Microbiology Lab Lecture 1

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1) Mycobacterium TB

§ Solid medium (Lowenstein-jensen medium ''LJ")

§ It Selective & enriched medium containing egg, protein and malachite green → inhibit growth of normal flora

§ 6-8 week for growth.

§ Liquid medium is faster (3-4 week)

§ Pigment is dry & golden.

2) Sputum of TB

§ On Ziehl-Neelsen (ZN) stain.

§ Red bacilli → +ve

§ Mycobacterium TB pneumonia

3) Immunoflurecence Test

§ Labile antibody

§ Faster identification

4) Tuberculin test (mountox test)

§ Depend on delayed type hypersensitivity.

§ +ve → vaccinated or infected patient.

5) Sever case of TB (x-ray)

§ Pneumonia

§ Typical pneumonia

6) Leprosy (by mycobacterium leprosy)

§ Lepromatous leprosy (more sever case)

§ Lion face

§ Break of bone of nose

§ Increase thickness of skin

7) Leprosy (Skin lesion)

§ Loss of sensation

§ Less than 5 in whole body

8) Leprosy

§ Infection increase by loss of sensation.

9) Conjuctivitis

§ By Chlamydia Trachomatis serotype D-K

10) Trachoma

§ By Chlamydia Trachomatis serotype A-C

11) Urethritis

§ By Chlamydia Trachomatis serotype D-K

Case :

A Thai construction-site worker diagnosed as having HIV 3 years previously was found unconscious and admitted to the intensive care unit. A chest X-ray taken on admission is shown in (A). Gram stain on a sputum specimen collected from the patient at admission was non-contributory. A further specimen was obtained and a Ziehl-Neelsen stain performed, the result of which is shown in (B).

a. What respiratory infection does he have?

b. What does the Ziehl-Neelsen stain demonstrate?

c. Does he represent an infection hazard to other patients or staff in the ICU, and if so why?

d. Does his geographical origin suggest any specific issues regarding choice of antimicrobial therapy?

a) typical pneumonia.

b) Acid fast bacilli

c) Yes, because ICU patients may infected because they have low immunity → Isolation

d) Yes, because its tolerated (more resistance to antibiotics)

A) Pneumonia

B) Ziehl-Neelsen (Mycobacterium TB)

7

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