Infectious Dx: Febrile Neutropenia

Question 1

What are the three primary reasons by which febrile neutropenia can develop?

Answer 1

Increased tissue usage of neutrophils, the decreased movement of neutrophils from the bone marrow, and immune-mediated destruction of neutrophils

Question 2

Life threatening infections in neutropenic patients often come from their own -?

Answer 2

Commensal microflora

Question 3

True or False: Cells including macrophages, monocytes, endothelial cells, and fibroblasts, in addition to stromal cells within the bone marrow, are capable of producing GCSF for neutrophil production.

Answer 3

True

Question 4

What term is used to describe the increased production of leukocytes outside of a more steady-state production of neutrophils?

Answer 4

Emergency myelopoiesis

Question 5

True or False: Cats will have more neutrophils present in the circulating pool rather than the marginal pool, compared to dogs.

Answer 5

False, dogs have half of their neutrophils in circulation while cats have a quarter of their neutrophils in circulation

Question 6

Due to reduced levels of circulating neutrophils, reduced levels of chemokines in the bone marrow leads to -?

Answer 6

Increased movement of neutrophils out of the bone marrow and into circulation

Question 7

Describe ineffective granulopoiesis.

Answer 7

This is a term used to describe the presence of adequate granulocyte precursors in the bone marrow, coupled with peripheral neutropenia.

Question 8

What are examples of ineffective granulopoiesis?

Answer 8

Infectious diseases, hereditary diseases, toxicants, medications, infectious diseases, and neoplasia

Question 9

What are examples of infectious diseases that can cause a depletion of granulocyte progenitor cells in cats and dogs?

Answer 9

FeLV, FIV, rickettsial diseases, and Canine parvovirus

Question 10

What are examples of medications and toxicants that can cause a depletion of granulocyte progenitor cells?

Answer 10

Phenylbutazone, Methimazole, Estrogen, chemotherapeutic agents, and antiepileptics

Question 11

What neoplastic processes can be associated with the depletion of granulocyte progenitor cells?

Answer 11

Sertoli cell tumors and round cell neoplasms including leukemias, lymphomas, multiple myeloma, histiocytic sarcoma

Question 12

What diagnostic tests can be considered to determine the underlying cause for neutropenia?

Answer 12

Blood cultures, urinalysis and culture, diagnostic imaging (radiographs, ultrasound), and bone marrow evaluation

Question 13

Treatment and supportive care for neutropenic patients includes -?

Answer 13

Broad spectrum antimicrobial therapy, antifungal therapy, fluid therapy, and recombinant G-CSF is possible

Other preventative measures including isolation and appropriate hygiene practices