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Practical taxonomy. Miscellanous bacteria. Mycoplasma, Ureaplasma, Chlamydia Ricketsiaceae Spirochetales - Spirochetes, Leptospira, Borrelia Mycobacterium Nocardia , Actinomycetes, . Genus:Bacillus - G+sporeforming bacilli, aerobic and facultatively anaerobic.
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Practical taxonomy Miscellanous bacteria Mycoplasma, Ureaplasma, Chlamydia Ricketsiaceae Spirochetales - Spirochetes, Leptospira, Borrelia Mycobacterium Nocardia , Actinomycetes,
Genus:Bacillus - G+sporeforming bacilli, aerobic and facultatively anaerobic • Bacillus anthracis,Bacillus cereus,Other Bacillus sp. • Bacillus cereus - 2 enterotoxins - heat stable - emetic form - contaminated rice - heat resistant spores survive initial cooking that kills vegetative cells, germinate, multiply and toxin is not destroyed by reheting - heat labile - diarrheal form - adenylcyclase-cAMP system stimulation in intestinal cells - fluid accumulation -contaminated meat and vegetable - toxin is produced in situ, longer incubaion • Panophthalmitis - traumatic eye infection (soil, penetrating object), complete loss, massive destruction - toxins - necrotic - heat labile enterotoxin - cereolysin - hemolysin - phospholipase C - lecithinase • Ubiquitous, isolation witout symptoms = contamination • Other Bacillus - immunosupressed patients - shunt and catheter inf.
Bacillus anthracis • Spore and capsule (protein) not seen in clinical specimens • Antrax toxin - 3 antigenically distinct components: -protective Ag, lethal factor, edema factor - not active separately, • Pathogenesis: capsule - antiphagocytic, Ab are not protective, toxins are active in cooperation of: protective + lethal or edema f. • Cultivation - on nonselective media, rapidly growing adherent colonies, no hemolysis, Non motility,liquifaction of agar Microscopy: caput medusae – serpentine like chains,
Bacillus anthracis • Human diseases - cutaneous - inoculation - painless papule, ulcer, necrosis - respiratory - inhalation - rapid progresive diffuse pulmonary involvement - respiratory failure - 95% mortality - gastrointestinal - ingestion - rare - mesenteric adenopathy, hemorrhage, ascites, 90% mortality • Therapy - PNC (TTC, CMP)., control of animal antrax, vaccination.
Non sporeforming G+ bacilli - heterogenous group • Corynebacterium - coryneforms, diphtheroids- C. diphteriae (diphtheria), C. jeikeium (oportunistic). C. urealyticum(urinary tranct inf.), C. pseudodiphthericum (endocarditis), C. ulcerans (pharyngitis) • Arcanobacterium haemolyticum - pharyngitis • Actinomyces - granulomatous ulcerative inf. • Rhodococcus - suppurative pneumonia, opportunistic • Listeria - meningitis, septicemia, granulomatosis infantiseptica • Erysipelothrix - erysipeloid, septicemia, endocarditis • Gardnerella - bacterial vaginosis
Corynebacterium • Pleoimorphia, G+rods, forming short chains, china letters, or letter Y,V - forms • Metachromatic granuls – resulting colour differs from the colour of the used one • Special cell wall structure – mesodiaminopimelic acid, arabinogalactan, mycolic acid with short chains – taxonomic neighbour to mycobacteria • C. diphtheriae – preventabil disease diphthteria • asymptomatic carriage in pharynx droplet transmission • C. jeikeium - JK - oportunistic patogen in immunocompromised - hematological disorders • Others - transmitted from annimals
Corynebacterium- patogenesis and immunity • Diphtheric exotoxin - tox gen can be transmitted to bacteria (C. diftérie, C. ulcerans, C.pseudotuberculosis via bacteriophage – lysogenic conversion • A-B protein: B phragment – binding on the cell surface enable enter of A phragment to the cell. A phragment is enzymatically active - blocking synthesis of proteins – prolngation of peptid chain on ribosomes • Skin test – detection of neutralising antibodies in vivo - i.d. application of diphtheric toxin
Phospholipase D - dermonecrotic toxin – enable spread by increasing vascular permeability . ulcerans, C. pseudodiphthericum • Urease - C. urealyticum – alkalinisation of urine and urine calculi forming • ATB resistence –selection of resistent strains - C. urealyticum, C. jeikeium – resistent to commonly used ATB in UT infection
Diphtheria • Clinical presentation depends on state of immunity and place of infection: - asymptomatic colonisation, mild respiratory infection, fulminant diphtheria • Difphtheria – URT infectionwith low grade fever, toxin induce local damage adherent pseudomembrane on tonsils, pharynx, nose and general symptoms of intoxication. Myocarditis. • Skin diphtheria – transmission via skin contact from infected persons, colonisation and enter via small injurie - papules and chronic ulcers with membrane and general signs of intoxication, less sever,
Laboratory diagnosis • Microscopy – detection of metachromatic granules – methylen blue staining – not important • Cultivation – on common media (blood agar), special media – Loffler medium, - tellurit agar – gray brown colonies • 3 types of colonies - gravis (big, irregular, gray), mitis (small, convex,round, black), intermedius (small, plate, gray) – connected with importance and virulence – not considered more • Biochemical identification • Detection of toxigenicity - Elek´s test - immunodiffusion, - antitoxic test on annimal model.,
Arcanobacterium • A.haemolyticum - colonise human, responsible for pharyngitis (+/- scarlet fever-like rash), cutaneusinf., endocarditis, meningitis - in older patients • Missdiagnosed as Str. pyogenens, grows slowly, weak hemolysis • 2 toxins - hemolysin and phospholipase D • enzymes neuraminidase
Erysipelotrix • E. rusiopathiae: G+ non spore forming facultative anaerobic bacillus, worldwide distribution in animals • Cultivation in reduced oxygen athmosphere, small grayish, alfa hemolytic colonies, 2-3 days, sample from deep tissue or deep aspirates. • Erysipeloid - occupational disease (butchers, meat processors) after subcutaneous innoculatio -localised skin infection -generalised cutaneous forme -septicaemia - associated with endocarditis (undamaged heart valve - aortic) • Therapy PNC, ERY,CLI (sulfonamids, vancomycin, aminoglycosides - resistent)
Listeria • 7 species, most important L. monocytogenes – facultatively anaerobe neonporeforming G+ rod • meningoencephalitis, bacteraemia, endocarditis • New borne, older gravid women, immunocompromised patients (after transplantation • Frequently transfer via milk and row milk products, row vegetable • Able to grow in wide range of pH a and low temperature 22*C , faible beta hemolysis, motile in liquid media
Clinical syndroms • Newborne listeriosis - infection in utero - granulomatosis infantiseptica, devasting disease, diseminated abscesses and granulomes multiorgan involvement - late listeriosis - 2-3 weaks after delivery - meningitis, septicaemia • Meningitis of adults – in immunocompromised,after transplantation • Bacteraemia, Endocarditis • Dg. Microckopy of CSF usually negat.- few bacteria, Cultivation and indentification • Therapy - penicillin +/- combination with aminoglycosids
Rhodococcus • G+, obligate aerobic, red-pigmented, acid fast, mycolic acid. Veterinary pathogen. Present in soil • Intracellular - surviving in macrophages • Granulomatous inflammation with abscess formation (lung,lymph nodes, menings, pericardium, skin) - immnosupressed • Cultivation - nonselected media, aerobically, pigmented colonies after 4 and more days • Therapy : prolonged - multiple ATB able to penetrate into macrophages
Gardnerella • Morphologically resembles gram negative bacilli, has cell wall structure of gram +, nonmotile, not capsule • part of normal vaginal flora • present in bacterial vaginosis together with obligate anaerobes - Mobiluncus, Peptostreptococcus,absence of Lactobacillus. Present in postpartum bacteremia, endometritis, vaginal abscesses • Lab. dg. - simple isolation is not prooving, importance of microscopic examination - clue cells - epitelial cells covered with G variable bacilli (Gardnerella) and G- small curved bacilli (Mobiluncus), absence of G+ bacilli (Lactobacilli) • Therapy: ampicilin, metronidasol
Actinomyces • G+ filamentous rods, 5-10%CO2, • Actinomyces israeli, A. meyeri, A. naeslundii, A.odontolyticus • chronical disease with abscess, tissue destruction and sulphur granules in tissue (mass of mycelia surrounded by protein, polysaccharide and bacteria) • cervicofacial forme(endogenous, after tooth extraction) - abdominal,( starting in appendix and diverticules) -pelvic forme (from IntraUterinDevices) • hematogenous disemination • Lab. Dg. - pus with sulphur granuls - Ziehl Neelsen - microscopy, cultivation - agar with heart brain infusion - 10 days, colony shape - mollar tooth
Nocardia • G+strictly aerobe rods. Similar to quickly growing mycobacteria, saprophytes in environment. Acid fast., Mycolic acid • Nocardia asteroides, N. brasiliensis, N. madurae • pneumonia - with confluent abscess formation, exogenous inhalation • skin infection - Actinomyces brasilinensis - localised celulitis, purulent sinuses with chronical granulomatous inflamation - mycetoms • Madurmycosis - chronical granulomatous infection of bone and soft tissue, deformations, (Sudam, Northern Africa, East India) • diseminated - CNS - brain abscesses, in immunocompromised • Lab. Dg. - microscopy - modified Ziehl Neelsen, Gram +, cultivation - standard media -2-30 days, colonies adherent to agar, cream, orange rose color, chalky consistence • Therapy: surgery+ATB 3 months sulphonamids, amikacin, imipenem, broad spectrum to be effective if fungal ethiology
Anaerobic bacteriae • G+cocci polymicrobial • G-cocci endogenouse • G-rod mixture • G+rod – nonspores forming fac.patogenic – sporeforming– patogens, clinical units
G+cocci anaerobic • Peptostreptococcus, -Peptococcus,- Sarcina (fac. anaerobic) - Coprococcus, - Ruminococcus - colonisation of the skin and mucouse membrane GIT, UGT, - oportunistic patogens in connection with foreign bodies – cultivation – require special grow conditions, slowly growing Clinical symptoms - pleuropneumonia following aspiration, sinusitis, brain absces – spreading from oropharynx or lung, - intraabdominal infection and sepsis – spreading from colon, - pelvic infections (endometritis, absces, puerperal sepsis, bacterial vaginosis) - infection of soft tissue (celulitis), endocarditis, osteomyelitis • Laboratory diagnosis – colonising bacteria or ethiological agent, sampling and transport under anaerobic conditions, prolonged cultivation on enriched media • Th - PNC, cefalosporins, imipenem, CMP - polymicrobial ethiology.
G-cocci • anaerobic • Veillonella, Megasphera – present in oropharynx, low virulence, in cultivation usually part of polymicrobial mixture
G-rod anaerobic • Bacteroides fragilis obligatory anaerobic rod, not sporeforming, - most important part of fysiological flora in oropharynx, UGT, GIT. Clinical symptomes - pleuropneumonia, intraabdominal abscess, genital infections. Endogenous and polymicrobial infections, absceses after break down of physiological barieres. Lab.dg. strictly anaerobic sampling, transport and cultivation stimulation of the growth by 20% cholic acid. Th surgery intervention + ATB, - B.producesa betalactamase, Metronidasol • B(G). stearothermophilus- spores used for testing efficiency of sterilisation devices • Prevotella, Porphyromonas, Fusobacterium, Leptotricha, Wolinella – colonisation of orofarynx, GIT, UGT, part of physiological flora, pathogenic after the breakdown of natural barieresr – e.g.. Surgical intervention • They produce histolytical enzymes, • absceses and polymicrobial infection (CNS, UGT,intraabdominal) • Production of betalaktamase – resistente to PNC. • Lab. dg. Anaerobic sampling and transport, prolonged cultivation
G+rods aerobic • Spores forming - Bacillaceae - Bacillus cereus, B. antracis -flagella, facultative anaerobes or strict aerobes. Production of toxins. • Nonsporesforming - Listeria monocytogenes - motile, aerobic, surviving 22*C and broad interval of pH, infecting annimals -Corynebacteriaceae -aerobic nonmotile slightly curved, forming picture of alphabet letters, irregularly stainable – Containing metachromatic granules, production of toxin - lysogenic conversion - toxigenicita of strains - Elek´s test.Corynebacterium diphtheriae, C. pseudodiphtericum,Erysipelotrix rusiopathiae - facult. anaerobic, transmission from annimals, grey colonies, alfa hemolysis,NocardiaceaeNocardia asteroides – contain lipid in the cell wall – modified Ziehl Neelsen staining, nonmotil, filamentous form in microscopy, prolonged cultivation
G+rods anaerobic nonsporesforming • - Actinomycetaceae Actionomyces israeli, A.naeslundii Clinical signs: cerebral, cerevicofacial, abdominal, thoracal actinomycosis, chronical pyogenic infection with absceses. Lab.dg. Sampling from the depth of sinus or abscess containing sulphur granules, typical colonies looking like tooth molar, requiring, long cultivation. Th: surgery +ATB prolonged PNC -Propionibacteriaceae Propionibacterium acnes colonisation of skin, external ear, conjunctiva, orofarynx, female external genital tract. Clinical symptomes: Acne and opportunistic infections in patients with foreign bodies. Lab. dg. On common media, prolonged cultivation - Mobiluncus ---gram variable, structue of G+, curved, growth reqirements, colonisation of fem.external genital – in case of dysmicrobia - vaginosis -Bifidobacteriaceae, Eubacteriaceae,- Lactobacillaceae. –part of physiological flora
Anaerobic Gram + sporesforming rodsClostridium sp. • strictly anaerobic, spores typically localised in the cell enlarging the body, proteolytical ensymes, production of toxins, C. tetaní – tetanus – traumatic - newborne C. botulinum - botulizmus – newborne - wound - food borne C. septicum - nontraumatic myonecrosis, patients immunocompromised - Ca of colon - breakdown of the integrity of colon, spread of clostridia in tissues, hyperacute course C. difficile - pseudomembranouse colitis connected with broad spectrum ATB therapy, produces 2 toxins, part of FF, exposition to ATB taht eliminate colon bacterial flora – overgrowth of C. difficile and its spores
Anaerobic gram + spores forming rodsClostridia of anaerobic traumatoses • Clostridia - 100 species, some of them can be aerotolerantné - C. histolyticum – can looks like gram negatívne, spores not constantly detectable. Commonly present in soil, water, GIT of annimal and human. • C. perfringens - Bacteraemia, myonecrosis – gas gangrene, infection of soft tissue, necrotising enteritis
Clostridium tetani • Motile rod, spores forming, spores enlarging cell,squash rocket, transiently gram negative. Very sensitive to oxygen, metabolically very active. • Produces 2 toxins - Termolabil neurotoxin- tetanospasmin – released from lysing cells. AB toxin - blocking neurotransmitters in CNS on na inhibation synapsesh – nonregulation of excitation synaptic activity - spastic paraysis, convulsions. - tetanolysin • Present in soil and GIT of annimal. Vegetative formes are very sensitive on oxygen. Spores are surviving years Generalised tetanus, - localised tetanus, - nexborne tetanus, - tetanus of drug abusers Therapy - PNC, antitoxin, - toxin bound on synapses is not neutralisable and ATB are active agains viable cells (not toxin) Symptomatic • Vaccination
Clostridium botulinum • Heterogennous group, nutritionnaly requiring spores forming rods. 4 groups I - IV based on proteolytical aktivity a type of toxin. Producing 7 antigenically different botulotoxines A,B,C alfa, D, E, F, G - A,B,E most frequent. AB toxin , termolabil toxin - 20minutes/80*C • Blocking transmission on nervemuscular platelet on synapses of periferic nerves. Food borne, wound botulisme, infant botulisme Blurred vision, dilatation of pupils, dry tongue, constipation, bilateral muscular weakness – complete restoration after months or years Wound botulisme – very rare Infant botulisme - 1976 - in vivo production of neurotoxin in colon colonising clostridia (age of 6mnth - 1 y) – progresive paralysis, respiration failure - mortality 1% - frequently cause of SIDS Dg. - clinical, detection of clostridium or toxin Th. – lavage of stomach + antitoxin, PNC, destruction of spores and prevention of spores germination
Clostridium perfringens • Colonisation or sever disease, spores are seen scarecely, hemolysis, metabolic aktivity. • Production of letal toxins (alfa, beta, epsilon, iota, termolabil enterotoxin) with sever life threating biological activity, + ensymes. Types A-E: A in environment, B-E in colon, A gas gangrene and intoxication, C necrotizing enteritis • Microscopy - G+rods without leu in clinical samples Th – surgery in traumatoses, high doses of PNC, antitoxin, hyperbaric room for oxygen therapy
Clostridium perfringens • Bacteraemia – usually not significant, transient from skin contaminant. • Gas gangrene – life threating, histotoxic clostridia, after injury, devitalised tissue – gas production. (C. septicum, histolyticum, novyi) • Celulitis, fasciitis – after colonisation of the wound, oftently not important or rapidly progressing destruction of tissue (C. septicum) • Necrotizing enteritis –small intestine, typ C, 50% letality Food borne intoxication – short incubation time, spasmes, watery diarrhoe – ingestion of contaminated food, toxin - termolabil protein