Sputum for fungi

What sample is needed for Sputum for fungi?

1. The sputum sample is needed to find the presence of the fungus.
2. Advise patient to get deep cough sputum.
3. The sample can be refrigerated for up to 24 hours.
4. Sputum may be stable at room temperature for 72 hours.
5. Do not freeze the sample.
6. Store it at room temperature.

What are the precautions for Sputum fungi?

1. Sputum should be examined as fresh as possible because Histoplasma capsulatum dies rapidly at room temperature.
2. Saprophytic fungi, such as candida and commensal bacteria, rapidly multiply if kept at room temperature, interfering with the separation of pathogenic fungi.
3. Try to minimize contamination with the saliva.
4. Stop aspirin, ibuprofen, naproxen, and warfarin, which will thin the bronchial secretion.

How will you collect a good sample of Sputum for fungi?

1. Brush your teeth and rinse your mouth (don’t use antiseptic mouthwash).
2. Take a couple of long, deep breaths.
3. Breathe in deeply again and cough hard until sputum comes up.
4. Spit out the sputum into the sample cup.
5. Keep coughing up sputum until there is approximately 1 teaspoon.

What are the indications for Sputum for fungi?

1. This is done to diagnose respiratory fungal infection.
2. In the case of :
   1. shortness of breath
   2. fever
   3. A  cough that is, most of the time, dry.
   4. Muscle aches and pains.

How will you discuss the microbiology of Fungi?

1. Fungi are microorganisms. The majority are nonpathogenic.
2. Deep fungi or systemic fungi are characterized by the involvement of the visceral organs or are penetrating types of infection.
3. Actinomycetes and Nocardia are bacteria that cause infections resembling fungal infections.
4. What are the common types of fungi?
5. Dimorphic fungi:
   1. Blastomyces dermatidis (Blastomycosis).
   2. Coccidioides immitis  (Coccidioidomycosis).
   3. Cryptococcus neoformans (Cryptococcosis).
   4. Histoplasma capsulatum (Histoplasmosis).
   5. Sporothrix schenkii (Sporotrichosis).
6. Candida albicans.
7. Candida tropicalis.
8. Aspergillus fumigatus.
9. Aspergillus flavus.

Fungi are eukaryotic organisms and are divided broadly into three main groups:

What are the Yeasts?

1. These are single-celled. These are facultative anaerobes.
2. Candida e.g. C.albicans
3. Cryptococcus, e.g., C. neoformans.
4. Torulopsis.
5. Trichosporum.
6. Malassezia.
7. Rhodotorula.

What are the Molds?

1. These are filamentous fungi (hyphae). These are aerobic.
   1. These fungal hyphae form mycelium.
   2. Mycelium has two functions:
      1. The vegetative mycelium penetrates into the medium and absorbs nutrients.
      2. Aerial mycelium has reproductive structures for the spread of molds.

What are the Dimorphic fungi?

1. This exists in both the above forms.
2. 1. Blastomyces dermatidis, causing North American blastomycosis.
   2. Histoplasma capsulatum, causing Histoplasmosis.
   3. Histoplasma duboisii, causing African histoplasmosis.
   4. Sporothrix schenckii, causing Sporotrichosis.
3. Some of the fungi that exist in either form are called dimorphic fungi.
4. The cell wall of the fungi is thick and composed of polysaccharides.
5. Fungi are not motile.

What are the factors leading to fungal infections?

1. Most of these fungal diseases are opportunistic and need some predisposing factor leading to Mycosis.
2. Predisposing factors are:
   1. Cancers.
   2. Radiation.
   3. Chemotherapy.
   4. Antibiotics.
   5. Immune deficiency syndrome.
3. A sputum fungal smear is one of the best ways to determine whether your respiratory illness is caused by fungus.
   1. A positive smear for fungus indicates a fungal infection.

What are the fungal infections seen in the respiratory system?

1. The following types of fungal infections may be seen in the respiratory system:
   1. Aspergillosis.
   2. Blastomycosis.
   3. Coccidioidomycosis.
   4. Histoplasmosis.
   5. Cryptococcus.
   6. Pneumocystis carinii.

What is the normal for Sputum fungi?

• A normal (negative) result means no fungus was seen in the test sample.

Abnormal Results

• When sputum is positive for fungal infection.

What is the procedure for Sputum fungi identification?

1. The smear can be stained.
2. Wet preparation:
   1. Take skin scraping, hair, nail clipping, vaginal swab, sputum, or body fluids.
   2. Make a thin sputum smear and mix it with KOH (10%).
   3. Then, the smear is examined under the microscope.
   4. Advantages of wet preparation:
      1. Same day result.
      2. In some cases, accurate diagnosis.
   5. Disadvantages:
      1. Good with the expert person.
      2. False positive and false negative cases are seen.
3.  Gram stain (invented by Hans Christian Gram).
   1. Make a sputum smear on the slide.
   2. Fix it with heat.
   3. Stain with Gram’s stain.
   4. See under the microscope.
4. Wright stain or Giemsa:
   1. It is used for histoplasmosis.
5. Papincolaou stain:
   1. It can be used like gram stain and has the same advantages and disadvantages.
6. Indian ink or nigrosin:
   1. This preparation is used for Cryptococcus.
7. Tissue biopsy:
   1. Tissue biopsy may be stained with PAS (periodic acid-Schiff) or methenamine silver stain.
   2. It is dependent upon the number of organisms present in the biopsy tissue.
8. Culture:
   1. It is done on the Saubourads dextrose agar medium (SDAM).
   2. It gives a definite diagnosis.
   3. It depends upon the number of organisms present in the culture specimen.
   4. It also depends upon the specific media used for the culture.
   5. Candida albicans show raised creamy smooth colonies after 72 hours on SDAM.
   6. Another media used is nutrient agar media.
      1. Fungi grow slowly, and it may take several weeks to grow fungi.
   7. C. neoformans form white, granular, or wrinkled first and later on moist, shiny, and mucoid colonies on SDAM.
9. Serology:
   1. It may be helpful in some fungal infections like histoplasmosis, coccidioidomycosis, and South American blastomycosis.
   2. Two samples are needed: one to find the cause of fungal disease and one to repeat for rising titer after 1 to 2 weeks.
   3. So, the confirmation is delayed for 2 to 3 weeks.
   4. There may be a false negative result or false positive results, and nondiagnostic results as well.
10. Skin test:
    1. The advantage is the results in 24 to 48 hours.
    2. The disadvantage is that antibodies need time to develop.