Download G-rods

G- negative aerobic bacilli:
1) Facultative anaerobic fermenters . Enterobacteriaceae
- E.coli, Salmonella, Schigella, Enterobacter, Citrobacter,
Serratia, Klebsiella, Proteus, Morganella, Providencia,
Vibrionaceae: Vibrio, Aeromonas, Plesiomonas
Campylobacter, Helicobacter
2) Obligately aerobic nonfermenters: Pseudomonadaceae
– Pseudomonas sp., Stenotrofomonas maltofilia, Acinetobacter
3) Haemophilus and related genera (Actinobacillus, Pasteurella)
4) Unusual bacilli (Bordetella, Franciscella, Brucella, Legionella,
Afipia, Bartonella, Calymmatobacterium, Cardiobacterioum,
Eikenella, Flavobacterium, Streptobacillus, Spirillum)
Pseudomonas aeruginosa
Hospital enviromnemt – in food, cut flowers, toilets, mops,
respiratory equipement, desinfectant solution
Persistent carriage less than 6% in healthy, 38% in hospitalised,
78% in immunocompromised
Hospital - nosocomial infections
• Hospital infection - infection, that arises in connection to
hospitalisation or to diagnostical, therapeutic or preventive processes.
I does not necessary have to present during the hospitalisation and not
every infection arising during hospitalisation is nosocomial
• Risk factors - age,accompanying diseases, surgical processes therapy ATB, imunosupression, irradiation, not vital reservoire - indwelling
catheters)
• Microbes
• Ways of transmission - in direct (inhalation, ingescion, inoculation) ,
direct (contact of infected skin or mucous membrane with healthy)
• Prevetion - organisation of health process, construction, food supply,
health process technics, asepsis and antisepsis, nursery approches,
isolation, monitoring, surveillance, role of microbiologickal
laboratory)
• ATB therapy
Role of microbes in hospital infections
• Staphylococcus aureus - problems of per secundam healing wounds
(70 ies). Virulence, colonisation capacitiy, resistence - MRSA methicilin resistent staphylococcus aureus (80 ies)
• G-rods (60% of HI) - urinary tract infections, respiratory infections,
wound infection, GIT
• Opportunistic pathogens - Ps. aeruginosa (Hospital environmente –
food, cut flowers, water, toels, mops, respiration devices, desinfection
solutions. Persistent carriage in less than 6% helathy, 38% in
hospitalised, 78% imunocompromised) and other non fermenting Grods - Acinetobacter, Stenotrophomonas maltophilia, Burkholderia
cepacia… - present in environmentí (Legionella pneumophila climatisation)
• PK negative staphylococci - colonisation of plastic material of
indwelling catheters
• Viruses - blood borne infection agenses HIV, VHB, VHC, CMV….
ATB therapy in hospital infections
• Overuse of ATBe - resistence and multiresistence (selection pressure
of ATB and transmission in hospital environment), toxic side effects,
economic burden, deterioration of physiological microflora
• Racional indication - preventive in spread of HI
• Prophylaxis - oriented to anaerobe infectione - perioperative
preparation for GIT and UGT surgery, in instrumental examination of
patients with bacteriuria
• ATB surveys - monitoring of ATB susceptibility
• Restrictive policy - time restricted contraindication of some ATB
• Rotation of atb - periodical changes of used - decreasing of selection
pressure
• Combination of atb - agains possible resistent mutnants, broader
antimicrobial spectrum
Primarily oportunistic
Structura factors and toxins – virulence factors
Nonfermentative – cytochromoxidase – dif.dg.
Capsule production
Diffusible pigments - pyocianin, pyorubin,
VIRULENCE FACTORS
Pilli - adherence
Polysaccharide capsule – antifagocytic properties, anchor to bacteria
Endotoxin – LPS sepsis syndrome
Exotoxin A – most important, block eukaryotic cells proteosyntesis
Exoenzyme S – heat stability, inhibition of proteosynhesis
Elastane – destruction of elastase of blood vessels wall
Alkaline protease – tissu destruction
Phospholipase C – breaks down lipids and lecithin, tissue destruction,
Opportunistic, minimal nutritional requirements, temperature tolerant
4*- 42* C, resistant to ATB and disinfectants
Isolation without evidence of disease does not justify therapeutic
intervention
Clinical syndroms
Bacteraemia and endocarditis - originate in respiratory, UG tract or
wound infections, i.v. drug abusers, tricuspidal valve, chronic course
Pulmonary infections . Colonisation – necrotising bronchopneumonia,
cystic fibrosis infection, respiratory tract therapy equipement
contamination, invasive bilateral bronchopneumonia with microabscess
formation and tissue necrosis
Ear infections – external otits, swimmer´s ear – local infections
invasive malignant external otitis – life threating, chronic otitis media
Burn wound infections – colonisation, vascular damage, tissue
necrosis, bacteraemia. Moist surface of burns and neutropaenia
Urinary tract infection – indwelling catheters
Oportunistic infections - moist reservoirs, circumvention, absence of
host defenses – cutaneous trauma, elimination of normal flora by ATB,
neutropenia
Gastroenteritis, Eye infections, Musculosceletal infections
Laboratory diagnosis
Cultivation – simple nutritional requirements, aerobic incubation,
growth in broth air interface – presence of nitrate.
Identification – colonial morphology, rapid biochemical tests – COX,
presence of pigment, characteristic odor
For epidemiological investigation – nucleic acid analysis,
phagotypisation, pyocin typisation, serotyping
Cultivation
• Ps. aeruginosa on blood agar - mucous gray colonies with
methal lood and pigment and characteristic smell Production
of diffusibile pigment - pyocyanin and of capsule
Biochemical properties of
Ps.aeruginosa
• Minimal nutrition requirements, thermotolerant 4*- 42* C, rezistent
to ATB and desinection
Nonfermenting – cytochromoxidase – dif.dg. (COX test), Hajn tube
medium - without change - red - detection of pigment and smell.On
transparent media - green pigment
• Oportunistic: factors of virulence: Pilli - adherence
Polysacharid capsule – antifagocytosis, attachment, Endotoxin – LPS sepsis
Exotoxin A – most important, blocs proteosynthesis of eukaryotic cells Alkalic
protease – destruction of tissu Phospholipase C – destruction of lipids and lecithin,
destruction of tissue
Other pseudomonas –
Ps. Pseudomallei – asymptomatic, melidiosis, - localised suppurative
infection with lymphadenitis, fever, malaise, pulmonary disease
(bronchitis – necrotising pneumonia) !!highly infectious in lab.
processing
Ps. Cepacia – in immunocompromised respiratory and urinary tract
infections, cystic fibrosis
Insignificant water born contaminant
Treatment,
Frustrating – imunocompromised host defense
typical ATB resistence
induction of ATB inactivating enzymes
transfer of plasmid mediated resistance
Aminoglycosides – ineffective in the site of infection (acidic
encironment in abscess)
Combination of ATB – beta lactam+aminoglycosides, Sulfonamides,
Prevention,
Of contamination of sterile equipement and cross contamination of
patients.
Broad spectrum ATB should be avoided – suppression of normal flora
and overgrowth of resistant pseudomonas
Stenotrophomonas maltophilia
- second most common isolated G-nonfermenter
- Opportunistic nosocomial pathogen
- Resistant to AMG and betalactams, IMI, fluoroquinolons
(long term ATB therapy is predisposing to the infection with it)
- CMP,CEF,COT
Acinetobacter
-nosocomial respiratory infections
-moist environment (contamination of respiratory therapy equipment
-normal oropharyngeal flora
- AMG, IMI, AMI
Bordetella pertussis – whooping cough, pertussis
Boredetella parapertussis – parapertussis, like pertussis
Bordetella bronchiseptica – respiratory in animals,
occasionally in hum.
Franciscella tularensis – tularemia, zoonosis
Brucella melitensis – brucellosis, zoonosis
Brucella abortus Brucella suis, Brucella canis - brucellosis
Bordetella
Strictly aerobic, 3 specimens – different growing characteristics and
biochemical reactivities and antigenic properties - very similar
Differing in expression of virulence factors:
Bordetella pertussis – very fastidious, antigenic, virulent.
Bordetella parapertusis
Bordetella bronchiseptica
Bordetella pertussis – very fastidious, antigenic, virulent.
Pathogenesis – exposure to the bacteria and its attachment to the ciliated
epithelial cells of bronchial tree, proliferation of bacteria, production of
tissue damage, systemic toxicity
Pertussis toxin – 2 subunits A(active) multiple biological act., B(binding)
Filamentous hemaglutinin – attachement, hemaglutination -protective Ab
Adenylate cyclase toxin – interference with immune cells (inhibition)
Tracheal cytotoxin – ciliostasis,
Dermonecrotic toxin – vasoconstriction, tissue damage
LPS - endotoxin
Epidemiology
Person to person
Immunised population – whole cell vaccine
Inadequately immunised children – risk
Clinical syndromes
Inhalation of infected droplets – catarrhal stage (1-2 weeks) – common
cold sy – paroxysmal stage (2-4weeks) - extrusion of ciliated epithelial
cells – whooping cought paroxysms – restricted airways by mucus –
vomiting, lymphocytosis – convalescent stage – diminishing paroxysms
- secondary complications.
Laboratory diagnosis – sensitive to drying, fatty acids in cotton are
toxic, transport media or directly inoculated to Bordet Gengou plate
Fluorescent microscopy,
Humidified chamber - prolonged incubation – 7 days
B.pertussis - sampling and cultivation
• Sample from nasopharynx - on bound wire, humidity. Coughing plates
- overgroth of contaminating flora - (Blood agar + active charcoal
+ATB, or Bordette Gengou)
Bordetella pertussis – nutritionally very requiring, virulent.
Pertussic toxin – 2 subunits: A (active) multiple biological effects,
B(binding) Dermonecrotic toxin – vasoconstriction, tissue
destructione Filamentous haemaglutinin – attachement,
hemagglutination -protective Ab, Adenyl cyclase - toxin – interference
with immunity cells (inhibition), Tracheal cytotoxin – cilliostasis, LPS
- endotoxin
Laboratory diagnosis Sensitiveto drying, fat acid in cotton of
sampling devices are toxic, not living in common transport media,
direct innoculation on Bordet Gengou plate. Humid chamber prolonged incubation – 7 days
Serology -Agglutination: patient serum + Ag B. pertussis - 2 samples
in 14 days interval, 4 fold increase of titer, conversion from negat to
pozit
Treatment
-supportive, nursing supervision, ATB does not ameliorate the state –
intoxication and destruction of epitelium
-ERY – eradication of bacteria, reduction of infectiosity
Prevention
whole cell vaccine ( combine with diphteria, tetanus and Hib or HB)
associated complication
Acellular vaccine – imunogenicity ?
Serological diagnosis
Aglutination : patients serum + commercial Ag of B. pertussis
2 samples in 14 days interval, fourfold increace of titer.
Legionella
• 1976 – sever pneumonia of legionnaires – unknown Grod – faibly stainable ( impregnation with silver) , not
growing on common media (nutrtiously very fastidious requiring Fe salts and cystein)
• Everywhere present water saprofyt and human pathogen
of respiratory system
• Several taxonomic groups 14 – medically important
• Short coccobacilli, pleiomorfic, motile, catalase +,
• Legionella pneumophila – most important
Legionnaire´s disease
• Inhalation of infektious aerosol,
i.c. parasit – able to grow and multiply in makrophages,
inhibition of fusion of fagolysosomes
proteolytical ensymes - fosfatase, lipase, nuclease. Cell
imunity! ( immunocompromised - transplanted) or lung
diseases (smokers)
• - climatisation devices, showerse – prolonged stay in
closed contaminated humid environment – summer,
autumn,
• Flu like disease Pontiac fever
• sever pneumonia with multiorgan involvement
Legionnaires disease
Legionnaire´s disease - diagnosis
.
Fluorescence with labeled antibodies,
Cultivation - cystein, Fe, pH 6,9, ATB against
contaminating bacteria 35*C, 3-5 days, - identification
based on the growth on special media
Detection of antigen ( sputum or urine – present more
than 1 year – sensitive, not specific
• Serological dg – detection of antibodies - titer above
256, longlasting persitence
• Therapy – not tested routinely, ERY, RiF,
Fluorochinolon, not betalactmes
Franciscella tularensis – tularemia,glandular fever, rabbit fever
Microbiology: Nonmotile, nonpilliated, lipid capsule, fastidious growth,
prolonged cultivation (2-3 days) enriched media
Immunity:Intracellular parasite surviving in macrophages of RES
antiphagocytic capsule in pathogenic strains
endotoxin activities
Epidemiology: Worldwide distribution – wild annimals, domestic
annimals, birds, fish, arthropods contaminated water. (rabbit, thicks)
Bite of infected arthropod (present in feces not saliva – prolonged
feeding time)
contact with infected annimals consumption of infected meat or water,
inhalation of aerosol ( less than 10 organisms when bite, 50 organisms
when inhaled and 106 when ingested)
Endemic – when the rabbit is so slow as to be shot or caught it is likely
to be inficted.
Clinical syndromes 3-5 days incubation, fever, chills, malaise, fatigues,
clinical classification according to the site of infection, skin ulcers,
lymfadenopathy:
- ulcerogladular, glandular,typhoid, oculogladular, oropharyngeal,
pneumonia
Laboratory diagnosis – extremely hasardous (can penetrate cross the
skin and mucus)
Microscopy – from ulcers:small, stains faintly, fluorescein-labelled Ab
Cultivation – chocolate lbood agar with cystein. Lab should be notified.
Identification – aerobic, catalase positive, oxidase negative, agglutination
Serology – 1 serotype only. Titer above 160 is suspected. (Cross
reactivity with Brucella)
Treatement
STM, GEN,
TTC, CMP – relapses,
beta lactamase production
Prevention and control
attenuated and inactivated v.-ineffective
avoid the reservoirs
Yersinia
• 7 species - Y.pestis, Y. pseudotuberculosis, Y. enterocolitica, +
oportunistic Yersíniae
• Y. pestis - plague - urban and forest type, not GIT disease.
Adapted to i.c. parasitismus, not surviving in nature. Virulence
factors - i.c. surviving, , polysaccharide capsule, endotoxin, .
Urban plague - circulating between rats, transmitted by insect to
man during rodent bacteraemia. Replication in colon of insect and
transmission to other rodent or man is on by chance.
Forest pôague - Not controlled.
• 2 clinical formes - bubonic - 7 days after biting by insect - painful
lymphadenopathy75% lethality
- pneumonic - 2 days after inhalation - fever, pneumonia,
inhalation spread by droptets, epidemia letality 90%
flea
Brucella
• 6 species - 4 involved to human disease- brucelosis B. abortus, B. melitensis, B. suis, B. canis.
• Brucellosis – many names acc. to the place of discovery or the
person –
Bangdisease nemoc,
Mediteranean fever
Undulating fever.
Nonmotile nonencapsulated G- kokobacilli, slowly growing, very
fastidious,
Intracelular pathogen, in RES cell
Most virulent - B. mellitensis
World wide, annimal source
• B. mellitnesis – goat, sheep
- sever acute disease with complication ,
very common
• B. abortus - cattle – mild infection with
pyogenic complications, not common
• B.suis - pig – pyogenic destructive chronic
• B.canis - dog – mild pyogenic complication
• Brucella – predilection place - tissue with
erythriol (in annimnals uterus, placenta,
epididymis, mammalian gland) - sterility,
abortus in annimals. Not in human
Clinical sy, dg and therapy
• Transmission from annimal (vet doctors) or food (not pasteurised
milk) or lab.infection ( direct contact or inhalation)
localised abscess - bacteremia – localised in RES (spleen, liver, bone
marrow, lymfocytes, kidney) - granulomea
Subclinical
subacute, chronic – general symptomes not specific . Undulant fever
Several sampling of material for serology or hemocultivation
Cultivation on enriched media, for 4 weeks
Th – TTC+ GEN, prolonged application of COT
Brucelosis
Other G- rods
• Eikenella
• Calmnobacterium
• .......
Physiology and structure of
Enterobacteriaceae
• G- rods, usually motile (flagella, not spore forming, facultative
anaerobes, nutritionally not requiring, biochemical active
catalase +, oxidase -, cytochromoxidase COX - = dif.dg.from
Pseudomonadaceae
• Lactose fermentation + or -, rezistence to bile salts, capsule - dif.dg
from other Enterobacteriaceae
• 3 types of antigens:
• - somatic O antigen - most important cell wall ag, heatstabile, LPS
lipopoly saccharide consists of 3 parts - O polysaccharide, core
polysaccharide and lipid A - with endotoxin activity
• - capsular K antige - heatlabile cross reacting with antibodies against
other bacteria. In Salmonella typhi under name of Vi antigen
• - flagellar H antigen - heatlabile, antigen and phase variation
• G- aerobe rods
• 1) Facultatively anaerobic fermenters:
Enterobacteriaceae - E. coli, Salmonella, Schigella, Enterobacter,
Citrobacter, Serratia, Klebsiella, Proteus, Morganella, Providencia
Vibrionaceae - Vibrio, Aeromonas, Plesiomonas
Campylobacter, Helicobacter
• Widest and most heterogenous group of medically important bacteria
• 27 genus, 102 species (95% medically important ones belong to 25
species) - differentiation based on DNA homology, biochemical
properties, antigen characteristics, ATB susceptibility
• Commonly present in nature (soil, water, plants), parts of
physiological flora of colon.
• Obligatory pathogenic (Yersinia pestis), oprtunistic pathogens
(Klebsiella, E. coli, Proteus)
• Transmission from annimals (Salmonella), from human carrier (S.
typhi), endogenous infection (E.coli)
Sites of infections
•
•
•
•
CNS - E. coli
URT infections - Klebsiella, Enterobacter, E. coli
Septicaemia - E. coli, Klebsiella, Enterobacter
GIT infections -Salmonella, Shigella, Yersinia,
E.coli
• Urinary tract infections - E. coli, Proteus,
Providencia, Klebsiella
•
•
•
•
•
•
•
•
•
Factors of pathogenicity and
virulence
Endotoxin
Capsule
Antigenic variation
Production of exotoxin
Adhesins
i.c. surviving and multiplication
competition for growth factors
Resistence to bactericidsal activity of serum
resistence to ATB
Biological effect of endotoxin
• Part of G- bacteria cell wall - released after its destruction by ATB
• Fever
• leukopaenia followed by leukocytosis
• activation of complement
• Thrombocytopaenia
• Disseminated intravascular coagulopathy DIC
• decreased periferal circulation and perfussion of big organs
• shock
• Present in GIT
E. coli
• causes - endogennous infections after breaking of immune barieres from
physiological flora ( z focus in UGT or GIT, most important cause of G- sepses),
Infection of urinary tract (most out patients infections - rises from GIT strains,
specific serotypes binding with specific adhesis to epitel receptors),
- gastroenteritis
- neonatal meningitis
• enterotoxigen ETEC - production of heatstabile and heat labile toxin, mild water
diarhoea, travellers diarhoea,
• enteroinvsive EIEC - spread to epithelial cell of the colon, destruction of epithel,
fever, blood and leu in stool, Confirmation of invasivness - Sereny´s test innoculation of strain do conjunctiva of annimal- results in inflamation
enteropathogenic EPEC - serious child diarhoea , shiga-like toxin, able to adhere
to erytrocytes
• enterohemorhagi EHEC - production of verotoxin. From non complicated
diarhoea to hemorhagic colitis and . Hemolytic-uremic sy - type 0157:H7, - acute
kidney insufficiency, trombocytopaenia, in children under do 5 r.
Salmonella
• 1500 serotypes, different names according to place of identification
• DNA analysis = 1 species (S. enterica) and its 7 subgroupes
• Present in annimals, spread by contaminnated food - primary from
contaminated annimal products - eggs - salmonella disease of hens.
Secondary - from carrier or patients. Need of big innoculun 106-8 spread by food where it can multiply
• Salmonellosis - enteritis - infection of colon, fever, nausea, vomiting,
headaches. Dg.: Stool sample 3 x consecutively. Lactose negative
colonies, biochemical identifiction. Serotyping by slide agglutination
according to Kauffmann White scheme - epidemiological purposes
(S. enteritidis, S. infantis, S. agona, S. kentucky…………………….)
Salmonella typhi
• Typhoid fevers - fever with deterioration - systemic
disease - penetration to lamina propria, lymphatic nodes,
RES (multiplication in hepari - spread via bile vesicle to
intestine - , spleen, bone marrow), blood - bakteraemia,
exanthem - roseola, fever, headache. GIT symptomes not
always present - perforation . Carriage of Salmonella.
• Dg. - sample of stool, repeated after stimulation by
MgSO4. Typical lood of cultivation. Serotypisation by slide
agglutination. Detection of antibodies Vidal reaction. Vi
agglutintiona
• Th. - CMP
• Salmonella paratyphi A, B, C - Typhus like, milder
Shigella
• 4 species - Sh. dysenteriae, Sh. flexneri, Sh. boydii, Sh.
sonnei a 38 serotypes
• Dysentheria - watery diarhoea with blood, often
epidemic, transmitted with contaminated hands.
Surviving in water 6 months. Small infectious dosis 200 bacteria. Disease of small intestine first withou
invasion. Production of enterotoxin - invasion and
destruction of epitel, ulcers formation - pus and blood
in stool
• Dg. Based on biochemical activity - characteristics of
cultivation - without smell, not gas, lactose negative.
Serotype differenciation - slide agglutination
Yersinia
• 7 species - Y.pestis, Y. pseudotuberculosis, Y.
enterocolitica, + oportunistic Yersíniae
Yersinia enterocolitica
• Enterocolitis in colder environment, most
activity in 22*C, food borne infection,
diarrhoea, fever. Chronic disease - terminal
ileum, mesenteritis immitation of appendicitis.
Extraintestinal symptomes - arthritis, hepatitis,
osteomyelitis • Dg. - cultivation or serology by agglutination in
extraintestinal sy
• blood borne infection - bacteraemia and
endotoxic shock (blood cans - cooled)
Klebsiella
• G- rod with typical structure
• Encapsulated– mucous look of colonies - increased
virulence, notmotile
• Klebsiella pneumoniae – pneumonia in patients not able
to clean from bronchial stroma and lungs the aspirate
Necrotic destrukction of alveols. Bloody sputum.
Infection of tissue and urinary tract
• K. rhinoscleromatis - sclerom
• K. ozaenae – atrofic disease of nose musous membrane
Proteus
• Motile G- rod, Rauss phenomen
• P. mirabilis – infections of urinary tract,
production of ureasea ( lysis of urea,
alcalinisation, increased possibility for calculli
formation, toxicity for epitelium
• Proteus vulgaris
Ostatné Enterobacteriaceae
• G-, okrem Klebsielly bičíkaté – pohyblivé, niektoré
opúzdrené, virulencia závisí často na prítomnosti pili –
prichytenie – testovanie hemaglutináciou
• Koliformné baktérie – E.coli, Klebsiella, Serratia
Citrobacter a Proteus, Providencia- oportunistické
patogény
• Enterálne infekcie – pri porušení eubiózy a premnožení
• Nozokomiálne infekcie – močového traktu,
chirurgických rán, krvi a pľúc.
• Infekcie v komunite – močové, infekcie při močových
kameňoch….
• U imunokompromitovaných , po ATB, iné ochoreie,
katetrizácia
Laboratory diagnostic
• growing well on non selective media
• Selective media for detection of pathogens - lactose
negative strains Salmonella, Shigella
• Biochemical identification – Hajn medium, Enterotests –
group of biochemical tests
• Serodiagnosis – detection of antigenic structure –
Salmonella, Shigella, E.coli
• Interpretation of results
– in stool sample – Salmonella, Shigella, Yersinia –
pathogens, other enterobacteriaceae – according the the state
of eubiosis, when overgrowth
- from physiologically sterile materials: urine – UTI,
ascendent infection, blood – most improtant etiological
agens, wounds, sputum – in monoculture, nose and throat
sample - monoculture
• Endotoxin - aktivita sídli v časti lipid A, uvoľnený po lýze bb.,
príčina systémových manifestácií
• Púzdro - K antigén, zábrana fagocytózy
( hydrofilný kapsulárny Ag proti hydrofóbnym fagocytom), zakrýva
antigény bb. steny (bráni naviazaniu protilátok proti stenovým ag),
slabý imunogén, slabý aktivátor C´. Zábrana baktericídnej aktivity
séra
• Antigénne variácie - genetická expresia antigénov môže zlyhať,
antigény sa nevytvoria, protilátky nemajú s čím reagovať.
• Tvorba exotoxínov - shiga, shiga-like = AB toxiny, hemolyzíny,
termostabilné a termolabilné enterotoxíny
• Adhezíny - fimbrie (P fimbire, S fimbrie,,,,,)
• Intracelulárne prežívanie
• Vychytávanie železa - tvorbou vlastných kompetitívnych Fe
vychytávajúcich zlúčenín, uvoľňovanie Fe z hostiteľskej bunky
hemolýzou
Vibrionaceae
• G- curved rods aerobe and anaerobe growth. Present in
water
• Oxidase test – posit. – diff. Dg from Enterobakteriaceae
• V.cholerae - gastroenteritis
• V. parahaemolyticus - gastroenteritis
• V. vulnificans – bakteraemia, infection of wound,
celullitis – exposition to contaminated water, GIT – row
sea fruits
• V. alginolyticus – infection of wound and soft tissue, otitis
externa
• Other vibrias – infection of wound and moderate GIT infections
• Plesiomonas – GIT infections from raw sea fruits
• Aeromonas – opportunistic (…pijavice, after microsurgery)
V. cholerae
• Growing in 18* - 37*C
• Serologically – 6 groups based on O antigen (patogennic are O1)
• Vibrio cholerae O1 – 2 biotypes – el tor a cholerae and each present in
2 serologic subgroupes – ogawa a inaba
• Adherence, not invasive.
• Production of AB toxin – cholera enterotoxin – binding on specific
receptors of intestin, causing secretion of Na, K a bicarbonate to
lumen – liquid lost - 1 liter in hr. (hypovolaemia, arythmia, kidney
insufficiency). Not adhering bacteria are avirulentné
• In waters of Asia, human carriage and sea annimals. Spread by
contaminated water and food. Necessity of big innoculum – 103-5.
Less in condition of patients achlorhydria ( 104 bacteria after
bicarbonate)
Diagnosis and therapy of Vibrio
• Microscopy – small, motile – native smear or
darkfield
• Cultivation – selective media – not supporting
acid environment and drying– enriche alkalin
buillon pH 8,6
• Dif. dg. V. cholerae a other vibiras
(halofile, requiring 1%NaCl)
• Therapia V. cholerae – ATB for debacilisation
only, exotoxinu. (TTC,ERY, CMP, COT).,
symptomatic - solution replacement V.
parahemolyticus – mild disease, would infection –
ATB – TTC)
Campylobacter
Comma shape, G-, motile, 11 species,7 subspecies
Requiring microaerophil defined environment, 42*C,
passing through bacterial filters - selective isoloation
Campylobacter jejuni – gastroenteritis in patients with
decreased immunity –hypogamaglobulinemia, decreased
acidity of stomac liquid. Infection of epitel of jejunum,
ileum and colon results in oedematous , bloody mucus
with abscess formation.Infiltration to lamina propria.
Enterotoxin, cytopatic toxin, endotoxin. Poultry, food
neutralising pH reduced infection dosis.
C.coli - gastroenteritis, C. fetus – septicaemia, artritis,
trombophlebitis, meningitis
Lab dg.: cultivation on selective media, microscopy - of
stool - leu, antigen detection, Th.: ERY
campylobacter
Helicobacter
• Spiral rods, G-, in connection with gastritis, gastric and
duodenal ulcer, susp.Ca – Gastrospirillum hominis
• Pathogenesis – production of urease – formation of
cloud of NH4, that protects bacteria from acid in
stomac - motility - mucinase formation – spread to
mucous layer - adherence – attachment to intracelular
junction – inflamation with mononuclear infiltration in
lamina propria.Escape to IgA specific antibodies
because of its location in mucous layer
• Interhuman transmission
• Th. ATB . Bismuth, nitroimidasol a amoxicilin or TTC
Laboratory diagnosis
• Biopsy taken during endoscopy: Microscopy –
hematoxylin eosin staining, Gram staaining. !
Desinfection and contamination of endoscopic
devices
• Detection of alkalic metabolits of urease activity.
Rapid testt – 1-2 hrs – from bioptic material or
breath test
• Cultivation - from bioptic material – enrichee
media – blood, haemin, charcoal - problems:
activity of inhibition caused by desinfection of
endoscopes
• Serology: Detection of IgA ! Interpretation –
prolonged presence not discriminating between
acute and pass infection.
helicobacter