g- negative aerobic bacilli: 1)facultative anaerobic fermenters. enterobacteriaceae - e.coli,...

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 G- rods - 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 FACTORSPilli - 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

BordetellaStrictly 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 parapertusisBordetella 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 G-

rod – 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 Prevention and control STM, GEN, attenuated and inactivated v.-ineffective TTC, CMP – relapses, avoid the reservoirs beta lactamase production

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 cellMost 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 hemocultivationCultivation 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

E. coli• Present in GIT• 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)

CampylobacterComma shape, G-, motile, 11 species,7 subspeciesRequiring 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