Persistent gross splenomegaly in Nigerian patients with sickle cell anaemia: relationship to malaria.

Serum IgM levels, hepatic histopathology, and response to prolonged proguanil treatment were investigated in 15 patients with sickle cell anaemia (SS), aged 8-15 years, with persistent gross splenomegaly (PGS). They were compared with age- and sex-matched SS patients without splenomegaly and with AA controls. The mean +/- SD serum IgM levels were 249.7 (75) mg/100 ml in the SS patients with PGS, 157.6(57.3) mg/100 ml in the SS patients without splenomegaly, and 146.2(48.9) mg/100 ml in the AA controls. The differences between these mean values were statistically significant (P less than 0.05). Hepatic histopathology in 11 of these patients showed moderate to severe sinusoidal dilatation and portal lymphocytic infiltration. Of the 13 patients that were followed on daily proguanil therapy, 10 showed remarkable reduction in splenic size within 6 months. The mean splenic size diminished by 13.8(3.2) cm to 5.6(5.3) cm over the period. The difference was statistically significant (P less than 0.01). This study has confirmed the previous belief that malaria plays a role in the aetiopathogenesis of persistent splenomegaly in sickle cell patients in a fashion similar to, but not quite the same as in, tropical splenomegaly syndrome (TSS). It also underscores the need for malaria chemoprophylaxis in these patients.