SERUM DISEASE 575 



gested in almost any variety of serum sickness. It is differentiated 

 from measles by the fact that Koplik's spots are absent, there is no pro- 

 dromal rise in temperature, the papules are not elevated above the skin 

 as much as in measles, and that the eruption frequently starts from the 

 site of injection, instead of on the face. 



3. Scarlatiniform Rashes. This type of rash occasionally occurs, 

 and may bear so close a resemblance to true scarlet fever as to be indis- 

 tinguishable from it. The eruption usually appears early, that is, in 

 from the first to the sixth day after injection, and may vary from a 

 uniform erythema which first appears about the site of injection, to a true 

 punctate scarlatinal rash. The differentiation of these rashes from the 

 true scarlet-fever eruption is one of the greatest sources of trouble in 

 hospital practice, especially when they develop in the diphtheria wards, 

 where occasional cases of true scarlet fever are always likely to appear 

 from time to time. The absence of the following symptoms, or their 

 occurrence only in mild degree, would favor a diagnosis of serum disease : 

 Fever, or, at least, the presence of but a mild pyrexia, the vomiting, the 

 typically furred tongue, the angina, or at least but a mild throat involve- 

 ment, and the leukocytic inclusion bodies all forming the symptom- 

 complex of true scarlatina. In many instances, however, it is necessary 

 to isolate the patient, when speedy recovery, absence of complications, 

 and less definite desquamation, which does not involve the palms and 

 soles, indicate that the patient was suffering from serum disease and not 

 from scarlet fever. 



Severe Serum Disease. The severer forms of serum disease, 

 characterized by sudden onset, often within a few minutes after the 

 injection of serum, extreme dyspnea, prostration, and death are, 

 fortunately, rare, about 30 cases in all being now on record. While 

 physicians are justified in exercising care and caution in the administra- 

 tion of serum, there are no absolute contraindications to its use except 

 status lymphaticus and those instances where the person is known to be 

 hypersensitive to horse serum. Occasionally sudden and severe dyspnea 

 and prostration accompany an immediate reaction when a reinjection 

 of serum is given within a few weeks after the first. Persons suffering 

 with asthma are also bad risks, especially since the effects of serum 

 disease upon the bronchial mucosa are likely to aggravate the already 

 existing condition. This subject will be discussed in greater detail 

 under the head of Contraindications to Passive Immunization in Chap- 

 ter XXX. 



