Ehrlichiosis & Anaplasmosis, Salmon Poisoning

Ehrlichia and Anaplasma are gram ___ bacteria. Where do they live in the body?

Gram negative

Intracellular obligatory- leukocytes and platelets

T/F Ticks are not true reservoirs of Ehrlichia and Anaplasma

True

What are the 2 disease types cause by Ehrlichiosis?

Monocytic

Granulocytic

How is Monocytic Ehrlichiosis aqcuired?

An uninfected larvae eats from an infected host. The larvae is now infected turns into nymph, Nymph go and feed on another host and pass it to that host, etc

Why is it difficult to control Monocytic Ehrlichiosis?

Adult infected ticks can survive 2 years and transmit for at least 150 days

Acute phase signs of Monocytic Ehrlichiosis

8-20 days post infection

lasts 2-4 weeks

Nonspecific signs

Mild thrombocytopenia, anemia and leucopenia

Subclinical phase of Monocytic Ehrlichiosis

40 days to several years

No signs (thrombocytopenia)

Immunocompetent animals can eliminate the organism

Can dogs previously infected with Monocytic Ehrlichiosis be infected again?

Yes, and with different strains

Chronic phase signs of Monocytic Ehrlichiosis

Vague signs

Organ failure

Severe hematological changes

Multisystemic signs of Monocytic Ehrlichiosis

Lethargy, weight loss

Superficial bleeding

Lymphadenomegaly

Splenomegaly

Neuromuscular signs of Monocytic Ehrlichiosis

Meningitis

Intracranial dz

Polymyosistis

Polyarthritis

Ocular signs of Monocytic Ehrlichiosis

Anterior uveitis

Chorioretinitis

What is the hallmark of chronic Monocytic Ehrlichiosis

Pancytopenia

In Monocytic Ehrlichiosis, when do we see with antibodies, urine, and mast cells?

Hyperglobulinemia (mono or poly)

Proteinuria

Mast Cell Pleocytosis

Why might you have a false negative on an Ehrlichia snap test?

Test was done too soon, takes 28 days to seroconvert, will be sick before then

Why might you have a false positive on an Ehrlichia snap test?

Previous exposure- antibodies may persist for over a year and the illness could not be related.

Is searching a blood smear for Monocytic Ehrlichiosis recommended? What are you searching for?

Looking for Morulae on a blood smear has low sensitivity. If you find it, great but don't go looking for

Why is PCR helpful for diagnosing Monocytic Ehrlichiosis? When can you get a false neg?

Ideal for confirmation of infection

However, can have false negative if P received doxycycline, collect sample first!

Monocytic Ehrlichiosis Antibiotic Therapy?

Effectiveness?

Doxycycline- signs and thrombocytopenia improve in 48 hrs

Less effective in Chronic phase

Prognosis for Monocytic Ehrlichiosis

Signs and thrombocytopenia improve in 48 hrs

Less effective in the chronic phase

Prevention for Monocytic Ehrlichiosis

Tick control!

Is Monocytic Ehrlichiosis zoonotic

Heck yes it is

E. Canis and E. Chaffeensis both cause the disease _______. What is the difference?

Monocytic Ehrlichiosis

- E. Chaffeensis causes a milder dz of fever, anterior uveitis, lymphadenomegaly, vomting, and epistaxis

E. ewingii causes a milder form(compared to monocytic ehrlichiosis) of what disease?

Granulocytic Ehrlichiosis

What is the main complaint from Granulocytic Ehrlichiosis caused by E. ewingii?

Lameness and joint edema

Does E. Ewingii cause death?

None documented

When is Granulocytic Ehrlichiosis by E. Ewingii most common?

Spring to late fall

What is the vector for Granulocytic Anaplasmosis? What does it eat?

Ixodes spp.

Equal opportunity agent(dogs, cat, horse, cow, human)

Seasons of Granulocytic Anaplasmosis

Midwest: May- June; October- November

West: April- July

Signalment of animals with Granulocytic Anaplasmosis

Older animals, 50% >6-8 yrs

People >50 yrs

Cam you be Reinfected with Granulocytic Anaplasmosis?

Yes

Also Reactivation with immunosuppression

What are the nonspecific signs of Granulocytic Anaplasmosis

Fever

Lethargy

Anorexia

What are the musculo-skeletal signs of Granulocytic Anaplasmosis

Pain

Lameness

Limb Edema

Granulocytic Anaplasmosis can cause _____ and respiratory signs.

Neuro

T/F In Granulocytic Anaplasmosis there is no bleeding and we believe no chronic disease

True

Is it fruitful to diagnose Granulocytic Anaplasmosis on Cytology?

If your find Morulae in blood or synovial fluid, great. But not sensitive

What might you see on serology of a patient with Granulocytic Anaplasmosis?

Take blood and beginning and illness and end. Will see 4 fold increase in antibodies.

Antibodies occur 2-5 dyas post morulae and persist 8-9 months. 40% of dogs are seronegative

Therapy for Granulocytic Anaplasmosis

Doxycycline- signs and thrombocytopenia improve in 48 hrs

Similar to E. Canis

Why should you not use your fingers to pull ticks?

Transmission of Granulocytic Anaplasmosis may occur direct contact with blood! The Vector also carries lyme disease. Half of symptomatic patients require hospitalization.

What causes Thrombocytic ANaplasmosis? What species is it found in

Anaplasma platys

Canine and Felines

What is the vector for Anaplasma platys?

Rhipicephalus sanguineus

Rhipicephalus linnaei

What is the difference of transmission of Anaplasma platys compared to Ehrlichea and Anaplasma phagocytophilum (granulocytic)?

There is transovarial transmission, means is spreads from generation to the next.

Why is Thrombotic Anaplasmosis descibed as "cyclic"?

Crisis for 7-10 days, then gets better in 1-2 wk intervals

Signs of Thrombotic Anaplasmosis

Fever

Hematochezia

Superficial bleeding

Anterior Uveitis

Weight loss

Option for Diagnosis of Thrombotic Anaplasmosis?

Oraganism in platelets

Serology- Dot ELISA

PCR

Is Thrombotic Anaplasmosis zoonotic?

Yes

What is the bacteria causing Salmon Poisoning Disease?

Neorickettsia helminthoeca

What relation does Elokomin fluke fever have to Salmon Poisoning Disease?

Likely another strain, high morbidity and low mortality, wider host range

What is the vector for Neorickettsia hemonthoeca? What is the host for this

Nanophyetus salmincola

Snail, fish, mammals or birds

How do dogs get salmon poisoning?

Eating fish with metacercaria

Do cats get salmon poisoningA?

No rickettsial disease, might have diarrhea

What are the stages of Salmon poisoning disease?

Incubation is 1 week-1 month

High fever -> normalizes in 4-8 days

Death in 7-10 days

What are the stages of Elokomin fluke fever?

Incubation: 5-12 days

Fever in Plateau: 4-7 days

Lower mortality

What are the signs of Salmon poisoning disease?

Anorexia

Marked weight loss

Progressive vomiting & diarrhea

Bloody diarrhea at the end

Thirst

Lrg lymph nodes

Lab changes from Salmon poisoning

Non-specific

Thrombocytopenia

Eosinophilia

Diagnosis of Salmon poisoning disease?

Trematode eggs in feces (5-8 days post infection)

Direct smear, sedimentation

FNA of lymph nodes- rickettsial bodies in mononuclear cells

Therapy for Salmon poisoning disease?

In-hospital

Supportive

Antibiotics: tetracycline

Praziquantel

Prevention of Salmon poisoning disease

Avoid raw fish

Metacercaria are viable for months

What is the agent of RMSF?

Rickettsia riskettsia

What is the vector of RMSF?

Dermacentor andersonii

Dermacentor variabilis

Amblyomma americanum

Where is RMSF most commonly found?

Southeast US

RMSF is typically an ____ disease in the months ____ through _____.

Acute

April - September

How is RMSF transmitted?

Via tick,

Transovarial transmission may occur

Time:

D. variabilis < 4 hrs

D. andersonii ??

A. aeurolatum 10 hrs (10 min if feeding is interrupted

Where does RMSF replicate in the dog?

Endothelial cells

What is the incubation period for RMSF? After one infection, can the dog get reinfected?

Incubation period is 2-14 days

Immunity in dogs is likely lifelong

Sublcinical signs of RMSF

Case in most dogs

Mild asymptomatic thrombocytopenia

Acute disease symptoms and signs of RMSF

Anorexia and fever

Neuro signs

Myalgia, arthralgia

Generalized lymphadenopathy

Peripheral edema (Face & limbs)

Arrhythmia (thrombosis and myocarditis)

Petechiae and ecchymosis in 20%

Renal Failure

Pulmonary edema

Lab findings from RMSF

Leukocytosis with left shift, monocytosis

Thrombocytopenia (consumption)

DIC

Organ failure

What is the bedside test for RMSF?

Trick question. No bedisde test. Can you doserum titers (Test initially, then 2-3 weeks post exposure) to see if there is a rise. You should see > 1:1024 or 4 fold inc in IgG titer

-subclinical infections are common and cross reactivity can occur

Antibiotics for RMSF?

Doxycyline

Enrofloxacin- don't use unless you have to

How quickly should you expect clinical signs of RMSF to improve after therapy?

Improve in 48 hours. Prognosis with therapy is fair

Prevention of RMSF

Strict tick control

Dogs may inc chances of human exposure to RMSF

People can be infected by removing ticks with hands!