February 2018 Case of the Month

Peripheral blood and pleural fluid from a dog

Case information

A 6.5 year old female spayed Cavalier King Charles Spaniel presented to the Cornell University Emergency Service for workup of an increased peripheral white blood cell count and pleural effusion detected by the primary veterinarian. Prior to presentation at Cornell, the primary veterinarian had removed approximately 300 mL of fluid from both sides of the chest. At presentation, the dog was quiet, alert, responsive, and tachypneic (44 bpm) with shallow breaths. Lung sounds were slightly decreased ventrally, compatible with an effusion. Thoracic radiographs confirmed a pleural effusion and revealed deviation of the trachea to the right with an enlarged mediastinal mass. The dog was placed into an oxygen cage due to low blood oxygen saturation (94%) on arterial blood-gas analysis and given intravenous fluid therapy at 1.5 times maintenance. Blood and pleural fluid were collected before treatment. Results are shown on the tables below.

Pertinent hematologic results
Test	Result	Units	Reference interval
Hematocrit	40	%	41-58
Retic count	0.4	%	0.2-1.5
Absolute retic count	18.9	thou/μL	11.0-92.0
White blood cells	227.6	thou/μL	5.7-14.2
Seg neutrophils	4.6	thou/μL	2.7-9.4
Band neutrophils	2.3	thou/μL	0-0.1
Other leukocytes	211.7	thou/μL	0-0.1
Platelet count	108	thou/μL	186-545
MPV	17.5	fL	8.4-14.1
Mild toxic change in neutrophils

 

Pleural fluid
Test	Result	Units
Volume	1.8	mL
Color	Medium red
Turbidity	Opaque
Total Protein (ref)	<2.5	g/dL
Nucleated cells	16.0	thou/μL
Red blood cells	178.1	thou/μL

 

 

The “other cells” are shown on the representative photomicrographs of the blood and pleural fluid below. Based on the provided data, answer the following questions:

1. What is the best interpretation for the leukocytosis?
2. What additional diagnostic tests would you recommend for classification of the type of neoplasm? 

Answers on next page