Page 1414 - Small Animal Internal Medicine, 6th Edition

1386 PART XIII Hematology

features associated with myelofibrosis in dogs frequently
resolve after immunosuppressive treatment with a combina-
VetBooks.ir tion of corticosteroids and azathioprine (see Chapter 72).
A presumptive diagnosis of osteosclerosis or osteopetro-
sis is made on the basis of the presence of combined cytope-
nias together with increased osseous radiographic density
and can be confirmed by a core biopsy of the BM. Unfortu-
nately, no effective treatment is currently available.
Suggested Readings

Abrams-Ogg ACG, et al. Comparison of canine core bone marrow
biopsies from multiple sites using different techniques and
needles. Vet Clin Pathol. 2012;41:235.
Couto CG, et al. Preleukemic syndrome in a dog. J Am Vet Med
Assoc. 1984;184:1389.
Harvey JW. Canine bone marrow: normal hematopoiesis, biopsy
FIG 86.3 techniques, and cell identification and evaluation. Compend Cont
Elliptocytosis in an Airedale Terrier with myelofibrosis. Educ. 1984;6:909.
Elliptocytes (arrows) are intermixed with normal RBCs and Kunkle GA, et al. Toxicity of high doses of griseofulvin in cats. J
spherocytes. The patient had complete resolution of the Am Vet Med Assoc. 1987;191:322.
hematologic and morphologic RBC changes after treatment Maggio L, et al. Feline preleukemia: an animal model of human
with corticosteroids and azathioprine (Wright-Giemsa stain; disease. Yale J Biol Med. 1978;51:469.
×1000). Moretti P, et al. Nucleated erythrocytes in blood smears of dogs
undergoing chemotherapy. Vet Comp Oncol. 2015;15:215.
Reeder JP, et al. Effect of a combined aspiration and core biopsy
inductor of differentiation (see Box 80.3). Novel therapeutic technique on quality of core bone marrow specimens. J Am Anim
approaches in humans with MDS include primarily target- Hosp Assoc. 2013;49:16.
ing the MDS clone or using nonspecific azanucleosides such Scott-Moncrieff JCR, et al. Treatment of nonregenerative anemia
as azacytidine, targeted molecular therapy, immunotherapy, with human gamma-globulin in dogs. J Am Vet Med Assoc.
and hypomethylating agents. 1995;206:1895.
Turinelli V, Gavazza A. Retrospective study of 152 feline cytological
MYELOFIBROSIS AND OSTEOSCLEROSIS bone marrow examinations: preliminary classification and
ranges. J Fel Med Surg. 2018;[epub ahead of print].
Fibroblasts or osteoblasts within the BM can proliferate in Turinelli V, et al. Canine bone marrow cytological examination,
response to retroviral infections, chronic noxious stimuli, or classification and reference values: a retrospective study of 295
unknown causes, leading to fibrous or osseous replacement cases. Res Vet Sci. 2015;103:224.
of the BM cavity, thereby displacing the hematopoietic pre- Weiss DJ. A retrospective study of the incidence and the classifica-
cursors. These syndromes are termed myelofibrosis and osteo- tion of bone marrow disorders in the dog at a veterinary teaching
sclerosis, respectively. Although both syndromes are rare, hospital (1996-2004). J Vet Intern Med. 2006;20:955.
they have been observed in FeLV-infected cats and in dogs Weiss DJ. Bone marrow necrosis in dogs: 34 cases (1996-2004). J
with chronic hemolytic disorders, such as the pyruvate Am Vet Med Assoc. 2005;227:263.
kinase deficiency anemia. Peripheral blood elliptocytosis Weiss DJ. Hemophagocytic syndrome in dogs: 24 cases (1996-2005).
J Am Vet Med Assoc. 2007;230:697.
and dacryocytosis appear to be a common feature in dogs Weiss DJ, et al. A retrospective study of canine pancytopenia. Vet
with myelofibrosis (Fig. 86.3). A limited number of dogs and Clin Pathol. 1999;28:83.
cats with idiopathic myelofibrosis have been reported; in Weiss DJ, Smith SA. A retrospective study of 19 cases of canine
some of these cases, previous exposure to drugs (e.g., phe- myelofibrosis. J Vet Intern Med. 2002;16:174.
nobarbital, phenytoin, phenylbutazone, colchicine) was doc- Weiss DJ, Smith SA. Primary myelodysplastic syndromes of dogs:
umented. In my experience, the clinical and hematologic a report of 12 cases. J Vet Intern Med. 2000;14:491.