Massive ascites caused by peritoneal extramedullary hematopoiesis as the initial manifestation of myelofibrosis

Idiopathic myelofibrosis accompanied by peritoneal extramedullary hematopoiesis presenting as refractory ascites in a dog

A 2.5-year-old spayed female American Pit Bull Terrier dog presented with a primary complaint of chronic refractory ascites. The dog's CBC displayed a moderate to severe macrocytic, hypochromic, nonregenerative anemia, and a moderate leukopenia as result of a moderate neutropenia and monocytopenia. Microscopic examination of the blood smear showed marked anisocytosis, mild polychromasia, mild acanthocytosis and ovalocytosis, moderate schistocytosis and poikilocytosis, and 4 metarubricytes/100 WBC. Abdominal ultrasonography revealed a homogenous, mild to moderately hyperechoic appearing liver as well as marked amounts of speckled anechoic to slightly hypoechoic peritoneal fluid. Cytology of the ascitic fluid demonstrated a sterile transudate, with evidence of a chronic inflammatory reaction as well as erythroid and myeloid precursor cells, and a few megakaryocytes with occasional micromegakaryocytes. Histologic sections of bone marrow, spleen, and liver were examined, using routine H&E stains, as well as a variety of immunohistochemistry and other special stains. Histopathology of the bone marrow and spleen revealed varying degrees of fibrosis, erythroid, and myeloid hyperplasia, as well as multiple small hyperplastic clusters of megakaryocytes. The megakaryocytes displayed many features of atypia such as increased cytoplasmic basophilia and occasional abnormal chromatin clumping with mitoses. Histopathologic examination of the liver disclosed evidence of mild extramedullary hematopoiesis. This case represents the first report of canine idiopathic myelofibrosis associated with peritoneal extramedullary hematopoiesis, resulting in refractory ascites. Although idiopathic myelofibrosis is a relatively rare condition in dogs, this case demonstrates that ascites caused by peritoneal implants of hematopoietic tissue may be the initial manifestation of myelofibrosis.

Nontuberculous mycobacterial infection in a patient with myelofibrosis: case report and concise review

A 70-year-old patient having massive refractory ascites in the course of idiopathic myelofibrosis was diagnosed of peritoneal extramedullary hematopoiesis and developed an overwhelming nontuberculous mycobacterial infection. The case describes this unusual infection and highlights the need for additional studies to confirm the etiology of ascites in primary myelofibrosis.

Intestinal obstruction caused by extramedullary hematopoiesis and ascites in primary myelofibrosis

Primary myelofibrosis (PMF) is a clonal hematopoietic stem cell disorder. It is characterized by bone marrow fibrosis, extramedullary hematopoiesis with hepatosplenomegaly and leukoerythroblastosis in the peripheral blood. The main clinical manifestations of PMF are anemia, bleeding, hepatosplenomegaly, fatigue, and fever. Here we report a rare case of PMF with anemia, small bowel obstruction and ascites due to extramedullary hematopoiesis and portal hypertension. The diagnosis was difficult to establish before surgery and the differential diagnosis is discussed.

A patient with myelofibrosis complicated by refractory ascites and portal hypertension: to tips or not to tips? A case report with discussion of the mechanism of ascites formation

In patients with myelofibrosis, clinically significant portal hypertension is known to be predominantly presinusoidal; however, the exact mechanisms are still controversial. The pathophysiology is particularly enigmatic in those patients without histological and angiographic evidence of significant intra- or extrahepatic obstruction to portal blood flow, respectively. Moreover, ascites formation has been reported in such cases, but in general is rare in presinusoidal portal hypertension. Here we present such a patient in which ascites developed even in the presence of unchanged serum protein levels (oncotic pressure) and was refractory to sodium restricted diet and high-dose diuretic treatment. A discussion on the parameters influencing fluid exchange and ascites formation particularly emphasizing the potential importance of the hyperdynamic circulation in this case is given. Finally, the patient was treated by implanting a transjugular intrahepatic shunt (TIPS), exerting a diuretic effect sufficient enough to avoid re-formation of ascites for several months. However, ascites re-accumulated potentially due to the appearance of ectopic peritoneal myeloid metaplasia and the patient died soon afterwards. In conclusion, TIPS may be considered as rescue management for refractory ascites secondary to portal hypertension, but caution in respect to the presence and/or development of peritoneal or other ectopic haematopoesis has to be taken.