When examining a child with a fever without any specific symptoms or signs, special attention should be paid to the history of the disease. (The fact that we are dealing with “fever without local symptoms” already means that a thorough physical examination did not allow us to establish the source of the fever.)
It is important to find out if the child has seen signs indicating a preexisting chronic disease. For example, morning stiffness in the joints, which can be a symptom of rheumatoid arthritis; loss of body mass or abdominal pain, which may indicate regional enteritis; frequent respiratory infections, which may suggest cystic fibrosis or an immunodeficiency state. Any abnormal growth and development can push the diagnosis of a chronic disease.
Information about dealing with sick people, traveling, contact with pets and other animals helps in the diagnosis of infectious causes of fever. Useful and important are data on endemic or epidemic diseases in the geographical area where the patient lives. Detailed vaccination information helps eliminate measles, rubella, and mumps.
How long does a patient have a fever? The longer a child has a fever without local symptoms, the less likely the presence of the most common infectious diseases, such as pharyngitis, otitis, pneumonia, and gastroenteritis.
Wait until the cause of the fever manifests itself.
Most children with a fever with no local symptoms suffer from common non-dangerous diseases. In many cases, the fever is resolved on its own within a few days without an accurate diagnosis. In other cases, such common non-serious diseases, such as measles, otitis media or pharyngitis, occur within 12–48 hours. While waiting for the cause of the fever to clear up, the doctor must be fairly sure that the patient does not have a serious illness.
Apart from cases when the child is very small or when acute fever has just arisen, the most dangerous conditions can be eliminated by careful collection of the history and physical examination of the patient. Bacteremia is the only important exception to this rule.
From numerous studies, it is clear that a significant percentage of cases of bacteremia in children are not clinically manifested. After the clinician has eliminated a focal infection or thermal illness by carefully collecting history and physical examination, supplemented, if necessary, with spinal puncture, chest x-rays, urinalysis, the biggest problem in deciding whether to continue monitoring and refrain from treatment is the likelihood the presence of latent bacteremia. This is a problem that every clinician can face.