The practitioner may be faced with the patient who has recurrent paroxysms of prostration associated with low grade fever and night sweats; the pediatrician may see a child who has attacks of jaundice, growing pains and an enlarged heart; the surgeon may have an operative case whose wound refuses to close or whose abscess continues to drain. While in many people presenting such pictures, the diagnosis of tuberculosis, rheumatic fever, or syphilis usually holds, in others, all the approved criteria may be negative. The patient may then be put through many elaborate laboratory procedures to no avail, whereas a simple