A mass was palpated in the abdomen of an intact, 2-year-old, female, mixed-breed dog. Her last estrous cycle was 1 month before presentation. The dog had regenerative anemia (hematocrit, 25.3%) with neutrophilia and thrombocytopenia. Serosanguineous fluid had been found in the abdomen and evaluated cytologically. There was a moderate amount of red blood cells (850,000 cells/µl) and numerous nucleated cells (38,200 cells/µl). The nucleated cells were mostly degenerated neutrophils. There were also macrophages and reactive mesothelial cells, a few columnar cells with round basal nuclei and prominent apical cilia, and a moderate number of free cilia in the sample. The cytologic determination was pyogranulomatous exudate with moderate mesothelial reactivity; recent hemorrhage; and ciliated epithelial cells, probably of oviductal origin. Ovariohysterectomy was performed, at which time a large, pedunculated mass arising from the left oviduct was removed. Histopathologic diagnosis of the mass was oviductal hamartoma. To the author's knowledge, this is the first reported case of an oviductal hamartoma in any species.

COMMENTARY: It is unusual to find ciliated cells in the abdominal fluid. There were many ciliated epithelial cells in the tumor of this dog, which probably exfoliated from the mass. When ciliated epithelial cells are found in abdominal fluid, be suspicious of an oviductal lesion.

Abdominal fluid from a dog. Fry MM, DeCock HEV, Greely MA, Vernau W. VET CLIN PATHOL 32:77.