Early diagnosis is important in initiating treatment within 24 h of symptom onset, which is crucial for survival. Aspiration of a bubo or sputum and gram stain analysis can provide a rapid bedside diagnosis. Definite diagnosis is made by culture; the cultures are often negative for 24 h, but turn positive at 48 h. The anti-Y. pestis titer rises fourfold or greater. Blood count shows a leukocytosis with left shift, and bilirubin and aminotransferase levels are elevated. The central nervous system (CNS) manifestations with meningeal involvement can complicate any of the forms and occur in approximately 6 to 7% of plague cases. Cerebrospinal fluid analysis reveals a neutrophilic pleocytosis [43] .