Clinical course of dengue in patients with thalassaemia

Dengue and thalassaemia are prevalent in tropical regions. Thalassaemia patients with dengue present with atypical clinical manifestations and may experience more severe disease and complications.

To investigate the clinical manifestations and outcome in thalassaemia patients with dengue.

Medical records of thalassaemia patients aged from birth to 18 years with serologically-confirmed dengue who were admitted to Chiang Mai University Hospital, Thailand from January 2005 to December 2010 were reviewed retrospectively. Clinical presentation, laboratory results and outcome were analysed.

Twenty patients were included and their mean (SD) age was 13·6 (3·1) years. Patients were as follows: haemoglobin H (HbH)/Hb Constant Spring disease 7, HbH disease 3, HbH disease/HbE trait one, beta-thalassaemia/HbE disease 7, beta-thalassaemia/HbS disease one and unspecified thalassaemia one. Four patients had primary and the others secondary dengue. Five patients (25%) had severe dengue, three with severe liver involvement, one with a massive upper gastro-intestinal haemorrhage and one with acute interstitial nephritis, raised creatinine and seizures. Nineteen patients required red cells transfusions. All made a full recovery. Almost all patients presented with haemoglobin lower than baseline. While mean (SD) haemoglobin at baseline was 8·2 (1·6) g/dl, mean (SD) haemoglobin on admission was 6·4 (1·6) g/dl. Median maximum AST and ALT levels were 359 (range 42-5344) and 81 (12-1846) units/L, respectively.

Thalassaemia patients with dengue present with anaemia rather than haemoconcentration. Most patients have markedly increased AST levels in relation to ALT, and severe dengue, especially severe liver involvement, is common. In patients with thalassaemia, awareness of the atypical manifestations should aid early recognition of dengue.