1. Cytological Examination: Part II
Clinical Pathology

2. Microscopic Evaluation
Scan at 10x
Determine if stained adequately
Any localized or increased cellular areas
Scan for any large objects: parasites, foreign bodies, etc.
Look at what type of cells are found
Examine at 40x
Evaluate individual cells
Examine at 100x (oil immersion)
Cell morphology, nucleus, chromatin, cytoplasm

3. Interpretation Inflammatory vs. Non-inflammatory
Most important judgement
May not get a definitive diagnosis, but may be able to get a general idea/general process.
Cytology may be helpful on what’s the next diagnostic step to take
Culture
Biopsy
Rads
Serology

4. Inflammatory cells found in Cytology
Neutrophils
May resemble same as blood neutrophils.
Be degenerative
Hypersegmented
Lymphocytes
Plasma cells
Active lymphocytes that have a very basophilic cytoplasm
Eosinophils
Mast cells- allergic inflammation
Macrophages
Large tissue monocytes.
Have abundant blue cytoplasm with vacoules that may contain phagocytized cells or debris
Oval to pleomorphic nucleus
Mesothelial cells
Cells that line the pleural, peritoneal,a nd visceral surfaces.
A type of macrophage

5. Neutrophils in Tissue

6. Lymphocytes and Plasma cells in tissue

7. Eosinophils in tissue

8. Mast cells in tissue

9. Macrophages in Tissue

10. Mesothelial Cells in Tissue

11. Classifications of Inflammation
Purulent
Pyogranulomatous
Granulomatous
Eosinophilic
May also be classified as duration:
Acute
Subacute
Chronic-active
Chronic

12. Purulent Inflammation (Abscess)
Most common type of inflammation
Usually caused by bacteria
Also called suppurative inflammation
Over 70% neutrophils with a few macrophages and lymphocytes

13. Pyogranulomatous inflammation
Also referred to as chronic/active
Consists of macrophages and 50-75% neutrophils

14. Granulomatous Inflammation
Greater than 50-70% of cells are mononuclear (monocytes, macrophage, giant cells).
Few neutrophils
Also called chronic inflammation.

15. Eosinophilic Inflammation
Consists of greater than 10% eosinophils
Allergic related
May see a few mast cells, plasma cells and lymphocytes

16. Selected Infectious agents of Cutaneous lesions
Bacterial agents
Tend to produce lesions characterized by >85% neutrophils, few macrophages, lymphocytes, and plasma cells.
Rods, cocci
Cytology is helpful in determining what kind of culture or stain is needed.
Fungal agents
Tend to have more macrophages than bacterial lesions, but may be mixed (pyogranulomatous). Low numbers of lymphocytes.
Sporothrix schenkii
Histoplasma capsulatum
Blastomyces dermatidis
Crytococcus neoformans
Coccidiodes immitis

17. Sporiotrichosis: Sporothrix schenkii
Organisms are round to oval or cigar shaped
Stain pale to medium-blue cytoplasm with a slightly eccentric pink or purple nucleus.
Dimorphic fungus found in the environment worldwide
Inoculated into tissue via puncture wounds
Suppurative to pyogranulamatous
Skin lesions are characterized by multiple, non-painful, nonpruritic nodules that may ulcerate and drain purulent exudate.
Dissemination is rare

18. Sporotricosis continued
Diagnose via cytology, biopsy, fungal culture
Easier to diagnose in cats, tend to have more organisms
Infected cats are highly contagious to humans
Treatment includes long term antifungals
Ketoconazole
Itraconazole
Prognosis is fair to good, but relapse is possible.

21. Histoplasma Capuslatum
Round to oval- yeast-like
Dark blue/purple staining nucleus surrounded by a thin halo
Causes systemic disease
Cutanous lesions are rare, causes lungs or GI tract infections
Most common in termperate and subtropical areas.
Diagnosed through cytology, histopathology, fungal cultures, rads

23. Blastomyces dermatidis: Blatomycosis
Caused by inhaling the conidia
Causes a disseminated infection
Lymph nodes
Skin
Bones
Other organs
Found in mostly acidic soils
Diagnosed by cytology, histopathology, serology and fungal cultures.
Most are single, blue, spherical and thick walled.
Pyogranulamatous

25. Cyptococcus Neoformans: Cryptococcosis
Found worldwide
Organism is inhaled and establishes infections in the nasal cavity, sinuses, skin and other organs
Spherical, yeast-like organisms
Thick, clear mucoid capsule
May be budding or non-budding
Cats: URI signs, SQ swelling over bridge of nose, non-painful, may have CNS signs
Dogs: CNS signs and ophthalmic signs usually occur. Nodules on lips and nose.

28. Coicidiodes Immitis: Coccidiomycosis
Dimorphic fungus and soil saprophyte endemic to desert areas
Organisms are inhaled and disseminate in body
Skin lesions are nodular, abscesses and draining tracts
Painful lameness

29. Coccidiomycosis Continued
Spherical with thick deeply stained wall.
Diagnosis thought cytology, pyogranulamatous, histopathology, serology and fungal culture.
Treated by long term systemic antifungals (8-12 months)
Prognosis is unpredictable
Relapses are common
Fungal cultures are contagious
Infected animals are not considered contagious

30. Leishmania donovani: Leishamaniasis
Protozoa transmitted by blood-sucking sandflies
Endemic to Central and South America
Sporadic infections in the US
A visceral and cutaneous disease that develops over months-years
Lesions are dark and small to large and ulcerated.
Diagnose by imprints, scraping and FNA
Organism usually found in macrophages
Small, round to oval
Has a very light blue cytoplasm, an oval nucleus, and a small dark kinetoplast
Usually numerous organisms found
Not curable
Contagious to other dogs through vector

32. Non-inflammatory Lesions
Neoplastic
Epithelial
Mesenchymal (spindle cell)
Discrete Round cell tumor
Non-Neoplastic
Cysts (sebaceous)
Hyperplasia (prostatic hyperplasia)
Dysplasia
Hematomas
Seromas
Salivary Mucocele

33. Epithelial Neoplasms Tend to exfoliate cells in sheets or clumps
Cells tend to be large with moderate to abundant cytoplasm
Benign epithelial tumors
Papilloma
Epidermal inclusion cyst (epithelioma)
Perianal gland adenomas
Malignant epithelial tumors
Perianal gland adenocarcinoma
Squamous cell carcinoma

35. Mesenchymal tumors: Spindle cell tumors
Tend to exfoliate individual cells instead of clusters
May be difficult to differentiate from normal granulation tissue (spindle cells are plump).
Difficult to differentiate from the different types of tumors on cytology.
Benign forms:
Fibromas
Lipomas
Hemangioma
Malignant forms:
Fibrosarcoma
Liposarcoma
Hemangiosarcoma

37. Discrete Round Cell Tumors
Tend to exfoliate small to medium sized cells.
Also called cutaneous round cell tumors
Types:
Mast cell tumors
Cutaneous lymphosarcoma
Histioctyomas Transmissable venereal tumor

40. Evaluation of Malignant Potential (Criteria of Malignancy)
Variation of cell size
Variation in nuclear size
Multinucleated
Increased nucleus: cytoplams ratio
Mitotic figures
Variation in nucleolar size/shape
Coarse Chromatin pattern
If more than 3 criteria are recognized in a high percentage of cells, this is strong evidenc for malignancy
If 1-3 criteria are present, may be either benign or malignant and should be sent to pathologist or biopsied.

41. Submission of Cytologic Slides
Send 2-3 air-dried unfixed smears and 2-3 stained smears
Fluid samples should have smears prepared from them immediately
Also send EDTA and red top tubes filled with fluid
Mail in protective containers
Timely transportation service
Easy accesible and easy to collect cytology
Tranquilization/anesthesia seldome needed for sample collection
Quick-sample can be prepared, stained, and microscopically evaluated in minutes.