ABSTRACT
The height and duration of fever are important. Rigors (chills or shivering, often uncontrollable and lasting for 20-30 minutes) are highly signifi cant, and so is a documented temperature over 37.5 °C taken with a reliable oral thermometer. Drenching sweats are also highly signifi cant. Rigors generally indicate serious bacterial infections (lobar pneumonia, endocarditis, septicaemia, cholangitis, pyelonephritis, etc.)
or malaria. An oral temperature >39 °C has the same signifi cance as rigors. Rigors generally do not occur in mild viral infections (e.g. those caused by respiratory viruses, Epstein-Barr virus (EBV), hepatitis), malignancy, connective tissue diseases, tuberculosis and other chronic infections. Table 21.1 lists the features that distinguish rigors from a grand mal convulsion.
