Cytology specimen collection and handling (Sputum specimen) in histology lab

There are many types of specimens for cytological examination. Cytology specimen collection and handling are very sensitive. Each sample has its own standard operating procedure. But some steps are common in all.  We need these things

 

 

• Fixatives
• Container or jar – Coplin jar made of glass or plastic is used as a fixative container.
• Request form

How to fix the specimen in the cytology

There are two types of smears used in cytology, depending on the staining method. 

• Wet Smear
• Air-dried smear

A wet sear is preferred to air-dried smear.

A wet smear is prepared by instantly fixing the slide before it dries. There are three types of fixatives in cytology. 

1. An equal part of ether with 95% ethyl alcohol
2. Formol alcohol
3. 95% ethyl alcohol

Papanicolaou’s and H and E stains are used on wet-fixed smears.

Note: Fifteens are sufficient for specimen fixation. Slides may remain in the fixative for up to 15 days without deterioration.

Air-dried smear prepared by simply allowing it to air-dry. Giemsa stain, Diff quick, and Leishman stain are used.

Request form of cytology specimen

The request form must contain the following information about the patient.

• Patient name, gender, age
• Specimen site
• Clinical detail
• Method of fixation (wet or air dry)
• In the case of the cervical specimen, there should be a date of the menstrual period, and hormone therapy.
• Previous History

Sputum specimen collection guidelines-Respiratory Tract

We collect three types of samples from the respiratory tract.  

• Sputum
• Bronchial Aspirate, washing, brushing
• Bronchoalveolar lavage

A fresh, early morning specimen should be collected by the deep cough. The sample should transfer to the laboratory immediately. Sputum process by wet fixation technique.

Note: If it is not possible to transport the specimen, then the sample should be pre-fixed by asking the patient to expectorate into a wide-mouth small jar filled with 70% ethyl alcohol.

Bronchial specimen collected during bronchoscopy. Centrifuged and smear prepared from the cell bottom. It is fixed in 95% ethyl alcohol. Direct smear can be prepared from bronchial brushing. 

Bronchoalveolar lavage: It involves the infusion and aspiration of a sterile saline solution into the air passages. This fluid should be sent to the lab as possible. If delay in transporting, an equal amount of 95% ethyl alcohol should be added to that fluid.