Rationale: Facial paralysis as the initial clinical presentation of infant leukemia (IL) is rare, and the rate of its misdiagnosis is high. Identifying the clinical characteristics of IL with facial paralysis as the initial symptom is necessary to improve the understanding of the causes of facial paralysis and IL.
Patient concerns: A 10-month-old infant had facial paralysis and recurrent fever. He was misdiagnosed as having bacterial meningitis for >2 months.
Diagnoses: The infant was diagnosed as having acute monocytic leukemia (M5) with central infiltration based on examinations of the bone marrow and cerebrospinal fluid by flow cytometry.
Interventions: Before the diagnosis of leukemia, the patient was given meropenem, ceftriaxone, vancomycin, and ampicillin successively for anti-infective treatment for 2 months, and dexamethasone for several days. But he gave up further treatment after confirmed diagnosis.
Outcomes: Our patient discontinued treatment and discharged. From literature review, there were 6 cases (including this case) of IL with facial paralysis as the initial symptom. 80% of patients were misdiagnosis and treated with a corticosteroid in the early stage, and the mortality was 33.3%.
Lessons: The clinical symptoms of IL with facial paralysis are not typical, with a high rate of misdiagnosis. When the cause of facial paralysis is unknown or the advance treatment effect is poor, tumor diseases should be considered. Corticosteroids should be carefully administered to children with facial paralysis.