ACUTE OR SEVERE FORM— DIAGNOSIS 



1575 



convalescent, but anaemic and feeble. According to Monge, syste- 

 matic examination of the blood reveals the fact that a time arrives, 

 which he calls the critical period, when the leucocytes are reduced; 

 the polymorphonuclear leucocytes also diminish in numbers, and 

 the eosinophiles, which have been practically absent, reappear, and 

 a definite mononuclear increase supervenes. This critical period 

 lasts four to five days, and changes completely the blood picture. 



During the decline of the disease there is slight oligocythaemia and 

 granular red cells, while the mononuclear cells are increased to 

 50 to 60 per cent.; there is slight eosinophilia, and the haemoglobin 

 value is normal. 



The course of the disease, however, is by no means as straight- 

 forward as depicted, for at times the eruption comes out poorly, 

 and is limited in its distribution, or, having developed, may dis- 

 appear, in which cases the general symptoms, which may have 

 improved, are apt to return and cause a serious illness. 



Acute or Severe Form. — This form — Carrion's disease, sensu 

 stricto — is considered by many authorities to be a condition separate 

 from verruga, and when present in verruga to be merely a compli- 

 cation. It seems to be a fever of the enteroidea groiip. The 

 temperature becomes almost continuous, the pains and the diar- 

 rhoea severe, the urine dark and scanty, acid in reaction, with high 

 specific gravity, increased indican and urobilin, but rarely albumen, 

 and never blood. It contains something which reduces Fehling's 

 solution. According to some observers the anaemia becomes pro- 

 found, the red cells being reduced to 500,000, according to Monge, 

 nucleated red cells appearing, while death results in about two or 

 three weeks. 



Varieties.— Slight cases may pass through the whole illness 

 without fever, while more severe cases show intermittent or even 

 remittent fever. 



Complications, — The complications are numerous, and include 

 septic poisoning, malaria, tuberculosis, and syphilis. 



The observers who consider Oroya fever a separate entity from ver- 

 ruga, admit that it is not rarely complicated with the latter. 



Sequelae. — ^The usual sequelae are anaemia, dropsy, and affections 

 of the nervous s^/stem. 



Diagnosis. — ^The most important feature in the diagnosis is resi- 

 dence in one of the endemic areas, when a person complaining of 

 vague pains and illness, with distinct anaemia, with or without 

 febrile symptoms, should be regarded as most likely to be suffering 

 from the febrile or anaemic stage of verruga. The rapidity with 

 which the anaemia is developed is an important point in the 

 diagnosis, for in the severe forms of the disease the number of 

 the red cells will fall in three to four da^^s to less than 

 1,000,000 per cubic miUimetre, and even in slight cases there will 

 be a marked diminution. Concurrently in the severe forms all 

 the signs of the blood picture of pernicious anaemia will develop. 

 This anaemia imprints a typical facies upon the patient. The 

 febrile stage must be differentiated from malaria by the absence 



