Intracranial infection in cardiac transplant recipients

Infections have produced most of the deaths in the Stanford cardiac transplant program. Of the first 182 transplant recipients, 27 developed nonviral intracranial infections: meningoencephalitis/abscess in 16 patients, meningitis in 9, and rhinocerebral phycomycoses in 2. The responsible organisms included aspergillus, toxoplasma, candida, klebsiella, cryptococcus, coccidioides, listeria, mucor, and rhizopus. Characteristically, the areas of meningoencephalitis and abscesses were multiple and deep seated. Intracranial infections were invariably associated with pulmonary or disseminated infection with same organism. Computed tomographic (CT) brain scans in patients with meningoencephalitis often showed minimal, nonspecific, low-density lesions which usually did not exhibit contrast enhancement. At surgery the lesions were found to differ from typical pyogenic abscesses in that capsules were not well developed, and the aspirate consisted of necrotic fragments of edematous white matter and inflammatory cells rather than liquefied pus. Aspergillus infections of the central nervous system usually developed within the first three months after transplantation. Cases of meningitis occurred at variable times after transplantation, but approximately half appeared within 30 days after immunosuppressive therapy for treatment of rejection was increased. The prognosis for brain abscess depended on the causative organism. All patients with aspergillus infection died despite treatment with amphotericin B. The toxoplasma abscess responded to a combination of sulfadiazine and pyrimethamine. Meningitis was successfully suppressed or cured with appropriate treatment except for 1 patient with disseminated cryptococcosis.