THE BLOOD AND THE BLOOD-FORMING ORGANS. 391 



somewhat characteristic condition is produced by hyperplasia, often fol- 

 lowed by ulceration, of the lymph -nodules of the gastro-intestinal tract 

 (intestinal type). The hyperplastic lymph-nodes may be isolated, or 

 they may be joined to form large lobulated masses. The enlarged lymph - 

 nodules may in the intestine project far into the lumen in spheroidal or 

 polypoid form, and are sometimes dark in color as the result of the de- 

 composition of hemoglobin of extravasated blood in the congested 

 mucous membrane covering the nodules. Hyperplasia of the thymus has 

 been described in association with the lesions of the lymph-nodes. ' A 

 distinct sub -variety is that which terminates in leukaemia. In general 

 any of the lymph-nodes or collections of lymphoid tissue may be in- 

 volved, and nearly every region has been a site of origin for the new 

 growths of lymphoid tissue, so that a great variety of combinations may 

 be seen. 



The leucocytes in the blood may be slightly increased or diminished, 

 and in either case the mououuclear forms are usually in excess. Myelo- 

 cytes have been observed in moderate percentage, but never in such pro- 

 portions as in leukaemia. 2 



AN-ffiMIA INFANTTJM PSEUDO-LEUK^JMICA (von Jaksch). 



This is a somewhat peculiar form of anaemia occurring in children, 

 and characterized by progressive anaemia, by a considerable increase of 

 leucocytes, by enlargement of the spleen and liver, and often by hyper- 

 plasia of the lymph- nodes. 



By some authorities it is regarded as an early stage of leukaemia, by 

 others as a form of secondary anaemia following rachitis, tuberculosis, or 

 syphilis. 



The histological changes in the blood-forming organs are, so far as is 

 known, very similar to, but less pronounced than, those of leukaemia. 



1 Brigidio and Piccoli, Ziegler's Beitr. z. path. Anat., Bd. xvi., p. 388. 

 F. Ooppert, Vivch. Arch., Bd. cxliv.. 1896. Supplementheft. p. 1. 

 "Consult Monte and Benjgrun, "Die chronische Anaemic d. Kindesalters," Leipsic, 

 1892. 



