Clinical History

A consise history is essential for the best diagnostic cytology report.

General

Specimens should be prepared on frosted-end slides and labeled with pencil (ink from pens or felt-tip markers wash of during processing). Slides that have been stained and examined in the hospital may be included.

Unstained specimens or cytological examination must be kept from exposure to formalin or formalin fumes (proper staining will not occur on formalin exposed smears). Package cytology and biopsy samples in separate bags to prevent exposure to formalin fumes.

Provide all patient information required on the Test Request Form.

Direct Smears

Air-dried smears should be submitted. Each slide should be labeled with pencil on frosted-end slides (ink from pens or felt-tip markers wash of during processing).

Aspirated material should be transferred to slides and spread by squash technique or as in preparing a blood film. Do not submit syringes with needles.

Fluids

Submit all fluids in lavender top tubes to preserve cellular morphology and prevent clotting (do not submit fluids in red top tubes). It is helpful, but not a requirement, to submit 2 freshly made smears, labeled and prepared as described above. Submit separate Test Request Forms for each sample from multiple sites.

All fluids submitted will be processed for fluid analysis in addition to cytological examination. Total protein concentration and cell counts are used to classify effusions into categories that indicate underlying disease pathogenesis.

Special Chemical analysis on fluids—the diagnostic specificity of effusions can often be enhanced by assay of additional analytes, particularly in exudative effusions.

Below are several examples:

1. Suspect uroperitoneum—elevated creatinine and potassium in effusion
2. Suspect bile peritonitis—elevated bilirubin in effusion
3. Suspect chylous effusion—Triglyceride levles in effusion higher than in serum or Cholesterol/Triglyceride ratio <1
4. Suspect FIP—Protein electrophoresis, FIP PCR
5. Suspect pancreatitis—elevated amylase in effusion supports diagnosis

CSF

CSF should be collected into lavender top tubes. For optimal cell preservation it is recommended that 2–3 drops of the patient's serum or bovine serum albumin be added to one of the submitted lavender top tubes. IT IS IMPERATIVE TO LABEL THE TUBE: CSF WITH SERUM/ALBUMIN ADDED. The remainder of the CSF should be submitted in a second lavender top tube.

Bone Marrow

A CBC should be perormed in conjunction with bone marrow cytology. Examination of core biopsies along with marrow smears will provide the most complete assessment of hematopoiesis. Be sure to package core sample and aspirate smears separately to avoid exposing slides to formalin fumes.

Buffy Coat

Bufy coat smears are useful for concentrating WBCs for examination. Detection of hemoparasites, viral inclusions and circulating mast cells are common indications for buffy coat examination.