The correlation of the clinical and postmortem findings shows that there is no close relationship between the syndrome of polyarteritis nodosa and the allergic states, that pain is the most common symptom, that congestive heart failure is the common cause of death. There is no consistent relationship of the symptomatology referable to the gastrointestinal, central nervous, and pulmonary systems to the pathologic lesions found. Above all, it is to be noted that although hypertension is one of the most frequent signs of polyarteritis, it may develop very late. Therefore, the rejection of this diagnosis because of the absence of hypertension will lead to error, as may the absence of eosinophilia and subcutaneous nodules.