Cytology Processing For District Laboratories

Justification for Processing:

1. All unfixed Cytology cell samples will begin to degenerate from the moment of collection, rendering them difficult to interpret and potentially unsuitable for diagnostic purposes. 

2. If a specimen cannot be sent to HQE immediately, it must be PROCESSED INTO SMEARS to avoid degenerative cell changes. 

3. Specimens with high mucus content, such as sputum, bronchial aspirates, or mucocele fluid, may be preserved for 12 to 24 hours, if refrigerated at 2-8°C.

4. Specimens with high protein content, such as pleural, peritoneal, or pericardial fluids, may be preserved for 24 to 48 hours if refrigerated at 2-8°C.

5. Specimens with low mucus or protein content, such as urine or cerebrospinal fluid, may endure only a 1 to 2-hour delay, even if refrigerated.

6. For Non-Gynae (NG) specimens, please record the appearance of the fluid and slides prepared on the Non-gynaecology worksheet. 

7. For FNAC sample taken at district lab, please record relevant clinical examination and procedure details on the Fine Needle Aspiration Worksheet.

Sample Preparation Techniques:

1. Direct Smear: For limited (less than 1 mL) or mucoid samples (such as sputum or pus), put sample directly onto slides, make a direct smear. For cerebrospinal fluid, please refer to Cytology Processing Schedule (Number 8).

2. Centrifugation: For samples such as body fluids in 5mL to 50 mL volumes, spin sample in centrifuge for 2000 rpm/ 5 minutes (Note: Centrifuge settings differ according to model). Retrieve sediment onto slide and make smear by using Pick and smear technique. Send any remaining sample to Cytology Laboratory for Cell Block preparation if necessary.

3. Sedimentation: This method is for protein-rich body fluids received in large volumes (more than 50 mL), usually pleural or peritoneal fluid. Sedimentation can be done for a period of 3 to 4 hours by leaving sample in a beaker. The supernatant is disposed while sediment can be processed in smears by using direct smear technique.

4. Fixation (according to type of specimen):

   1. Wet fixed smears: Immerse smear immediately while still wet in 95% ethanol for 30 minutes. Do not allow smear to dry up before fixation.

   2. Dry fixed smears: Air dry the smeared slide.

   3. Please label slides with Patient Name, Lab No, Site of procedure and type of fixation (Dry / wet).

5. Processing technique depends on type of specimen. Please refer to the Cytology Processing Schedule below.