Eosinophilia in the tropics. Not always tropical eosinophilia

Abstract

Hypereosinophilia is a commonly encountered problem in tropical settings. Higher rates of parasitic infestations contribute to its prevalence in these areas. As a result, the diagnosis of hypereosinophilia due to other etiologies may be missed in this scenario due to a variety of factors including lack of awareness of these rare entities. This may result in unnecessary treatment with antihelminthic drugs. Delays in treatment may lead to the development of unacceptable end organ damage. In this series of 28 patients with unexplained hypereosinophilia only 5 (18%) met criteria for tropical pulmonary eosinophilia. Despite the use of antihelminths and microfilaricides in 24 patients, only 4 responded to this therapy. Thrombosis in conjugation with eosinophilic vasculitis was seen in 3 patients that responded to immunosuppressive therapy. The recognition of these less common conditions associated with hypereosinophilia is necessary for tropical physicians so that potentially life-saving therapy is not delayed in favour of empiric antiparasitic medications.

Keywords

• Eosinophilia
• Hypereosinophilic syndrome
• Tropical Eosinophilia
• Thrombosis