LEUKEMIA ' 171 



(a) Lymphatic leukemia is characterized by enlargement 

 of the lymph glands and the presence of small, uninuclear 

 lymphocytes in the blood. 



(b) In myeloid leukemia there is an enormous enlargement 

 of the spleen, the follicles of which are hyperplastic (lineal 

 leukemia). In the blood large numbers of neutrophile poly- 

 nuclear leukocytes occur even as many as from one to five 

 hundred thousand in place of eight thousand per c.mm. The 

 erythrocytes are diminished in number and their form is 

 changed. In the myelogenic leukemia the red bone-marrow 

 is hyperplastic, infiltrated and often resembles pus. In the 

 blood there is an increase of the large uninuclear myelocytes. 

 In both forms of leukemia anemia is present. 



Symptoms. — The development of leukemia is insidious. 

 Generally the patient shows lack of energy, sweats easy, 

 shows capricious appetite, heart palpitation and rapid, 

 small pulse. The mucous membranes become pale even to 

 pure white in color. The patient grows thin, eventually 

 emaciates and from time to time edematous swellings appear 

 on different portions of the body. In the lymphatic form, 

 which is commoner in animals than in man, swelling of the 

 lymph glands appears symmetrically on both sides of the 

 body. The swellings are firm, round and non-sensitive. The 

 lymph glands of the maxillary space, the prepectoral and 

 precrural lymph glands are commonly involved. In some 

 cases the enlargement of lymph glands is so great as to inter- 

 r fere with the function of organs. Therefore dyspnea, roaring, 

 lameness, etc., result. Occasionally an enlargement of internal 

 lymph glands (mediastinal, sublumbar) leads to severe 

 dyspnea, fecal retention and the like. 



In the lineal form the spleen is enormously enlarged. In 

 the horse it may be palpated through the rectum and in small 

 animals occasionally a distention of the left side of the 

 abdomen designates the enlarged spleen. The liver is also 

 greatly enlarged, in one case in the horse weighing nearly fifty 

 pounds. The blood is pale, stains less intensively and coagu- 

 lates very slowly. Under the microscope the number of leu- 

 kocytes is greatly increased. In some instances there may be 

 as many white as red corpuscles in the microscopic field. 



Digitized by Microsoft® 



