Labquality External Quality Assessment Programmes General Bacteriology 1 3/2013

Transcription

1 Labquality External Quality Assessment Programmes General Bacteriology 1 3/2013 Photos and text: Markku Koskela, M.D., Ph.D. Clinical microbiology specialist Oulu, Finland

2 Sample 21/2013 Maxillary sinus excretion. Acute maxillary sinusitis in an adult patient Finding: Haemophilus influenzae, as a pathogen. Lab exercises: Isolation and identification of the pathogen. Antimicrobial susceptibility tests.

3 Sample 21/2013 Maxillary sinus excretion. Aerobic growth on a sheep blood and a chocolated blood agar plate in 5% CO 2 at 35 C within 24 hours. Bacterial growth only on the chocolated blood agar plate: medium, rised, grey colonies.

4 Sample 21/2013 Haemophilus influenzae A satellite test on a blood agar plate in 5% CO 2 at 35 C within 16 to 24 hours. Aerobic growth on a chocolated blood agar plate in 5% CO 2 at 35 C within 24 hours. Rised, gray colonies. H.influenzae is growing as a satellite close to a line of Staphylococcus aureus Pleomorphic Gram-negative rods

5 Sample 21/2013 Haemophilus influenzae A growth factor test on a blood-free agar plate in 5% CO 2 at 35 C within 16 to 24 hours XV-factor disk as a control. A visible growth around it must be seen. H influenzae needs both X- and V-factor to grow following that it is growing between the two disks.

6 Sample 21/2013. Haemophilus influenzae Vitek 2 NH Haemophilus influenzae

7 Sample 22/2013 Contact lens in its preservative solution. Conjunctivitis in a contact lens wearer. Findings: Alcaligenes xylosoxidans (Achromobacter xylosoxidans), as a pathogen. A coagulase negative staphylococcus species (Staphylococcus warneri) is representing the normal flora of human conjunctiva. Both of them are contaminants in the preservative solution of this patient case. Lab exercises: Isolation and identification of the pathogens. Interpretation of the findings.

8 Sample 22/2013 Contact lens in its preservative solution Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small, glistening colonies. 2. Medium, flat, yellowish-white, glistening staphylococcal-like colonies

9 Sample 22/2013 Contact lens in its preservative solution. Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small, glistening colonies. 2. Medium, flat, white, glistening staphylococcal-like colonies

10 Sample 22/2013 Contact lens in its preservative solution 2. Flat, glistening, yellowwhite staphylococcal colonies. 1. Convex, gray bacillar colonies, which are oxidase positive. Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 48 hours.

11 Sample 22/2013 Contact lens in its preservative solution. 1. Gray bacillar colonies 2. White staphylococcal colonies Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 48 hours.

12 Sample 22/2013 Alcaligenes xylosoxidans Oxidase positive Growth on a sheep blood agar plate at 35 C after 24 hours. Convex, gray bacillar colonies. Gram-negative rods

13 Sample 22/2013 Alcaligenes xylosoxidans Fermentation test results: 1) Glucose/gas -/- (green/no gas) 2) Indole - (colourless) 3) motile 4) citrate + (blue) 5) urea - (colourless) 6) TSI: red/red/no gas, H2S negative. A nonfermentative bacterium. ->API20NE

14 Sample 22/2013. Alcaligenes xylosoxidans 1. API20NE Achromobacter xylosoxidans (94,5%) Oxid + - -, - - -, - - +, - - -, - - +, + + +, Vitek 2 GN Alcaligenes xylosoxidans

15 Sample 22/2013 (16/2012) Coagulase negative staphylococcus (Staphylococcus warneri) 1 2 Growth on blood agar after 24 hours at 35 C. Yellowish-white, glistening staphylococcal colonies Staphylococcal latexagglutination test: 1. Negat (S warneri) 2. Posit (S aureus)

16 Sample 22/2013 (16/2012). Staphylococcus warneri 1. API20Staph: Staphylococcus warneri (27 %) If urea + -> Staphylococcus warneri (75 %) Urea should be positive! - + +, - + -, + + -, - + +, + - -, + - -, Vitek 2 GP Staphylococcus warneri

17 Sample 23/2013 Pus from a mandibular fistula of a 62-years-old Asiatic female. Findings: Eikenella corrodens as a pathogen. A coagulase negative staphylococcus species (Staphylococcus hominis) is representing the normal flora of the skin. Lab exercises: Isolation and identification of the pathogens. Interpretation of the findings.

18 Sample 23/2013 Pus from a mandibular fistula. Gram stain findings of the sample 1000x Gram-negative coccobacilli (weakly stained)

19 Sample 23/2013 Pus from a mandibular fistula Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small, matt, gray colonies 2. Medium, white, glistening, staphylococcal-like colonies.

20 Sample 23/2013 Pus from a mandibular fistula Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small, matt, gray colonies 2. Medium, white, glistening, staphylococcal-like colonies.

21 Sample 23/2013 Pus from a mandibular fistula Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 48 hours. 2. Flat, glistening, yellowishwhite staphylococcal colonies. 1. Small, matt, brownish, pitting colonies, which are oxidase positive.

22 Sample 23/2013 Pus from a mandibular fistula Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 48 hours. 1. Small brownish colonies 2. Flat, glistening, staphylococcal colonies

23 Sample 23/2013 Eikenella corrodens Catalase negative (not bubling) Oxidase positive Growht on a sheep blood agar plate in 5% CO 2 at 35 C within 48 to 72 hours. Small, matt, pitting, gray-brown colonies Pleomorphic Gramnegative coccobacilli

24 Sample 23/2013 Eikenella corrodens 1. RapID NH 1052 Eikenella corrodens (99 %) + - -, - - -,+ - +, Vitek 2 NH Eikenella corrodens

25 Sample 23/2013 (10/2012) A coagulase negative staphylococcus (S hominis) Staphylococcal latexagglutination test S hominis - S aureus + Growth on a sheep blood agar plate at 35 C after 24 hours. Yellowish-white, glistening, flat colonies. Gram-positive cocci in clusters

26 Sample 24/2013 Smear sample from a nipple piercing of a 24-years-old female student. Findings: Dermabacter hominis (earlier Corynebacterium hominis) and Propionibacterium acnes, which are members of the normal flora of the skin. Lab exercises: Isolation and identification of the pathogens. Interpretation of the findings.

27 Sample 24/2013 Smear sample from a nipple piercing. Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small to medium, rised, glistening colonies. 2. Others?

28 Sample 24/2013 Smear sample from a nipple piercing. Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 24 hours. 1. Small to medium, rised, glistening colonies. 2. Others?

29 Sample 24/2013 Smear sample from a nipple piercing. Growth on a sheep blood agar plate in 5% CO 2 at 35 C after 48 hours. 1. Medium, rised, glistening, gray-white colonies.

30 Sample 24/2013 Smear sample from a nipple piercing. Growth on a chocolated blood agar plate in 5% CO 2 at 35 C after 48 hours. 1. Medium, rised, glistening, gray-white colonies.

31 Sample 24/2013. Dermabacter hominis Catalase positive (bubling) Grey-white, convex, colonies on a blood agar plate after aerobic incubation for 24 hours. Short Gram-positive rods

32 Sample 24/2013. Dermabacter hominis 1. RapID CB Plus Dermabacter hominis (99%) Catalase + + +, + + +, + + +, + + -, + + +, + - -, +

33 Sample 24/2013. Primary culture on an anaerobic blood agar plate Growth on an anaerobic blood agar (FAA) plate after anaerobic incubation for 48 hours at +35 C. Matt, yellowish, convex colonies growing close to metronidazole and aminoglycoside disks. An aerobe or an anaerobe? The same or different bacterium than that growing on the aerobic plates? ->Aerotolerance tests! Gram-stanining!

34 Sample 24/2013. Aerotolerance test Aerobic growth on blood agar Growth on chocolated blood agar in 5% CO 2 Anaerobic growth on anaerobic blood agar (FAA) Upper part. (Subcultured from aerobic blood agar).this bacterium is aerobic, because it is growing only on the aerobic blood and chocolated blood agar plates. (Dermabacter hominis). Lower part. This bacterium is an obligate anaerobe because it is not growing on the aerobic plates. (Propionibacterium acnes)

35 Sample 24/2013 (8/2011) Propionibacterium acnes FAA Catalase + Gram-positive branching rods

36 Sample 8/2011. Propionibacterium acnes 1. RapID ANA II: Propionibacterium acnes (15 %). If indole positive -> P acnes (99%) - - -, - + -, - - +, - + +, + - +, This strain is indole negative. 2. Vitek 2 ANC Propionibacterium acnes

37 Keys of heaven in summer night (Red cambion, Silene dioica)