1. Diagnostic Microbiology and Immunology
Chapter 31
Diagnostic Microbiology and Immunology

2. Lab Diagnostic Time Lines

3. The Swab
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4. Here’s Some, Depending on Specimen
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5. Urine Analysis Dip Sticks
Top: After reaction with metabolites in urine.
Bottom: Before reaction with metabolites in urine
Test time = 60 sec.
Measures: glucose, bilirubin, ketones, sp. gravity, pH, protein, urobilinogen, nitrite, esterases. Top two right are false positives to show the color reaction.

6. Eosin Methylene Blue Agar

7. There are hundreds of Selective and Differential Bacteriological Media
Text goes on describing particular samples: wounds, feces, genital swabs, etc. We will cover those when we get to specific diseases.

8. Urethral Swab: Microscopy + Plating on Thayer-Martin Agar
Oxidase Test Reagent poured onto the agar AFTER the colonies grew up.

9. Gas Pack, Anaerobic Chamber

10. Some Clinical Tests

11. Metabolic Reactions The Classic API-20e
Glucose Phenol Red with Durham tube.
TSI: triple sugar iron agar.
Citrate Test

12. More Clinical Tests

13. Testing Antibiotic Sensitivity
Kirby-Bauer Zone of Inhibition
E-test.
MIC: Minimal Inhibitory Concentration

14. Some Antibiotics – Interpretation of Size of the Zone of Inhibition

15. Pseudomonas aeruginosa MICs
Each numbered row – one antibiotic, highest conc at left, lowest at right.
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16. E test
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17. Working in a BSL-4 Lab
The Gen Micro Labs in AHC2 are BSL-1, most our research labs are BSL-2.
BSL-3 labs: to contain pathogens that could be infective as an aerosol.
BSL-1: lab people wear lab coats, gloves..and usually does not involve pathogens.
BSL-2: needs to contain pathogens in hoods, etc. Aerosol generating equipment must be in a biosafety cabinet.

18. Disease Progression: Untreated Typhoid Fever
Antibody Titers: Generally done by serial 1:2 dilutions from a blood sample. Highest dilution that brings about an Ab-Ag reaction.
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19. Disease Progression: Untreated Typhoid Fever
Antibody Titers: Generally done by serial 1:2 dilutions from a blood sample. Highest dilution that brings about an Ab-Ag reaction.
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21. Monoclonal Antibodies

26. Precipitin Reaction

27. Precipitin Rxns on a Glass Slide
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28. Agglutination Reactions

29. Latex Bead Agglutination for S. aureus

30. Fluorescent Antibodies
Clostridium septicum stained with FITC-Ab,
C. chauvoel stained with Rhodamine-Ab

31. Direct and Sandwich (Indirect)

32. Yellow-Green cells are CD8 Cells Red-orange cells are CD-4 Cells
B and T Cells…
Yellow-Green cells are CD8 Cells Red-orange cells are CD-4 Cells

33. Cell Sorting
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34. Enzyme Immuno-Assays

35. EIA Kits for Small Clinics

36. Immunoblots: Detecting Blotted Proteins (after electrophoresis)

37. Nucleic Acid Diagnostics

38. PCR Detecting Mycobacteium tuberculosis
Lanes Molecular Weight Standards
Lanes 2-12 from different TB patients sputum
Lanes from non-TB patients with lung symptoms.
Lane 15 – from known Mycobacterium tuberculosis DNA.