Parkinsonian syndromes and differential diagnosis

Purpose of review Physicians are becoming more astute at diagnosing the various parkinsonian syndromes but in clinical practice it is still often difficult to make the correct diagnosis. This review discusses new evidence that may aid physicians in correctly identifying parkinsonian syndromes. Recent findings We will review the newest developments in the areas of clinical features, electrophysiologic tests, autonomic tests, neuropsychologic tests, imaging, and biochemical markers which may be of value in differentiating these syndromes. Summary Accurate diagnosis of the parkinsonian syndromes has important implications for patients, in terms of both prognosis and management. Investigations reported during the last year provide new insight into the distinguishing features of these syndromes and may help clinicians and researchers define these disorders more precisely.