Objectives: Patients with mild hereditary spherocytosis (HS), i.e. with haemolysis without anaemia. have an increased risk of gallstone formation, erythroid aplasia and haemolytic crisis. Since the effect of prophylactic splenectomy on life expectancy has not been established, we conducted a decision analysis comparing prophylactic splenectomy and cholecystectomy with no surgery.
Design: The available data on surgery and disease outcomes were modelled to estimate the effects of the different interventions on the quality-adjusted life expectancy. The early phase outcomes depicted surgery-related mortality and incorporated compliance and the adverse effects of prophylaxis against post splenectomy infections. The late phase outcomes were framed by a Markov cohort analysis.
Results: For patients without gallstones, surgery was of no benefit. For those with gallstones the preferred strategies were found to be splenectomy and cholecystectomy before the age of 39 when asymptomatic, and before 52 when accompanied by occasional biliary colic. Cholecystectomy alone proved to be the preferred strategy in older patients with occasional biliary colic. For patients of up to 52 years of age and candidates for cholecystectomy because of recurrent biliary colic, the best strategy was to combine this procedure with splenectomy. Sensitivity analysis showed that the results were sensitive to the incidence of post cholecystectomy syndrome. Most remarkably an extreme sensitivity to compliance with post splenectomy infection prophylaxis was demonstrated.
Conclusions: Our model suggested that combined prophylactic splenectomy and cholecystectomy provide a substantial gain in quality-adjusted life expectancy for young patients and adults with mild HS and gallstones.