VCP - 2023

Siderotic PCs in Lab w PIMA

WNR channel graph from Dog 4, demonstrating an error in the automated gating of NRBCs. (A) Automated gating demonstrates a significant proportion of leukocytes counted as NRBCs (purple), while (B) demonstrates correct gating as leukocytes (turquoise) on the second run following dilution.

Unusual poorly defined cloud above & to the right of the nRBC cloud, extending into the basophil area. Also an abrupt delineation between the nRBC and leukocyte clouds, indicating errors in gating.

-Cases 10, 12: nRBC and leuko clouds abruptly delineated (gating error)

-Cases 8, 10, 12: signif merging of platelet/cell fragment cloud w the leuko cloud

PFA-200

Several patterns: (closure, non-closure, & flow obstr)

•Peaks – elevations above the plane of curve, rapid return to baseline (A, B, *)

•Valleys – dips below the plane of curve, rapid return to baseline (B, E, ^)

•Rapid initial increase – initial peak formed at >45° angle

•Slow initial increase – initial peak formed at <45° angle

•Steady decline – essentially linear, no change in slope, reaching baseline (B, C)

•Flatline – approximately horizontal after initial peak (D)

•Multiphasic – one or more signif changes to slope

•Initial vertical peak – rapid incr apparently to infinity in first seconds of flow (F)

Double Barr bodies and X-monosomy/X-trisomy mosaicism in a dog with presumed idiopathic epilepsy (some had 1, many had 0)

Nitro blue tetrazolium reduction test

Blue indicates activation (ROS in oxidative burst)

Border collie puppies with hematomas and RA, F8 gene:

Hemophilia A due to deletion, B is carrier, C is affected

All had prolonged aPPT, FVIII 5-6% activity

Lung mass ALP stain

Histiocytic sarcoma. Arrows = atypical round cells (ALP neg), arrowheads = respiratory epithelium (ALP pos)

Lung imprint, ALP stain

Mesothelial cells, ALP neg

3yo Golden w multiple cutaneous masses rapidly growing

CD3- Pax5- MUM1+

MUM1/IRF4 labeling in Langerhans cell histiocytosis, initial misdx as PCT

Cutaneous mass on flank of a dog

Keloidal fibroma

Unclear why aSMA+ in this case

BAL from a 9yo British shorthair, 3mo resp difficulty refractory to steroids & antimicrobials

Feline pulmonary Langerhans cell histiocytosis

Final: E-cad+/Iba-1+/CD1a+/CD5+/CD18+/MHCII+/CD204−/CD4−

Left to right: DI water, peritoneal effusion, CSF

Top low power, bottom oil immersion

Silica particles

Silica particles in urine, low-power and oil immersion.

Top row DI water, bottom row pleural effusion (low and high mag)

Barium particles

Both silica & barium. DI H₂O top, pleural effusion bottom; low mag left, oil immersion right.

It’s labeled so not much of a flashcard, but good pic

Effects on preservation:

SQ mass on thigh of 14yo Border Collie

Extracardiac adult rhabdoyoma

Desmin top, NSE bottom

SQ mass flank of 13yo mixed dog

Extracardiac adult rhabdomyoma

Desmin top, NSE bottom

8yo MN yorkie with respiratory effort, lethargy, mild pleural exudate, mediastinal mass

Spindle-cell thymoma colliding with a bronchogenic cyst

A) Well-diff’d pseudostrat ciliated resp epith, cyst lumen contains proteinaceous fluid, N0, histiocytes, RBCs.

B) Elsewhere, lining is attenuated and lined by squamous to stratified squamous epith.

C) In solid areas, neoplastic spindle to polygonal cells in streams/sheets w elongated to oval nuclei.

D) CK+

5yo Whiteface wether, WBC 708

B-cell leukemia

(A)Human spittle; (B) Flaky human hair; (C) Starch/glove powder; (D) Gram stain precipitate; (E) Medical lubricant; (F) Pleomorphic plant material

(G) Plant spore-filled spherule

(H) Fungal structure in a BAL from non-sterilized endoscope

(I) Fungal hyphae and conidial heads on a blood film left unstained for several months

(J) Diatoms from skin contamination in a urine wet-mount in a manatee

(K) Grain of pine pollen

(L) Plant hair/trichome

(M) Fragments of mosquito parts

(N) Booklouse trapped in immersion oil

(O) Superficial mixed bacterial on a blood film from a nail prick on a marmoset

(P) Oropharyngeal contaminants

(Q) Fragment of striated skeletal muscle

(R) Keratin flakes/bars

(S) Lipid in a blood film from a crested toad

(T) Endothelial cells in a blood film from a dog

(U) Glass shards on the edge of an FNA

Blood from a Zovawk pig

A: M0 and RBC

B: N0

C: E0

D : B0

Blood from a Zovawk pig

A: L0 and plts

B: M0

C: Plts (pleomorphic)

D : Plt

Blood from wild anurans

A: Intraerythrocytic haemogregarine

B: Lankesterella and a neutrophil

C: Intracytoplasmic structure and a thrombocyte

D: Hepatozoon sp. and a microfilaria

Blood from wild anurans

E: Trypanosoma sp.

F: Lankesterella sp.

G: Trypanosoma and Hemolivia sp.

H: Trypanosoma sp.

Bald eagle protein electrophoresis

Left AGE, right CZE

Paired serum + plasma

First 2 rows clinically normal

Last row clinically abnormal

- Note 2 defined gamma globulin fractions

AGE 1-6: prealb, alb, a1, a2, b, g

CZE 1-8: prealb, alb, a1, a2, b1, b2, g1, g2

Greyhound BM sample stored for 3d

Leishmania promastigotes

- (A) Procyclic promastigotes and amastigotes

- (B) Procyclic promastigotes

- (C, D) Elongated nectomonads (arrowheads) and leptomonad (arrow)

11yo FS Golden with SQ nodule, elevated liver enzymes

Needle tract seeding and malignant transformation of hepatocellular adenoma into well-differentiated hepatocellular carcinoma, SQ mass is at the core bx site

(A, B) HCA. Well-demarcated with adjacent normal liver, forms pseudolobular structures composed of regular thick trabeculae

(C) HCC. Effacing muscle & adipose, loss of lobar architecture, irregular thickness of trabeculae (>5 hepatocytes thick), moderate desmoplasia.

(D) Randomly distributed lytic necrosis & hemorrhage.

(E, F) Ki-67. Hepatic mass mild positivity (2.9 pos nuclei/HPF) vs intramuscular mass highly increased positivity (21.1/hpf)

BM from a horse with blepharitis and incidental hyperglobulinemia

Multiple myeloma with IgG(T) M-protein (IgG3 and 5)

Serum and plasma

Urine

Nasal mass in a 7yo Burmese

Olfactory neuroblastoma

(A) CK AE1/AE3, diffuse, strong membranous and cytoplasmic

(B) Vimentin, diffuse, strong membranous and cytoplasmic

(C) III beta-tubulin, diffuse, strong cytoplasmic

COX-2, diffuse, strong, 95% of cells, overlying resp epith & supportive stroma are negative

Lichtenstein’s green racer snake

Melanophoroma

4yo Aus cattle dog with lethargy and generalized pain, CSF

TNCC 348/uL, RBC 310/uL, TP 423 mg/dL

Mycobacterium haemophilum (leprae clade)

10yp DSH acute depression and anorexia, mod RA (16.3), severe leukopenia (1,200, N0 672), mild thrombocytopenia, FIV+, splenomegaly

Hemophagocytic syndrome in a cat with immune-mediated hemolytic anemia

6yo DSH 1wk lethargy, acute anorexia, marked NRA (9.7%), inappropriate rubricytosis (17), mod thrombocytopenia (59)

Spleen

BM

Mycoplasma haemofelis identified on PCR, secondary hemophagocytic syndrome

BM from a 9yo DSH with FIV+, panleukopenia (N0 0.27, L shift, toxic), HCT and plt WNL, splenomegaly

Presumptive hemophagocytic syndrome associated with co-infections with FIV, Toxoplasma gondii, and Candidatus mycoplasma haemominutum in an adult cat

Bone Marrow

A: highly cellular, granulo hyper, L shift, incr immatures

B: erythrophagocytosis

C: rubriphagocytosis

D-F: neutrophagocytosis

Spleen at splenectomy:

A-B: erythrophagocytosis

C: rubriphagocytosis

D-F: neutro and erythrophagocytosis

Post-mortem liver

Top: nodules, neutro and erythrophago

Bottom: hepatocytes w high N:C, indistinct borders, and degen N0 w cocci

Post-mortem BM:

(Later stage of dz)

A: Erythrophago

B: Eryth and neutrophago

C-D: Rubriphago

E-F: neutrophago

Mastocytemia and systemic mastocytosis in a dog

ProCyte Dx (A), Sysmex XT-2000iV DIFF (B), and WBC/BASO (C) scattergrams.

(A) A cloud was observed in the unusual location parallel and to the right of the monocyte dot plot location (red circle). Cells in that cloud were classified as either monocytes or neutrophils with no clear separation.

(B) Neutrophil and eosinophil dot plots were present at the respective locations (red circle) and appeared separated, but the instrument did not report numerical results for neutrophils and eosinophils. In addition to the normal lymphocyte dot plot location, the second cloud of cells classified as lymphocytes was displayed to the right of the monocyte dot plot area (blue circle).

(C) The second population of cells (above and to the right of the blue leukocyte cluster) is present (red circle), which was likely comprised of mast cells resistant to lysis in the basophil reagent. FSC indicates forward scatter; SSC indicates side scatter

Cutaneous hemangioma w MC in the blood channels:

10yo mixed dog with multifocal bone lesions after prior removal of ventral neck mass

Metastatic medullary thyroid carcinoma

CSF from a 6yo Jack Russel with episodic seizures, ataxia, and obtundation

•TNCC 635/uL (RI <5), TP 1.38 (RI <0.35), minimal RBC (10/uL, RI: 0)

Eosinophilic pleocytosis due to primary CNS histiocytic sarcoma

A: Well-demarc, unencapsulated, effacing WM

B: Iba-1

C: GFAP (normal tissue on R side is pos)

D: Numerous MNGC

E: Iba-1, membranous

F: GFAP+ astrocytes surrounded by neg neoplastic cells

Peritoneal effusion from an 8yo dachshund with HCT 5%, thrombocytopenia

Mycoplasma haemocanis

Initially had a duodenal ACA resected, received 2 blood transfusions, 2nd donor was known negative but nothing known about 1st

Blood smear:

2yo Golden with progressive paraparesis, intradural extramedullary mass L2

Nephroblastoma

WT1: multifocal nuc & cyto immunolabeling

Urine sediment from a 5yo Borzoi with erythema multiforme managed by pred

USG 1.011, pH 7.5, protein 3+, WBC 20-50 with clumps

Ddx Mcyoplasma or ureasplasma

Culture: Staph pseudointermedius, Mycoplasma spp, E. coli

DNA analysis: Mycoplasma canis

Conjunctival mass from 8yo mixed dog

Onchocerca lupi

2yo MN Terrier mix with ill-defined, soft, fluctuant mass R dorsal perineal area x 1wk. ~10cm, fluid-filled, non-painful, non-reducible

Initial concern carcinoma, but turned out it was, in fact reducible

Perineal hernia with entrapped fluid and reactive mesos

CSF from 2.5yo Boston Terrier with progressive tetraparesis, ataxia

MPS I (Hurler’s disease)

Deficiency of α-L-iduronidase

Recurrent inguinal mass in a 7yo FS Pug wtih fever, lethargy, inappetance

Ddx lymphatic neoplasm, lymphangiectasia, lymphocele, mild lymphocytic inflammation

NOT supportive of chyle or pseudochyle

Histo: Cutaneous lymphangioma, PROX-1 nuclear labeling

(A) SQ expanded by arborizing, empty vessels.

(B) Lined by single layer of uniform, flattened endothelial cells.

(C) Intracytoplasmic labeling for FVIIIra

(D) Intranuclear labeling for PROX-1

Later dev’d similar lesion near tarsus - poss lymphangiomatosis of the pelvic limb

8yo mixed dog, diffuse generalized thickening of the gastric wall

Signet ring gastric adenocarcinoma

17 wk English Bulldog with urinary incontinence, stranguria, hematuria

Grossly red-brown, turbid, USG 1.016, pH 7.5, mod proteinuria, 50+ RBC, 0-2 WBC, 5-9 epith

Malakoplakia, inclusions consistent with Michaelis-Gutmann bodies

PAS+ confirms macros

Alizarin red+ (calcium) with faint multifocal PB+ (iron)

Intracranial mass in 13yo Chihuahua w cluster seizures, CSF protein-cytologic dissociation (4 cells/uL, TP 47.6 mg/dL), mass in piriform lobe

Meningioma, meningothelial histomorphology

9yo Gordon Setter non-wt-bearing and swelling of 4th RF digit

Inflamed subungual keratoacanthoma

4yo DSH with swollen paws, mod NRA (0.20), hyperphosphatemia, mild azotemia

Metastatic mineralization due to CRF

18yo Hanoverian mare ovarian mass

Granulosa cell tumour

A) Strong, diffuse vimentin

B) Variable pancytokeratin

C) Moderate to strong, cytoplasmic inhibin-α

D) Moderate to strong, cytoplasmic, anti-Müllerian hormone

22yo QH gelding scraping from a corneal ulcer

Phaeohyphomycosis due to Cochliobolus sp. (anamorph Curvularia sp.)

9yo QH mare scraping from a corneal ulcer

Candida tropicalis

2mo F Bourbon red turkey poult from a backyard flock, submitted for necropsy. Several birds died in prev weeks, had yellow-coloured droppings, hunched w ruffled feathers, stopped eating. Impression from multifocal liver nodules.

Histomonas meleagridis

3mo F chicken found dead along w several others over prev weeks, no signs of illness. Postmortem tracheal swab.

Infectious laryngotracheitis caused by Gallid Herpesvirus-1

Syncytial cells w eos intranuc inclusion bodies in trachea, eyelid, & lung are diagnostic

Wild juvenile mourning dove with masses on the cere

Avipoxvirus, Bollinger bodies containing Borrel bodies

6yo M pet rabbit testicular mass

Granular cell tumour, ddx interstitial cell tumour

PAS:

A: PAS

B: Vimentin

C: Melan-A

D: CK AE1/AE3

Coelomic fluid in an Eastern River Cooter (Pseudemys concinna concinna)

Transudate with spermatozoa

Rectal scraping from a 14yo mixed dog with intermittent, recurrent large bowel diarrhea

Psyllium husk (tx’d w metronidazole, psyllium, fenbendazole)

ADVIA 2120 platelet absorption cytograms

A: Normocytic, normcohormic, B: microcytic, hypochromic RBCs causing high interference, see how gate is smaller than it should be for reticulated platelets (purple)

Gel column crossmatches

9yo Boston with severe leukocytosis (81,700)

Blood smear

Bone marrow

Paraneoplastic leukocytosis found secondary to GIST in duodenum

A: CD117 (KIT)+

B: Vimentin+

C: Desmin-

D: SMA-

Individuality examples

Left to right: High, low, intermediate

9wk F Irish Setter with progressive refractory seizures

CSF TNCC 1100/uL, TP 1939 mg/dL

Cerebral vascular hamartoma

MSA = muscle specific actin

•16yo FS DSH 0.5cm soft pink mass P3 of D4 RHL

Cyto ddx: neural or neurosecretory tumour (e.g. GCT), synovial sarcoma, HS, PCT, anaplastic carcinoma, pleomorphic MCT

Histo: presumptive pleomorphic MCT

IHC: Granular variant of a histiocytic tumour

A: Iba1

B: CD117 (staining MC)

C: Giemsa (in MC)

D: PAS (5% of T cells had stained grans, esp larger ones)

•TEM: Prominent filopodia or interdigitating plasma membranes, abundant ER, mod numbers of low-density membrane-bound granules w granular to fibrillar substance (few more electron-dense or w dense spherules, arrays, fragments)

12yo F Vietnamese Pot-Bellied Pig anorexia/lethargy x2d, open-mouth breathing, pale mm, liver nodules:

Blood smear:

Visceral MCT and mastocytemia, CD117+, CD3- CD79a-

Arrow is lipofuscin in hepatos

Urine sediment from an 11 mo dachshund w PU/PD, anorexia/lethargy, pyrexia

1.005, 2+ prot, 4+ blood, 0-5 RBCs, 4-8 WBCs

Leptospiral organisms

IHC for leptospira:

MAT:

2yo MN Creole Shepherd w chronic HL paraparesis and progressive neuro deficits

Suppurative spinal meningomyelitis in a dog with intra-neutrophilic cerebrospinal fluid cells Ehrlichia canis morulae

Blood cells in big-bellied searhorses