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the return of ill health after an apparent or partial recovery



a new exacerbation of a disease during remission after an apparent recovery. In the case of a latent chronic infection, for example, brucellosis, pneumonia, and erysipelas, a relapse may be caused by inadequate immunity, chilling, or the supervention of a secondary infection. It may also be caused by a faulty diet, for example, with colitis, or by the cyclical nature of the disease itself (malaria, relapsing fever). The pathogenic microflora of the body is usually activated as a result of a relapse. A repeated infection caused by the same microorganisms is called a reinfection.

The pathogenesis of a relapse of a noninfectious disease is caused by shock, for example, with eczema, by vascular disorders, by regular malignant growth, and by inadequate treatment, for example, by the incomplete removal of a tumor. The pathogenesis of a relapse is sometimes unknown, for example, with familial Mediterranean fever and schizophrenia.

The clinical symptoms of a relapse may resemble or differ from the onset of a disease as a result of both the nature of the disease and the prescribed treatment. A relapse is sometimes more severe than the first attack of a disease and is more difficult to treat, as in the case of a relapse of acute leukemia. A relapse may be accompanied by complications, for example, intestinal bleeding in typhoid. Relapses are common to some diseases, for example, chronic dysentery. Treatment and preventive methods for relapses are usually the same as for the original disease.


References in classic literature ?
I think it probable," said the Doctor, breaking silence with an effort, "that the relapse you have described, my dear friend, was not quite unforeseen by its subject.
In the first place, my hand would relapse into its wicked old caricaturing habits.
The news of my father's death brought on a relapse.
At any small surprise of the senses he would start visibly and sometimes turn pale, then relapse into a melancholy apathy deeper than before.
In the meantime, after this one relapse at Benicia, I went on with my abstemiousness, primarily because I didn't want to drink.
The first of these communications brought intelligence of a serious relapse in Mr.
Now there is no one circumstance in which the distempers of the mind bear a more exact analogy to those which are called bodily, than that aptness which both have to a relapse.
When he judged himself--that was his supreme moment; let not the exalted one relapse again into his low estate!
More than once the agitation into which these reflections threw me made my friends dread a dangerous relapse.
Serjeant Buzfuz paused in this place, to see whether the jury smiled at his joke; but as nobody took it but the greengrocer, whose sensitiveness on the subject was very probably occasioned by his having subjected a chaise-cart to the process in question on that identical morning, the learned Serjeant considered it advisable to undergo a slight relapse into the dismals before he concluded.
I do not know whether he is well off now, and precisely what Marfa Petrovna left him; this will be known to me within a very short period; but no doubt here in Petersburg, if he has any pecuniary resources, he will relapse at once into his old ways.
Beth kept on, with only slight relapses into idleness or grieving.