Gram Negative Cocci PDF

146 Gram Negative Cocci 4. Bacterial meningitis- CSF a..+neutrophils NEISSERIA AND MORAXELJ.A b. t" glucose 1. Key c...

146 Gram Negative Cocci 4. Bacterial meningitis- CSF a..+neutrophils NEISSERIA AND MORAXELJ.A b. t" glucose 1. Key characteristics c..+protein a. Diplococci (kidney bean shape) b. Oxidase positive 5. Moraxella (Branhamella) catarrhalis a. Respiratory infections 2. N. gonorrhoeae b. Grows well on chocolate and BAP a. Grows on chocolate and Thayer- but n ot on MacConkey's Martin (contains vancomycin, c. Colony hard and "moves over"; colistin, nystatin, hemoglobin and asaccharolytic isovitalex) d. Usually beta lactamase positive b. Requires 5-10% CO2; may take 48 e. DNAse positive hrs for growth c. Ferments glucose 6. Acinetobacter species d. Gonorrhea a. Emerging pathogen ❖ Sexually transmitted b. Respiratory infection s, UTI , or ❖ May be asymptomatic; may he colonizer mixed with Chlamydia c. Coccobacillus ❖ Gram stain sensitive for males, d. Resistance to many drugs; AST but NOT for females required ❖ May be confused with Moraxella e. Identification or Acinetobacter ❖ Growth on MAC ❖ Do NOT refrigerate prior to ❖ Some h emolytic culture ❖ Oxidase negative ❖ Penicillin or spectinomycin sensitivity; perform bet·a lactamase test to determine penicillin sensitivity @Diffe~~~~~seria e. Most ID by probe technology Glucose Maltose Lactose Neisseria gonorrhoeae N. gonorrhoeae + Gonorrhea, the clap, GC N. meningitidis + + I'm an old-fashioned STD. + N. lactamica + + I need co2 and chocolate All ferment glucose; g_onorrhoeae: only glucose; agar meningitidis: glucose and maltose; and And may not grow for 48 factamica: glucose, maltose and lactose. hours. Gram Positive Rods I ferment glucose, the only sugar for me, CORYNEBACTERIUM DIPH1HERIAE Do an oxidase and purple you'll see. 1. Key Characteristics a. Small pleomorphic rods with 3. N. meningitidis clubbed ends a. Grows on blood agar , chocolate and b. Palisade or "chinese letter" Thayer-Martin arrangement b. 5-10% CO2 enhances growth c. Metachromatic granules (stain c. Ferments glucose and maltose red-purple wit/1 methylene blue) d. Transmitted by respiratory droplets d. Tinsdale agar - black colonies due and requires close contact to tellurite hydrolysis e. Meningitis e. E lek test - determines toxin ❖ Seen mostly in children under 3 production by the isolate in vitro ❖ Waterhouse - Friderichsen syndrome (sca ttered petechiae) = 2. Loeffler' s - enhances development of meningiococcemia m etachromatic granules ❖ Ma.inly caused by types A, B, C, Y a. Pallisade arrangement may be seen &W  147 3. Exotoxin production b y only lysogenic ERYSIPELOTHRIX organsims carrying a B phage 1. Key Characteristics a. Non-motile 4. Produces pseudomembrane on tonsils, b. Catalase negative uvula or soft palate c. "Test tube brush" growth in gelatin; 5. Causes diphtheria H2S positive in TSI GARDNERELLA VAGINALIS 2. Occupational infection for fishermen, 1. Bacte1·ial vaginosis butchers, veterinarians, rose grower s BACILLUS SP. (Sporeformers) 2. "Clue cells" - high number of squamous epithelial cells colonized with 1. Key Characteristics gram variable rods a. Large, ground glass colonies b. Some beta hemolysis (But not B. 3. 10% KOH added to discharge causes anthracis) "fishy" odor c. Catalase positive d. Large gram positive to variable rods 4. Tiny colonies at 48 hrs on BAP and in chains with spores chocolate 2. B. anthracis 5. Catalase and oxidase negative; a. Very long chains ("bamboo shoots'') hippurate and starch positive b. "Medusa h ead" colonies LISTERIA MONOCYTOGENES c. Non-motile, non-hemolytic 1. Key Characteristics d. Anthrax - cutaneous, pulmonary, or a. Small colonies with narrow zone of gastrointestinal beta hemolysis 3. B. cereus - Food poisoning due to b. Catalase positive preformed toxin - "fried rice" c. Tumbling motility; "'umbrella" motility in SIM at r oom temperature but NOT 37°C d. Bile esculin positive 2. Causes neonatal meningitis and sepsis; sepsis in immunocompromised hosts Gram Positive Rods ORGANISM CATALASE ESCULIN H2S /TSI ~ HEMOLYSIS NOTES Corynebacterium + - - +/- "Chinese Letter" Arrangement; r'1) ~ Metachromatic Granules (Loeffler's Slants); Tellurite Hydrolysis ti ~ (Tinsdale Agar); Elek Test Determines Toxin Production Listeria + + - + Tumbling Motility at 250 C, but Not ~ 37C; Cold Enrichment; Neonatal Meningitis and Sepsis; Sepsis in lmmunocompromised Hosts El}',~sipelothrix - - + - 'Test Tube Brush" Growth in Gelatin; Infection in Fishermen, , , Butchers, Veterinarians Bacillus (Spore Formers) + V - - I+ "Ground Glass" Hemolytic Colonies; l)il ~ a D ti rn B. anthracis -Non-Hemolytic, Non-Motile, "Medusa-head" colonies (filamentous outgrowth) B. cereus- betahemolytic, motile , large flat colonies (irregular edges) 148 Gram Negative Rods ❖ Food poisoning associated with ENTEROBACTERIACEAE undercooked meat (hamburger) ❖ Hemolytic uremic syndrome 1. General Characteristics (HUS) a. Peritrichous flagella when motile b. Ferment glucose 4. Kl strains can cause neonatal meningitis c. Reduce NO3 to NOz d. Most oxidase negative Shigella e. Antigens used in typing: 1. Key Ch aracteristics ❖ Flagella = H Ag a. Lactose negative ❖ Envelope = K Ag b. Non-motile ❖ Cell wall LPS c. Anaerogenic (lipopolysaccharide) = 0 Ag ❖ All possess LPS endotoxin; some 2. Bacillary dysentery - penetrate produce exotoxins epithelial cells in small intestine Escherichia coli 3. S. dysenteriae (Group A)- most severe 1. Key Characteristics 4. S. flexneri (Group B) a. Indole and lactose positive b. IMViC = ++ - - 5. S. hoydii (Group C) 2. Most common cause of UTI in females 6. S. sonnei (Group DJ- most common 3. Intestinal infections 7. < 200 organisms needed for disease a. Enterotoxigenic E. coli (ETEC) ❖ LT toxin (heat labile) ❖ ST toxin (heat stable) b Enteroinvasive E. coli (EIEC) ❖ Penetrate epithelial cells in large REMEMBER! intestine Shigella ❖ May be lactose negative c. Enterohem or r hagic E. coli (EHEC) S. dysenteriae = Group A (1st alphabetically) - strain 0157:H7 S. flexneri = Group B (not "B"oydii) ❖ Sbigella-like toxin S. boydii = Group C ("boyd ee ee" = "C'J S. sonnei = Group D (last alphabetically) Common Gram Negative Selective Media AGAR DIFFERENTIATING SELECTIVE H2S LACTOSE LACTOSE AGENT AGENT INDICATOR POSITIVE NEGATIVE MAC Lactose Crystal Violet, None Dark Pink Transparent MacConkey Bile Salts EMB Sucrose Eosin Y None Green Sheen, Transparent (Eosin, Methylene Blue) Lactose Methylene Blue Purplish and Brownish Amber HE Lactose Bile Salts Sodium Thiosulfate Salmon Green to Blue (Hektoen-Enteric) Sucrose (H:zS+ = Black) Salicin ss Lactose Brilliant Green Sodium Thiosulfate Red Transparent (Salmonella - Shigella) Bile Salts (H:zS+ = Black Center) XLD (Xylose - Lysine Lactose Bile Salts Sodium Thiosulfate Yelrow Transparent on Deoxycholate) Sucrose Red Medium Xylose (H:zS+ = {;Jlack) Enrichment Broths = Selenite and GN Broth  Enterobacteriaceae: Primary Differentiating Tests TSI Ornithine VP Urease Lysine Motility H2S Deaminase DNAase Citrobacter K(A)/A, Gas V - V - + V - - Enterobacter A/A, Gas + + - V + - - - Escherichia - A(K)/A, Gas V - + V - - - Klebsiella A/A, Gas - + V + - - - - Morganella KIA, Gas + - + V + - + - Proteus KIA, Gas - - V + + + + V Providencia KIA, Gas - - V - + - + - Salmonella KIA, Gas - - + + + + - - Serratia K(A)/A V + - + + - - + Shigella KIA V - - - - - - - Plesiomonas KIA + - - + + - - - v = variable I * oxidase positive Shaded areas = Key reactions differentiating similar genera I · 1tsrP_e~r ~ ~ & - ~ --L) ,., "" ~ ,_ _.,.. \0 150 Klebsiellae Citrobacter 1. Opportunist; UTI , pneumonia ; 1. Opportunist ampicillin-r esistant 2. Lysine negative 2. Kleb siella a. Non-motile 3. Similar to Salmonella biochemically b. Has capsule Proteus c. Ur ea variable 1. Key Characteristics d. Ornithine negative a. Urea positive e. VP positive f. Can cause lobar pneumonia b. Deaminase positive g. New member: K. granulomatis 2. P. mirabilis ❖ Formerly Ca.lymanatohactedum a. Most sensitive to penicillins ❖ STI b. Indole negative 3. Enterohacter 3. P. vulgaris a. Motile a. Indole positive b. Ornithine positive b. H2S positive 4. Serratia Yersinia a. May produce r ed pigment 1. Y. enterocolitica b. DNase, gelatinase positive a. Optimal growth = RT; cold enrichment c. VP positive b. Invasive and toxigenic Klebsiella 2. Y. pseudo tuber culosis - Acute mesenteric pn.eumoniae lymphadenitis and "pseudotuher cules" Kleb pneumo in 3. Y. p estis - bubonic plague lungs, where Plesiomonas else would I be? 1. Oxidase positive Maybe in a wound, bladder 2. Reclassified into E11ter ohacteriaceae or kidney. 3. Lophotrichous flagella I hove no flagella and I can't swim. 4. Associated with diarrheal disease Test this out with S-1-M. BIOCHEMICAL TESTS I'm blue on citrate, prefer lysine. 1. Oxidase test Maybe pink on urea, hate ornithine. a. Reagent tetramethyl p- Salmonella phenylenediamine dihydrochloride b. Positive = purple 1. Large number needed for infection (> 100,000) 2. Nitrate test a. Reagen ts - a-naphthylamine, 2. Biochemical r eactions sulfanilic acid a. H2S positive b. Positive= pink (use zinc powder to b. Lysine positive confirm) c. Indole negative d. Urea negative 3. ONPG test a. Detects B-d-galactosidase 3. S. enterica- >2000 serot yp es including b. Reagent - O-nitrophenyl-B-d- a. S. cholerasuis - septicemia galactopyranoside b. S. typhi - typhoid fever c. Positive = yellow ❖ B.lood positive early - 1st week ❖ S too.l positive late- 2nd-3rd week 4. TSI (triple sugar iron agar) slant c. S. arizon e - ONPG pos (other s n eg) a. 0.1% glucose, 1% sucrose, 1% lactose b. Yellow butt - glucose fermented c. Yellow slant - lactose or sucrose fermented