Nonleukemic Lymphocytosis 149 



Table 11-1. Conditions Accompanied In Lymphocytosis 

 (Pathologic, Nonleukemic) 



1. Constant or diagnostic 



A. Lymphocytes of the "virocyte" type 



1. Infectious mononucleosis 



2. Acute viral hepatitis 



3. Viral pneumonitis 

 1. Herpes zoster 



5. Herpes simplex 



(i. Roseola infantum 



7. Upper respiratory infections (viral) 



B. Lymphocytosis, normal morphology 



1. Infectious lymphocytosis 



2. Mumps 



3. Chicken pox 



I. German measles 

 5. Pertussis 



II. Transient or inconstant 



A. Congenital syphilis 



B. Secondary stage of syphilis 



C. Scarlet fever 



D. Brucellosis 



E. Typhoid fever 



F. Hyperthyroidism 



G. Myasthenia gravis 

 H. Hypopituitarism 



I. Chronic tuberculosis 



J. Chronic exposure to ionizing radiation 



K. Others 



itself, it is often helpful in corroborating the clinical diagnosis. At times 

 the lymphocytosis is present in the prodromal stage before a clinical diag- 

 nosis is possible. 



This then leaves Subgroup I-A. If a grouping of this sort is justified, 

 it raises some intriguing points. The common denominator of this group 

 is the presence in the peripheral blood of mononuclear cells which are 

 almost certainly of lymphocytic origin. These cells do not fit the usual 

 descriptions of either normal or of leukemic lymphocytes. For want of a 

 better term, they have often been referred to as "atypical lymphocytes." 

 Attention was drawn to these cells as soon as hematologists began examin- 

 ing the peripheral blood. For example, Turk in l')()7 ls recorded a case in 

 which the peripheral blood contained atypical cells thought to be blasts of 

 acute leukemia but remarkable in that the patient recovered. It has been 

 suggested that this is one of the earliest reported cases of what Ave now 

 call infectious mononucleosis, or at least one of the earliest cases in which 

 the peripheral blood was studied. Turk's description of an atypical cell hav- 

 ing- cytoplasmic features of a plasma cell and a somewhat immature nucleus 



