The syndrome of meningeal leukemia is one of the major complications of acute leukemia.1,2The manifestations of the clinical syndrome include headache, nausea, vomiting, eye signs, cranial nerve palsies, and lethargy, and may be associated with increased intracranial pressure. The observation that cerebrospinal fluid (CSF) pleocytosis is almost always associated with the clinical syndrome has shifted the emphasis in the criteria for diagnosis from dependence on clinical signs and symptoms to a greater reliance on laboratory findings.3,4More recent studies further demonstrate that the CSF pleocytosis may precede the symptoms. In the review of cases reported by Nies et al,3the diagnosis of meningeal leukemia was said to be established by the presence of ten or more mononuclear cells per cubic millimeter in the spinal fluid. Judged by this criterion, of 38 cases of meningeal leukemia, 14 had no presenting signs or symptoms at the time of