Infantile B-cell acute lymphoblastic leukaemia with the highest recorded count of white blood cells in the literature: case report and literature review

Abstract

Introduction: Infantile leukaemia is an uncommon haematological cancer that manifests within the first year of life. This malignancy is highly aggressive and possesses distinctive immunophenotypic, cytogenetic, and molecular attributes. It can originate from either myeloid or lymphoid cells. It often exhibits a higher incidence among females. Case presentation: A 1-month-old male infant, initially seemingly healthy, presented with irritability and feeding difficulties. Born without complications, routine neonatal assessments appeared normal, and physical examination revealed no abnormalities. However, laboratory tests indicated an extremely high white blood cell count, low platelets, and elevated haemoglobin. Further examinations showed a white blood cell count of 1450 × 106/l with a blood film revealing significant leukocytosis dominated by blast cells. Abdominal ultrasound confirmed hepatosplenomegaly which was not present during pregnancy. Subsequent bone marrow analysis and flow cytometry established a diagnosis of B-cell acute lymphoblastic leukaemia (B-ALL). Clinical discussion: It is rare for infantile ALL to manifest within the first month after birth. In most cases, the diagnosis is established before birth. When characteristic signs such as hepatosplenomegaly, leukaemia cutis, or infiltrative involvement of the extramedullary and central nervous systems are present, postnatal diagnoses are relatively straightforward. However, there are instances where children present with non-specific and ambiguous symptoms that resemble other medical conditions. Conclusion: This case underscores the importance of paediatricians being vigilant and attuned to the subtle indicators that differentiate common illnesses from serious conditions such as infantile ALL.