[Clinical-hematological demonstrations: aplastic anemia, acute leukemias, polyneuropathy in Waldenstrom's disease, acute porphyria].

Some cases are reviewed involving hematological diseases caused by exogenously or endogenously induced toxicity. First, 3 cases of aplastic anemia (chlorpromazine, chloramphenicol and probably autoantibodytypes) are discussed. The known aplastic anemia inducing agents are the chloro-hydrocarbon rings (chloramphenicol, hexachlorcyclohexane, chlorpromazine, chlorpropamide and aliphatic potassium perchlorate) as well as phenylbutazone, sulfonamides, benzol, gold, certain antiepileptic drugs and compounds which contain arsenic or bismuth. Isolated erythroblastophthisis is an autoimmune disease and is mainly observed in young people. It is stressed that cases with aplastic anemia generally exhibit considerable immunosuppression. Therefore, gamma-globulins should be given when infection is observed in these cases. In cases refractory to 2-3 years of conventional treatment (steroids, especially androgens), splenectomy is a useful alternative. Five cases of acute leukemia (4 AML and one ALL) point up the considerable advances in the treatment of this group of diseases. Caution should be exercised in interpreting a remission as a cure, since in one of our cases a remission of 12 1/2 years was followed by a lethal relapse.-A case of Waldenström's disease with severe polyneuropathy is described which was associated with severe "neuritic defects" related to inclusions of paramyloid material in the nervous tissue.-In a case of acute porphyria complicated by paraplegia an impressive remission was achieved by forced diuresis with furosemide and sorbitol combined with intensive i.v. glucose therapy (reduction of delta-aminolevulic acid production.