Microbio Summary

Azhar Gangat (ASUMS) Organism

Staph aureus

Characteri stics

G+

cocci

β hemolytic

catalase +

coagulase +

salt tolerant

mannitol fermenter

1

Reservoir/ Transmission (T)/ Predisposing Factors (PF) NF:

Virulence Factors (VF)/

Clinical Findings

Pathogenesis (TX) VF:

PYOGENIC (abscess):

nasal mucosa,

protein A,

skin

surface receptors (eg. teichoic acid), microcapsule,

skin infections (+otits externa),

T: hands, sneezing, ham/canned meat, custard pastries, potato salad

PG layer 2

sepsis, endocarditis, osteomyelitis, arthritis, post-surgical wound infections,

TX:

pneumonia,

PF: surgery,

enterotoxin,

abscess in any organ

break in skin, foreign body (eg. tampons, sutures), neutropenia,

TSST,

IV drug abuse, CGD 1

Diagnosis

exfoliatin, leukocidins (α toxin, P-V leukocidin), enzymes 3

TOXIGENIC (superantigen): food poisoning (1-8 hrs), toxic shock syndrome, scalded skin syndrome 4

the most common cause of skin infections, food poisoning, osteomyelitis, 2nd for otits externa

blood agar

mannitolsalt agar

Azhar Gangat (ASUMS) Staph epidermidis

G+

cocci

2

NF:

VF:

skin,

glycocalyx

mucous membranes

endocarditis (within 2 months of surgery, after→ S. viridans) arthritis, osteomyelitis,

catalase +

coagulase –

novobiocin sensitive Staph saprophytic s

sepsis in neonates,

PF: prosthetic heart valves and joints, intravenous catheters

peritonitis in renal failure

nosocomial

G+

cocci

urinary tract infections (especially in sexually active young women)

community acquired

2nd to E. coli in causing community acquired UTI

catalase +

coagulase –

novobiocin resistant Strep pyogenes

G+

NF:

Antigens:

human throat, cocci

catalase –

skin

T: respiratory droplets,

PYOGENIC: phrayngitis,

M Protein

impetigo,

(SPAM)

Invasive

Strep. Pyogenes Antibody to M Prtn,

necrotizing fasciitis, cellulitis,

produce β lactamase

Azhar Gangat (ASUMS) group A

3

direct contact

erysipelas, C Carbohydrate,

β hemolytic (clear zone)

polysaccharid e capsule 16

sepsis, puerperal fever

TOXIGENIC: scarlet fever, toxic shock

bacitracin sensitive

IMMUNE-MEDIATED (non-suppurative): Enzymes:

rheumatic fever,

hyaluronidase,

acute glomerulonephritis

streptokinse,

19

DNase 17

TX: erythrogenic toxin, pyrogenic toxin A, exotoxin B,

2nd most common cause of skin infections after S. aureus

streptolysin O, streptolysin S 18

Strep agalactiae

G+

Colonization:

neonatal septicemia

human vagina cocci PF: catalase –

prolonged (>18

meningitis (in 1st month)

Azhar Gangat (ASUMS)

group B

β hemolytic (clear zone)

bacitracin resistant

hydrolyze hippurate

cAMP test + Strep pneumonia e (pneumoco ccus)

4

hrs) rupture of membranes in women who are colonized with this bacteria,

24

the most common cause of neonatal sepsis and neonatalmeningitis, E. coli is 2nd

<37 wk gestation, children of mothers lacking antibody to group B strep.,

S. pneumonia: adult meningitis

diabetes

T: newborns infected during birth

G+

Colonization:

VF:

pneumonia

cocci

human respiratory tract (no animal)

polysac. capsule,

(with bloody rusty sputum)

lipoteichoic acid,

jelly-like sputum in Klebsiella,

lacentshaped diplococci

pneumolysin, T:

catalase –

respiratory droplets

26

IgA protease 25

otitis media in children, sinusitis in children,

polysac. capsulate d

PF: CASMIR Circulatory problems

αhemolytic

meningitis in adults

Alcoholism

Strep. pneumoniae is the most common cause of: pneumonia,

quelling reaction + (test for swelling of capsule)

blood agar

Azhar Gangat (ASUMS) (green zone, caused by pneumoly sin)

optochin sensitive

5

aSplenia

adult meningitis,

Measles infection

otitis media in children, sinusitis in children

Influenza infection

pneumonia in alcoholics

Respiratory problems S. agalactiae: nenonatal meningitis

bile soluble

Also: purulent bronchitis, corneal ulcer (purulent discharge in conjunctivitis), pericarditis, sepsis

Strep viridians

G+

S. sanguis S. mutans

catalase –

αhemolytic (green zone)

optochin resistant

N F: human oropharynx

fever, heart murmur, anemia, embolic events, malaise , fatigue , anorexia, night sweats & weight loss

PF: damaged heart valves,

urological instrument route: S. faecalis

dental surgery, poor oral hygiene dextran: S. mutans:

bile insoluble

infective endocarditis (oral route):

dental plaque

leads to dental caries

after 2 months of surgery, before→ S. epidermitidis

dental caries

blood agar

Azhar Gangat (ASUMS) Enetrococc us faecalis

G+

NF:

UTI:

human colon

dysuria (painful urination),

catalase – R: group D

γhemolytic (no hemolysis)

growth in 6.5% NaCl or bile, pH 9, 45˚C

urethra, female genital tract

discharge of ulcer

endocarditis (urological instrument route): during medical procedures on GI or U tract: E. faecalis→ blood stream→ previously damaged heart valves→ endocarditis

indwelling urinary catheters,

NF:

Catalase-

γhemolytic (no hemolysis)

fever,

GI or urinary tract surgery,

human colon

group D

↑fear of urination,

Also:

mostly nosocomial

G+

burning urine,

PF:

urinary tract instruments,

S. bovis

6

PF: carcinoma of colon

oral route: S. viridans

can cause intraabdominal and pelvic infection with S.bovis endocarditis: especially in patients with colonic carcinoma

Azhar Gangat (ASUMS)

Neisseria meningitidi s

no growth in 6.5% NaCl G-

oxidase +

kidney bean shaped diplococci

Colonization:

7

VF:

meningitis,

human polysac. nasopharyngeal capsule, area IgA protease,

(the most common cause between the ages of 2 & 18)

chocolate agar (37˚C, 5% CO₂)

LPS T:

32

respiratory droplets

meningococcemia (WaterhouseFriderichsen syndrome) 33

Neisseria gonorrheae (gonococcu s)

capsulate d

13 different serotypes (polysac. capsule):

maltose fermenter G–

eg. A, B, Y, W135 VF:

oxidase +

coffee/kid ney bean shaped diplococci

R: human genital tract (sensitive to dehydration and cool conditions)

glucose fermenter

pili, LOS,

Male:

IgA

urethritis, proctitis,

Other VF’s:

epididymitis

OPA T:

pili

gonorrhea:

sexual contact, Infection of newborns during birth

-dissemination also possible → septic arthritis

POR

Female:

RMP

cervicitis,

FBP

salpingitis,

LIP

PID → sterility & ectopic pregnancy 37

ThayerMartin medium (chocolate agar containing antibiotics )

Azhar Gangat (ASUMS)

8

Newborn: (2-5 days onset) purulent conjunctivitis (opthalmia neonatorum), → blindness

Dissemination:

Moraxella catarrhalis

G–

diplococci

Bacillus anthracis

close relative of Neisseria G+

squareended rod

spore formation

aerobe

capsulate d

the most common cause of septic arthritis in sexually active adults otitis media,

NF: upper respiratory tract

bronchitis, bronchopneumonia (elderly with COPDchronic obstructive pulmonary disease)

R:

VF:

anthrax:

spores in:

capsule

cutaneous (95%),

soil,

(D-glutamase, not polysac.)

pulmonary (4%),

animal skin, animal products (eg. wool, hair),

TX:

contaminated meat

edema factor,

48 exotixins:

lethal factor, T: skin, mucous

GI (1%)

protective antigen

not communicable person-to-person (ie. through respiratory droplets)

blood agar,

mediastin al widening in x-ray

Azhar Gangat (ASUMS) nonmotile

9

membrane,

47

respiratory tract Bacillus cereus

G+

rod

spore formation

aerobic

motile

R:

TX:

rice,

enterotoxins:

-fried rice

other grains

emetic type,

-S. aureus type

diarrheal type

-vomiting

PF:

emetic (1-6 hrs)

-abdominal pain

Reheated fried rice (Chinese restaurants),

diarrheal (18 hrs) -meats, sauces

Held warm (not hot) for long periods

-E. coli/ Clostridial type -watery diarrhea

Affect: GI tract

may cause: eye infections

Clostridium tetani

G+

R:

TX:

soil

Tetanospasmi n (exotoxin):

rod (tennis racket/dru m stick shaped)

PF: wound, skin breakage, skin-popping,

spore formation

infected mother may infect the

-blocks inhibitory mediators (eg. glycine, GABA, glutamic acid)

2nd most common cause of food poisoning after S. aureus tetanus: difficult to culture -spastic paralysis -locked jaw (trismus) -violent muscle spasms -grimace(risus sardonicus) -increased reflexes -respiratory failure

Azhar Gangat (ASUMS)

10

newborn

→death

anaerobic poor blood supply in the necrotic tissue helps its growth

Clostridium botulinum

G+

rod

spore formation

anaerobic

neonatal tetanus: -enter through contaminated umbilicus or circumcision wound

R:

TX:

Adult (2-3 hours):

soil,

-preformed in can

wound botulism:

dust

T: canned/vacuum packed food without sterilization,

-labile (ie. inactivated by heating)

-blocks release of Ach

green beans,

smoked fish,

Infant (2-3 days):

-diplopia,

drug abuse skin-popping ,

-dysphagia, -respiratory muscle failure,

honey for infants R:

TX:

-flaccid paralysis wound infections:

soil

lecithinase

-pain,

(α-toxin):

-edema,

-gas production

-cellulitis,

rod NF: spore formation

-weakness, dizziness, blurry vision, flaccid paralysis

-toxins produced in the gut

mushrooms,

G+

colon, vagina

mouse protection tests

Infant botulism (honey):

peppers,

Clostridium perfringes

-toxins produced at the side of the wound

not cultured,

-cell membrane

-crepitation (gas presence)

blood agar: double zone of hemolysis

egg-yolk agar:

Azhar Gangat (ASUMS) anaerobic

11

T:

damage

also:

war wounds, automobile/mot or accidents,

→ hemolysis

hemolysis, jaundice,

lecithinase presence

blood-tinged exudates →shock & death

septic abortions,

Food Poisoning (8-16 hours):

food contamination

watery (noninflammatory) diarrhea, little vomiting

PF: reheated food, especially meat dishes Clostridium difficile

G+

R:

TX:

human colon

exotoxin A

rod

exotoxin B T:

spore formation

fecal-oral route

PF: anaerobic

antibiotics, chemotherapy

Listeria monocytog enes

G+

rod

especially nosocomial R:

TX:

animals,

listerolysin O:

plants,

-similar to streptolysin O

soil arranged

(add glucose to G protein involved in actin filament polymerizatio n→ depolymerizat ion of actin→ death of enterocyte)

-degrades

3rd most common cause of food poisoning after S. aureus and B. cereus pseudomembranous ELISA colitis tests (presence of yellowwhite plaques on colonic mucosa),

bloody/nonbloody diarrhea (the most common nosocomial cause of diarrhea)

sepsis (granulomatosis infantiseptica),

acute meningitis (after 1-4 weeks),

blood agar

Azhar Gangat (ASUMS) in V or L shapes

T:

tumbling motility

contaminated vegetables,

unpasteurized milk,

animal contact facultative intracellul ar parasite

12 cell membranes

actin rockets: cell to cell movement

Cold Growth:

cold growth

sepsis & meningitis in immunosuppressed,

PF:

abortion,

placenta/delive ry,

premature delivery

renal transplant, β hemolytic

the most common cause of sepsis and meningitis in renal transplant patients and adults with cancer

↓ cell mediated immunity

(narrow clear zone) Corynebact eria diphtheriae

G+

rod (beaded appearanc e)

aerobic

non-motile

-watery diarrhea, fever, headache, abdominal pain, little vomiting -caused by contaminated dairy products & undercooked meats

cheese, cabbage

loves lysosomes

gastroenteritis:

R:

TX:

diphtheria:

human upper respiratory tract

diphtheria toxin:

-inflammation of throat

-inhibits protein synthesis by ADPribosylation of EF-2 (elongation factor)

-thick, grey pseudomembrane (bull neck)

this toxin is also present in

-myocarditis→ arrhythmia

T: air-borne droplets

PF: skin lesion,

-can lead to: -tracheal/ tracheal extension→ airway obstruction

volutin granules stain metachro mat-ically

blood agar

potassium tellurite agar

Azhar Gangat (ASUMS)

Actinomyce s israelii

13

V or L shapes

poor skin hygiene

Pseudomonas

-recurrent laryngeal nerve palsy

G+

NF:

hard, nontender swelling drains pus through sinus tracts

actinomycosis:

rod (long branching filaments)

gingival crevices (oral cavity), female genital tract

cervicofaical (lumpy jaw): -dental trauma, poor oral hygiene

anaerobe

sulfur granules (hard, yellow coloured)

PF:

pelvic form:

upper body lesions/trauma (especially face & neck),

-intrauterine contraceptive device (IUCD)

intrauterine device retention for a long period of time

thoracic: -aspiration (removal) with contagious spread

abdominal: noncommunicable Nocardia asteroides

G+

R: soil,

rod (thin branching filaments)

dust bronchopulmonary: T:

aerobic

airborne, trauma

weakly acid-fast

-surgery or bowel trauma nocaridiosis (pulmonary infections):

noncommunicable

-cough -fever -dyspnea -begins as pulmonary infection and may spread as abscess/ sinus tracts

Azhar Gangat (ASUMS)

14 -immunocompromized : may spread to brain, skin, kidneys

cutaneous/subcutaneo us: -cellulitis -granuloma -ulcer -swelling Mycobacter ium tuberculosis

acid-fast

R:

(mycolic acids)

human lungs

T: rod

respiratory droplets

aerobic

-no toxin production

-causes infection of macrophages and other REcells

-starts with trauma TB: -any part of the body could be affected except teeth -transmission through lymphatics→ lymphadenopathy (matty palpation)

VF: facultative intracellul ar

lipid content, phosphatides, cord factor,

typical mycobact eria

slow growth

sulfatides, PPD 73

PF:

-exported repetitive protein→ prevents fusion of phagosome and lysosome

low grade fever (no chill), night sweat, weight loss, cough with hemoptysis, other signs depending on the organ involved (ie. pneumonia-like symptoms if the lungs are involved)

poverty, UV sensitive

HIV infection, IV drug abuse

also: scrofula

Lowenstei n- Jensen medium

AuraminRhodamin e stain

tuberculin test

Azhar Gangat (ASUMS)

Mycobacter ium kansasii

pathogeni c for guinea pigs atypical mycobact eria

15

T:

lung disease

soil, water

Mycobacter ium marinum

nonpathogeni c guinea pigs T: photochro mogens (yelloworange pigments when exposed to light)

swimming-pool granuloma (fish-tank granuloma):

water (fresh/salt),

-granulomatous, ulcerating lesion in the skin

swimming pool, aquarium,

PF: scuba divers, skin abrasion

Mycobacter ium scrofulaceu m

atypical mycobact eria

T: Oropharynx

infection of draining lymph nodes

scrofula: -granulomatous cervical lymphadenitis -usually in children

nonpathogeni c guinea pigs

scototochr omogens (pigments in dark)

Azhar Gangat (ASUMS) Mycobacter ium avium

atypical mycobact eria

T: soil,

16 chronic pulmonary diseases

water Mycobacter ium intracellular e

MAI: nonpathogeni c guinea pigs

MAI

Mycobacter ium fortuitum

PF: AIDS, cancer,

nonchrom ogens

immunocompromized

(no pigments) atypical mycobact eria

T: soil, water

Mycobacter ium chelonei

Mycobacter ium leprae

the most common bacterial infection in AIDS patients

nonpathogeni c guinea pigs

rapid growth acid-fast

rod

skin, soft tissue infections

PF: immunecompromised, prosthetic heart valves and joints R: human mucosal membrane, skin,

obligate intracellul ar

rarely occurring infection:

superficial nerves

leprosy:

tuberculoid: -fewer lesions

+ lepromine test

-macular (flat) -nerve enlargement (claw hand)

T: slow growth

nasal discharge from untreated leprosy

lepromatous: -numerous lesions

lepromine test

Azhar Gangat (ASUMS) optimal growth at cool temperatu re (30˚C)

17

patients

-nodular -loss of eyebrows -destruction of nasal sputum -paraesthesia (abnormal sensation) -leonine facies

Pseudomon as aeruginosa

G–

R:

LPS:

(ridges & furrows) in normal people:

water

exotoxin A:

loose stool, folliculitis,

T:

-tissue necrosis (especially liver) -inhibits protein synthesis by ADPribosylation of EF-2 (elongation factor)

burnt patients:

rod

aerobic

water aerosols, raw vegetables,

oxidase +

nonferme nter

pyocyanin -blue colour in pus

pyoverdin (fluorescei n) -yellowgreen colour

flowers

PF: nosocomial, extensive burns, chronic respiratory disease (cystic fibrosis), catheterized, immunosuppre sed, anesthesia injections/CSF sampling, swimmers,

odour:

gym goers,

-this toxin is also present in C. diphtheria

pyocyanin: -damages cilia and mucosal cells of respiratory tract

elastase, protease:

eye ulcers

skin infections, ecthyma gangrenosum (black necrotic centre, erythematous-redmargin), eschar, cellulitis (blue-green pus), septicemia (also in AIDS pt’s)

in catheterized patients: UTI

in cystic fibrosis patients: recurrent pneumonias,

MacConke y’s/ EMB agar

Azhar Gangat (ASUMS) grape-like/

contact lenses

corn nacho

18 -help in invasion -histotoxic

septicemia

after CSF sampling/ anesthesia injection: meningitis

swimmers: otitis externa (most common casue), neck down (hot tub) follicles

gym shoes: osteochondritis

contact lens users: corneal infections

Campyloba cter jejuni

G–

rod (curved: comma/S shaped)

R:

TX:

cattle, sheep, cat, dog,

enterotoxin:

intestinal tract of humans

T: polar flagella

microaerocephalic

fecal-oral route

PF: improperly

sepsis caused by P. aeruginosa has >50% mortality rate inflammatory diarrhea: >10 stools/day

-destruction of mucosal surfaces of colon

-bloody

→ blood and pus in stool

-fever

-abdominal pain -malaise

-lasts 3-5 days

most common cause of inflammatory diarrhea,

blood agar

Azhar Gangat (ASUMS)

19

cooked chicken, grows well at 40˚C

motile

2nd most common is salmonella

raw eggs, poultry products,

predisposes to GuillainBarré syndrome:

meat,

-autoimmune disease

milk

-demyelination

oxidase +

Helicobacte r pylori

urease G–

rod (curved)

R: human stomach

T: polar flagella

microaerocephalic

fecal-oral route, oral-oral (communicable ), clustered families

grows well at 37˚C

urease +

G– (weakly)

→ urease → ammonia formation + inflammation →damage to mucosa ↓ this damage predisposes to peptic ulcer and gastritis

ammonia breath

blood agar

gastritis, peptic ulcers, severe upper abdominal pain

helicobacter infection: predisposing factor for gastric cancer

ammonia helps bacterium survive by neutralizing acid

oxidase +

Legionella pneumophil a

attachment to mucosa

R: water: -air

LPS

Legionnaire’s disease (atypical pneumonia) with:

charcoalyeast agar

Azhar Gangat (ASUMS) rod (pleomorp hic)

20

conditioners

-confusion

-water coolers

-non-bloody diarrhea

-rivers

-proteinuria

-streams

-hematuria

iron & cystein required

-cough PF:

-resolves in 7-10 days

Renal transplant

hyponatremia (↓Na)

Alcoholic Cancer

Pontiac fever:

Old age

-flu (fever, soar throat)

Smoker

-no pneumonia

AIDS

T: aerosol from contaminated A/C

noncommunicable Bordetella pertussis

G–

R: humans

rod

encapsula ted

-10 years after vaccination, humans serve as reservoirs

hemagglutinin (FHA)

pertussis (whooping cough):

TX:

catarrhal stage (1-2 weeks)

pertussin (adenylate cyclase),

T: respiratory droplets

tracheal

paroxysmal stage (2-4 weeks)

BordetGengou medium

Azhar Gangat (ASUMS)

21 cytotoxin

convalescence (>3 weeks)

98

E. coli: ADP ribosylation is by Gs protein

Gi protein in B. pertussis Francisella tularensis

G–

R:

tularemia (endemic in the US):

wild animals: rod (pleomorp hic)

rabbits, tick bite:

deer,

ulceroglandular type:

rodents

-fever facultative intracellul ar

-ulcer at bite site

T:

-regional lymph node enlargement

tick bite, aerosols (rabbitskinning),

skinning rabbits:

ingestion (contaminated water, infected meat)

pneumonia

ingestion: typhoidal tularemia

Brucella melitensis (goats)

G–

noncommunicable R: goats,

rod

sheep,

localization in reiculoendoth elial system -lymph nodes

brucellosis (undulant fever):

Azhar Gangat (ASUMS)

abortus (cattle)

zoonotic

22

cattle,

-liver

pigs

-spleen -bone marrow

suis (pig)

T:

acute (cepticemia):

chronic (in older people):

unpasteurized dairy products (goat milk),

102

direct contact to animals, slaughterhouse workers Escherichia coli

G–

rod (motile)

facultative anaerobe

lactose fermenter

glucose fermenter

oxidase –

nitrates to nitrites reduction

NF:

TX:

UTI:

colon,

K polysaccharid e (capsule),

the most common cause of UTI is E. coli, S. saprophyticus is 2nd

vagina, urethra

PF (UTI): strinctures, stones, abnormal urine flow, indwelling urinary catheters

PF (watery diarrhea): poor sanitization of water, fruits/ vegetables contaminated

O antigen (cell wall) -serologic typing, H antigen (flagella)

neonatal sepsis & meningitis: 2nd most common cause after S. agalactiae

Enterotoxigenic (ETEC): TX: heat labile toxin, heat stable toxin E. coli: ADP ribosylation is by Gs protein, Gi protein in B. pertussis

-traveler’s diarrhea (watery) -diarrhea in <3 years old

Enteropathogenic (EPEC): -2nd most common cause of infantile diarrhea after rotavirus

blood agar

EMB (green)

MacConke y’s agar (pink)

Azhar Gangat (ASUMS)

23

with human feces

Enteroinvasive (EIEC): -actin (Jet trails)

verotoxin: PF (bloody diarrhea): 104

undercooked hamburgers,

-bloody/ watery diarrhea

Enterohemorrhagic (EHEC): -bloody diarrhea

raw milk,

-hemolytic uremic syndrome

fallen apples (apple juice)

-hemorrhagic colitis -no fever (present in shigellosis)

Enteroaggressive (EaggEC): -persistent diarrhea -vomiting

105

Shigella disenteriae (severe) sonnei (common)

G–

rod

R:

TX:

human colon

O antigen (cell wall)

(no animals)

-serologic typing facultative anaerobe

glucose fermenter

T: fecal-oral route

fingers

invasion of the cells of distal ileum and colon

dysentery:

blood agar

-fever (>101˚F) -lower abdominal pain -tenesmus (spasms of urogenital region) -first watery, then bloody diarrhea -shallow ulcers

EMB/ MacConke y’s agar -colourles s colonies

Azhar Gangat (ASUMS)

oxidase –

24

food

shigellosis:

feces

-the most severe form of diarrhea (10-15 episodes/day)

flies nitrates to nitrites reduction

Klebsiella

G–

communicable -low quantity needed to cause an infection R: human colon,

rod

upper respiratory tract

large capsule

TX: K polysaccharid e (capsule)

lactose fermenter

glucose fermenter

-thick, bloody, jelly-like sputum

UTI: from own flora in low immunity, respiratory droplets, catheters (nosocomial)

O antigen (cell wall) -serologic typing

LPS:

blood agar

-abscess

-antiphagocyt ic

T: facultative anaerobe

pneumonia:

EMB/ MacConke y’s agar -pink colonies

-nosocomial (catheters)

septicemia: -in immunocompromized

-fever -inflammation

PF:

-shock

diabetes, oxidase –

alcoholism, old age,

nitrates to nitrites reduction Salmonella typhi

G–

chronic respiratory disease R:

TX:

humans (no

K

typhoid fever/ enteric fever

blood agar

Azhar Gangat (ASUMS) rod (motile)

animals)

25 polysaccharid e (capsule)

-rose spots

T: facultative anaerobe

enteritidis typhimuriu m choleraesui s

produce H2S

fecal-oral route from human carriers (gall bladder)

PF: glucose fermenter

O antigen (cell wall) -serologic typing

H antigen (flagella)

↓ stomach acid Vi antigen (typoid)

oxidase – R: nitrates to nitrites reduction

enteric tracts of humans, chickens, turtles

-invasion of epithelium of SI & LI (enteric fever)

T: raw chicken, egg

PF:

( S . typhi/ S. paratyphi):

-constipation

EMB/ MacConke y’s agar -colourles s colonies

-gallbladder inflammation -Vi antigen: multiplication in Payer’s patches→ spread to phagocytes of liver, gall bladder, & spleen → leading to bacteremia -constipation followed by diarrhea

enterocolitis /gastroenteritis (6-8 hours): -inflammation -loose bloody stool -2nd most common cause of inflammatory diarrhea, after Campylobacter

sickle cell anemia septicemia: -in very young/ elderly PF: sickle cell anemia osteomyelitis/ arthritis:

widal test

Azhar Gangat (ASUMS)

26 -followed by pneumonia, meningitis -the most common cause of osteomyelitis in patients with sickle cell disease

PF: aortic aneurysms, infarcts

metastatic abscess: -abscess away from primary origin

Aerobes: Negging Pests Must Breath Nocardia Pseudomonas aeruginosa Mycobacterium TB Bacillus

Anaerobes: A - B – C Actinomyces Bacteroides Clostridium

Capsulated: Some Bacteria Have An Effective Paste Surrounding Membrane Yielding Pseudo Fort, Bypassing Killing Strep. pneumonia Bordetella, Bacteroides H. influenza Anthracis (Bacillus) E. coli

Azhar Gangat (ASUMS)

27

Pasteurella Salmonella Meningitidis (Neisseria) Yersinia Pseudomonas Francisella Brucella Klebsiella

Pneumonia (most common causes): Type Most common (bloody-rusty sputum) Thick, bloody, jelly-like sputum In alcoholics In cystic fibrosis patients (recurrent) Atypical pneumonia (Legionnaire’s disease) After rabbit-skinning Sequel to osteomyelitis Pyogenic infection

Organism S. pneumonia Klebsiella S. pneumonia Pseudomonas aeruginosa Legionella pneumophilia Francisella tularensis non-typhoid Salmonella S. aureus

Meningitis (most common causes): Type Neonatal Adult Between ages 2 & 18 In renal transplant & cancer patients After CSF sampling/ anesthesia injection Sequel to osteomyelitis

Organism S. agalactiae E. coli S. pneumoniae Neisseria meningitidis Listeria monocytogenes Pseudomonas aeruginosa non-typhoid Salmonella

Gastroenteritis: Transmission Most Common: custard pastries, potato salad

Vomiting more than diarrhea after 1-8 hours

Diarrhea watery

Organism S. aureus

Azhar Gangat (ASUMS)

28

2nd Most Common: reheated fried rice/ Chinese restaurant Most Common Nosocomial

after 1-6 hours

watery after 18 hours

B. cereus

Clostridium difficile

Unpasteurized, contaminated dairy products, undercooked meats Most Common Inflammatory: cattle, sheep, dogs or improperly cooked chicken, raw eggs, poultry products, meat, milk 2nd Most Common Inflammatory: from humans or raw chicken, egg

little

bloody/ nonbloody watery

bloody

Campylobacter jejuni

bloody after 6-8 hours

Salmonella

non-bloody

Legionella pneumophila

watery

E. coli (Enterotoxigenic)

watery

E. coli (Enteropathogenic)

watery/ bloody

E. coli (Enteroinvasive)

bloody

E. coli (Enterohemorrhagi c)

persistent

E. coli (Enteroaggressive) Shigella

A/C, water cooler contamination with atypical pneumonia Traveler’s Diarrhea: poor sanitization of water, contaminated fruits & vegetables 2nd Most Common cause of Infantile diarrhea after rotavirus

Undercooked hamburgers/ fallen apples (juice)

vomiting Most Severe Form with fever & tenesmus (dysentery)

first watery, then bloody

Listeria monocytogenes