Hemolymph Flashcards
Three components of anthratoxin (A-B toxin)
Protective antigen (II)- B subunit (entry), binds TEM8 and CMG2
Lethal factor (III)- A subunit, cell death, CNS depression
Edema factor (I)- A subunit, increases cAMP–>water efflux from cell
How to diagnose anthrax?
Blood smear from tail tip or coronary band
What is the key histo on blood smear?
Intravascular large bacilli with flat ends
Pathogenesis of anthrax
Initial lymphangitis/lymphadenitis, then septicemia
How to stain anthrax?
Old methylene blue stains pink, distinct capsule
Classical swine fever lesions
Lymphocytolysis (thymus and lymphoid atrophy)
Differentials for congested splenomegaly in a pig
Volvulus, salmonella, hemolytic anemia, Mycoplasma haemosuis, African swine fever
Cause of cervical lymphadenitis in the guinea pig
Streptococcus equi ssp. zooepidemicus
What predisposes G pigs to lumps?
Female sex and stress
Key histo with cervical lymphadenitis
Bilateral suppurative lymphadenitis
What does mycobacterium avium subsp. paratuberculosis target?
M cells (GALT, PP)
Virulence factors of mycobacterium
Lipid rich cell wall
Peroxidase
Man-LAM
TLR2 and IL10 stimulate TH2 response
What does mycobacterium require for growth? Where is it highest?
Iron; ileocecal jxn
Mycobacterium key histo
Granulomatous lymphangitis/lymphadenitis
Yersinia pseudotuberculosis clinical presentation
GI disease with lymphadenopathy in cats and rodents
Yersinia pseudotuberculosis virulence factors
Yersinia adhesion A protein, YadA (adheres to ECM and inhibits complement)
Invasin and Ail (bind to M cells)
YopB and Yop D for type III SS, injects effector Yops that alter phagocyte fxn (Yop E/H/T)
Y. pseudotuberculosis key histo
Large, botryoid colonies of bacteria (lymphadenitis), lymphoid hyperplasia and histiocytosis
How is Y. pestis different?
Does not cause disease in rodents, and three forms:
Bubonic plague, pneumonia, or septicemic
Corynebacterium pseudotuberculosis virulence factors
Leukotoxic surface lipid (mycolic acid)- induces inflammation, prevents phagolysosome formation
Exotoxin (phospholipase D) increases vascular permeability, cell damage
Key gross and histo for corynebacterium
Onion skin lymphadenomegaly, caseous lymphadenitis in sheep, ulcerative lymphangitis in horses/cows; eosinophils, no colonies
Key histo for actinobacillus lignieresii
Pyogranulomatous inflammation with large colonies of bacilli with Splendore-Hoeppli (sulfur granules grossly)
Key histo for Francisella tularensis
Abscesses with a ton of necrosis in multiple organs (LN, liver, spleen)
How to tell tularemia from yersinia
No colonies in tularemia
What cells does bartonella henselae infect?
Erythrocytes
Endothelium
Macrophages
How is bartonella transmitted
Arthropods
Histo with bartonella; stain to see?
Lymphadenitis; silver stains
How is Neorickettsia helminthoeca transmitted?
Ingestion of trematode (Nanophyteus salmincola*)
Life cycle of Nanophyteus salmincola
1st IH- snail, cercaria
2nd IH- fish, metacercari
DH- fish eating mammals
Stains to see Neorickettsia helminthoeca
Giemsa, Macchiavellos
Key histo with Neorickettsia helminthoeca
Lymphoid depletion, histiocytosis*, pleomorphic organisms in macrophages (hard to see), adult trematodes in intestines
How is Ehrlichia canis transmitted?
Rhipicephalus sanguineus
Who is susceptible to E. canis?
GSDs
Where does E. canis live?
Lymphocytes and monocytes
Clinical pathology with E. canis
Thrombo- and pan-cytopenia
Key cyto with E. canis
Morulae on blood smears or synovial fluid smears
What kind of fungus is Sporothrix schenckii?
Dimorphic
Three types of sporothricosis
Cutaneous, cutaneous-lymphatic, disseminated
Key histo with Sporothrix schenckii
Pyogranulomatous lymphadenitis with intrahistiocytic and extracellular cigar-shaped 2-10um yeast with a halo
What is the pelger-huet anomaly?
Normal leukocytes count, but left shift due to hyposegmentation of granulocytes and monocytes (round/kidney nucleus)
What causes Pelger-Huet anomaly?
Lamin B receptor mutation (autosomal dominant)
Cause of SCID in horse?
Arabian horses- autosomal recessive defect in PRKDC gene
Cause of SCID in dog?
Defect in type I cytokine receptor
Clin path findings supportive of SCID
Lymphopenia, hypogammaglobulinemia, no IgM
Key histo with SCID
Lymphoid hypoplasia of all lymphoid organs
Who gets congenital dyserythropoiesis
Polled Herefords; idiopathic in English springer spaniels with polymyopathy and megaesophagus
Syndromes assocaited with congenital dyserythropoiesis
Anemia, progressive alopecia, dyskeratosis
Key histo with congenital dyserythropoiesis
Marked erythroid hyperplasia (arrest at rubricyte stage), epidermal dyskeratosis*
Who gets LAD?
Holsteins; Irish setters
Cause of LAD?
Deficiency of beta 2 integrins (CD18)
Pathogenesis of LAD
Neutrophils can’t adhere, diminished chemotaxis–>recurrent infections–>persistent neutrophilia
Who gets thymomas?
Adult female goats
List of paraneoplastic syndromes associated with thymoma
Myasthenia gravis w. megaesophagus
Exfoliative dermatitis
Eosinophilia
Hypercalcemia
Polymyositis
Exophthalmia in rabbits
Red cell aplasia
T cell lymphocytosis
Thymoma types and appearance
Type A- spindle
Type B- epithelioid (dog); B1 most closely resembles the normal thymus, B3 more epithelial
Type AB- components of both, sheep/goats
Cause of malignant lymphoma in cats; only transmissible type
Feline Leukemia Virus A
What kind of virus is FeLV
Lentivirus (gammaretrovirus)
What type of lymphoma occurs with FeLV
Thymic T cell lymphoblastic
FeLV virulence factors
gag- infectivity
env- attachment and entry
pol- enzymes
What kind of lymphoma is associated with FIV?
B cell lymphoma of intestine
Most common lymphoma in cats
T cell intestinal lymphoma
What phenotype is gastric lymphoma?
Diffuse large B cell
What phenotype is nasal lymphoma?
Diffuse large B cell
From what does histiocytic sarcoma arise?
Interstitial dendritic cells
What stain is used for histiocytic sarcoma?
CD18
Mice strains predisposed to HS
B6 SJL
Histo finding in rats associated with HS
Intracytoplasmic hyaline droplets in PCTs
Only malignancy of macrophage origin
Hemophagocytic histiocytic sarcoma
Benign tumor that cheetahs get
Myelolipoma (liver); spleen in dog
Features of T zone lymphoma- cell size and type, pattern, key histo, location, behavior
Intermediate T cells; nodular; peripheralizes and fading follicles; lymph nodes; indolent
Features of marginal zone lymphoma- cell size and type, pattern, key histo, location, behavior
Intermediate B cells with large central nucleolus; nodular; around fading follicles; spleen, LNs, extranodal; indolent
Where does mycoplasma haemocanis live?
Epicellular on erythrocytes (perimembranous)
Disease with mycoplasma?
Hemolytic anemia if immunocompromised/splenectomized
Key cyto with mycoplasma
Thin chains of cocci on erythrocytes
How is mycoplasma transmitted?
Blood sucking arthropods (like mycoplasma suis! Haematopinus)
What type of organism is Babesia?
Apicomplexan protozoan, tickborne
What cell does Babesia infect?
Erythrocytes
Disease with Babesia?
INTRAVASCULAR hemolysis (so, jaundice), vascular sludging (cerebral flush), hypotension
Key cyto with babesia
Intraerythrocytic paired pear-shaped piroplasms
What type of organism is Plasmodium?
Apicomplexan protozoan, arthropod borne
Natural host of Plasmodium?
Cyno macaque
Life cycle of Plasmodium?
Indirect two host- Sexual stage in arthropod, asexual stage in vertebrate
What cells does Plasmodium infect?
Liver phase- macrophages and endothelial cells
Erythrocytic phase- RBCs
Key gross findings with Plasmodium
Brown discoloration (hemazoin pigment)
Key histo with Plasmodium
Schizonts in macs, endothelial cells
Trophozoites, meronts, or gametocytes in erythrocytes
What type of organism is Cytauxzoon?
Protozoan, tickborne
Reservoir for Cytauxzoon
Bobcat
Disease with cytauxzoon
Hemolytic anemia and vascular occlusion
Key cyto with Cytauxzoon
Piroplasms within erythrocytes (non-replicating phase), intrahistiocytic schizonts with merozoites occluding vessels
Key clin path finding with Cytauxzoon
Lymphocytosis and monocytosis
Key histo with Cytauxzoon
Birefringent hemazoin pigment
What type of organism is Theileria?
Apicomplexan protozoan, tickborne
Disease with Theileria
High fever and lymphadenopathy in cattle
Key histo with theileria
Diffuse lymphoid hyperplasia with lymphoblasts and intracytoplasmic schizonts (Kochs blue bodies)
Stain to identify Theileria
Giemsa
Life cycle of Theileria (cells infected)
Schizogeny in lymphocytes (tissue phase)- Macroschizonts–>microschizonts–>merozoites released
Found in erythrocytes (erythrocytic phase)- Merozoites
What type of organism is Leucocytozoon
Insectborne (flies) protozoan
Disease seen in birds with Leucocytozoon
INTRAVASCULAR hemolysis and anemia
Cells infected/life cycle with Leucocytozoon
Asexual schizogeny in liver, lung, vessels
Gametogony- Megaloschizonts in endothelial and RBCs
What kind of organism is Leishmania
Obligate diphasic (promastigotes and amastigotes) intracellular protozoan
How is Leishmania transmitted/intermediate host?
Sandflies
What cells does Leishmania infect?
Histiocytes, other leukocytes, endothelial cells, fibroblasts
Common clinical presentation of Leishmania
Hyperproteinemia with hypergammaglobulinemia (plasma cell hyperplasia) and hypoalbuminemia (proteinuric nephritis)
Which immune response is more effective against Leishmania
Th1
Key histo with Leishmania
Intrahistiocytic amastigotes with a rod shaped perpendicular kinetoplast
Stain for Leishmania
Giemsa
Life cycle of Leishmania
Amastigotes bust out of WBCs ingested by sandfly, transform into promastigotes, replicate in midgut, transition to metacyclic form (infectious), injected with saliva into DH
Three forms of Leishmania
Cutaneous
Mucocutaneous (spread of cutaneous to nasopharynx)
Visceral
What organism is a schistosome?
Blood fluke, (intravascular) trematode
What is the intermediate host of schistosoma
Snail- releases infective cercariae
Other than being intravascular, why is this fluke (schistosoma) weird?
Not hermaphroditic (other flukes are)
Key histo for schistosomiasis
Granulomatous inflammation, fibrosis, trematode eggs (yellow-brown, miracidium, no operculum, maybe spines); eosinophilic endophlebitis
What virus is Marek’s disease caused by?
Gallid herpesvirus 2 (Alphaherpesvirus)
What cell does gallid herpesvirus 2 infect?
T lymphocytes
Age range affected by Marek’s
2-5 months
Where does the Marek’s virus replicate?
Follicular epithelium- infected by inhaling follicle dander
Important genes for Marek’s virus (3)
Meq (oncogene)
vTR (telomerase)
pp38 (replication)
Stains for Marek’s disease
CD3
MATSA tumor antigen
Meq
Classic presentation of Marek’s
Sciatic nerve enlargement (neurolymphomatosis)
Paralysis (splay leg)
Ocular/cutaneous- grey eye color
Visceral tumors
What kind of organism is isospora?
Apicomplexan protozoa
Who gets isosporosis
Passerines
Like cycle of isospora
Sexual reproduction in enterocytes (fecal oral transmission)
Asexual reproduction in lymphocytes, and macrophages
Presentation of isospora
In fledglings- acute mortality
Mimics lymphoma
Key gross finding in isospora in general; specifically in finches; specifically in white rumped shama
General- Splenomegaly
Finches- Duodenal thickening
Shama- skin and macrophages
Key histo in isospora
Lightly basophilic protozoal merozoites with clear halo (p.vacuole) within lymphocytes, indenting the nucleus
with lymphohistiocytic inflammation in various organs
Natural host of herpesvirus saimiri
Squirrel monkey
Susceptible species to herpesvirus saimiri
Rabbits, NWMs
What kind of virus is herpesvirus saimiri
Gammaherpesvirus rhadinovirus
What disease does herpesvirus saimiri cause?
Fatal lymphoproliferative (CD3/CD8 T cell)
Herpesvirus saimiri virulence factors
Saimiri transformation-associated protein (StpC)
Tyrosine kinase interacting protein (Tip)
Key gross with herpesvirus saimiri
Nodular lesions in liver, spleen, kidney, orbit, abdomen
What kind of virus causes Pacheco’s disease?
Psittacid herpesvirus 1 (alphaherpesvirus)
Who is particularly susceptible to Pacheco’s?
Cockatoos and Amazon parrots
What disease does Pacheco’s cause?
Acute fatal hepatitis
Where does Pacheco’s go latent?
Trigeminal
Lymphoreticular system
Key gross with Pacheco’s; key histo
Hepatic and splenic necrosis; eosinophilic intranuclear inclusion bodies with syncytia, necrosis in liver, spleen, intestine
What kind of virus is simian hemorrhagic fever
Arterivirus
What cell is targeted with simian hemorrhagic fever
Macrophages
Who are subclinical carriers of simian hemorrhagic fever
Patas
African green monkeys
Baboons
Key gross with simian hemorrhagic fever
Hemorrhage/congestion of proximal duodenum**
Hemorrhage/congestion of other viscera (like DIC)
Absent hepatic/adrenal necrosis- differentiates from other scary viruses
Key histo with simian hemorrhagic fever
Lymphoid necrosis
Perifollicular splenic hemorrhage and fibrin
Thymic cortical necrosis with medullary sparing**
What kind of virus is African swine fever?
Asfarvirus
How is ASF different from CSF?
ASF does not infect epithelium
Vector of African swine fever
Soft tick- ornithodoros moubata
What cell is targeted with African swine fever
Macrophages
Key gross lesions of African swine fever
Splenomegaly
LN hematoma
Key histo with African swine fever
Fibrinoid vasculitis, hemorrhage, lymphocyte/macrophage necrosis and depletion, thrombosis
What kind of virus is classical swine fever?
Pestivirus
What test can be used for African swine fever?
p72 PCR
General disease caused by African swine fever?
High fever, cutaneous hyperemia, abortions, edema, hemorrhage in internal organs
General disease caused by classical swine fever?
Hemorrhagic disease with DIC, thrombocytopenia, and immunosuppression
What cell types does classical swine fever target?
Endothelium, epithelium, macrophages
Key gross lesions with classical swine fever
Turkey egg kidney, splenic infarcts, necrotizing tonsillitis, button ulcers
Key histo with classical swine fever
Vasculitis and lymphoid depletion
What kind of virus causes infectious bursal disease?
Birnavirus
Age group affected by infectious bursal disease
3-6 weeks
Disease caused by infectious bursal disease
Lymphocytolytic, immunosuppressive (mostly immature bursal B cells***)
Which serotype of infectious bursal disease is pathogenic?
Serotype 1
Key gross with infectious bursal disease
Enlarged, edematous bursa
Key histo with infectious bursal disease
Lymphoid necrosis and atrophy with mild inflammation
What virus causes marble spleen disease?
Siadenovirus (Turkey adenovirus 3)
Who gets marble spleen disease?
Pheasants
Whate age group is affected by marble spleen disease?
3-8 months
Cells targeted by marble spleen disease
Lymphotropic (B lymphocytes) and lymphocytopathic
Key histo with marble spleen disease
Basophilic INIBs in WBCs, white pulp hyperplasia then necrosis
Key gross with marble spleen disease
Splenomegaly
Canine parvovirus-2 disease causes
Enteritis, cerebellar hypoplasia
Key histo with Canine parvovirus-2
Lymphoid hyperplasia then lymphocytolysis, necrohemorrhagic enteritis, INIBs in epithelium
Clin path findings with Canine parvovirus-2
Pancytopenia
Disease associated with hamster parvovirus?
Dental/facial deformities
Disease associated with Killam’s rat parvovirus?
Scrotal and cerebellar hemorrhage
What type of virus is equine infectious anemia?
Lentivirus
What cell type does equine infectious anemia infect?
Macrophages
Clin path findings with equine infectious anemia
Severe anemia and thrombocytopenia (intravascular hemolysis)
How is equine infectious anemia transmitted?
Mechanically via flies
Key histo findings with equine infectious anemia
Hemosiderosis*, bone marrow erythroid hyperplasia, bulls eye splenic follicles (enlarged by hypocellular)
What is the best diagnostic tool for equine infectious anemia?
PCR is better than coggins- catches positives before they seroconvert
What disease does porcine circovirus-2 cause?
Postweaning Multisystemic Wasting Syndrome- wasting and lymphadenomegaly
Age group affected by porcine circovirus-2
5-18 weeks
Key histo with porcine circovirus-2
Lymphoid depletion, granulomatous lymphadenitis, IC botryoid inclusions in histiocytes
Which porcine circovirus-2 is the least virulent?
2e
How to differentiate porcine circovirus-2 from PRRS
Bronchial necrosis in PRRS
What type of virus causes ebola?
Filovirus
What syndrome does ebola cause?
Highly fatal hemorrhagic fever of primates
Reservoir of ebola
Fruit bats
What cells does ebola target?
Macrophages
Classic gross lesion with ebola
Hemorrhage of proximal duodenum** (like simian hemorrhagic virus)
Key histo with ebola
Lymphoid necrosis surrounded by hemorrhage, necrosis of liver and adrenal (unlike SHV)