Spurious Hyperleukocytosis

Hyperleukocytosis is an oncological emergency but is extremely rare in non-malignant conditions. Nucleated RBCs give rise to spuriously high total leucocyte count and cause clinical dilemma. Thalassemia major patients are known to have leucocytosis even after correction for nucleated RBCs. We report a case of undiagnosed Thalassemia major in a 4 month old infant with total leucocyte count higher than one lakh and referred as a case of leukemia. Nucleated RBCs in peripheral blood points to underlying systemic illness and the investigation for the same will avoid delay in diagnosis.