Microbiology (lab diagnosis result of fungal and bacterial skin infections)

1. By :
Osama Al-Zahrani
@OSAMA_Z96

3. * Sample :
1- Skin infection :
Skin scraping for fungi.
2- Nails infection :
Nail scraping for fungi.
3- Hairs infection :
Infected hair for fungi.
* Test :
1- Direct microscopy by KOH Preparation :
- 10% for skin scraping.
- 20% for nails scraping.
- Fungal elements are seen (Hyphe & spore).
2- Culture :
Growth of mycelia.

4. * Test :
Microscopy KOH preparation for fungi.
* Result :
Fungal elements are seen (Hyphe & spore).

5. Hyphae
Spore
MicrosporumEpidermophyton Trichophyton
Morphology of fungal elements under microscope

7. * Test :
Skin KOH preparation for fungai.
* Result :
Fungal elements are seen (Hyphe & spore).
* Diagnosis :
Tinea corporis (Body infection).

9. * Test :
Skin KOH preparation for fungai.
* Result :
Fungal elements are seen (Hyphe & spore).
* Diagnosis :
Tinea pedis (athlete’s foot).

11. * Test :
Nail KOH preparation for fungai.
* Result :
Fungal elements are seen (Hyphe & spore).
* Diagnosis :
Tinea unguium (Tinea of nail).

13. * Test :
Hair KOH preparation for fungai.
* Result :
Fungal elements are seen (Hyphe & spore).
* Diagnosis :
Tinea capitis (Scalp ringworm).

15. * Sample :
- For staphylococcus aureus & streptococcus pyogens :
1- Fluid.
2- Pus.
- For mycobacterium leprae :
1- Nasal scrapings.
2- Biopsies of skin lesions.
* Test :
1- Gram stain.
2- Culture on blood agar.
3- Antibiotic Sensitivity test.

16. Folliculitis Abscess

17. * Test :
Gram stain.
* Result :
Gram positive cocci in clusters.
* Diagnosis :
Staphylococcus aureus.

18. * Test :
Culture in blood agar.
* Result :
Growth in blood agar.
* Diagnosis :
Staphylococcus aureus.

19. * Test :
Culture in Mannitol salt agar.
* Result :
Yellow colour due to fermentation of mannitol.
* Diagnosis :
Staphylococcus aureus.

20. Used to diagnose Staphylococcus aureus

21. Impetigo

22. * Test :
Gram stain.
* Result :
Gram positive cocci arrange in chains.
* Diagnosis :
Streptococcus pyogenes.

23. * Test :
Culture in blood agar.
* Result :
Haemolyse blood.
* Diagnosis :
Streptococcus pyogenes.

24. * Test :
Antibiotic sensitivity test.
* Result :
Bacitracin sensitive.

25. Used for identification of group A hemolytic streptococci

26. Tuberculoid leprosyLepromatous leprosy

27. * Test :
Acid-fast stain (Ziehl–Neelsen).
* Result :
Acid fast bacilli of Mycobacterium leprae.
* Diagnosis :
Lepromatous leprosy.

28. Test used to diagnose Mycobacterium tuberculosis & Mycobacterium leprae

29. Test used to diagnose Mycobacterium leprae