[Rare diseases recognizable from blood smears].

The examination of peripheral blood smears is not only essential for the differential diagnostics of hematological diseases but can also provide important indications for general internal diseases, infections, hereditary diseases and poisoning. By the systematic analysis of a blood smear for alterations to thrombocytes, erythrocytes and leukocytes, a blood smear investigation can make a decisive contribution to the formulation of a diagnosis. In this way evidence of rare diseases can also be gained when taking the corresponding clinical findings into consideration.