[Clinical profile and course of paroxysmal nocturnal hemoglobinuria]

To evaluate the clinical characteristics, laboratory findings, course, treatment and survival of a series of patients with PNH.

The clinical records of 21 patients diagnosed of PNH in the La Fe University Hospital between 1970 and July 1991 were revised. Positivity to Ham's and sucrose tests was the major diagnostic criterion. Haemolysis was studied by means of reticulocyte count, unconjugated bilirubin, LDH levels, haptoglobin, serum iron, and haemosiderinuria. The survival analysis was performed in accordance with Kaplan and Meier.

The median age in the group was 38 years (range: 18-72 years) and the M/F ratio was 11/10. The commonest symptoms at onset were weakness (76%), dark urine (47%), jaundice (33%), and purpura (24%). All the patients had anaemia, six of them (28%) presenting with aplastic anaemia. The complications most frequently seen included thrombosis (documented in 7 cases, clinically suspected in 6 others), infection (6 cases) and haemorrhage (6 cases). One patient developed aplastic anaemia after 16 years of follow-up, and another one had AML. None of the patients with PNH-associated aplastic anaemia developed thrombosis. The incidence of severe cytopenia was: Hb < 80 g/L, 62%; platelet count < or = 20 x 10(9)/L, 29%, and white cell count < or = 2 x 10(9)/L, 14%. The haemolysis-related findings were as follows: unconjugated hyperbilirubinemia, 100%; haemosiderinuria, 87%; decreased haptoglobin, 80%. Transfusion support consisted of washed red cells (total amount, 1,684 units) and platelets (137 units). A female patient with anticoagulant therapy developed haemolysis after non-isogroup plasma transfusion. Five patients required no transfusions. One patient was subjected to splenectomy and other underwent a successful bone-marrow transplant. The cause of death was related to PNH in three of the five patients who had died when this study was finished (mesenteric thrombosis, subcapsular haematoma of the liver and AML). The actuarial survival at 10 years was 68%.

1) The incidence of PNH is very low in our experience, excessive delay in diagnosis being the rule, as in other reported series. 2) Early anti-thrombotic treatment should be carried out in PNH whenever severe thrombocytopenia is not associated. 3) Allogeneic BMT is the only curative treatment.