. Phase 1 – mild upper respr tract sypmtoms. Phase 2 – fever, tachycardia, chest pain. Widened mediastinum. Enlarged hilar lymph nodes. Meningitis, rapid deathPulmonary anthrax (Woolsorters disease)
Small GPR. Facultative Intracellular bacterium. Tumbling motility. Cold growth - Grows at refrigeration tempsListeria monocytogenes
GPR with bulging spores. anaerobe. Spores found in - Soil, splinters, rusty nails. Produces tetenospasinClostridium tetani
Blocks release of inhibitory neurotransmitters glycine and GABA (gamma-aminobutyric acid). Causes spastic paralysisTetanospasmin
Lock jaw (masseter). Risus sardonicus (facial muscles). Opisthotonus (arching back, spasms in back mucles). Difficulty swallowing, sweatingTetanus
Anaerobic GPR, endospores. Spores in hospital (bathrooms, bedpans). Ingestion of spores – colonization of GI tract. Hospitalized pts on antibiotics. Antibiotic-assoiciated diarrhea. Pseudomembranous colitisClostridium difficile
Anaerobic GPR, endospores. Spores contaminate foods, wounds – toxinClostridium botulinum
Block release acetylcholine at the neuromuscular junction resulting in flaccid paralysisBotulinum toxin
Blurred vision, dry mouth, descending paralysisFoodborne botulism
Floppy baby. Usually from eating honeyInfant botulism
Anareobic GPR, endospores. Alpha toxin. Lecithinase / phospholipase C. Breaks down lecithin in cell membranes. Damages RBCs, WBCs, platelets, endothelial cellsClostridium perfringens
Pre-cooked foods – beef, gravies, poultry contamined by endospores. Enterotoxin produced. Watery diarrhea, 8-18 hours laterClostridium perfringens food poisoning
Endospores introduced into tissues – surgery/trauma. Discolored skin, hemorrhagic bullae, gas in tissues – crepitus. Rapidly progressing – fatalClostridium perfringens gas gangrene
GNC pairs Oxidase + Catalase +. Breaks down only glucose. Pili Antigenic & phase variation. Lipid Oligosaccharide (LOS). Thayer Martin medium = Chocolate agar + AntibioticsNeisseria gonorrhoeae
Urethritis, prostatitis, epididymitis. Purulent exudate. GS = neutrophils + GNC pairsGonorrhea Male
Urethritis, endocervicitis, PIDGonorrhea Female
MCC of septic arthritis in sexually active (teens – 50 yrs)Neisseria gonorrhoeae
GNC pairs encapsulated. Oxidase + Catalase +. Breaks down Maltose and Glucose. Polysaccahride capsule. IgA protease. Endotoxin – Lipooligosaccharide (LOS)Neisseria meningitidis
Common cause of meningitis (2-18yrs) College dorms, military barracks, schools. Fever, headache, neck stiffness, photophobia, vomiting, Petechial rash, turbid CSF, neutrophils + GNC pairs. Low glucose, high proteinNeisseria meningitidis Meningitis
Bilateral damage to adrenal glands due to meningococcemiaWaterhouse-Friderichsen syndrome
GNC pairs/coccobacilli. Otitis media + sinusitis. Bronchitis + pneumonia – elderly pts with underlying pulmonary problems (COPD)Moraxella catarrhalis
GNB. Oxidase – . Ferment glucose. Nitrates → nitrites. Differentiate on MacConkey agarEnterobacteriaceae
GNB. Oxidase – . Reduce nitrates to nitrites. Lactose fermenting – pinkE. coli
Watery diarrhea. Travelers diarrhea. LT – similar to cholera toxin. ↑cAMPETEC
Watery diarrhea. Infantile diarrhea. A/E lesions (attaching , effacing) – malabsorptionEPEC
Bloody diarrhea. Shiga-like toxin. Bovine feces. Undercooked hamburgers. Unpasteurized juices, cider, milkEHEC O157H7
Invasive diarrhea, found in developing countries. Low-volume bloody stools, WBC present with high fever (Dysentery)EIEC
MCC of urinary tract infection (community-acquired)E. coli
Neonatal meningitis. Bulging fontanel, high fever, irritability, poor feeding. CSF turbid, GS = neutrophils + GNB. Low glucose, high protein, neutrophilsE coli K1
GNB. Oxidase –. Lactose-fermenting (pink). Mucoid (encapsulated). Community-acquired pneumonia (alcoholics/elderly). Currant-jelly sputum. In hospitals - Ventilator-associated pneumonia (VAP). Catheter-related UTIKlebsiella pneumonia
GNB. NLF (colorless on MA). oxidase – . Swarming growth on media. Urease +. Kidney stones – staghorn renal calculiProteus
GNB. Oxidase – . NLF. Non-motile. Bloody diarrhea. Invades mucosal cellsShigella
GNB, oxidase negative, NLF, motile, H2S, Vi antigenSalmonella
MCC osteomyelitis in Sickle cell disease ptsSalmonella paratyphi
GNB - bipolar staining. Oxidase – . NLF. Survives in cold environments. Unpasteurized milk, pork. Bloody diarrhea. Sometimes appendicitis-like symptomsYersinia enterocolitica
Curved GNB, Oxidase + . Shooting star (darting) motility. Source – Water. TCBS medium - Thiosulphate citrate bile salts sucroseVibrio cholera
Activates adenylate cyclase, increases cAMP resulting in hypersecretion of water + electrolytesCholera toxin
Vibrio cholera treated withRehydration + Doxycycline
Curved GNB, Oxidase + . Shooting star (darting) motility. Warm marine coastal waters. Exposing cuts/abrasions to contaminated seawater. Eating Raw shellfish, oystersVibrio parahemolyticus or Vibrio vulnificus
Vibrio parahemolyticus and Vibrio vulnificus treatmentDoxycycline or Cephalosporin
GNB, curved, spiral, gull-wing. Oxidase + . Microaerophilic, grows at 42oC. Found in Poultry, Dogs, other animals. Causes bloody diarrheaCampylobacter jejuni
MCC of bacterial gastroenteritis in USCampylobacter jejuni
Campylobacter jejuni treated byFluoroquinolones
Curved GNB. Oxidase + . Microaerophilic. Stomach. Urease positive. Gastritis. Peptic ulcers. Urea breath test. Chronic infection associated with gastric adenocarcinoma and gastric B cell lymphomaHelicobacter pylori
Helicobacter pylori treated withProton-pump inhibitor + Ampicillin + Clarithromycin