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Final Exam
Medical Microbiology
142
Microbiology
Undergraduate 4
12/11/2012

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Term
Rhinitis
Definition
URT
-Cold.
-Viral: Rhinovirus & coronavirus
-cilliated epithelial cells of nose
Term
Pharyngitis & Tonsilitis
Definition
URT
-Sore throat and tonsilitis
-Infected mucosa and lymphoid tissue
-Cytomegalovirus(CMV) blood to placenta
-EBV.
-S. pyogenes/N. gonorrhoeae/C. diptheria
Term
Otitis media and sinusitis
Definition
URT
-Ear & sinus
-50% viral & 50% bacteria
-Respiratory syncytial virus (RSV)/Influenza/parainfluenza/rhinovirus/adenovirus
-S. pneumoniae/Haemophilus influenzae/Moraxella
Term
Epiglottitis
Definition
URT
-H. influenzae type B(vaccine Hib)
-Ages 2-7
-Symptoms: Drooling/dysphagia/respiratory distress
-Life threatening if severe inflammation
Term
Laryngitis & tracheitis
Definition
LRT
-Virus:Parainfluenza(croup=barking seal)
RSV, Influenza, Adenovirus
-Bacteria: GAS, H. influenzae, S. Aureus
-C. diptheria(life threatening but vaccine-DaPT)
Term
Whooping Cough/Pertussis
Definition
LRT
-Bordetella pertusis
-Attach to ciliated mucosa in trachea (fimbriae & hemagglutinin-prevents cilliary movement)
-Toxic factors:
1.Pertussis toxin-Prod mucoid secretions
2.Adenylate cyclase toxin-Inhibits chemotaxis,phagocytosis, & killing
3.Tracheal Cytotoxin-Kills tracheal epitherlia cells
4.Endotoxin
90-95% rate of infection if exposed to unvaccinated
Term
Acute Bronchitis
Definition
LRT
-Inflammation of the tracheal/bronchial tree
-P. pathogens: Rhino corona, adeno, influenze viruses & Mycoplasma pneumoniae
-Secondary invaders-S. pneumoniae, H. influenzae
Term
Influenza
Definition
LRT-The flu
-Influenza virus types A, B, C,; A segmented RNA, 3 HA types, 2NA types
-Antigenic epitopes change from yr-yr(drift and shift)
-Airborne droplets
Term
Influenza Colonization
Definition
-Attaches via HA to sialic acid receptors on ciliated epithelium of trachea/bronchi
-RME
Term
Pathology of Influenza
Definition
-Incubation 1-3 days
-Impair mucociliary clearance, tacheobronchitis, bronchospasms;cytokines released from damaged cells & WBC
Term
Presentation of Influenza
Definition
-Fever of 102-104
-Chills
-Severe headache w/retro-orbital pain
-Muscular aches
-Dry cough
-Weakness

Resolves in 1-2 weeks
Term
Complications of Influenza
Definition
Primary influenza-1% of cases but 30% fatal. Pregnant women at increased risk

Secondary Bacterial pneumonia-H. influenzae, S. pneumonia, S. aureus, S. pyogenes
Term
How many cases are required for influenza to be considered epidemic?
Definition
10,000-50,000 DEATHS
Term
Bronchiolitis
Definition
LRT
-Children <2
-Necrosis of epithelial cells lining bronchioles

-75% RSV (Respiratory Syncytial Virus)
Colonization:Nasopharynx-surface spikes are fusion proteins that fuse host cells to cause syncytia. Virus invades LRT by surface spread in secretions.
-Maternal Ab in infants react w/virus
-Presentaion:bluish ashy lips/cough/rapid respiration

-25% Other viruses
Term
RSV
Definition
Respiratory Syncytial Virus
Paramyxovirus(RNA), enveloped
Humans only reservoir
Transmission:Resp. droplets to hands
Term
Pneumonia
Definition
LRT
-Pathogen clinically indistinguishable
Transmission: Inhalation of rep. droplets or aspration from UR
Colonization: Attach to rep. epithelium
Pathology: Respdistress from the interference of gas exchange in lungs,
Children: Viral maybe bacterial
Adults: Bacterial
Term
Bacterial Pneumonia
Definition
Acute onset, high fever
Typicals: S. pneumoniae, H. influenzae, S. aureus, Klebsiella, E. coli, Pseudomonas
Atypical: M. pneumoniae, Chlamydia pneumoniae, Legionella pneumophila, Coxiella burnetii
-Chest Exam for: Rales(abnormal crackles)/Evidence of consolidation/Chest X-ray
Term
Viral Pneumonia
Definition
Transmission: Inhaled or from blood
Colonization: Attach specifically
Orgs: RSV-Chlidren
Parainfluenza virus-Children; hemagglutinin & neuraminidase & fusion proteins
Adenovirus
Influenzavirus
Term
Fungal Infections of LRT
Definition
Chronic
-Aspergaillus fumigatus: predisposing condition or immunosuppressed individuals. 45 degree branching septate hyphae present

-Histoplasma Capsulatum-Histoplasmosis

-Coccidiodes immitis-San Joaquin Valley Fever

-Blastomyces dermititidis-blastomycosis

-Pneumocystis jiroveci-pneumocystis pneumonia
Term
Cystic Fibrosis
Definition
Very Viscous bronchiol secretions leads to fluid stasis in the lungs & infections w/P. aeruginosa (S. auresus, H influenzae, B. cepacia

CF patients over reactive inflammatory response= too many PMNs, too much secretion=damage to mucosal epithelium, fluid stasis=bacteria are not removed
Term
NK cells
Definition
viruses & I.C. bacteria
Term
Interferon
Definition
Viruses
Term
Phagocytosis
Definition
PMN, E.C. bacteria
Term
Complement Activation
Definition
E.C. bacteria
Term
Steps for Infectous Microbes
Definition
1. Entry
2. Spread
3. Multiplication
4. Evasion
5. Transmission
6. Pathology
Term
Gram Positive vs. Gram Negative Cell Wall
Definition
GP: LTA
Thick peptidoglycan
resists activity of bile
Digested by lysozyme which targets beta 1-4 glycosidic linkages

GN: Thin peptidoglycan
LPS-Carbs: Stimulates immune response
Lipid A: Endotoxin that induces fever, ^vascular permeability
Term
Importance of Capsule
Definition
-Attach to a wide variety of surfaces
-More resistant to engulfment by host defense cells
Term
Importance of Flagella
Definition
-Movement
-Proteins are stongly antigenic/immune simulating
Term
Importance of Fimbriae
Definition
-aka common pili
-Attachment(adhesins target cell membranes)
Term
Importance of Pili
Definition
-Exchange genetic info, including antibiotic resistance
Term
Entry of bacteria into host
Definition
-Direct contact
-Ingestion
-Fomites(inanimate objects)
Term
Clinical significance of normal microbiota
Definition
-Common contaminants of clinical specimens
-Opportunistic pathogens
Term
Opsonin
Definition
Molecule that attaches to cells; providing a bridge to receptors on phagocytic cells and enhances the rate of phagocytosis
Term
Edema
Definition
Excess accumulation of serous fluid in connective tissue or in a serous cavity
Term
Erythema
Definition
Abnormal redness of the skin due to capillary congestion (as in inflammation)
Term
Inflammation
Definition
locall response to cellular injury
Marked by: Capillary dilation, leukocytic infiltration, redness, heat, pain, swelling, & often loss of function
-Serves as a mechanism initiating the elimination of noxious agents and damaged tissue
Term
Non-specific Physical Defenses
Definition
-Overlapping epithelial cells
-Turbulence in nose that makes it hard for MOs to attach
-Shedding, scrapping, flushin(saliva, urine, tears)-Shear force
-Muco-ciliary clearance-goblet & ciliary cells
Term
Non-Specific Chemical Defenses
Definition
1. Acids
2. Enzymes(lysozymes)
3.Microbiciidal chemicals (zinc & dermicidin)
Term
Non-Specific Biological Defenses
Definition
1. Normal microbiota-Physical, competition, inhibitory substances
2. Immune defense cells and molecules
Term
2nd line NS Defense
Definition
Inflammation
-phagocytic cells
-cytolytic cells
-acute phase proteins: CRP, interferon, and complement
Term
Signs of acute inflammation
Definition
1. Erythema-redness
2. Edema-swelling
3. Heat
4. Pain (sensitivity to area)
Term
Triggers of accute inflammation
Definition
1. IM
2. Peptidoglycan, LTA, LPS
Term
Roles of phagocytes
Definition
-Engulf & destroy foreign matter
-Secrete chemicals (cytokines)
Term
Types of phagocytic cells
Definition
-PMN=neutrophils
-mononuclear leukocytes
Term
PMN
Definition
-Dominant in beginning of inflammatory response
-Contains cytoplasmic granules loaded with antimicrobial chemicals
-Best with extracellular pathogens
Term
Mononuclear Leukocyte
Definition
-Later in inflammatory response
-Concentrated in lung, liver, lymph nodes and spleen
-live longer than PMNs
-APC
-Best with intracelular pathogens
Term
Which type of phagocyte is best against extracellular pathogens?
Definition
PMNs
Term
Microbe-PAMP to PRR-Phagocyte
Definition
Allows microbe and phagocyte to overcome negative-negative charge repulsion since both have exterior negative charges.
Term
NK cells
Definition
-Target viruses
-attach to infected to cells via glycoproteins
-release perforins & granzyme to kill cell
Term
Th1, Th2, Tregs
Definition
CD4
Term
Tc
Definition
Cytotoxic T cells
CD8
Kills cells infected w/intracellular pathogens
Term
Which MHC class do Th cells recognize?
Definition
MHC class 2
Term
What MHC do Tc recognize?
Definition
MHC class 1
Term
Activation of T lymphocytes
Definition
1. Receive cytokines from APC(IL-1)
2. ^ of IL-2 Received adn secrete/receive Il-2=proliferation
3. Differentiation into: effector Th1 cells(activate macrophages=NK & Tc) & Th2 (activates B cells to make antibodies)
Memor Tcells
Term
IL-2
Definition
-Secreted by Th1
-Stimulates Tc proliferation & maturation
Term
IL-4
Definition
-Secreted by Th2
-Stimulates B cell proliferation & differentiation into plasma cells
Term
gamma-interferon
Definition
-Secreted by Th1 cells
-Activates effector Tc, macrophages and NK to kill intracellular pathogens
Term
Opsonizing agents
Definition
C3b
CRP
IgG
Term
What is a neutralizing antibody?
Definition
IgA
Term
Rheumatic Heart Disease
Definition
Delayed sequela of URT infection with group A beta-hemolytic strep
Abs that target strep bind to heart tissue due to similarity in receptors. IS cross reacts w/heart and kidneys
Term
Antigenic Drift
Definition
Caused by single base mutations in RNA. Slight changes in hemagglutinin (H) of influenza virus
Seasonal Epidemics
Term
Antigenic Shift
Definition
Major changes in surface proteins caused by recomvinationg of genes b/w 2 different strains of virus.
Pandemic
Term
What MO produce IgA protease?
Definition
Nice STriP of Ham
Neisseria
Streptococcus pneumoniae
Haemophilus influenzae
Term
Which cytokines are responsible for fever?
Definition
IL-1 & TNF
Term
Physiological cause of fever
Definition
Hypothalamus secretes PG upon binding of IL-1 or TNF. PG then self activates the hypothalamus
Term
Type 1 Hypersensitivity
Definition
IgE
rapid onset
Term
Type 2 Hypersensitivity
Definition
IgG
activated mins to hrs
Term
Type 3 Hypersensitivity
Definition
Response to Ag-Ab complex
IgM & IgG stick to blood vessels or tissue activating C & neutrophils
Activated 3-8 hrs
Term
What type of hypersensitivity is the reaction to tuberculosis?
Definition
Type 4
mediated by t-cells & macrophages
Term
Steps in a clinical encounter
Definition
1. Patient History
2. Physical Examination
3. Investigation plan
4. Management plan
Term
What is the UUT? LUT?
Definition
Upper Urinary Tract=kiney & ureter
Lower Urinary Tract= Urinary bladder & urethra
Term
Common community acquired UTI pathogens
Definition
1. E. coli
2. S. Saprophyticus
3. Proteus miravilis
4. Klebsiella, Enterobacter, Serratia, Pseudomonas aeruginosa
Term
Hospital acquired UTI pathogens
Definition
1. E. coli
2. Klebsiella, enterobacter, serratia, Pseudomonas aeurinosa
3. GPC
4. Proteus mirabilis
Term
Predisposing factors for UTI
Definition
Anything that
Disrupts of urine flow
Preventscomplete emptying of bladder
Promotes microbial access
Term
Virulence factors of UTI E. coli
Definition
O & K serotypes
-Pathogenicity island
-P fimbriae
-Capsular acid polysaccharid to resist phagocytosis
-Membran active cytotoxins
Term
VF of S. saprophyticus
Definition
Adherence to uroepithelium
Microbistatic to GP & GN
Urease-ultimately increases pH cause stone formation allowing more attachment sites for pathogens
Term
P. mirabilis
Definition
Flagella
Urease
Term
Urethritis
Definition
LUT
-Dysuria(painful urination)
Term
Cystitis
Definition
LUT Bladder
-Rapid onset of dysuria;^urgency/frequency
-Cloudy urine(pus or bacteria);blood
Term
Prostatitis
Definition
LUT Prostate
-dysuria, ^frequency, low back pain, fever
Term
Pyelonephritis
Definition
UUT Renal parencyma
-Cystitis+more sever FEVER
-Septicemia, loss of renal function
Term
How to collect urine samples
Definition
Voiding(midstream)
Urinary catheter
Suprapubic bladder aspiration
Term
How do you distinguish cystitis from pyelonephritis?
Definition
Pyelonephritis includes sever fever
Term
What is consider clinically significant bacteriuria?
Definition
10^5 cells
Term
What MO helps protect the vagina & how?
Definition
Lactobacili because it secretes acid=lower pH=barrier against infection
Term
Incurable STD's
Definition
HumanPapillomavirus
Herpes Simplex Virus
HIV
Haemophilus ducreyi
Term
Human Papilloma Virus
Definition
HPV-Genital warts
-Attach via capsid protein, enter via RME
Pathology-Dyplasia(abnormal growth)
-Associated with cervical neoplasia
Term
Reading HPV PAP
Definition
-Less cytoplasm=more sever dysplasia
-Mildly ^nuclear to cytoplasm ratio
Term
Chlamydia trachomatis
Definition
Non-gonococcal urethritis
E-Abrasions
A-Receptors on host cell, parasite-induced endoytosis
S-asymptomatic or urethritis
C-infertility also PID, ectopic pregnancy
txt-tetracycline etc
Term
Candida albicans
Definition
Yeast infection
-Part of normal microbiota
T-disruptions to bacterial vagina community results in overgrowth with yeast
S-UTI, burning/cottage cheesy discharge
Balanitis(inflammation of glans penis)
txt-antifungal
Term
Trichomonas vaginalis
Definition
Vaginitis-Protozoa
E-Vagina in women; Urethra/Prostate in men
S-Vaginitis, yellow/green frothy discharge. Rise in vaginal pH
txt-metranidazole
Term
Herpes Simplex Virus types 1 & 2
Definition
Genital Herpes
E-Membrane fusion
P-Causes host cells to fuse together forming giant cells.
S-Genital lesion vesicles->ulcer w/tender, swolen nodes, fever, headache, malaise
-Remains latent in root ganglion
-Can reactivate due to stress, trauma or sun
Term
Neisseria gonorrhoea
Definition
Gonorrhea
-Women have 20% chance of passing; Men 50-90%
E-Mucous membranes
A-Common pilus, Opa proteins. Invade non-ciliated e cells
P-LPS & Enzymes
-Neonatal blindness
TXT-Treat for gonorrhea (Cefixime & Ciprofloxacin) & Chlamydia
Term
AIDS/HIV
Definition
Disease of immune cells-CD4(Macrophages & Th)
Term
Treponema pallidum
Definition
Syphilis
E-abrasions
S- Chancre 2-4 weeks postinfct
Primary-bacteria multiply in nodes causing swelling
Seconary- Bacteria multiply causing lesions. Most cured some become latent
Tertiary-Host cell-mediated response causes progressive destruction of neuro-, cardio-, skin, and joints
Txt-arsenic, penicillin,
Term
Gastritis
Definition
-Inflammation of the stomach
-Pain in upper abdomen
-Bleeding
Term
Gastroenteritis
Definition
-Inflammation of stomach & intestines
-Diarrhea, nausea, vomiting, crampy abdominal pain
Term
Colitis
Definition
Intestinal syndrome that primarily involves the colon or large intestines
Term
Enterocolitis
Definition
Inflammation of mucosa of both large & small intestine=dysentery-diarrhea often contains blood & mucus
Term
Hepatitis
Definition
Caused by liver damage
Patients become jaundiced due to bilirubin build up in the body
Term
How do pathogens cause disease in the GI tract?
Definition
1) Action of toxins
2) Adherence to & effacement of microvilli=>inflammation
3) Invasion of intestinal epithelial cells
Term
Enterotoxin
Definition
Results in net secretion w/out intestinal damage
Term
Cytoskeleton-altering toxin
Definition
Alters cell shape, may injure cells but not lethal
Term
Cytotoxin
Definition
Causes cell damage and ultimately cell death
Term
Neural toxin
Definition
Alters smooth muscle activity in intestines
Term
What causes bacterial food poining?
Definition
Ingesting preformed toxins; not infections
Term
Bacteria responsible for food poisoning
Definition
Clostridium botulinum-botulism.

Staphylococcus aureus-most common. Starts 30 mins-8hrs post ingestion. Resolves in 24 hrs.

Bacillus cereus-Emetic. Starts 1-5hrs after ingestions. Lasts 1-6 hrs
Term
Pathology of Vibrio cholera
Definition
S-Contaminate water
P-1. Ingest large numbers>10^8
2. Flagella allows Vibrio to reach epithelial cells
3. Attachment by way of fimbriae to receptors on brush border & crypt cells of small intestine
4. Damage due to production of CXT(A & B subunits). Disrupts adenylate cyclase. CXT=enterotoxin, neurotoxin, & cytotoxin
5.Secretion of large quatities of Cloride ion ino intestine. Water and sodium ion follow=hypersecretion of fluids & electrolytes
Term
Symptoms of Cholera
Definition
Extreme diarrhea, rice water stool
Dehydration & electrolyte imbalance=cardiac failure
Txt-Fluid & electrolyte replacement
Term
What mechanism do ETEC(Enterotoxigenic E. coli) and B. cereus use to cause disease?
Definition
Both colonize epithelial surfaces of small intestine & then release toxins. Do not enter cells.
Term
What mechanism does Shigella use to cause disease?
Definition
Atrach to and enter epithelial cells. Multiply intracellularly & destroy(efface) mirovilli of epithelial cells and induce diarrhea
Term
Pathology of Shigella
Definition
S- Contact w/feces from infected person
P-1. descending infection of intestine. Small intestine then colon.
2. Capsule, secretes enterotoxin=watery diarrhea
3. Adhere to cells of colon using Outer membrane proteins
4. Use M cells of GALT and enterocytes to transport Shigella across intestinal epithelium using endocytosis.
5.Escape from phagolysosome
6. Triggers macs to produce IL-1 also triggers apoptosis
7. IL-1 induce inflammation & stimulates edema & extravasation of neutrophis across epithelial barrier
8. Movement of PMNs destroys barrier allowing shigella to move across in mass
9. Further prod. of cytokines & intense inflammation w/destruction of epithelium=>ulcerations=>blood in stool
Term
Symptoms of Shigella infection
Definition
Blood and pus filled diarrhea
Self limiting 2-3 days
Term
What other baacteria share the disease mechanism of Shigella?
Definition
EHEC
Yersinia enterocolitis
Entamoeba histolytic
Rotavirus/Norwalk virus
Term
Salmonella enteritidis, S. typhmuium
Salmonella typhi, paratyphi
Definition
Salmonellosis
Typhoid fever
Pathology:
1. Ingest lots of cells
2. Attach to fibronectin of epithelial cells of small intestine
3. Transported by M cells to GALT
4. Invade gut wall=ulcers adn hemorrhage. Spread to intestinal lymphatics & are phagocytized by macs
5. Produces toxin that ^cAMP & fluid secretion=loose, watery diarrhea & nausea
6. Causes influx of PMN that confines infection to GI
7. OR influx of macrophages which resuls in systemic spread.
Term
What mechanism do S. enteritidis & S. typhi use to cause disease in the GI?
Definition
Attaches, enters & multiplies in deep tissues that are normally sterile-submucosal or subepithelial tissues sometimes will spread systemically
Term
What mechanism do Hepatitis A virus, Reoviruses & Enteroviruses use to cause disease in the GI?
Definition
Attaches, enters & multiplies in deep tissues that are normally sterile-submucosal or subepithelial tissues sometimes will spread systemically
Term
Character of Meningitis
Definition
High fever, headache, stiff neck
Term
How do MO get to the CNS?
Definition
1. From the bloodstream-cross the BBB (Bacterial meningitis)
2. From peripheral nerves (Herpes, VZV, rabies)
3. Invasion from bone/sinuses/middle ear
4. Trauma
Term
Encephalitis
Definition
Acute febrile illness
Changes in mental state
consciousness
behavior
Term
Bacterial Meningitis
Definition
Acute-nearly always fatal

Neonates: E.coli, Group B strep
1mo to 5 yrs: Haemophilus influenzae type B
5 to 40 yrs: Neisseria meningitidis
30 and over:S. pneumoniae
Term
Viral meningitis
Definition
Self-limiting/non-fatal
1. Enteroviruses
2. Arboviruses
3. HIV
4. HSV-2
Term
CSF of bacterial meningitis vs viral
Definition
Bacterial-elevated:neutrophils, protein. Decreased: glucose

Virus
Elevated:lymphocytes, protein.
Normal glucose
Term
Viral encephalitis
Definition
Very severe
1. Arboviruses
2. HSV-1
3. Eneroviruses, mumps
4. Rabies(Rhabodovirus)
Term
Protozoan encephalitis
Definition
Amebic encephalitis-Naegleria fowleri
African Sleeping Sickness-Trypanosoma
Term
Abscess
Definition
Localized collection of pus
Term
Why are MOs in abscesses difficult to treat with antimicrobial agents?
Definition
1. Microbes aren't multiplying
2. Chemical nature of pus interferes with action of some antibiotics
3. Hard to reach site due to lack of vessel penetrations
Term
Scalded skin syndrome
Definition
Strains of S. aureus with lysogenic phages
Causes splitting in deep layers=40% of outer skin layers are lost=loss of body fluid, high fever, and bacteremia
Term
Nectrotizing fasciitis/Flesh eating Strep
Definition
GAS infected by phage
Subdermal tissues
2 toxins-Pyrogenic toxin A: superantigen-IL2
Exotoxin B-destroys tissues by breaking down protein 1in/hr
Term
Exanthems
Definition
Viral diseases resulting in skin rashes
Term
Measles
Definition
Rubeola virus
Term
Scarlet Fever
Definition
s. PYOGENES
Term
German measles
Definition
Rubella virus
Term
Disease 5/Erythema infectiosum
Definition
Parovirus B19
Term
Diseae 6/Roseola infantum
Definition
Human Herpesvirus 6
Term
Most dangerous pathogen of burn damaged skin
Definition
P. aeruginosa
GNR/Ox+
Term
Sites of action of antimicrobials
Definition
1. Cell wall synthesis
2. Cell membrane function
3. Nucleic acid synthesis or replication
4. Bacterial ribosome and protein synthesis
5. Metabolic pathways
Term
Ciprofloxacin
Definition
Quinolline
DNA replication
Term
Sulfamethoxazole
Definition
Sulfonamide
Antimetabolites
Term
Tetracycline
Definition
Tetracyline
Protein synthesis
Term
Gentamicin
Definition
Aminoglycoside
Protein synthesis
Term
Cephalothin
Definition
Beta Lactam
cell wall synthesis
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