Pathology of the Hematopoietic System GROSS/HISTO LAB

Transcription

1 Pathology of the Hematopoietic System GROSS/HISTO LAB Paul Hanna (thanks to Dr s Aburto, Martinson & Fenton) Fall 2014

2 Slide 1 Spleen from a Beaver Give a morphologic diagnosis and possible etiology & name of disease

3 Slide 1 Spleen from a Beaver 1) Splenitis, suppurative (necrosuppurative), multifocal, acute, severe 2) Fracisella tularensis / Tularemia Yersina pseudotuberculosis / Yersiniosis

4 Slide 2 Canine parathyroid glands (note thyroids are normal size). Give a morphologic diagnosis and give two possible causes.

5 Slide 2 Canine parathyroid glands (note thyroids are normal size). Note, all 4 parathyroid glands are symmetrically enlarged 1) Diffuse parathyroid gland hyperplasia 2A) Renal secondary hyperparathyroidism (hyperphosphatemia and impaired activation of Vit D 3 ) 2B) Nutritional secondary hyperparathyroidism (excess dietary phosphorous & low Ca/Vit D 3 )

6 Case #1 History: 8 year old beagle Neck pain for the past couple of weeks Paresis, followed by paralysis developed over the past few days

7 Gross Description courtesy of Dr L Pack, AVC

8 Gross Description A nodular mass is present within the second cervical vertebrae. It protrudes into the spinal canal (compressing the spinal cord at this site) courtesy of Dr L Pack, AVC

9 Gross Description

10 Gross Description On section, a soft tan to pink gelatinous mass is present within the marrow cavity of the vertebral body with slight dorsal protrusion into the spinal canal.

11 Differential Diagnoses:

12 Differential Diagnoses: Multiple myeloma, osteosarcoma, osteomyelitis

13 Histology

14 Histologic Description:

15 Histologic Description: There is a marked increase in the cellularity of the bone marrow (100% cells / 0% adipose tissue)

16 Histologic Description: Sheets of tightly packed neoplastic round cells infiltrate the marrow cavity of the vertebral body

17 Histologic Description: The cells are round with distinct cell margins and a moderate amount of pale basophilic cytoplasm occasionally with perinuclear clearing. The nuclei are eccentric and round with coarse clumped hyperchromatic chromatin

18 Case #1 Histologic Description (summary): Sheets of tightly packed neoplastic round cells infiltrate the marrow cavity of the vertebral body. The cells are round with distinct cell margins and a moderate amount of pale basophilic cytoplasm with occasional perinuclear clearing. The nuclei are round with clumped chromatin Morphologic Diagnosis:

19 Case #1 Histologic Description (summary): Sheets of tightly packed neoplastic round cells infiltrate the marrow cavity of the vertebral body. The cells are round with distinct cell margins and a moderate amount of pale basophilic cytoplasm with occasional perinuclear clearing. The nuclei are round with clumped chromatin Morphologic Diagnosis: Myeloma, vertebral body Possible clinical pathology findings:

20 Case #1 Histologic Description (summary): Sheets of tightly packed neoplastic round cells infiltrate the marrow cavity of the vertebral body. The cells are round with distinct cell margins and a moderate amount of pale basophilic cytoplasm with occasional perinuclear clearing. The nuclei are round with clumped chromatin Morphologic Diagnosis: Myeloma, vertebral body Possible clinical pathology findings: Hypergammaglobulinemia, hypercalcemia, Bence-Jones proteinuria

21 courtesy of Dr A Matthews AVC Ancillary / helpful diagnostic findings Hypercalcemia increased osteoclastic activity within bone lesions courtesy of Dr. A Matthews, AVC Hypergammaglobulinemia clonal neoplastic plasma cells secrete Ig s (or Ig fragments) of one class, ie monoclonal gammopathy Bence-Jones proteinuria Immunoglobulin light chains pass through glomeruli into urine Radiographs showed punched out lesions in the vertebrae

22 Case #2 Signalment: 1.5 year old, laying hen History: The bird has been down for a day and has not been eating All images for this case were provided by Dr Heather Fenton, AVC

23 Spleen Liver Bone

24 Spleen Normal chicken spleen

25 Spleen Gross Description

26 Spleen Gross Description The spleen is markedly enlarged and misshapen with coalescent yellow-tan nodules scattered over the surface

27 Spleen Gross Description These extend into the parenchyma on cut surface

28 Spleen Histologic Description

29 Spleen Histologic Description Discrete eosinophilic nodules are present within the spleen.

30 Spleen Histologic Description

31 Spleen Histologic Description The nodules are composed of central regions of necrosis surrounded by a thick cellular rim. What are the cells?

32 Spleen Histologic Description The nodules are composed of central regions of necrosis surrounded by a thick cellular rim. What are the cells?

33 Spleen Histologic Description The cells consist primarily of epithelioid macrophages and rare heterophils. Admixed with these cells are occasional lymphocytes, plasma cells and fibroblasts and what other cell type?

34 Spleen Histologic Description Scattered multinucleated giant cells

35 Spleen Morphologic Diagnosis

36 Spleen Morphologic Diagnosis Splenitis, granulomatous, multifocal to coalescing, chronic, marked

37 Spleen Acid-fast stain Etiology and Disease Name

38 Spleen Acid-fast stain Etiology and Disease Name Etiology: Mycobacterium avium Disease Name: Avian tuberculosis

39 Case #2 Histologic Description (summary): Scattered throughout the spleen are discrete foci of necrosis surrounded by infiltrates of epithelioid macrophages and multinucleated giant cells admixed with fewer lymphocytes and plasma cells Acid-fast bacilli are present within the lesion Morphologic Diagnosis: Splenitis, granulomatous, multifocal to coalescing, chronic, marked, with intralesional acid-fast bacilli Etiology and Disease Name: Mycobacterium avium Avian tuberculosis

40 Case #2 Avian Tuberculosis Mycobacterium avium complex (serotypes 1, 2 and 3) Can infect an extensive range of species In birds usually chickens, captive wild birds and turkeys Free range farming systems and keeping breeders for several years are conducive to the spread of this disease. Main sources of infection are infected individuals and the contaminated environment (water and soil) Affects multiple organs Granulomatous osteomyelitis and hepatitis

41 Case #3 Signalment: 9 yr-old MC cat History: Cat had been anorexic and was beginning to lose weight. On physical exam the cat was dehydrated. Abdominal palpation revealed enlarged irregular kidneys. Blood chemistry revealed elevated urea and creatinine.

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43 Gross Description Marked enlargement of the kidneys Nodular/irregular capsular surface

44 Gross Description

45 Gross Description On cut surface, there are multifocal to coalescing, white, round to irregular masses scattered throughout both of the kidneys

46 Morphologic Diagnosis

47 Morphologic Diagnosis Multiple renal masses, probable malignant neoplasia

48 Need Histology! Feline Infectious Peritonitis (Pyogranulomatous nephritis) Compare previous slides with this case of multifocal granulomatous nephritis due to FIP. These lesions can easily be mistaken for renal lymphoma! Two main differentials for this lesion in cats: Lymphoma and FIP Renal lymphoma

49 LYMPHOMA Renal lymphoma vs. Pyogranulomatous nephritis (FIP, dry form) Renal lesions, cat FIP

50 Histologic Description

51 Histologic Description At low power, we can appreciate a nodule within the tissue (kidney) that looks more blue than normal suggests an increase in the cellularity of the tissue

52 Histologic Description Description: Densely cellular sheet-like infiltrates efface the normal renal architecture leaving few remaining glomeruli

53 At 40x

54 Histologic Description These cells have distinct cell margins, scant eosinophilic cytoplasm, and round nuclei with stippled chromatin and prominent nucleoli. Mitoses are present (arrow).

55 Case #3 Histologic Description (summary): In this section of kidney, most of the normal architecture has been effaced by dense sheet-like cellular infiltrates consisting of large numbers of neoplastic round cells. These neoplastic round cells have small amounts of well-delineated pale acidophilic cytoplasm. The nuclei are round to slightly ovoid with stippled chromatin and distinct nucleoli. Morphologic Diagnosis: Renal lymphoma Comments: Lymphoma is the most common renal tumor in the cat. It may cause kidney deficiency/failure by destroying parenchyma or by obstructing urine outflow

56 Gross Description The inguinal and mesenteric lymph nodes are moist, pale and enlarged 2-3 times normal size. Morphologic diagnosis: Inguinal/ mesenteric lymphadenomegaly Case #4 Images from Noah s arkive

57 Gross Description The pericardial and bone marrow fat tissue are replaced by clear yellow gelatinous material. Morphologic diagnosis: Pericardial and bone marrow fat: Serous atrophy, diffuse, marked. From Noah s arkive

58 Case #4 Etiology / Disease: Porcine circovirus type 2 / Postweaning multisystemic wasting syndrome Histology: Granulomatous infiltration of the node (diffuse granulomatous lymphadenitis) with large botryoid intracytoplasmic viral inclusions Images from Noah s arkive

59 7 year-old cow with posterior paralysis Description: Cross section of spinal cord (lumbar segment) compressed by a subdural (intradural) white, solid, ovoid mass. Morphologic diagnosis: 1. Subdural lymphoma 2. Spinal cord compression; lumbar segment. From Noah s arkive Case #5

60 Tonsil: Squamous cell carcinoma Tonsil: Lymphoma From Noah s arkive Pathologic Basis of Veterinary Disease, 4 th ed.

61 Splenic hematoma, dog. Locally, there is marked expansion and replacement of the splenic parenchyma by a mass of blood. The capsule is markedly distended; cut surface reveals extensive areas of necrosis and fibrin.

62 Splenic Nodules important differentials Splenic nodules with a bloody consistency Hematoma Hemangioma Hemangiosarcoma Splenic infarcts Incompletely contracted areas of the spleen Splenic nodules with a firm consistency Nodular hyperplasia Primary Neoplasia (eg lymphoma, histiocytic sarcoma) Metastatic (secondary) Neoplasia Abscess Granuloma

63 Diffuse Splenomegaly important differentials Diffuse splenomegaly with a bloody consistency = Bloody Spleens Acute septicemia Acute hemolytic anemia Splenic torsion Barbiturate anesthesia/euthanasia Vascular pooling Diffuse splenomegaly with a firm consistency = Meaty Spleens Septicemia Salmonella Hemolytic anemia Neoplasia eg lymphoma, mast cell tumor, histiocytic sarcoma Granulomatous disease Amyloidosis

64 Siderofibrosis = Gamna-Gandy bodies, siderocalcified plaques Histo: Hematoidin, hemosiderin and mineral deposits Pathologic Basis of Veterinary Disease, 4 th ed.

65 Splenic hemangiosarcoma, dog. Multiple, variable sized, dark red, soft (bloody) nodular masses. These lesions often develop infarction and/or rupture, followed by bleeding.

66 Splenic lacerations and hematoma in horse that was hit-by-car

67 Splenic lacerations and hematoma in horse that was hit-by-car