Introduction
A reactive leukocytosis, with a significant increase in early neutrophil precursors, exceeding 50,000/mm3 is referred to as a leukemoid reaction[1]. The major causes of a leukemoid reaction include paraneoplastic manifestation of several cancers such as lung, gastrointestinal, genitourinary, ovarian, head and neck cancers and hepatocellular carcinoma[2,3], severe infections, intoxications, corticosteroid administration, severe haemorrhage and acute haemolysis[4,5]. The differential diagnosis of a leukemoid reaction in patients is often a true challenge. Diagnostic work-up must be able to differentiate underlying causes from acute and chronic leukaemia[6]. These reactions have been attributed to increased cytokine production[7]. The cytokines implicated in this process include granulocyte-macrophage colony-stimulating factor (CSF), granulocyte-CSF (G-CSF), interleukin-3 (IL-3) and IL-6[8,9]. Most leukemoid reactions are seen in senior patients and are associated with a poor prognosis[10]. Here, the case of a young woman who had severe clinical symptoms, a leukemoid reaction after major surgery, and who progressed to a good outcome in the end, is presented.