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Review #1: General Microbiology 1 Difference between Eukaryote/Prokaryote Eukaryote: sexual reproduction
- example: Algae, fungi Prokaryote: asexual division
- example: Bacteria Eukaryote + Prokaryote: - Are organisms
- They contain all enzymes required for replication/division
- Plus possess the biological equipment necessary for their production of metabolic energy 2 Light Microscope: - Used in bacteriology
- Examination of un/stained smears Electron Microscope: - Detailed structure of pro/eukaryotic observed
- 2 Types: TEM/SEM
- TEM: Good for minute particles/viruses
- SEM: Good for 3-D images of surface of micro.org by
use of shadowing technique or freeze-drying specimens Darkfield Illumination: - Performed on dark microscope
- Creating a darkfield contrasting against the
highlighted edge of specimen
- Used of observing spirochetes
- Ex: Treponnema pallidum
Phase-phase microscope: - Different phases are converted into different intensities so that some structures appear darker than others
- Killed and stained org must be used
Confocal Microscope: - Laser light beams
- Provide 3-D image from thick fluorescent specimen
Auto Radiograph - Radio active atom cells fixed on a slide
- Converts w/photographic emulsion therefore tracks
appear in a developed film
- Useful in following replication of DNA using Tritum
labeled thymidine as tracer
- In Situ hybridization
- Employes labeled nucleic acid probes used to detect presence viral, bacterial + funcgi nucleic acid in cells/tissues 3 Difference between Gram (+)ve and Gram (-)ve cells: Gram (+)ve Gram (-)ve
- Teichoic acid
- Thick
- Peptidoglycan
- Blue Gram stain
- Outer membrane containing LPS
- Thin
- Peptidoglycan
- Red Gram stain
- Endotoxin symptoms (fever, shock) Nature of Gram simple stain bacteria classified on basis of staining reaction stain allows clinician to determine whether org is round or rod-shaped
- Cells stained w/crystal violet
- Treated w/Gram’s iodine
- Decolorization w/acetone or alcohol
- Counter-stain w/safranine or diluted carbolfuchsin
4 Acid Fasting Stains - Aka: Ziell Neelsen Staining
- Used in bacteria that resist decolorization with acid or
alcohol after being stained with strong carbol fuschin
- therefore resulting in their inability to stain
Acid fastness inability to stain due to: High concentration of Lipids called:
- Mycolic acids granules (Lipid-A) (metachromatic granules) 5 What gives bacteria their shape and provides rigid support:
- Peptidoglycan layer in cell wall
- Not in human cells therefore
- Good target for anti-bacterial drugs
- Eg: Penicllin, Cephalosporin inhibiting cell wall synthesis Type of polysaccharide capsule helpful in serological typing of bacteria and determinant to virulence: Polymerized D-glutamic acid Capsule in all gram (-)ve except: - Anthrax Bacillus
Function of a capsule: • Capsule protects organism from environmental
hazards
• Serves as antiphagocytic surface
• Provides specific adherence
Lysosome Enzyme: - Present in human tears, mucus, saliva
- Can cleave peptidoglycan backbone
- Contributes to natural resistance of host to microbial
infection
Lipopolysaccharide (LPS): • Consist of Lipid-A complex lipids
• Endotoxin of gram (-)ve bacteria firmly bound to cell
surface
- Released only when cell lysed
• Target for antibiotics and pyrogenic activity (Fever
induction) Purified form of Endotoxin (^) • Found in outer membrane of gram (-)ve bac
6 Flagella: • Mainly in gram (-)ve
• Organ of locomotion/motility
• Found in UTI
• Major function: mediate adherence of bacteria to to
other bacteria/cells
For serological classification: - Flagellar proteins used are called H-antigen
- Flagellar are organs of motility
- Flagella cell wall = O-antigen
- Capsular called = K-antigen
Pili: - aka: Fimbriae
- found mainly in Gram (-)ve
- 2 Types: Ordinary pili & Sex pili
- Function: Adhesion 7 Spore forming organisms: Clostridium, Bacillus (Both Gram (+)ve )
- Clostridium (anaerobic), Bacilllus (aerobic)
Spores are: - Single internal spore produced under unfavorable
conditions such as nutrition depletion)
11 In Vitro (outside the body) anti-septic/anti- biotic susceptibility testing depends on:
- Type of medium used
- Quantity of organism (inoculum)
- Incubation period
Review #2: Immunology 1 Immunity defn: Resistence by the host towards injury caused by micro.org and/or products Types of immunity: (^) • Acquired – adaptive
- Passive – natural
- Local – destruction at local level
- Herd – control of disease in body Measurement of immunity: - Agglutination, Precipitation, Complement fixation
- Testing level of antibodies Immune Response: (^) Primary, Secondary Humoral (Antibody mediated) response Cellular (Cell mediated) response Immunogenicity deponds on: - foreigness, chemical nature/size Immune reponse altered by: - amount of immunogen, time of exposure, mode of administration and duration of exposure 2 Antigen / Antibody: - response depends on:
- dose, route, timing, administration Antibodies: - Ab are produced in response to Ag
- Abs are immunoglobulins Classes of Immunoglobulins: IgG - Secondary response
- Crosses placenta
- Mainly in internal secretions (blood, CSF) IgM - Primary response
- Presence in fetus intrauterine infection
IgA - Secretory immunoglobulin
- Present in external secretions
- Tears, saliva, sweat, breast milk, GI secretions, Mucous secretion of respiratory tract, Urogenital tract
IgD - Present in traces only
- Found on surface of B lymphocyte
- Marker for B mature cells
IgE - Allergic / antiparasitic responses
Abnormal immunoglobulins - Cryoglubulins, Bence Jones proteins 3 Auto-immune diseases: (^) Chronic thyroiditis + Grave’s Disease
Hemolytic anemia Thrombocytopenia & granulocytopenia Immune deficiencies: (^) Abnormal immune response Could be congenital or acquired
- B-cell (Ab) – recurrent infections
- T-cell – Acquired immuno def syndrome Location of cells:
• B-cells:
• T-cell:
follicles funtn: markers of foreign pathogen paracortex funtn: defense against intracellular patho Cells that attack (protozons): CD4 T-cells 4 Activation cells: o B-cells o T-cells o Macrophages o NK cells o ABO-incompatibility o Rh blood group
IL-
C
gamma-interferon from T-cells Type II hypersensitivity rxns (kill tumor cells) Transplant rejection/Type II hypersensitivity only RBC’s Class I antigen: (HLA-A/B/C) Class II antigen: (HLA-D) CD8 cytotoxic T-cells recognized these antigens CD4 helper T-cells & macrophage recognize these 5 Transplant success requirements: (^) • ABO blood group compatibility
- Absence of anti-HLA cytotoxic Abs in recip.
- Close matches for HLA-A/B/D bet/n donor/recipient Transplant donors Siblings are best donors sources 6 Graft types: o Autograft o Isograft o Allograft o Xenograft Transfer of tissue from self-self, best survival Between identical twins Between unrelated individuals Between one species to another (pig vavles) Corneal transplant: Best overall allograft survival rate 7 Complement fixation rxn: (^) ~Hemolysis test: (-)ve Presence of bacteria (+)ve No presence of bacteria Testing of complement system: C3 is the 1st^ step in complement system ~Classical pathway ~Alternative pathway Low C4 or C2 is activated Low factor B if activated 8 Latex agglutination rxn: Antibody to capsular antigen is attached to beads 9 Examples of hypersensitivit Rxns: Type-I Eczema, hives, asthma, hypersensitivity to bee sting (involves: IgE)(eryth. Lesions w/in 30min) Type-II Goodpasture’s syndrome, Myasthenia gravis
- Cells coated by specific IgG/IgE Abs are destroyed by cells (eg: NK/esoinphils) Type-III Serum sickness, SLE
- Circulating immunocomplexs, IgG/IgM deposit in target tissue activate complement system Type-IV (delayed type) Poison ivy, nickel(metal) contact, soap, tuberculin, dermatitis
- Skin test needs to be performed 10 In acute inflammation: Accumulation of polymorh nuclear cells (PML) Patients deficient in C8 have increased incidence: Meningitis due to Neisseria
- Aka Strep. Pyogenes
- Catalase (-), Beta-hemolytic
- Remain in throat/skin causing sore throat Toxins – produced by group A Streptolysin .O: - Subsurface blood agar
- Hemolysis in anaerobic conditions Strep. S: - Responsible for beta-hemolysis
Streptokinase - Fibrinolysin (plasmaplasminogen)
- Associated with virulence
- IV tx of pulmonary emboli/thromb. Streptodornase - Liquefaction of pus Hyaloronidase - Halornic acid
- Hydrolyses ground substance of connective tissue therefore helps spread infection Strep Exotoxin A-C - Causes fever
- Produce rash of scarlet fever
- Inhibit liver clearance therefore creating shock Sore Throat C/F: - Onset of fever, sore throat, malaise, headache, nasopharyngitis, tonsilar abscess
- All may spread to middle ear, mastoid meninges Dz: Strep. Pyoderma Local infection of superficial layer of skin (IMPEDIGO) Infective Endocarditis Strep may settle on normal or previously deformed heart valves producing endocarditis Sub-acute endocarditis - Involves abnormal vales (congenital deformities, rheumatic fever, artherosclerotic lesions)
- Transient bacteriaemia when Strep accidentally reaches blood (usually seen after dental extractions)
- In these case, prophylactic treatment is used Post Strep. A - Rheumatic fever, Glomerulo-nephritis
- Latent period of 1-4 weeks due to hypersensitivity response Acute Glomerulonephritis - Develops 3 weeks after strep infection
- Nephritogenic stains involves basement membrane
- Blood/protein in urine
- W/edema, hypertension, urea/nitrogen retension Rheumatic fever - Damage to heart muscles/valves
- S/s: fever, malaise, evidence of all parts of heart inflamed (endo/myo/pericardium) leading to thickness of valves (deformities)
- Tx: Prophylactic penicillin prevents pharyngitis
Group B^ – Strep. Agalactie^ -^ Gram (+), Catalase (-), Beta-hemolytic
- Dz: Neonatal meningitis/septicemia
- Pathogenesis: ~(+) cAMP test
~Infection assoc/w/ premature rupture of membrane Group D: Strep. Faecalis (Enterococcous)
- Gram (+), Catalase (-), Enterococcus, variable hemolysis
- Transmission: during medical procedures (GI/Ug) in blood stream onto previous damaged heart valves causing endocarditis
- In colon, urethra, female genitals
- Lab: grows with 6.5 NaCl (& in presence of bile)
- Dz: Urinary/biliary tract infections, endocarditis w/damaged heart
valves
- Tx: problems with drug resistance
Viridans Streptococci
- no group
- S. Sanguis, S. mutans
- Gram (+), Catalase (-), alpha hemolysis
- In oropharynx
- Spread by dental work, poor dental hygiene into blood and
damaged heart valves
- Dz: Sub-acute bacterial endocarditis, dental carries
- Prevention: Prophylactic penicillin **Strep. Pneumoniae
- no group**
- Gram (+), Catalase (-), Lancet-shaped cocci
- Transmission via: resp. droplets
- Pathogenesis: IgA helps in colonization
Teichoic acid present for attachment Polysaccharide cap. virulence factor
- In upper respiratory tract (dz is caused in lower resp)
- Lab: - (+) Quellung Rxn (Swelling of capsule in
presence of antiserum leading to pneumonia)
- Inhibited by optochin
- lysed by bile Toxin of Strep.pneum. Pneumolysin O
- released by capsule
- similar to Strep. O
- when reaches alveoli (lower resp)
- damages cells w/cholesterol
- damages resp. epithelium
- inhibits leukocutes and complement fixation
- outpouring of fluid, RBC, WBC causing CNS inflammation Dz: Bacterial pneumonia, adult meningitis, Otitis media & sinusitis in children Q The principle toxin of Strep. Association with virulence is: Streptokinase Q Acute glomerulonephritis is associated with: Strep. Pyogenes Q Which organism causes subacute bacterial endocarditis: Alpha-hemolytic strep (Strep. Viridans) Q Pneumococci differentiated from Step. Viridans is by: Bile solubility Q Subacute bacterial endocarditis caused by a member of viridian of Strep. Which one is the source of the organism in the this infection: Oropharynx Q A culture of a skin lesion from a patient with pyoderma (impetigo) shows numerous colonies surrounded by zone of beta-hemolysis on blood agar. A gram stain smear shows gram (+)ve cocci. If you catalase test (-)ve, which of the following organism is to be isolated: Step. Pyogenes Q What is the most common infection due to Beta-hemolytic strep.: Strep. Sore throat Q 45-yr-old male w/alcohol abuse, periodontal disease, fever/chills, pneumonia with lung consolidation. CXR shows cavity in right lower lung; what type of bacteria involved: Anaerobic bacteria b/c organism is elsewhere
- causing disease elsewhere (mixed infection) Neisseria - Gram (-)ve cocci occur in pairs
- Capsule prevents phagocytosis
- Endotoxin: produces shock
- Non-motile (kidney shapped)
- 2 types: N. gonorrhea, N. meningitides
- found associated with or inside PMN cells Culture: ~ferment carbohydrates producing acids only ~requires 5-10% CO
2 EPEC (Enteropathogenic) some form of diarrhea
- Watery diarrhea in infants in developing countries ETEC (Enterotoxigenic) - Traveller’s diarrhea
- Heat Labile: Stimulates cAMP
- Heat Stable: stimulates guanylate cyclase, fimbriae EHEC (Enterohemorrhagic) - Severe diarrhea results in acute renal failure EIEC (Enteroinvasive) - Invade human epi cells and cause diarrhea EAEC (Enteroaggressive) - Causes acute/chronic diarrhea in develop.countries 3 SEPSIS - E.coli reaches blood stream and causes sepsis
- Newborns susceptible b/c lack IgM Abs
- May occur secondary to sepsis 4 Meningitis - in infants Q Organism commonly characterized by its O, K, H antigen + ability to ferment lactose: E.Coli Q Organism most likely responsible for UTI: E.Coli Q In the intestinal tract the organism that is lactose fermenting is: E.coli Klebsiella pneumoniae (^) • Gram (-), non-motile
- Lactose-fermenter
• Reservoir: Resp. tract & feces
• Causes: Bacterial pneumonia, UTI, Bacteremia; Hospital
acquired infection
• Dz: Upper lobe cavitation with thick mucous
• Associated with: Alcoholics
• Capsule: impedes phagocytosis
• Endotoxin: Causes fever, shock assoc/w/septicemia
- No exotoxin Tx: (^) • Not susceptible to Penicillin Q Klebsiella p. has the following features except: Susceptible to penicillin Proteus - Gram (-), Motile (flagella)
- Urease (+) / H-antigen (+)
- Produce infection in UTI only when bacteria leaves intestinal tract
- S/s: bacteriaemia, pneumonia, UTI, diarrhea
- Lad: smear not useful but PPA test (+)
Shigella - Gram (-) rod, Non-lactose fermenting, non-motile
- Normal Flora: Intestine (Ileum, Colon)
- Transmission: Fecal/oral spread, person-to-person & Fingers,
food, feces, flies
- Pathogenesis: Infection limited to intestinal tract b/c no blood
stream invasion
- Endotoxin: irritation to bowel wall
- Exotoxin: Type-1: affects gut/CNS; also inhibits sugar and amino
acid absorption in SI
- Enterotoxin: Diarrhea
- Neurotoxin: fatal nature of Sh. Dysenteriae in CNS
C/F: Fever, watery diarrhea, malena, dehydration, acidosis Sh. Dysentriae - Most servere disease Sh. Sonnei - Most common in USA Bacillary dysentery - Infection in intestine
Q Exotoxin that function as a neurotoxin and enterotoxin Shigella dysentriae Q Which species of Shigella is responsbible for basically dysentery in the US: S. Sonnei Salmonella - Gram (-) bacilli, Motile
- Transmission: Oral route, animal/animal products
- Causes: Enteritis, systemic infection, Enteric fever
- Produces: H2S which produces black stool
- Carrier: Gall Bladder, biliary tract
- Antigenic structure includes: Capsular K-antigen but is referred
to as Vi- antigen which may interfere with agglutination
- Lab: Triple Sugar Iron agar, Rapid slide agglutination, Widal test,
Tube agglutination
- Tx: Multiple-drug resistant
- Source of Infection: ~Food/drink (Water/Milk/Cheese)
~Meat/products/eggs Sal. Typhi (D) - Most important classification type Enteric Fever (Typhoid) (^) • reaches SI then lymphatics then blood stream to organs, including intestine then multiply in intestine and finally excreted in stool
- Incubation period: 10-14 days
- Peyer’s patches may be seen due to necrosis Enterocolitis (gastroenteritis) C/F: Nausea/headache, vomiting, perfuse diarrhea S. paratyphi Most common casue of non-typhoid fever and cause of osteomyelitis in pts with sickle cell disease Q Salmonella food poisoning: S. Typhimurium Q Early in course of Typhoid fever, Salmonella typhi is isolated from: Blood Q Which of the following Typhoid antigens is to be most immunogenic:
V 1
Q Outbreak of Typhoid fever occurred in a local high school due to: Cook in school cafeteria Q Which organism produces disease resembling Salmonellosis: Campylobcter jejuni Q Salmonella & Shigella are differentiated in the lab by: Motility Q 6-wk-old infant with 10 days cough/choking; WBC –20% lymphocytes, vomits x2, encapsulated gram (-) ve rods on which media: Triple sugar iron agar or Urease agar Pseudomonas - Gram (-) rods, aerobic, Motile
- Oxidase (+) / H-antigen (+)
- Produce pigment
- Tx: Multi-drug resistant
Helicobacter - Gram (-) spiral shaped
- Multiple flagella H-antigen (+)
- Oxidase (+), Catalase (+), Urease (+)
- Culture: Grows at neutral pH
- Associated with gastritis, duodenal (peptic) ulcers/carcinoma,
gastrointestinal lymphomas arising from MALT in stomach
- Found deep in mucus layer near epithelial surface
- Pathogenesis: Produces protease modifying gastric mucosa
(causing ulcer) which requires biopsy for diagnosis
- Lab: Detect urease activity
- Tx; Triple Therapy for 14 days
Yersenia - Gram (-), short, safety-pin appearance
- Catalase (+), Oxidase (+)
- Endotoxin: ~Bubonic plague by bite
~ Lymph node enlargement ~ Primary pneumonic plague
- Transmission: Inhalation of droplets causing sepsis/death
- S/S: Lymphadenopathy, high fever, hypotension, renal failure
Y.Peptis - Produces plague (black death) Y.Pseudotuberculosis - Respiratory pneumonia Y.enterocolitis - Contaminates blood during transfusion
- Triggers ankylosing spondylitis
- Diarrheal disease Pasturella - Gram (-), small rods
- Reservoir: Mouths of animals (cats/dogs)
- Transmission: By bites
- Diagnosis: Wound infection – Cellulitis w/lymphadenitis
- Exotoxin: Capsule spreading within skin rapidly
- Tx: Amoxicillin
Haemophilus (“blood loving”)
- Capsule: Virulent factor
- Exotoxin: none
- Normal Flora: Upper respiratory tract w/possible extension into
middle ear and sinuses
- Transmission: Respiratory tract (person-to-person) especially in
children (5mo –5 yr)
- Lab: Isolated by blood
- S/s: Inspiratory stridor, lateral neck x-ray revelas thumbprint
- Culture: ~Brain heart infusion agar w/blood
~Growth requires X(blood)+V(NAD) factor
- Immunization Capsular vaccine
H. Influenzae B Common cold (most virulent of all) H. ducreyi -STD (Chancroid) w/ Ulcers on genitalia, inflame/tenderness -Diff/Diag: Syphilus, Herpes Simplex H. Influenzae A-F Flu Dz: Meningitis (very common among children and if left untx may be fatal), Pneumonia, Empyema, Epiglottitis, Cellulitis Secondary Dz: Chronic bronchitis, otitis media, sinusitis Q 4-yr-old with respiratory distress with 103.8oF fever; drools, difficulty swallowing, stridor. CXR shows epiglottis swelling. Infant has never had a vaccine: H. Influenzae
Bodetella B. Pertusis Whooping cough disease
- Morphology: Resembles H. Influenzae
- Capsule: present
- Lab: Blood isolation
- Exotoxin: Irritate surface cells producing cough/ lymphocytosis
- Transmission: Respiratory route (person-to-person)
- Pathogenesis: Adhere/multiply on epi-surface of trachea, bronchi
and interfere with ciliary axn
- Dz: Untx leads to necrosis of epithelium with PMN infiltration and
peribronchial inflammation therefore resulting in interstitial pneumonia
- Secondary Dz: Bact. Pneumonia with atelectasis and decreased
O2 in blood leading to tertiary dz of convulsions in infants
- Immunization: DPT containing killed bordetella bact.
Different Stages Catarrhal: Paroxsymal
- Mild coughing/sneezing
- Shed large # of org
- Not very ill
- Incubation: 1-2 weeks
- Exploxive coughing w/ “Whoop” upon inhalation
- Rapid exhaustion w/vomiting, cyanosis, convulsions
- Incubation: 2-4 weeks Q ADP-ribosyl transferase which effects G-regulatory protein causes increase cAMP levels: Pertussis toxin Q Paroxysms of cough known as Whooping cough which organism involved: Bordatella pertussis Brucella (^) • Gram (-), Oxidase (+), Urease (+)
- Typically infest animals
• S/S: Malaise, fever, weakness, aches, sweats, GI &
Nervous symptoms, lymphadenopathy
- Acute infection leading to chronic
- Serology: 1st^ week increased IgM
4 th^ week increased IgG B. melintensis Brucellosis Infects goat
- Fever, acute bacteriaemia, non-motile, gram (-)
- Isolation in blood
- Transmission: ~Intestinal tract (infected milk/products)
~Mucous membrane ~Skin (contact w/inf animals
- Spreads via lymphatic channel, thoracic duct, blood stream
- Dz: affects paraenchymal organs leading to abscess in
liver/spleen/bone marrow
- Secondary: Osteomyelitis, meningitis, cholecystitis
B. arbortus - Increased Co2 for growth
- Mild dz
- Non caseating granuloma
- In pregnant animals, infection reaches placenta causing: Placentitis & Abortion
- However not in humans Q 16-yr-old girl with enlarged lymph node (Right axilla). Blood count – normal; Granulomas w/neutrophils + necrotic debris. Which org: Brucella Henselae (also responsible for cat scratch disease) (??bartonella)
- Inhibits protein synthesis by ADP-ribosylation of EF
- Stain: blood samples will not be helpful b/c it does not enter bloodstream
- Virulence test: Eleks test
- Prevention: w/toxoid (active) immunization DPT
- Tx: Pencillin, Erythromycin (inhibits growth of bacteria)
Q Corynebacterium diphtheria: Child should be given toxoid Q All are correct about corneybacteria except: C. Diptheria toxoid shouldn’t be given to kids under 3 years b/c incidence of complication is too high Clostridium - Gram (+) bacilli, Motile
- H-antigen (+) with flagella
- Culture: Grows under anaerobic conditions
- Reservoir: Found in intestinal tract
C. Tetani - Transmission: Puncture wounds/trauma (produces tetanus)
- Extreme muscle spasm
- Blocks release of inhibitory mediators at spinal synapses C.Botulinum - Produced in poorly preserved food (canned beans)
- Symptoms: Weakness, dizziness, blurred vision
- Muscle paralysis Infant botulism - Household dust ingested
- Causing constipation, limpness diplopia/dysphagia (floppy baby)
- Toxin produced in gut Wound botulism - Traumatic implantation of spores
- In Vivo production of toxin
- Tx: Penicillin
- Blocks release of Ach at myoneural junction in flaccid paralysis
- Heat labile C.Perfringenes - Non-motile
- Found in soil, human colon
- Dz: Gas gangrene (myonecrosis) Alpha-toxin of C.p - Disrupts membranes hemolyzing RBC, damaging platelets Entertotoxin - Causes food poisoning
- Disruption of ion-transport watery diarrhea and cramps
Cl. difficile - Pseudomembranous colitis
- Yellow plaques on colon
- Production of lecthinase Q Causes muscle paralysis: Botulinum toxin Q The most important for preventive function of the antibody stimulated by Tetanus: To neutralize the toxin of the pathogen Q All correct about Clostridium Perferinges except: Gram (-)ve rod that does not ferment lactose Q Which concerning immunization against disease caused by clostridrium is correct: Immunization with tetnus toxoid induces effective protection against tetnus Q What organism causes gas gangrene: C. Perfringes Q Each is true concerning wound infection caused by perfringens except: Organism grows only in human cell culture Q Causes muscle spasms: Tetanus toxin Q Causes nyonecrosis: Clostridium alpha-toxin
Virulence tests - In Vitro Elk’s test (neutralization test / horse serum)
- In Vivo inoculation and observation
Listeria Monocytogenes Perinatal human listeriosis Listeria meningitis
- T: Oral – GI tract
- Eating unpasteruzied cheese (Goat milk’s cheese)
- Motility: 22 o^ – yes 37 o^ no
- Manifestation early intrauterine sepsis/death/meningitis in
neonates/adult transplant patients
- Path: Invades mononuclear cells
- Stain: Beta-hemolysis in blood agar and CSF culture
- Tx: Ampicillin
Q 28 yr-old preg. Women with fever, headache, myalgia, pain and spontaneous abortion: Listeria monocystogenes Q Neonate with widespread granulomas in uterus: Listeria monocystogenes commonly acquired from uterus Bacillus Anthrax Woolsorter’s disease
- Gram (+)ve rod, spore-forming, aerobic
- Polypeptide capsule of D-glutamic acid
- Resistant to heat
- T: Skin/mouth/inhalation
- Manifestations: Skin ulcers/malignant pus, pneumonia in people
working with animal (hides), soil,
- Tx: Pencillin
- Prevention: Immunization with live vaccine
Q Bacillus Anthrax: Causes Woolsorters disease Mycobacteria - No gram stain, Rod shaped, aerobic, non-spore
- Not easily stained and if stained- resist decolorization
- Therefore: Acid fast bacilli Many Types - M. Tuberculosis, M. Avium, M. Bovis, M. Leprae, M. Ulcerans, M. Balnei, M. Butyricum, M. Phelei, M. Sterocori and atypical mycobacteria
M. Tuberculosis - Catalase (-), Aerobic, Acid Fast bacilli
- Cell wall with mycolic acids (increased lipid content) induces
delayed hypersensitivity (resistance to inf)
- Culture: ~Slow growth (3-6 wks),
~Produces Niacin ~Salt solution required M.tub.Hominis Respiratory Tuberculosis (most common) M.tub.Bovis Intestinal
- Transmission: Inhalation – reaching alveoli where it fully
establishes and proliferates
- Lesions: Exudative type
• Ac. Inflame.rxn, edema w/fluid, PMN, Peyer’s Patches
with obstruction in terminal ileum
- (+) Tuberculin test (leads to hypersensitivity and resistence to recurrent episodes) Productive type
- Chronic granuloma in Central (multinuc.giant cells), Midzone (Pale epi-cells), Peripheral (Fibroblasts)
- Tx: drug resistance common especially in immune.supp pt. Tuberculin test - (+)ve test does not prove presence of active dz therefore isolation of organism needed for diagnosis Atypical Mycobacteria - Non-tuberculosis mycobacteria
Q Maculopapular rash, shock + renal failure 3 days after returning from camping trip in east USA. Which org responsible for symptoms: Rickettsia ricketsii (aka: Rocky mountain spotted fever) due to ticks Nocardia - Gram (-), aerobic
- Predominantly respiratory pathogen
- Seen in patients with defects in cellular immunity
- Ex: Heart transplantation
- Produces micro abscesses in lung with granulomas N.asteroids - Partially acid fast Review #5: Virology Measles Virus aka Rubeola
- S/s: Child with fever, sore throat & ulcerative lesion on soft
palate (Kopliks spots).
- From Paramyxovirus family,
- Transmission: inhalation
- Vaccine preventable 4-yr-old male with fever, sore throat, unusal irritability. P/E shows 10-15 small, gray which shallow ulcerative lesions along posterior margin of soft palate. Pharyngeal walls-red. No lesions on gums. Child is of dark complexion with no obvious rashes. Q Disease: Measles Q Lesions found on mouth known as: Koplik’s spots Q Causative agent: Paramyxovirus Q Transmission of disease by: Inhalation of droplets Q Another name for disease: Rubeloa Q Example of arthropod-bone viruses causing encephalitis in humans including all except: Measles virus Mumps - Involves Salivary glands(Parotids)
- Vaccine preventable Rabies Virus Rabdovirus
- Rod or Bullet shaped
- Negri bodies diagnostic
- Virus destroyed by UV radiation
- Culture: Multiplies in muscle & conn. Tissue
- Infection of the CNS
- Incubation 21-60 days. Isolation by Saliva for rabies virus. Q Which virus belongs to rhabdovirus group that resembles a bullet, flat at one end? Rabies Infection spread by vector Rabies Inf.prod vesicular lesions Aseptic meningitis Resp. infection Infe in throat or intestine Blood Saliva Vessicle fluid CSF Throat swab Throat swab + feces Q Rabies source of specimen for virus isolation: Saliva Q Colorado tick fever cultured on: Blood Q Coxsackie specimen isolated on: Throat swab + feces
Q Influenzae specimen isolated on: Throat swab Q HSV specimen isolvated on: Vessicle fluid EBV - Nasopharngeal carcinoma
- Burkitt’s lymphoma. Q Burkitts + Nasopharyngeal carcinoma: EBV HPV (Papilloma virus) Cervical carcinoma Q Cervical carcinoma: HPV Herpes Simplex (^) I oral lesions (painful) II genital lesions (painful) Herpes zoster aka Shingles
- affects nervous system
- dorsal nerve root of trunk involved Q A viral org. was isolated from a painful blister on the lip of a teenager girl. Agent was found to be double-stranded, linear DNA and was enveloped. The patient had similar sore 2 months ago: Herpes Simples I (HSV) RSV - Cause of pneumonia & bronchiolitis in infants.
- Only respiratory viruses
- ****Rota viruses do not cause respiratory viruses Coxsackie Group B, type 1-6: aseptic meningitis Coxsackie Comm... cause of myocarditis and pericarditis Q The illness which often results infection w/Poliovirus, Coxsackievirus and Echovirus is: Aseptic meningitis Rhinovirus Do not cause gastroenteritis Rhinovirus - Common cold in fall and winter - Winters disease
- Reservoir is school children.
- Transmission: Inhalation droplets Adenovirus Virus responsible for cold in spring and summer. Live vaccine -Oral Polio Vaccine (OPV) -Produces lasting intestinal immunity Live vaccine in AIDS MMR Q Which strategy like to induce lasting intestinal mucosal immunity to poliovirus: Oral vaccination w/live vaccine Q 9-mo-old infant is brought to health dept. for second dose of OPV (oral polio virus) 2 weeks after 1st^ vaccine. Child has mild diarrhea and decision is made to defer 2nd^ dose. Bacterial exam of stool is unremarkable but a small, single strand positive RNA virus is isolated. Same agent in sewage effluent previous week. Viral isolated not affected by either: Poliovirus Varicella Primary disease of children Q Varicella is: Primary disease of children Rotavirus Common cause of diarrhea in children / ELISA for diagnosis Q 6-months child with persistent cough + fever, physical exam and CXR suggests pneumonia. Which org is lease likely to cause infection: Rotavirus Cytomegalovirus (CMV) - Comm. Cause of diarrhea
- Biliary tract disease & pancereatitis in AIDS
