Presumed Dapsone-induced Drug Hypersensitivity Syndrome Causing Reversible Hypersensitivity Myocarditis and Thyrotoxicosis

Abstract

Introduction: A 22-year-old Malay soldier developed dapsone hypersensitivity syndrome 12 weeks after taking maloprim (dapsone 100 mg/pyrimethamine 12.5 mg) for anti-malarial prophylaxis. Clinical Picture: He presented with fever, rash, lymphadenopathy and multiple organ involvement including serositis, hepatitis and thyroiditis. Subsequently, he developed congestive heart failure with a reduction in ejection fraction on echocardiogram, and serum cardiac enzyme elevation consistent with a hypersensitivity myocarditis. Treatment: Maloprim was discontinued and he was treated with steroids, diuretics and an angiotensin-converting-enzyme inhibitor. Outcome: He has made a complete recovery with resolution of thyroiditis and a return to normal ejection fraction 10 months after admission. Conclusion: In summary, we report a case of dapsone hypersensitivity syndrome with classical symptoms of fever, rash and multi-organ involvement including a rare manifestation of myocarditis. To our knowledge, this is the first case of dapsone-related hypersensitivity myocarditis not diagnosed in a post-mortem setting. As maloprim is widely used for malaria prophylaxis, clinicians need to be aware of this unusual but potentially serious association. Key words: Anti-malarial, Exanthema, Myocardium, Thyroiditis