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G- negative aerobic bacilli:

G- negative aerobic bacilli: Facultative anaerobic fermenters . Enterobacteriaceae - E.coli, Salmonella, Schigella, Enterobacter, Citrobacter, Serratia, Klebsiella, Proteus, Morganella, Providencia, Vibrionaceae: Vibrio, Aeromonas, Plesiomonas

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G- negative aerobic bacilli:

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  1. G- negative aerobic bacilli: • 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)

  2. 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 Primarily oportunistic Structura factors and toxins – virulence factors Nonfermentative – cytochromoxidase – dif.dg. Capsule production Diffusible pigments - pyocianin, pyorubin,

  3. 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

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. 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. 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

  11. 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

  12. 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.

  13. 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.

  14. 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

  15. G-paličky • 1) Fakultatívne anaeróbne fermentujúce paličky:Enterobacteriaceae - E. coli, Salmonella, Schigella, Enterobacter, Citrobacter, Serratia, Klebsiella, Proteus, Morganella, Providencia Vibrionaceae - Vibrio, Aeromonas, Plesiomonas Campylobacter, Helicobacter • 2) Obligátne aeróbne nefermentujúcePseudomonadaceae - Ps. aeruginosa, Stenotrofomonas maltofilia, Acinetobacter, Burgholderia cepacia • 3) Haemophilus a príbuzné rody (Actinobacillus, Psteurella) • 4) Ostatné G- paličky - (Bordetella, Brucella, Legionella, Franciscella, Afipia, Bartonella, Calymmatobacterium, Cardiobacterium Eikenella, Flavobacterium, Streptobacillus, Spirillum)

  16. Vibrionaceae • G- zahnuté paličky, netvoria spóry, schopné aeróbneho aj anaeróbneho rastu. Prítomné vo vode • Oxidázový test – pozit – odlíšenie od Enterobakteriaceaei • V.cholerae - gastroenteritis • V. parahaemolyticus - gastroenteritis • V. vulnificans – bakterémia, inf. rán, celulitída – expozícia kontaminovanej vode, GIT – zjedenie surových ustríc • V. alginolyticus – inf. rán, mäkkých tkanív, otitis externa

  17. campylobacter

  18. helicobacter

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