TABLE 94.10 EVALUATION OF A CHILD WITH SUSPECTED ENCEPHALITIS OR MENINGOENCEPHALITIS All suspected cases CSF Cell count and differential, protein/glucose, bacterial culture, HSV PCR, enteroviral PCR Consider holding CSF in the laboratory for additional diagnostic studies (see below) Serum CBC, chemistries, blood cultures, EBV/CMV serologies, HIV, HSV PCR, Bartonella serologies, Mycoplasma serologies Other Enteroviral PCR (respiratory, stool), PCR of respiratory specimens Specific risk factor or features Tuberculosis risk Should be suspected in any child with CSF pleocytosis and a high CSF protein and/or low factors CSF glucose: chest radiograph (abnormal in approximately 90% of children with tuberculosis meningitis; tuberculin skin test; interferon gamma release assay; gastric aspirate or sputum for acid-fast culture; CSF PCR for Mycobacterium tuberculosis Immunocompromised Acid-fast culture for tuberculosis, cryptococcal antigen (serum, CSF), human herpesvirus and 7, JC virus, Toxoplasma serum IgG; cultures for Listeria monocytogenes, VZV PCR, histoplasmosis serologies/urinary antigen Sexually active Summer/fall Winter RPR/VDRL for syphilis West Nile IgM (CSF, serum), Arboviral panel (CSF, serum), and serologies for other geographically appropriate arboviruses (e.g., St Louis, La Crosse, and the equine encephalitides) Serologies for Rickettsia rickettsii (Rocky Mountain spotted fever) and ehrlichiosis as well as Borrelia burgdorferi (Lyme disease) if in the appropriate geographic region Influenza PCR Raw or unpasteurized Toxoplasma IgG, serologies for Coxiella, culture for Listeria monocytogenes, evaluation food products for Gnanthostoma if history of travel to Southeast Asia or Latin America Animal exposures Rabies (bites from unimmunized dogs/cats or contact with bats or wild carnivores), Bartonella (cat scratches or bites from cat fleas), LCMV (exposure to rodent urine or feces) Ticks Insect contact Swimming in brackish or stagnant water Travel history Serologies or PCR for Rickettsia rickettsii, Ehrlichia chaffeensis, Anaplasma, Borrelia burgdorferi Serologies for equine encephalitides, St Louis encephalitis, Japanese encephalitis, West Nile virus, La Crosse virus and smear for malaria (if appropriate travel histories) for mosquito contact; Bartonella bacilliformis serologies (sandflies); trypanosomiasis serologies (tsetse flies) Wet mount for Naegleria fowleri Vesicular rash Serologies for fungal infections endemic in certain regions; consider early consultation with an infectious diseases specialist Infections more common outside industrialized nations are discussed in the section on Infections in Returned Travelers PCR of lesion for HSV, VZV Diarrhea and seizure CSF eosinophilia Stool for bacterial culture (Shigella, E coli ) and for rotavirus PCR Baylisascaris (raccoon roundworm) serologies CSF, cerebrospinal fluid; HSV, herpes simplex virus; PCR, polymerase chain reaction; CBC, complete blood count; EBV, Epstein–Barr virus; CMV, cytomegalovirus; HIV, human immunodeficiency virus; VZV, varicella zoster virus; RPR, rapid plasma reagin; VDRL, venereal disease research laboratory; LCMV, lymphocytic choriomeningitis virus From Tunkel AR, Glaser CA, Bloch KC, et al The management of encephalitis: clinical practice guidelines by the Infectious Diseases Society of America Clin Infect Dis 2008;47:303–327, by permission of the Oxford University Press