Specimen collection and waste management

Prepared bySamira fattah

Assis. Lec.College of health sciences-HMU

Lab. 4

Specimen collection

Why specimen collection is Important in Microbiology

Specimen collection and transportation are critical considerations , because any results the laboratory generates is limited by the quality of the specimen and its condition on arrival in the laboratory.

Specimens should be obtained properly to minimize the possibility of introducing contaminating microorganisms that are not involved in the infectious process.

Containers and swab for the collection of specimens:

Containers:

For faeces:-• Universal container• Spoon attached to the inside of the screw cap

For urine:-• Universal container for small quantities• For larger quantities 250 ml wide

mouthed screw-capped bottles are convenient

For sputum:-• Universal container should

not be used• wide-mouthed disposable containers should be used

For blood:-• Without anticoagulant for serological examination• With EDTA for parasitological examination

BLOOD CULTURE BOTTLE:• This must be at least large

enough to hold 50ml of liquid medium ,with which it is issued from laboratory ,plus 5-10ml of patient’s blood

Syringe and needle for aspiration.

• Wound pus• CSF• Pleural effusion• Amniotic fluid• Synovial fluid

Swabs:-Swabs suitable for taking Specimensof exudates from the throat, nose, ear , skin, wounds and other accessibleLesions.it consist of a sterile pledget of absorbent material, usually cotton-wool or synthetic fiber, mounted on a thin wire of stick

Swabs for special purpose: Baby swabs Pernasal swabs Post-nasal swabs Laryngeal swabs High vaginal and cervical swabs

Specimen collection guidelines

• Time of collection 1. During the acute phase 2. Before antimicrobial therapy 3. Time of the day (1st morning)

• Contamination – Normal flora

• Specimen containers• Sterile, leak proof

Labeling Specimen

• Each sample must have a label attached to the specimen container bearing the following information:

• Patient name• Type of specimen.• Collection date and time.• Test requested.• Name of ordering physician.

Specimen transport• Many microorganisms are susceptible to environmental

conditions, thus use of special preservative or holding media for transport of specimens delay for more than 2hr. is important to ensure organism viability. – Keep organism viable not encourage growth(Nonnutritive) – Examples

• Stuart’s medium • Cary – Blair medium

• Specimens should be in tightly sealed and transported in sealable, leak-proof plastic bags.

• Specimen Transport Bag

Specimen rejection criteria• Unlabeled or improperly labeled specimen• Mismatch information • Improper container(nonsteril) or medium(anaerobic bacteria in aerobic

medium)• Improper temperature• Insufficient specimen quantity• Leaking container • Dried out swab• Late specimen( more than 2hr. not preserved)

Physician must be informed about rejection

Waste management

Microbiological waste includes

- Contaminated Sharps:• syringes with/without Needles• slides• slide covers • specimen tubes - Contaminated Solids:• culture dishes• flasks • Petri dishes• gloves, gowns, masks,

- Liquid• Liquid growth media. • Human body fluids: -Blood and its components -Cerebrospinal and synovial fluid -Semen fluid -Vaginal secretions

Disposal methods

• Incineration Controlled incineration at high temperatures (over 1000°C) is one of the few technologies with which all types of health-care waste

can be treated properly and it has the advantage of significantly reducing the volume and weight of the wastes treated.

Disposal methods

• Chemical disinfection

o Chemicals are added to the wastes to kill or inhibit pathogens.

o This type of treatment is suitable mainly for treating liquid infectious wastes such as blood, urine, feces or hospital sewage.

o Typically, a 1% bleach (sodium hypochlorite) solution or a diluted active chlorine solution (0.5%) is used.

Disposal methods

• Autoclaving

Autoclaving is environmentally safe but in most cases it requires electricity, which is why in some regions it is not always suitable for treating wastes.

Disposal methods

• Needle extraction or destruction

o Some appliances run on electricity (destroying the needles by melting). But cannot be used widely particularly in remote areas.

o Needles can also be removed from syringes immediately after the injection by means of small manually operated devices. The needles are then discarded into the sharps pit.

Disposal methods

• Shredderso Shredders cut the waste into small pieces.

o They are often built into closed chemical or thermal disinfection systems.

o Shredding, which in certain circumstances provides a means of recycling plastics and needles, should be considered whenever needles and syringes are available in large quantities.

Disposal methods

• Encapsulationo Encapsulation (or solidification) involves filling containers with

waste(sharps, chemical or pharmaceutical residues, or incinerator ash) adding an immobilizing material(such as plastic foam, bituminous sand, lime, cement mortar, or clay ),once the medium has dried, the containers are sealed and disposed of in a sanitary landfill or waste burial pit.

o The purpose of the treatment is to prevent humans and the environment from any risk of contact.

Waste Containers • Containers must be: -appropriate for the contents -not leak -be properly labeled and -maintain their integrity if chemical or thermal treatment is

used.

• Containers of biohazardous material should be kept closed.

Waste Containers

• Contaminated Sharps

Waste Containers

• Contaminated Solids

Waste Containers

• Contaminated liquid Liquids should be placed in borosilicate

or polypropylene containers for

autoclaving.

Waste Containers

• Human tissues

They are usually red, and are labeled with the biohazard symbol and the words Pathological Waste.

Waste Containers

• Biohazard bagsBiohazard Bags have the biohazard symbol printed on them as well as usage instructions

for proper handling and personnel safety.

LABORATORY EXERCISETask: Take the tonsillar swab and cultivate the obtained specimen. -Method: A pair of students will take the tonsillar swab from one another by using a cotton swab.

1. Sign your name on the bottom of the Petri dish with blood agar .2. Wipe off the obtained swab on the surface of the blood and make the inoculum . The used swab

will be then put into the beaker with the disinfectant on the table.3. Incubate the inoculated plate at 37oC for 24 hours and put plates "upside down" to prevent

condensation of water on the surface of the agar.4. In the next laboratory you will read the results of your bacteriological culture and describe

observed bacterial colonies .