• Food Poisoning

• Scalded Skin Syndrome

• TSS Syndrome

• Furuncle, Carbuncle

• Bacteremia, Osteo­myelitis, Endocarditis

GRAM(+) COCCI in clusters

•  Catalase(+)

•  β-HEMOLYTIC — Only at 4°C

•  COAGULASE(+)

•  Hot-Cold Hemolysin Test: β-Hemo­lysin lyses at 4°C

•  Mannitol-Salt Agar for fecal spec­imens

• Coagulase

• Exfoliatin

• TSS-Toxin

• Protein-A (Type-IV Hyper­sensitivity)

• Ribitol Phosphate Peptido­glycan (Type-I Hypersensitivity)

Staphylococcus Saprophyticus

•  Symptomatic UTI’s. Selectively adheres to transitional epithelium.

GRAM(+) COCCI in clusters

•  Catalase(+)

•  Coagulase (-)

•  Non-Mannitol Ferment­ing

Staphylococcus Epidermidis

GRAM(+) COCCI in clusters

•  Catalase(+)

•  Coagulase (-)

•  Non-Mannitol Ferment­ing

•  Surface Glycocalyx

Bacillus Anthracis

ANTHRAX: Zoonotic, cattle

•  Cutaneous eschar (malig­nant pustule)

•  Pulmonary Anthrax

•  GI Anthrax (other coun­tries)

GRAM(+) ROD, large with square end

•  Zoonotic

• Penicillin-Susceptible — string of pearls formation

• γ-Phage susceptible

•  Methylene blue stain shows thin capsule

•  Poly-d-Glutamic Acid Pro­tein Capsule

Cattle Vaccine: At­tenuated strain

Bacillus Cereus

•  Food Poisoning: Re­fried beans and rice

GRAM(+) ROD

• Penicillin-Resistant — chains of rods

• Emetic Toxin (early vom­it­ing)

• β-Lactamase

Bacillus Subtilis

GRAM(+) ROD

TULAREMIA: Zoonotic, rabbits

•  Ulcero­glandular, oculo­glandular, typhoidal, pneu­monic

GRAM(-) ROD: Cocco­bacillus

•  Cystine Agar Required — notify lab

• 3 days to culture.  Longer than usual

• Intracellular parasite of macro­phages

GRAM(-) ROD

• Special transport medium to protect handlers.

• Fibrinolysin to dis­solve the clot.

• YOP’s

•  Scarlet Fever

•  Pyoderma (Impetigo, Erysi­pela)

•  Pharyngitis

• Bacteremia

• Non-Suppurative: Rheumatic Fever, Glomerulo­nephritis

GRAM(+) COCCI in chains of 8 to 4

•  BACITRACIN-SENSITIVE

• CATALASE (-): Does not bubble H₂O₂ in water.

• Todd-Hewitt Broth shows diffuse turbidity down side of tube

• Colonies go from Mucoid (cap­sule) ———> Smooth (capsule breaks down) ———> Rough (pro­tein)

• ASO-Test identifies Strepto­lysin-O

• Superantigen Erythro­genic Toxin A (SEA) causes TSS-Like Syndrome

• Erythrogenic Toxin causes Scarlet Fever.

• Streptolysin O

• M-Protein: Immuno­genic, protective anti­bodies. 85 types.

• DNAse Type-B: Diagnostic for non-suppurative sequelae

GRAM(+) DIPLOCOCCI

• BACITRACIN-RESISTANT

• β-HEMOLYSIS: Small zones

•  CAMP Test: Mix with Staph and it aug­ments the zone of β-Hemo­lysis

• 5 serotypes.  Type III associ­ated with meningitis.

• Type-III capsular antigen is associated with meningitis.

Major pathogen of horses

GRAM(+) COCCI

• ASO-Test identifies Strepto­lysin-O

• Streptolysin O

• Streptokinase: Antigenically distinct from Strep A.

Streptococcus Bovis

• Respiratory

GRAM(+) COCCI

• CATALASE (-)

• α-HEMOLYTIC: Green, partial hemolysis

Enterococcus Faecalis

• Complication of chole­cystitis.

GRAM-VARIABLE COCCI

• CATALASE (-)

• Grows in the presence of bile.

• Blood agar with bile and 6.5% NaCl

•  Cellulitis

•  Synovitis

GRAM(+) COCCI

• Streptolysin O

• Streptokinase

•  Periodontal Disease opportunistic pathogen

GRAM(+) COCCI

• CATALASE (-)

• α-HEMOLYTIC

PNEUMONIA

• Rusty Sputum

• Sudden onset, with res­olution by crisis

• Pericarditis, Empyema, Pleurisy

• Bacteremia

GRAM(+) DIPLOCOCCI, Lancet-Shaped

• Very large capsule = colo­nies with halo.

• Autolysis = middle of colony sunken in.

• Serology: CIE

• Thick Capsule.  85 types; some are bacteremic.

• Amidase causes autolysis

• Pneumolysin-O released upon autolysis: cytotoxin and anti-PMN

• Forssman Antigen: Inhibits amidase and autolysis.

•  Pneumo-Vac Vac­cine: Only the most virulent (bacter­emic) blood groups.  Given to old, Diabetic, HIV, splenectomy, COPD.

•  INFANTILE MENIN­GITIS —  #1 cause in kids 6-24 months

• Epiglottitis

• Cellulitis

• Bacteremia

GRAM (-) ROD, Short Pleo­morphic.

• Types a-f: Type-B is most virulent.  There are also non-typable strains

• Chocolate Agar

•  Absolute Growth Require­ments: Hemin Precur­sor and NAD

• Filde’s Agar: enzymatically lysed RBC’s.

• Satellite Growth around Staph Aureus

• Quellung Reaction against type-B

•  LOS Coat: High molecular weight is more serum-resistant.

• Capsule: Polyribitol phos­phate.  Antibodies are protec­tive; infants susceptible once maternal antibodies are gone.

• IgA Protease

• β-Lactamase Peni­cillin Resistance

•  DPT Vaccine con­taining Hib-conjugate — Diph­theria toxoid plus poly-ribitol phos­phate.

WHOOPING COUGH: Bugs infect cilia of upper airway

• Bugs should be col­lected during Catarrhal Stage of infection

GRAM (-) ROD, Pleomorphic.

OBLIGATE AEROBE

• Collect with nasopharyngeal swab that contains no cotton.  Specimen inoculated at bed-side

• Bordeau-Gangeau Plate required for culture — must notify lab

• Toluidine-blue on gram-stain

• Direct-FA can be done on culture only.

•  Filamentous Hemagglutinin (FHA): Sticks to cilia

• Capsule

• Pertactin

•  DPT Vaccine at 2, 4, and 6 months.

• Initial shots are methiolate-killed whole organisms

• Boosters at 15 months and 6 years: Pertussin toxoid + FHA

DIPHTHERIA:

• Bull neck

• Pseudomembranous Necrosis of throat

GRAM (+) RODS, Slender

• Blood-Tellurite Agar spe­cific for Diphtheria and Staph

•  Coagulated Serum Agar used to test for presence of toxin, which will show creamy colonies

• Tox-gene is phage-mediated and regulated by genome. Only activated by absence of iron.

• Diphtheria Toxin binds to EL-2 to stop protein synthesis.  Deadly once inside the cell.

DPT Vaccine

• Formalin-inacti­vated toxoid, with alum added

• Shick Test used to determine which vaccine to give.

•  Alcoholic, Malnour­ished PNEUMONIA.  Focal lung abscesses

• Bacteremia

• Wound infections

GRAM(-) ROD

LACTOSE (+)

• Thick Capsule = extremely mucinous

• Enterotoxin

• Endotoxin

LEGIONNAIRE’S DIS­EASE

•  non-communicable

• Dry, non-productive cough

• Pulmonary fibrinous exudate.  Multifocal le­sions

• Toxemia

• Pontiac Fever is milder form

GRAM(-) ROD

•  Facultative Intracellular Parasite of PMN’s

• 14 Serotypes.  Group 1 is most common

• Catalase (+)

• Dieterle Silver Stain.  Does not stain otherwise.

• Direct-FA for Group 1

• CYSTEINE absolutely re­quired for culture — notify lab!

• Culture takes 3-5 days.

• Facultative Intracellular Para­site

• Catalase

TUBERCULOSIS

• Very small number needed to infect

• Hilar lymphadenopathy

• Granulomas in lung

• Miliary Tuberculosis

ACID-FAST ROD

• Obligate Intracellular Para­site

• Strict Aerobe

• N-Acetylcysteine will free bugs from macrophages

• Culture takes 3 to 8 weeks!

• Lowenstein-Jensen Medium: inhibit normal flora, plus penicillin

• Liquid Bactec is faster method

• Catalase, Peroxidase

• Cord Factor = virulence

• Wax-D is an adjuvant

• Siderophore: Exochelin + Mycobactin

• Tuberculin: antigenic

•  Multi-Drug Re­sistance (MDR) is a problem

• PPD Skin Test: > 10 mm is positive; < 5 is negative.

• BCG Vaccine mostly in other coun­tries — live attenu­ated bugs.

• Isoniazid is popu­lar drug

ACID-FAST ROD

• Obligate Intracellular Para­site

• Strict Aerobe

ATYPICAL MAC

Pulmonary Disease with single cavitation.

ACID-FAST ROD

• Obligate Intracellular Para­site

• Group 1 MAC: Photochromo­genic.

ATYPICAL MAC

ACID-FAST ROD

• Obligate Intracellular Para­site

• Group 1 MAC: Photochromo­genic

ACID-FAST ROD

• Obligate Intracellular Para­site

MAI

•  Oral portal of entry ———> GI-Tract ———> Bacteremia

• Prevalent with HIV

ACID-FAST ROD

• Obligate Intracellular Para­site

ATYPICAL MAC

ACID-FAST ROD

• Obligate Intracellular Para­site

ACID-FAST ROD

• Obligate Intracellular Para­site

LEPROSY

• Tuberculoid Leprosy

ACID-FAST ROD

• Has never been grown in culture

• Can be harvested in arma­dillos or mouse footpads.

• Phenolic glycolipid is key antigen

Yersinia Enterocolitica

• Watery Diarrhea

• Mesenteric Adenitis (5-15 yrs old)

• Terminal Ileitis (15-20 yrs old)

• Diarrhea

• Enrichment broth used before collecting, due to low number of collecting organ­isms.

• Invasin Gene

• YOP-1, including Mannose-resistant hemagglutinin

• Yad-A adherence protein

• Arithrotigenic Factor: for HLA B27 arthritis

Campylobacter Jejuni

•  Invasive Gastro­enteritis

GRAM(-) ROD, Wavy

MICROAEROPHILIC

MOTILE

• High Incubation Temperature: 42°C —  must notify lab

• Antigenic Diversity

• Enterotoxin: Heat-labile, stim­ulates cAMP.

Campylobacter Fetus

• Bacteremia, going to meninges, lungs, and joints

• Suppurative (early) and Rheumatoid (late) arthri­tis

GRAM(-) ROD, Wavy

MICROAEROPHILIC

MOTILE

• Campy Agar

• Low Incubation Temperature: 25°C —  must notify lab

• Facultative Intracellular Para­site of vascular endothelial cells.

• Antigenic Diversity

• Protein Capsule

Helicobacter Pylori

GRAM(-) ROD, Wavy

MICROAEROPHILIC

MOTILE

•  NON-LACTOSE FERMENT­ING

• CATALASE (+)

•  Normal Incubation Temper­ature: 28°C

• Campy Agar

• Urea Breath Test: Breathe out radiolabeled C.

• Flagellum

• Mucinase

• Catalase

• Oxidase

Pseudomembranous Colitis

• Endogenous infection: antibiotics

GRAM(+) ROD

• Exotoxin-A: Damages intest­inal mucosa

High relapse rate to treatment

Escherichia Coli

• EPEC: Traveler’s Di­arrhea

• ETEC: Watery Diar­rhea

• EIEC: Dysentery

• EHEC: Hemolytic Ure­mic Syndrome (HUS)

GRAM(-) ROD

•  LACTOSE-FERMENT­ING

•  MOTILE

•  MANNOSE-SENSITIVE HEMAGGLUTININ (F1)

• F2-F10: Pili antigens are Mannose-Resistant

• Labile Toxin (LT): Kicks out the water (cAMP).  In small intestine.

• Stable Toxin (ST): Prevents the water from coming back in (cGMP).  In small intestine.

• Verotoxin: (EIEC) Shiga-Like toxin is cytotoxic and works in the colon.

• Invasin

Shigella

DYSENTERY — ulcer­ative colitis.

GRAM(-) ROD

•  NON-MOTILE

• Hemolysin

• Actin-polymerization mechan­ism to get into other cells.

Salmonella Enterocolitica

Enterocolitis: Non-bloody diarrhea

• Large infective dose

GRAM(-) ROD

•  MOTILE

•  NON-LACTOSE FERMENT­ING

• MANNOSE-SENSITIVE HEMAGGLUTININ

•  High antigenic diversity.

•  Selective Medium includ­ing bile and lactose.

• Flagellum (H antigen)

• Polysaccharide (O Antigen)

• Capsule (K Antigen)

•  Pili: Mannose-sensitive hemagglutinins

• LPS Endotoxin

• Enterotoxin similar to E. Coli

• Cytotoxin in colon

Salmonella Typhi

TYPHOID FEVER

• Constipation

• Then bacteremia, sus­tained fever

• Rose-spot rashes

• Diarrhea

• Carrier state for up to a year after resolution

GRAM(-) ROD

•  MOTILE

•  NON-LACTOSE FERMENT­ING

•  Vi Capsular Antigen: Anti­phagocytic, serum-resistant.  Enhances survival inside mono­cytes.

•  Endotoxin

• Flagellar Antigen: Biphasic expression

• Outer Membrane Proteins: enhances resistance to chlorin­ating agents inside monocytes.

May need cholecyst­ectomy.

TAB Vaccine: For travelers, short-term passive protection against Vi antigen.

Vibrio Cholerae

CHOLERA: Profuse non-invasive rice-water diarrhea

GRAM(-) ROD, comma-shaped with long flagellum

•  MOTILE

•  NON-LACTOSE FERMENT­ING

• OXIDASE (+)

• HALOPHILIC

• Transport medium contains pH > 8 to supress other flora.

• Darkfield stain only.

• Serology test for O1 Sero­type to test for Tox-gene

• Polar flagellum

• Mucinase

•  Live attenuated vaccine provides short-term protec­tion.

• Oral rehydration therapy.

Vibrio Para-haemolytic­us

•  Raw shellfish

• high infective dose

• Self-limiting diarrhea

GRAM(-) ROD

•  HALOPHILIC

• Salty (3% NaCl) selective medium

Escherichia Coli

GRAM(-) ROD

•  LACTOSE-FERMENT­ING

•  MOTILE

•  MANNOSE-SENSITIVE HEMAGGLUTININ (F1)

• Mid-stream clean catch

• P-Antigen: Correlates with likelihood of Pyelonephritis (Pili antigen 2-10).

• K-Antigen (Capsule): As­soci­ated with adherence to trans­i­tional epithelium.

Proteus Vulgaris

•  10-15% of Hospital Acquired UTI’s

GRAM(-) ROD

•  UREASE (+)

• Urease: alkaline urine can lead to calculi and kidney stones

• Lots of peritrichous flagella

Proteus Mirabilis

GRAM(-) ROD

•  UREASE (+)

Pseudomonas Aeruginosa

• UTI’s — 3^rd most com­mon cause

• Burn infection

• Opportunistic pneumo­nia, especially in CF pa­tients.  Micro-abscesses seen in lungs.

• Otitis Externa

GRAM(-) ROD

•  STRICT AEROBE

•  NON-FERMENTING of all sugars

• OXIDASE (+)

• Juicy-Fruit Smell

•  Blood Agar: β-Hemolytic blue-green colonies.

• Pyocyanin: against Staph Aureus

• Pyoverdin: Ciliastatic, ac­quire iron

• Flagella: Adhere to urinary tract

• Pili: Adhere to respiratory tract

• Exotoxin-A: Binds to EL-2, stop protein synthesis.

• Exotoxin-S

• β-Hemolysin

• Alginate: In CF patients

• Elastase

Neisseria Gonorrhea

GONORRHEA

• Bacteremia leading to septic arthritis — #1 cause in young adults

GRAM (-) DIPLOCOCCI, Kidney-shaped

• CATALASE (+)

• OXIDASE (+)

•  GLUCOSE-FERMENT­ING

•  NON-MALTOSE FERMENT­ING

• Facultative Intracellular Parasite

•  Stain is only useful on ure­thral exudate — not swab.

•  PI: Complexes with PIII to form Porin

•  PII: Adhesin, autoagglut­ination

•  PIII: Complexes with PI to form Porin

• LOS

• IgA Protease, two types.

• Catalase, Superoxide Dismutase, Peroxidase

• By law, proph­ylac­tic treatment for neo­natal conjunctivitis.

CHANCROID:

• Painful

• Purulent Exudate

GRAM(-) ROD

SYPHILIS:

Primary Syphilis:

• Painless

• Serous Exudate

• Indurated

Secondary Syphilis: Rash

SPIROCHETE

• Cannot be cultured

• RPR Test: IgG against cardiol­ipin, lecithin, and cholesterol­

• FTA Test: Antibody against the bug itself

Hyaluronidase.

Neisseria Meningitidis

MENINGITIS

• #2 cause of infantile meningitis (6 months - 24 months)

GRAM (-) COCCI

•  CATALASE (+)

•  OXIDASE (+)

•  GLUCOSE-FERMENT­ING

•  MALTOSE-FERMENT­ING

• Serotypes: Type-B is most virulent — we don’t make antibodies to it.

• Quellung Reaction to look for Type-B

• CIE, Latex Agglutination

• Capsule: Thick and anti­phagocytic

• LPS: Induces Shwartzman reaction, leading to rash and necrosis.

• Pili

• IgA Protease

Vaccine for military recruits, not includ­ing Type-B.

BRUCELLOSIS, UNDULATING FEVER

GRAM (-) ROD: Cocco­bacillus

CATALASE (+)

OXIDASE (+)

• Catalase

• LPS

LISTERIOSIS

• Neonatal and in-utero disease.

• Tropic for CNS

• Bacteremia: meningitis and endocarditis

GRAM (+) ROD

•  Facultative Intracellular Parasite of Macrophages

•  β-Hemolytic

Blood Agar: Small colonies, narrow zone of β-hemolysis.

• Can grow in cold

• Listeriolysin-O: Cytotoxic, hemolytic

• Actin polymerization to infect neighboring cells

LEPTOSPIROSIS

• Liver, kidneys, CNS

• Tropic for endothelial cells in the CSF

SPIROCHETE

•  β-Hemolytic

Dark Microscopy: Two axial filaments per pole with hook at end.

•  Cell Wall Lipids = 25% of dry weight of cell.  LPS-like symptoms

• Hemolysin

RELAPSING FEVER

SPIROCHETE

MICROAEROPHILIC

Dark Field Microscopy: 15-20 axial filaments per pole.

Antigenic Shift

LYME DISEASE

Spread by Dear Tick

• Erythema Chronicum Migrans

SPIROCHETE

MICROAEROPHILIC

Dark Field: 7-11 flagella at each pole, but no axial fila­ments.

Bugs probably killed by Ab + Complement (few PMN’s).

Bacteroides Fragilis

(Enterobacteriaceae)

• PID

• Peritonitis

STRICT AERO­TOLERANT ANAEROBE

CATALASE (+)

Anaerobic Transport Medium required

• Direct FA

•  Capsule

• LPS, not as bad as E. COLI

•  GAS GANGRENE: Type-A

• Necrotizing Enteritis: Type-C

GRAM (+) ROD, Spore-Form­ing

STRICT AERO­TOLERANT ANAEROBE

• Stain: Rods with square ends and a capsule.

• Egg-Yolk Agar: Lecithin is present to test for lecithinase.

• Very fast replicating

• Alpha Toxin: Lecithinase, responsible for zone of incomplete hemolysis

• Beta Toxin: Cytotoxin, responsible for necrotizing enter­itis.

• Theta Toxin: Oxygen labile hemolysin, responsible for smaller zone of hemolysis.

Antibiotics.

GRAM (+) ROD, Spore-form­ing

STRICT ANAEROBE

Diagnosis is clinical — not by culture

•  Alum-precipitated Toxoid given at 2, 4, 6, 18 months

• Boosters every 10 years are ammonium-ppt

GRAM (+) ROD, Spore-form­ing

Alum-ppt toxoid avail­able for lab work­ers.

Coxiella

Rickettsia ricketstii

Egg or Tissue Culture

•  LPS

• Phospholipase: Helps bugs get into endothelial cells.

Chlamydia Trachomatis

CHLAMYDIA

•  Lymphogranuloma Venereum

OBLIGATE INTRA­CELLULAR PARASITE

• Stains brown with Iodine

• No Peptidoglycan Layer

A-C: Keratoconjunctivitis

D-K: Chlamydia

•  Iodine test for inclusion bodies containing glycogen — stains brown

• Take scrapings and look for inclusion bodies in epithelia.

•  ATPase

•  ATP-ADP Translocase

•  Cylindrical Projections to get nutrients.

Tetracycline

Chlamydia Pneumonia

OBLIGATE INTRA­CELLULAR PARASITE

Chlamydia Psittaci

OBLIGATE INTRA­CELLULAR PARASITE

• No Peptidoglycan Layer

• Iodine Test is negative.

• Indirect FA

Mycoplasma Pneumonia

WALKING PNEUMO­NIA: Monocytic response.  Ciliastatic in upper airway like Whoop­ing Cough.

OBLIGATE INTRACEL­LULAR PARASITE

• Biphasic Enriched Broth/A­gar

• Cholesterol required for Growth

• Cold-Agglutination Anti­body Test: Agglutinates with Type-O blood-group antigen in the cold.

P1 Protein: Adhesin for GI, UG, respiratory epithelia.  Glid­ing motility.

Ureaplasma Urealytica

Urethritis, maybe asymp­tomatic.

OBLIGATE INTRACEL­LULAR PARASITE

UREASE (+)