Microbiology with diseases by taxonomy
GRAM POSITVE BACTERIA
STAIN PURPLE WHEN GRAM STAINED
FALL INTO PHYLUM FIRMICUTES
TWO MAJOR GROUPS: LOW G+C GRAM POSITIVE AND HIGH G+C GRAM POSITIVE
STAPHYLOCOCCUS (GENUS)
ARE LIVING AND REPRODUCING ON ALMOST EVERY SQUARE INCH OF YOUR SKIN.
CAN BE OPPORTUNISTIC PATHOGENS
NORMAL MEMBERS OF HUMANS MICROBIOTA
S. AUREUS AND S. EPIDERMIDIS
STAPHYLOCOCCUS
GRAM POSITIVE
FACULTATIVE ANAEROBES; PROKARYOTIC
SPHERICAL CELLS ARE CLUSTERED IN GRAPELIKE ARRANGEMENTS
CAPABLE IN GROWING IN MEDIA THAT ARE 10% NACL (SALT)
SYNTHESIZES CATALASE
S. AUREUS
S. EPIDERMIDIS
S. AUREUS: MORE VIRULENT, PRODUCES A VARIETY OF DISEASE CONDITIONS AND SYMPTOMS DEPENDING ON SITE OF INFECTION.
S. EPIDERMIDIS: NORMAL MICROBIOTA ON HUMAN SKIN. OPPORTUNISTIC PATHOGEN IN IMMUNOCOMPROMISED PATIENTS, OR WHEN INTRODUCED BY CATHETERS OR PROSTHETIC DEVICES.
STAPHYLOCOCCUS
PATHOGENICITY
CAUSED WHEN STAPHYLOCOCCI BREACH BODY'S PHYSICAL BARRIERS (SKIN OR MUCUS MEMBRANES)
RESULTS FROM THREE FEATURES:
-STRUCTURES THAT ENABLE IT TO EVADE PHAGOCYTOSIS
-PRODUCTION OF ENZYMES
-PRODUCTION OF TOXINS
STRUCTURAL DEFENSES
(STAPHYLOCOCCUS)
PROTEIN A
THE CELLS OF S. AUREUS ARE UNIFORMLY COATED WITH PROTEIN = PROTEIN A
-INTERFERES WITH ANTIBODY IMMUNE RESPONSES BY BINDING TO CLASS G (IGG) ANTIBODIES.
ANTIBODIES--> OPSONINS INHIBIT OPSONIZATION
INHIBITS COMPLEMENT CASCADE
STRUCTURAL DEFENSES
STAPHYLOCOCCUS
BOUND COAGULASE
ENZYME THAT CONVERTS FIBRINOGEN INTO LONG INSOLUBLE FIBRIN MOLECULES.
HIDES BACTERIA IN CLOTS FROM PHAGOCYTES
S. AUREUS AND S. EPIDERMIDIS: EVADE BODY DEFENSES BY SYNTHESIZING LOOSELY ORGANIZED POLYSACCHARIDE SLIME LAYERS OR CAPSULES
INHIBITS CHEMOTAXIS OF AND ENDOCYTOSIS BY LEUKOCYTES
NEUTROPHILS
FACILITATES ATTACHMENT TO ARTIFICIAL SURFACES (E.G. CATHETERS, SHUNTS, ARTIFICIAL HEART VALVES)
ENZYMES
STAPHYLOCOCCUS
(CELL FREE COAGULASE; HYALURONIDASE)
C.F. COAGULASE: TRIGGERS BLOOD CLOTTING; COMBINES WITH BLOOD PROTEIN BEFORE BECOING ENZYMATIC AND CONVERTING FIBRINOGEN TO FIBRIN THREADS
ONLY S. AUREUS SYNTHESIZES COAGULASE
H.: BREAKS DOWN HYALURONIC ACID; WHICH IS MAJOR COMPONENT OF MATRIX BETWEEN CELLS. FOUND IN 90% OF S. AUREUS STRAINS, ENABLES BACTERIA TO SPREAD BETWEEN CELLS THROUGHOUT THE BODY.
ENZYMES
S. AUREUS
STAPHYLOKINASE, LIPASES (S. AUREUS, S. EPIDERMIDIS)
STAPHYLOKINASE: DISSOLVES BLOOD CLOTS IN FIBRIN THREADS IN BLOOD CLOTSALLLOWING S. AUREUS TO FREE ITSELF FROM CLOTS. CAN ESCAPE IMMUNE SYSTEM BY ENCLOSING ITSELF IN FIBRIN CLOT (COAGULASE) CAN DIGEST ITSELF OUT OF CLOT WITH STAPHYLOKINASE AND SPREAD TO NEW LOCATIONS.
LIPASES: DIGEST LIPIDS, ALLOWING STAPHYLOCOCCI TO GROW ON THE SURFACE OF THE SKIN AND CUTANEOUS OIL GLANDS. ALL STAPH PRODUCE LIPASES.
ENZYMES
S. AUREUS
BETA-LACTAMASE
AKA PENICILLINASE: NOW PRESENT ON 90% OF S. AUREAUS STRAINS; BREAKS DOWN PENICILLIN. ALLOWS BACTERIA TO SURVIVE TREAMENT WITH BETA-LACTAM ANTIMICROBIAL DRUGS SUCH AS PENICILLIN AND CEPHALOSPORIN
TOXINS
CYTOLYTIC TOXINS
ALPHA, BETA, GAMMA AND DELTA TOXINS
ARE PROTEINS CODED BY CHROMOSOMAL GENES THAT DISRUPT CYTOLASMIC MEMBRANES OF A VARIETY OF CELLS, INCLUDING LEUKOCYTES (WBCS)
LEUKOCIDIN- A 5TH CYTOLYTIC TOXIN; LYSES LEUKOCYTES
PROVIDES STAPHYLOCOCCUS PROTECTION AGAINST PHAGOCYTOSIS
TOXINS
EXFOLIATIVE TOXINS
EACH OF TWO DISITNCT PROTEINS CAUSES THE DISSOLUTION OF EPIDERMAL DESMOSOMES CAUSING PATIENTS SKINS CELLS TO SEPARATE FROM EACH OTHERAND SLOUGH OFF OF BODY.
TOXIC SHOCK SYNDROME (TSS) TOXIN
THIS PROTEIN CAUSES TSS WHEN STAPHYLOCOCCUS PRODUCING TSS TOXIN GROW IN A WOUND OR ABRAIDED VAGINA, TOXIN CAN BE ABSORBED IN THE BLOOD AND CAUSE TSS, NON-STREPTOCOCCAL TSS.
S. AUREUS GROWS WELL IN SUPER ABSORBENT TAMPONS THAT STAY IN PLACE FOR LONG PERIODS OF TIME.
ENTEROTOXINS
5 PROTEINS DESIGNATED (A THROUGH E) STIMULATE THE INTESTINAL MUSCLE CONTRACTIONS; NAUSEA AND INTENSE VOMITING ASSOCIATED WITH STAPHYLOCOCCAL FOOD POISONING
ARE HEAT STABLE; REMAINING ACTIVE AT 100 C FOR UP TO 30 MINUTES
EPIDEMIOLOGY
S. AUREUS, S. EPIDERMIDIS
S.E: IS UBIQUITOUS ON HUMAN SKIN
S.A.: FOUND ONLY ON MOIST SKIN FOLDS
BOTH GROW IN UPPER RESPIRATORY, GASTROINTESTINAL AND UROGENITAL TRACTS
BOTH CONTRACTED BY FOMITES AND DIRECT CONTACT
PROPER HAND WASHING AND ASEPTIC TECHNIQUES ARE ESSENTIAL TO PREVENTION N HEALTHCARE SETTINGS
NONINVASIVE DISEASE
S. AUREUS: ONE OF MORE COMMON CAUSES OF FOOD POISONING; FOOD INTOXICATION; ENTEROTOXIN CONTAMINATED FOOD
COMMONLY AFFECTED FOOD: PROCESSED MEATS, CUSTARD PASTRIES, POTATO SALAD, AND ICE CREAM
WARMING OR REHEATING DOESN'T INACTIVATE ENTEROTOXIN, WHICH ARE HEAT STABLE ; HEATING DOES KILL THE BACTERIA
COURSE OF DISEASE IS 24 HRS OR LESS
CUTANEOUS DISEASES
STAPHYLOCOCCAL SCALDED SKIN SYNDROME
IMPETIGO
S. AUREUS CAUSES LOCALIZED PYOGENIC LESIONS
S.S.SKIN SYNDROME: REDDENING OF SKIN,
BEGINS AT THE MOUTH SPREADS OVER ENTIRE BODY; FOLLOWED BY LARGE BLISTERS (BLISTERS HAVE NO BACTERIA OR WBC)
IMPETIGO: SMALL, FLATTENED, RED PATCHES ON FACE, AND LIMBS PARTICULARLY ON CHILDREN WHOSE IMMUNE SYSTEMS ARENT DEVELOPED.
CUTANEOUS DISEASES
FOLLICULITIS
STY
FURUNCLE/ CARBUNCLE
FOL.: INFECTION OF THE HAIR FOLLICLE, BASE OF FOLLICLE BECOMES SWOLLEN AND PUS FILLED.
AT BASE OF EYELID ITS CALLED A STY
FUR.: BOIL, IS LARGE PAINFUL NODULAR EXTENSION OF FOLLICULITIS INTO SURROUNDING TISSUE.
CARB.: WHENN SEVERAL FURUNCLES COALESCE. EXTENDS DEEPER INTO TISSUES, TRIGGERING FEVER AND CHILLS; CHARACTERISTIC OF INNATE IMMUNITY
BACTEREMIA
S. AUREUS COMMON CAUSE OF BACTERIA IN THE BLOOD.
FURUNCLES, VAGINAL INFECTIONS, AND CONTAMINATED MEDICAL DEVICES HAVE ALL BEEN IMPLICATED IN CASES.
NOSOCOMIAL INFECTIONS ACCOUNT FOR HALF OF ALL CASES.
ENDOCARDITIS
S. AUREUS MAY ATTACK THE LINING OF THE HEART INCLUDING THE VALVES.
PATIENTS HAVE NON SPECIFIC FLU LIKE SYMPTOMS BUT QUICKLY DETERIORATE; AMOUNT OF BLOOD PUMPED FROM HEART DROPS.
50% DO NOT SURVIVE
PNEUMONIA AND EMPYEMA
STAPHYLOCOCCUS IN THE BLOOD CAN INVADE THE LUNGS; CAUSING PNEUMONIA INFLAMMATION OF LUNGS WHEN AVEOLI AND BRONCHIOLES BECOME FILLED WITH FLUID.
IN 10% OF PATIENTS WITH STAPHYLOCOCCAL PNEUMONIA (FLUID IS PUS) CONDITION KNOWN AS EMPYEMA.
OSTEOMYELITIS
WHEN STAPHYLOCOCCUS INVADES A BONE VIA TRAUMATIC WOUND OR VIA BLOOD DURING BACTEREMIA.
INFLAMMATION OF BONE MARROW AND SURROUNDING BONE. CHARACTERIZED BY PAIN IN BONE AND HIGH FEVER.
IN CHILDREN OCCURES IN GROWING LONG BONES. ADULTS IN VERTEBRAE.
DIAGNOSIS OF STAPHYLOCOCCUS
IF STAPHYLOCOCCI ISOLATED FROM AN INFECTION ARE ABLE TO CLOT BLOOD, THEN THEY ARE COAGULASE POSITIVE S. AUREUS.
GRAPELIKE ARRANGEMENTS
COAGULASE NEGATIVE STAPHYLOCOCCI ARE USUALLY S. EPIDERMIDIS
90% OF STAPHYLOCOCCI WERE SUSCEPTIBLE TO PENICILLIN IN 1945; ONLY 5% TODAY
MRSA/ VRSA
METHICILLIN RESISTANT STAPHYLOCOCCUS AUREUS
MORE POEPLE DIE OF MRSA THAN HIV IN U.S.
MRSA IS RESISTANT TO: PENICILLIN, MACROLIDES, AMINOGLYCOSIDES, AND CEPHALOSPORIN
VANCOMYSIN IS USED TO TREAT MRSA CURRENTLY
THERE IS NOW SOME VANCOMYSIN RESISTANT STAPHYLOCOCCUS AUREUS - VRSA
STAPH PREVENTION
PROPER CLEANSING OF WOUNDS AND SURGICAL OPENINGS
ASEPTIC USE OF CATHETERS AND INDWELLING NEEDLES
APPROPRIATE USE OF ANTISEPTICS
HANDWASHING
STREPTOCOCCUS
GRAM POSITIVE; ARRANGED IN PAIRS (DIPLO) OR CHAINS
COCCUS; COCCI (SPHERICAL SHAPED)
CATALASE NEGATIVE
SYNTHESIZES PEROXIDASE; FACULTATIVELY ANAEROBIC
DIFFERENTIATE SPECIES USING SEROLOGICAL CLASSIFICATION (CREATED BY REBECCA LANCEFIELD 1895-1981)
LANCEFIELD GROUPS
SEROTYPE GROUPS (LANCEFIELD GROUPS)
A TO H, AND K TO V
A, AND B MORE SIGNIFICANT STREPTOCOCCAL PATHOGENS IN HUMANS
TWO OTHERS LACK LANCEFIELD ANTIGENS
GROUP A STREPTOCOCCUS
S. PYOGENES- FORMS WHITE COLONIES 1-2MM IN DIAMETER SURROUNDED BY LARGE ZONE OF BETA-HEMOLYSIS AFTER 24 HRS ON BLOOD AGAR
PATHOGENIC STRAINS FORM CAPSULES
GROUP A STREPTOCOCCUS
PATHOGENICITY (M PROTEIN, HYALURONICACID CAPSULE )
M.P.: MEMBRANE PROTEIN DESTABILIZES COMPLEMENT. INTERFERES WITH OPSONIZATION AND LYSIS.
H.A.C.: H.A. FOUND IN BODY; WBC MAY IGNORE CAMOUFLAGED BACTERIA WITH THIS TYPE OF CAPSULE.
GROUP A STREPTOCOCCUS
PATHOGENICITY
2 STREPTOKINASES - BREAKS DOWN CLOTS
4 DEOXYRIBONUCLEASES - DEPOLYMERIZES DNA
C5a PEPTIDASE - BREAKS DOWN COMPLEMENT OF C5a PROTEIN
S. PYOGENES DECREASES MOVEMENT OF WBCS TO INFECTION SITE
GROUP A SREPTOCOCCUS
PATHOGENICITY
TOXINS
SECRETES 3 DISTINCT TOXINS - PYROGENIC TOXINS
-STIMULATE MACROPHAGES AND HELPER T LYMPHOCYTES TO RELEASE CYTOKINES
- STIMULATE FEVER, RASH, SHOCK
-AKA ERYTHROGENIC TOXINS
TOXINS CARRIED ON TEMPERATE BACTERIOPHAGES- ONLY LYSOGENIZED BACTERIA SECRETE TOXINS
GROUP A
PATHOGENICITY
S, PYOGENES PRODUCES TWO TYPES OF MEMEBRANE BOUND PROTEINS CALLED STREPTOLYSINS
LYSE RBCS, WBCS, AND PLATELETS
INTERFERE WITH OXYGEN CAPACITY OF BLOOD, IMMUNITY AND BLOOD CLOTTING
GROUP A
EPIDEMIOLOGY
FREQUENTLY INFECTS PHARNYX OR THE SKIN
CAUSES DISEASE ONLY WHEN NORMAL COMPETEING MICROBIOTA ARE DEPLETED
CAN AFFECT DEEP TISSUE WITH BREAK IN BARRIERS OF SKIN
IS SPREAD BY RESPIRATORY DROPLETS
GROUP A
STREPTOCOCCAL DISEASES
PHARYNGITIS, SCARLET FEVER
P: SORE THROAT CAUSED BY STREPTOCOCCI, COMMONLY KNOWN AS STREP THROAT, IS A KIND OF PHARYNGITIS; ITS INFLAMMATION OF THE PHARNYX, ACCOMPANIED BY FEVER, MALAISE AND HEADACHE. BACK OF PHARNYX RED WITH SWOLLEN LYMPH NODES AND PURULET ABSCESSES COVERING TONSILS.
S.F.: "SCARLETINA" OFTEN ACCOMPANIES STREPTOCOCCAL PHARYNGITIS WHEN THE INFECTION INVOLVES A LYSOGENIZED STRAIN OF s. PYOGENES. RASH ON BODY AND STRAWBERRY COLORED TONGUE. RASH DISAPPEARS IN A WEEK AND FOLLOWED BY SLOUGHING SKIN.
GROUP A
STREPTOCOCCAL DISEASES
PYODERMA AND ERYSIPELAS
STREPTOCOCCAL TSS
P AND E: PYODERMA IS A CONFINED PUS PRODUCING LESION THAT USUALLY OCCURS ONTHE EXPOSED SKIN OF THE FACE ARMS OR LEGS. CAN BE CONTRACTED BY DIRECT CONTACT WITH INFECTED PERSON OR FOMITES. AKA IMPETIGO (STREP. VERSION)
WHEN STREPTOCOCCAL INFECTION INVOLVES SURROUNDING LYMPH NODES AND TRIGGER PAIN AND INFLAMMATION ITS CALLED A ERYSIPELAS. MOST COMMON ON CHILDRENS FACES.
S.TSS: CAN SPREAD AND LEAD TO BACTEREMIA AND SEVERE MULTI SYSTEM INFECTIONS PRODUCING STSS. CAUSES INFLAMMATION AT SITE OF INFECTION, PAIN, FEVER, CHILLS, MALAISE NAUSEA VOMITING, AND DIARRHEA. FOLLOWED BY INCREASED PAIN, ORGAN FAILURE, SHOCK. 40% PATIENTS DIE.
GROUP A STREPTOCOCCAL DISEASES
NECROTIZING FASCIITIS
RHEUMATIC FEVER
N.F: "FLESH EATING BACTERIA", STREPTOCOCCI ENTER THE BODY THROUGH BREAKS OF SKIN, SECRETE TOXINS AND ENZYMES THAT DESTROY TISSUE, AND EVENTUALLY MUSCLE AND FAT TISSUE ARE DESTROYED. SPREAD DEEP IN TISSUE ALONG THE FASCIA. ALSO INVOLVES TOXEMIA (TOXINS IN BLOOD). FAILURE OF MAN ORGAMS. 50% PATIENTS DIE.
R.F: COMPLICATION OF UNTREATED S. PYOGENES PHARYNGITIS. INFLAMMATION LEADS TO DAMAGE OF HEART VALVES AND MUSCLE. ITS AN AUTOIMMUNE RESPONSE; SREPTOCOCCAL ANTIGENS CROSS REACT WITH HEART ANTIGENS. MORE PREVELANT BEFORE ANTIMICROBIAL DRUGS.
GROUP A STREPTOCCCAL DISEASES
GLOMERULONEPHRITIS
G.: STREPTOCOCCUS GROUP A ARE NOT REMOVED FROM CIRCULATION BUT INSTEAD ACCUMULATE IN THE GLOMERULI (SM. BLOOD VESSELS) OF THE KIDNEYS NEPHRONS (FILTERING UNITS). RESULT IS GLOMERULONEPHRITIS. INFLAMMATION OF THE GLOMERULI AND THE NEPHRONS LEADING TO HYPERTENSION. AND LOW URINE OUTPUT.
GROUP B STREPTOCOCCUS
S, AGALACTIAE
GRAM POSITIVE COCCUS, .6-1.2 UM D.
DIVIDESTO FORM CHAINS, BETA HEMOLYTIC.
HAS:
GROUP SPECIFIC POLYSACCHARIDE CELL WALL ANTIGENS, FORMS BUTTERY COLONIES 2-3 MM IN D, SMALL ZONE OF BETA HEMOLYSIS AFTER 24 HRS OFGROWTH ON BLOOD AGAR, BACITRACIN RESISTANT.
GROUP B STREPTOCOCCUS
PATHOGENICITY
S. AGALACTIAE DO FORM CAPSULES, ANTIBODIES TARGET ITS CAPSULAR ANTIGENS, SO CAPSULES ARE NOT PROTECTIVE. HAS A PREDI;ECTION FOR NEWBORNS WHOVE NOT YET FORMED TYPE SPECIFIC ANTBODIES.
PRODUCE ENZYMES- PROTEASES (CATABOLZE PROTEINS) , HEMOLYSINS (LYSE RED BLOOD CELLS) DEOXYRIBONUCLEASE , HYALURONIDASE
GROUP B STREPTOCOCCUS
EPIDEMIOLOGY
NORMALLY COLONIZED THE GASTROINTESTINAL, GENITAL AND URINARY TRACTS. DISEASES IN ADULTS USUALLY FOLLOW WOUND INFECTIONS AND CHILDBIRTH. STARTING TO BE SIGNIFICANT PATHOGEN IN ELDERLY.
60% OF NEW BORNS INOCULATED WITH STRAIN BY PASSAGE THROUGH BIRTH CANAL OR MEDICAL PERSONNEL. DONT CAUSE DISEASE IF MATERNAL ANTI BODIES HAVE PASSED THORUGH PLACENTA. UNINFECTED MOTHERS INCREASE MORTALITY RATES BY 50%
GROUP B STREPTOCOCCUS DISEASES
S. AGALACTIAE CAUSE OF PEURPERAL FEVER/ CHILD BIRTH FEVER
ALSO ASSOCIATED WITH:
NEONATAL BACTEREMIA, MENINGITIS, AND PNEUMONIA.
25% INFANTS SURVIVING GROUP B STREPTOCOCCAL MENINGITIS HAVE PERMANANENT NEUROLOGICAL DAMAGE, INCLUDING BLINDNESS, DEAFNESS, OR SEVERE MR.
ELDERLY ALSO AT RISK 25% DIE FROM STREPTOCOCCAL DISEASES.
OTHER BETA HEMOLYTIC STREPTOCOCCI
S. EQUISIMILIS WHICH CAUSES PHARYNGITIS
S. ANGINOSUS PRODUCES PUS CONTAINIG ABSCESSES.
PENICILLIN EFFECTTIVE FOR BOTH
BOTH ARE ONLY TWO OTHER BETA HEMOLYTIC PATHOGENS
ALPHA HEMOLYTIC: THE VIRIDANS GROUP
PRODUCE A GREEN PIGMENT WHEN GROWN ON BLOOD MEDIA
LACK GROUP SPECIFIC CARBOHYDRATES
SUSCEPTICIBLE TO PENICILLIN
SEPARATE GENUS: ABIOTROPHIA (BY SOME)
OTHER NAMES: S. MITIS, S. SANGUIS
INHABIT: MOUTH, PHARYNX, GI TRACT, GENITAL TRACT AND URINARY TRACT OF HUMANS
ALPHA HEMOLYTIC: THE VIRIDANS GROUP
ARE OPPORTUNISTS THAT PRODUCE PUS FILLED ABDOMINAL LESIONS
ARE ONE CAUSE OF DENTA CARIES STIC K TO DENTAL SURFACES VIA DEXTRAN INSOLUBLE POLYSACCHARIDE
COLONIZE WITH OTHER BACTERIA FORMING BIOFILMS ON TEETH ENAMEL KNOWN AS DENTAL PLAQUE
IF THEY GET IN BLOOD CAN CAUSE MENINGITIS, AND ENDOCARDITIS
STREPTOCOCCUS PNEUMONIAE
DISCOVERED BY LOUIS PASTEUR IN 1881 IN PNEUMONIA PATIENTS
GRAM POSOTOVE COCCUS; 0.5- 1.2 UM IN D
FORMS SHORT CHAINS OR MORE COMON PAIRS (DIPLOCOCCUS ONCE CLASSIFIED GENUS)
92 DIFFERENT STRAINS ARE KNOWN TO INFECT HUMANS
STREPTOCOCCUS PNEUMONIAE
PATHOGENICITY
NORMAL MEMEBER OF PHARYNGEAL MICROBIOTA THAT CAN COLONIZE LUNGS, SINUSES AND MIDDLE EAR
CELSS OF VIRULENT STRAINS SURROUNDED BY POLYSACCHARIDE CAPSULE; PROTECTS FROM DIGESTION OF ENDOCYTOSIS.
CAPSULE REQUIRED FOR VIRULENCE
CELL WALL CHEMICAL PHOSPHORYLCHOLINE; HIDE IN BODY CELLS
CAN PASS INTO THE BLOOD AND THE BRAIN
SECRETE PROTEIN ADHESIN
STREPTOCOCCUS PNEUMONIAE
PATHOGENICITY
SECRETES 1GA PROTEASE, AND PNEUMOLYSIN
PRODUCES TRANSMEMBRANE PORES; RESULTS IN LYSIS OF CELLS
PNEUMOLYSIN SUPPRESSES THE DIGESTION OF ENDOCYTIZED BACTERIA
INTERFERES WITH LYSOSOMMES ACTION
STREPTOCOCCUS PNEUMONIAE
EPIDEMIOLOGY
GROWS IN MOUTHS AND PHARYNGES OF 75% OF HUMANS WITHOUT CAUSING DISEASE
WHEN TRAVELED TO LUNGS; CAUSES DISEASE
MOST COMMON IN CHILDRENA ND EDERLY
PNEUMOCOCCAL DISEASES
PNEUMOCOCCAL PNEUMONIA CONSTITUTES 85% OF ALL CASES OF PNEUMONIA
SINUSITIS AND OTISIS MEDIA
BACTEREMIA AND ENDOCARDITIS
PNEUMOCOCCAL MENINGITIS
ENTEROCOCCUS
TWO PATHOGENS TO HUMANS:
E. FAECALIS; E. FAECIUM
GRAM POSITIVE; CATALASE NEGATIVE COCCI
SPHERICAL AND LIVE IN INTESTINAL TRACTS OF ANIMALS
UNENCAPSULATED
TYPICALLY NON HEMOLYTIC
FORM SHORT CHAINS AND PAIRS
GROW AT TEMPS OF 45C; PH AS HIGH AS 9.6
6.5% SALT/ NACL; OR 40% BILE SALT BROTHS
ENTEROCOCCUS
PATHOGENESIS, EPIDEMIOLOGY, AND DISEASES
E. FAECALIS: UBIQUITOUS IN HUMAN COLON
BOTH HAVE ABIITY TO ADHERE TO EPITHELIAL CELLS , AND SECRETE BACTERIOCINS WHICH INHIBIT GROWTH OF OTHER BACTERIA
CAN CAUSE SERIOUS DISEASE F THEY ARE INTRODUCED TO OTHER PARTS OF THE BODY SUCH AS LUNGS, URINARY TRACT, AND BLOODSTREAM
ACCOUNT FOR 10% NOSOCOMIAL INFECTIONS; AND CAUSE BACTEREMIA, ENDOCARDITIS AND WOUND INFECTIONS..
BACILLUS
GRAM POSITIVE BACILLUS DIVIDED INTO ENDOSPORE FORMING AND NON ENDOSPORE FORMING GENERA
ENDOSORE FORMING ARE: BACILLUS AND CLOSTRIDIUM
BACILLUS ANTHRACIS
ROD SHAPED; FACULTATIVELY ANAEROBIC
ENDOSPORE FORMING; NORMALLY DWELL IN SOIL
SINGLY, PAIRED OR IN CHAINS
CAN SURVIVE FOR CENTURIES HAS ANTHRAX TOXINS
BACILLUS ANTHRACIS
EPIDEMIOLOGY
PRIMARILY A DISEASE OF HERBIVORES; HUMANS CONTRACT FROM INFECTED ANIMALS
CAN IN VADE IN ONE OF THREE ROUTES: INHALATION OF ENDOSPORES, INGESTION OF ENDOSPORES, AND INOCULATION OF ENDOSPORES THROUGH BREAK INT HE SKIN
BACILLUS ANTHRACIS
DISEASE
CAUSES ONLY ONE DISEASE - ANTHRAX
CAN HAVE THREE CLINICAL MANIFESTATIONS;
GASTROINTESTINAL ANTHRAX, INTESTINAL HEMORRHAGING, DEATH
CUTANEOUS ANTHRAX - CREATES ESCHARS- RELEASES ANTHRAX TOXIN IN THE BLOOD AND PRODUCES TOXEMIA
INHALATION ANTHRAX. SECRETE TOXINS IN LUNGS THAT ARE ABSORBED IN THE BLOOD STREAM. PRODUCING TOXEMIA. IF CAUGHT LATE MORTALITIY RATE IN NEAR 100%
CLOSTRIDIUM
ANAEROBIC; GRAM POSITIVE ENDOSPORE FORMING BACILLUS
IN SOIL, WATER, SEWAGE, GI TRACT OF ANIMALS AND HUMANS
PATHOGENICITY S DUE TO ENDOSPORE BEING ABLE TO SURVIVE HARSH CONDITIONS
SECRETES HYSTOLYTIC TOXINS, ENTEROTOXINS AND NEUROTOXINS
MOST COMMON: C. PERFRINGENS, C. DIFFICILE, C. BOTULINUM, AND C. TETANI
CLOSTRIDIUM PERFRINGENS
PATHOGENESIS, EPIDEMIOLOGY, AND DISEASE
LARGE ALMOST RECTANGULAR GRAM POSITIVE BACILLUS
C. PERFRINGENS TYPE A IS MOST VIRULENT SEROTYPE
PRODUCES 11 TOXINS THAT LYSE ENTHROCYTES, AND LEUKOCYTES; INCREASE VASCULAR PERMEABILITY, REDUCE BLOOD PRESSURE AND KILL CELLS RESULTING IN IRREVERSIBLE DAMAGE.
SEVERITY RANGES FROM MILD FOOD POISONING TO LIFE TREATENING ILLNESS
CLOSTRIDIUM PERFRINGENS
PATHOGENESIS, EPIDEMIOLOGY, AND DISEASE
FOOD POISONING IS BENIGN RESUTS ARE ABDOMINAL CRAMPA, WATERY DIARRHEA, NO FEVER OR NAUSEA OR VOMITING
IT IS NOT INVASISVE BUT WHEN INTRODUCED BY SOME TRAUMATIC EVENT ( GUN SHOT, PUNCTURE ETC) CAB GERMINATE IN DEEP TISSUE
CLOSTRIDIAL TOXINS INDUCE SWELLING AND TISSUE DEATH
RAPIDLY REPRODUCING BACTERIA CAN SPREAD INTO SURROUNDING TISSUE ACCOMPANIED BY PRODUCTION OF FOUL SMELLING, GASEOUS, BACTERIAL WASTE PRODUCTS -- GAS GANGRENE
SHOCK, KIDNEY FAILURE AND DEATH CAN FOLLOW WITHIN A WEEK OF INFECTION
GAS GANGRENE TREATMENT
C. PERFRINGENS
DEAD TISSUE AFFECTED BY GAS GANGRENE HAS TO QUICKLY BE SURGICALLY REMOVED AND BY LARGE DOSES OF ANTITOXIN AND PENICILLIN.
OXYGEN APPLIED UNDER PRESSURE MAY ALSO BE HELPFUL
MORTALITY RATE WITH TREATMENT EXCEEDS 40%
REFRGERATION PREVENTS TOXIN FORMATION AND REHEATING DESTROYS TOXIN THAT HAS FORMED
AS WELL AS PROPER CLEANING OF WOUNDS
CLOSTRIDIUM DIFFICILE
MOTILE, ANAEROBIC INTESTINAL BACTERUIM
ABOUT 1.5 UM IN WIDTH; 3-6.5 UM IN LENGTH
FORMS OVAL SUBTERMINAL ENDOSPORES
PRODUCES TWO TOXINS A & B; ENZYME HYALURONIDASE
CLOSTRIDIUM DIFFICILE
PATHOGENESIS, EPIDEMIOLOGY, AND DISEASE
IT IS AN OPPORTUNISTIC PATHOGEN AND IS A RESIDENT IN MICROBIOTA OF INTESTINE
NORMAL PROPORTIONS OF DIFFERENT BACTERIA IN COLON ARE SIGNIFICANTLY ALTERED
HARDY ENDOSPORES GERMINATE ENABLING IT TO BECOME PREDOMINATE INTESTINAL BACTERIUM
TOXINS AND ENZYMES IT PRODUCES HEMORRHAGIC DEATH OF INTESTINAL WALL
CAN PRODUCE LIFE THREATENING PSEUDOMEMBRANOUS COLITIS- LARGE SECTIONS OF COLON SLOUGH OFF
MAJOR CAUSE OF ELDERLY DEATH
CLOSTRIDIUM BOTULINUM
ANAEROBIC, ENDOSPORE FORMING, GRAM POSITIVE BACILLUS
COMMON IN SOIL AND WATER WORLD WIDE
ENDOSPORES CAN SURVIVE IMPROPER CANNING OF FOOD CAN PRODUCE POWERFUL NEUROTOXIN THAT CAUSES BOTULISM
CLOSTRIDIUM BOTULINUM
PATHOGENESIS
PRODUCE ON OF SEVEN ANTIGENICALLY DISTINCT BOTULISM TOXINS (A THROUGH G)
CONSIDERED ONE OF DEADLIEST TOXINS KNOWN- 30 GRAMS WOULD BE ENOUGH TO KILL EVERY PERSON IN THE U.S.
EACH OF SEVEN TOXINS IS A QUATERNARY PROTEIN
BOTULISM TOXINS ACT BY BINDING IRREVERSIBLY TO NEURONAL CYTOPLASMIC MEMEBRANES, PREVENTING FUSION OF VESICLES AND SECRETION OF ACETYLCHOLINE INTO THE SYNAPTIC CLEFT.
PREVENTS MUSCLE CONTRACTION RESULTING IN FLACCID PARALYSIS
CLOSTRIDIUM BOTULINUM
EPIDEMIOLOGY AND DISEASES
BOTULISM IS NOT AN INFECTION ITS AN INTOXICATION CAUSED BY BOTULISM TOXIN.
THREE MANIFESTATIONS: FOODBORNE BOTULISM, INFANT BOTULISM, AND WOUND BOTULISM
CLOSTRIDIUM BOTULINUM
TREATMENT
THREE APPROACHES:
REPEATED WASHING OF THE INTESTINAL TRACTTO REMOVE CLOSTRIDIUM
ADMINISTRATION OF ANTIBODIES AGAINST BOTULISM TOXIN TO NEUTRALIZE TOXIN IN THE BLOOD BEFORE IT CAN BIND TO NEURONS
ADMINISTRATION OF ANTIMICROBIAL DRUGS TO KILL CLOSTRIDIA IN INFANT AND WOUND BOTULISM CASES
CLOSTRIDIUM TETANI
SMALL MOTILE OBLIGATE ANAEROBE, THAT PRODUCES A TERMINAL ENDOSPORE, GIVING CELL A DISTINCTIVE LOLLIPOP APPEARANCE
IN SOIL, DUST AND GI TRACT OF ANIMALS AND HUMANS
EXTREMELY SENSITIVE TO OXYGEN
TOXIN CAUSES DISEASE TETANUS
CLOSTRIDIUM TETANI
PATHOGENESIS
TETANOSPASMIN (TETANUS TOXIN) POTENT NEUROTOXIN RELEASED WHEN C. TETANI CELLS DIE. ITS COMPOSED OF TWO POLYPEPTIDES HELD TOGETHER BY A DISULFIDE BOND.
BLOCKS THE RELEASE OF INHIBITORY NEUROTRANSMITTER .
WITH BLOCKAGE EXCITATORY ACTIVITY IS UNREGULATED, MUSCLES SIGNALED TO CONTRACT SIMULTANEOUSLY
MUSCLES ON BOTH SIDES OF JOINT DONT RELAX
CONTRACTION CAN BE SO SEVERE THEY BREAK BONES
CLOSTRIDIUM TETANI
EPPIDEMIOLOGY, DISEASE
INCUBATION PERIOD IS A FEW DAYS TO A WEEK
INITIAL SIGN IS TIGHTENING OF NECK AND JAW MUSCLES - LOCKJAW
OTHER SYMPTOMS: SWEATING, DROOLING, GROUCHINESS, AND CONSTANT BACK SPASMS, CAN SPREAD AND CAUSE HEART BEAT IRREGULARITIES, FLUCTUATIONS IN BLOOD PRESSURE, EXTENSVE SWEATING
UNRELENTING CONTRACTION OF DIAPHRAGM RESULT IN FINAL INHALATION; CANT EXHALE; DEATH
MORTALITY RATE 50%; NEONATAL TETANUS IS 90% UMBILICAL STUMP
LISTERIA MONOCYTOGENES
LLOW G+C, GRAM POSITIVE NON EDOSPORE FORMING BACILLUS
FOUND IN SOIL, WATER, MAMMALS, BIRDS FISH, AND INSECTS
ENTERS THE BODY IN CONTAMINATED FOOD AND DRINK
LISTERIA MONOCYTOGENES
PATHOGENESIS, EPIDEMIOLOGY, DISEASE
BINDS TO SURFACE OF MACROPHAGE OR A CELL OF THE LIVER OR GALL BLADDER.
TRIGGERS ITS OWN ENDOCYTOSIS TO BECOME A FACULTATIVE INTRACELLULAR PARASITE
SYNTHESIZES PORE FORMING PROTEIN- LISTERIOLYSIN O (PUNCTURES PHAGOSOME MEMBRANE)
RELEASING BACTERIUM INTO HOST CELLS CYTOSOLE; BEFORE LYSOSOME CAN FUSE PHAGOSOME.
CAN TRANSFER ITSELF WITHOUT HAVING TO LEAVE HOST CELL
FORMS A PSEUDOPOD
VIRULENCE DIRECTLY RELATED TO ABILTY T LIVE IN CELLS
LISTERIA MONOCYTOGENES
PATHOGENESIS, EPIDEMIOLOGY, DISEASE
PRODUCES NO TOXINS OR ENZYMES THAT MAKE IT VIRULENT
BACTERIUM ONLY PRODUCES RAPIDLY WHEN IN A HOST (37C)
LITTLE T NO EFFECT ON HEALTHY ADULTS
SEVERE EFFECT ON: FETUSES, NEWBORNS, ELDERLY AND IMMUNOCOMPROMISED PATIENTS
IN THESE PATIENTS LISTERIA TRAVELS VIA BLOODSTREAM TO BRAIN CAUSING MENINGITIS AND POSSIBLY DEATH.
LOW TEMPS DO NOT INHIBIT BACTERIA
MYCOPLASMAS
SMALLEST FREE LIVIING MICROBES THAT CAN GROW AND REPRODUCE INDEPENDENTLY OF OTHER CELLS.
STAIN PINK, HAVE NO CELL WALLS
FACULTATIVE ANAEROBES
COLONIES HAVE FRIED EGG APPEARANCE
MYCOPLAMA PNEUMONIAE CAUSES PRIMARY ATYPICAL PNEUMONIA (WALKING PNEUMONIA)
MYCOPLASMA HOMINIS CAN CAUSE PID
MYCOPLASMA GENITALIUM CAN CAUSE NONGONOCOCCAL URETHRITIS
CORYNEBACTERIUM DIPTHERIAE
TRANSMITTED VIA RESPIARTORY DROPLETS
CONTAINS A BACRIOPHAGE THAT CODES FOR DIPHTHERIA TOXIN, WHICH CAUSES SYMPTOMS FOR POTENTIALLY FATAL DISEASE DIPHTHERIA
DIAGNOSED BY THE ELEK TEST
MYCOBACTERIUM
HIGH G+C, NON ENDOSPORE FORMING PATHOGEN
HAVE AN ABUNDANCE OF WAXY LIPID/ MYCOLIC ACID IN CELL WALL
GROWS SLOWLY GENERATION TIME VARIES FORM HOURS TO SEVERAL DAYS
PROTECTED FROM LYSIS ONCE PHAGOCYTIZED
CAPABLE OF INTRACELLULAR GROWTH
RESISTANT TO GRAMM STAINING, DETERGENTS, MANY ANTIMICROBIAL DRUGS AND DESICCATION
ACID FAST STAIN
PATHOGENIC TYPES: M. TUBERCULOSIS, M. LEPRAE;
M. AVIUM-INTRACELLULARE AND M. ULCERANS CAUSE EMERGING MYCOBATERIAL DISEASES
MYCOBACTERIUM TUBERCULOSIS
PRIMARY MYCOBACTERIAL DISEASE
GROWN ON DUL YELLOW AGAR CALLED LOWENSTEIN -JENSEN AGAR
VIRULENT STRAINS HAVE A CELL WALL COMPONENT - CORD FACTOR
PRODUCES DAUGHTER CELLS THAT REMAIN ATTACHED IN PARALLEL ALIGNMENTS
INHIBITS MIGRATION OF NEUTROPHILS; TOXIC TO MAMMAL CELLS
MYCOBACTERIUM TUBERCULOSIS
PATHOGENESIS AND DISEASE
WAXY WALL PROTECTS FROM DISSECATION
CAN REMAIN VIABLE IN DRIED AEROSOL DROPLETS FOR 8 MONTHS
NOT TO VIRULENT; ONLY 5% INFECTED DEVELOP DISEASE
KILLS 50% OF UNTREATED PATIENTS
3 TYPES: PRIMARY, SECONDARY, DISSEMINATED
PRIMARY TUBERCULOSIS
PRIMARY TB TYPICALLY OCCURS IN CHILDREN, INVOLVES FORMATION OF SMALL HARD NODULES IN LUNGS- TUBERCLES
STAGES:
1. IN HALATION OF RESPIRATORY DROPLETS; MINIMUM INFECTIOUS DOSE IS 10 CELLS, HAVE ADHESIVE PILI THAT ATTACH TO LAMININ
2. MACROPHAGES IN THE AVEOLI OF LUNGS PHAGOCYTIZE PATHOGENS BT ARE UNABLE TO DIGEST THEM. IT INAVDES CELLS LINING AVEOLI
3. REPLICATE FREELY WITHIN HOST CELLS, KILLING THEM. INFECTED CELLS RELEASE CHEMOKINES AND ATTRACT MORE MICROPHAGES, BACTERIA RELEASED FROM DEAD MACROPHAGES GET PHAGOCITIZED BY NEW MACROPHAGES BEGINNING CYCLE ANEW.
4. LIGHTLY APPRESSED MACROPHAGES SURROUND THE SIGHT OF INFECTION FORMING A TUBERCLE
5. INFECTED CELLS IN THE CENTER OF THE TUBERCLE DIE, RELEASING M. TB AND PRODUCING CASEOUS NECROSIS
TUBERCLE FILLED WITH AIR CALLED TUBERCULOUS CAVITY
GHON COMPLEXES- CALCIUM DEPOSITS AROUND THE TUBERCLES
SECONDARY TUBERCULOSIS
RESULTS WHEN M. TB BREAKS THE STALEMATE, RUPTURES THE TUBERCLE AND REESTABLISHES AN ACTIVE INFECTION IN WHICH BACTERIA SPREAD THROUGH THE LUNGS VIA THE BRONCHIOLES
DISSEMINATED TUBERCULOSIS
RESULTS WHEN SOME MACROPHAGES CARRY THE PATHOGENS VIS THE BLOOD AND LYMPH TO A VARIETY OF SITES, INCLUDING: BONE MARROW, SPLEEN. KIDNEYS, SPINAL CORD AND BRAIN
OLD NAME- CONSUMPTION
MYCOBACTERIUMTUBERCULOSIS
EPIDEMIOLOGY
PANDEMIC IN OTHER PARTS OF THE WORLD
KILLING 2 MILLION ANNUALLY
1/3 WORLD POPULATION INFECTED WITH M T.B. AND 10% DEVELOP LIFE THREATENING CASE
RISK FACTORS INCLUDE: DIABETES, POOR NUTRITION, STRESS, CROWEDED LIVING CONDITIONS, ALCOHOL AND DRUG ABUSE AND SMOKING
MYCOBACTERIUM TUBERCULOSIS
DIAGNOSIS TREATMENT AND PREPVENTION
TUBERCULIN SKIN TEST USED TO SCREEN PATIENTS FOR POSSIBLE EXPOSURE;HARD RED SWELLING AT TEST SITE 24-72 HRS LATER IS POSITIVE
DOESNT INDICATE CURRENT DISEASE
CHEST XRAYS USED TO REVEAL TUBERCLES IN LUNGS (PRIMARY IN LOWER LUNGS AND SECONDARY HIGHER IN LUNGS)
MDR-TB AND XDR-TB (MULTI DRUG RESISTANT; EXTENSIVELY DRUG RESISTANT TB)
BCG VACCINE NOT WARRANTED IN THE U.S.
MYCOBACTERIUM LEPRAE
CAUSES LEPROSY
TUBERCULOID LEPROSY IS A NON PROGRESSIVE FORM OF THE DISEASE
LEPROMATOUS LEPROSY RESULTS IN PROGRESSIVE DESTRUCTION OF BODY STRUCTURES
NARCADIA AND ACTINOMYCES
OPPORTUNISTIC PATHOGEN NARCADIA ASTEROIDES HAS ELONGATED CELLS RESEMEBLING FUNGAL HYPHAE
ITS ACID FAST BECAUSE OF PRESENCE OF MYCOLIC ACID IN CELL WALL
CUTANEOUS INFECTIONS MAY PRODUCE MYCETOMA
ACTINOMYCES - ANOTHER OPPORTUNISTIC PATHOGEN WITH ELONGATED CELLS, NOT ACID FAST; CAUSES ACTINOMYCOSIS.