Volume 1, Issue 2

 

The Captivating Cryptococcoma - A Mystery Lurking in the Brain

May 10, 2010

 

Cerebral cryptococcoma is a cryptococcal infection of the CNS presenting as a focal granuloma.  These intracranial lesions are uncommon in AIDS patients with cryptococcal meningitis, but when the two entities co-exist, mortality can exceed 30% even after therapy. 

A 42y/o male with no known prior medical history presented to the ER complaining of headache, neck stiffness, blurred vision, low-grade fevers, weakness, and vomiting for one month.  The headache was intermittent, throbbing, 10/10 in intensity, and localized to the occipital region.  It was relieved by over-the-counter Excedrin, and aggravated by cigarette smoking and sunlight.  The patient noted approximately four episodes of vomiting on day of admission and stated that he had been having clear emesis over the last month.  He denied recent travel, use of IV drugs, or other HIV risk factors.  In the ER, the patient’s vital signs were stable, and the physical exam, including neurologic and fundoscopic evaluation, was grossly normal.   The CT head with/without contrast on admission excluded an intracranial mass lesion.  However, the initial LP diagnosed cryptococcal neoformans meningitis and follow-up LPs identified antigen titers of 1:512.  Subsequent brain MRIs demonstrated occipital cryptococcal leptomeningitis, dilated ventricles, cryptococcoma of the right putamen, and gelatinous pseudocysts in the thalamus and basal ganglia.  Amphotericin-B and flucytosine were initiated with poor response.  After several trials, a successful regimen was established with liposomal amphotericin-B with voriconazole.  With the finding of cryptococcal meningitis, HIV testing was prompted and the patient was newly diagnosed with AIDS (CD4 count= 20).  HAART treatment was deferred due to poor oral intake and persistent nausea, despite placement of a VP-shunt for increasing intracranial pressure.  Another complication during his hospitalization was neutropenia, a poor prognostic indicator in cryptococcal meningitis.  Additionally, the patient developed severe hypokalemia secondary to amphotericin-B and consequent QT prolongation.  In spite of these obstacles, administration of the proper treatment regimen achieved good clinical response.  Furthermore, a MRI of the brain performed two months after diagnosis demonstrated dystrophic calcification in the areas around the cryptococcoma and pseudocysts of the basal ganglia, suggesting a positive treatment response.

Etiologic diagnosis is necessary since CNS tuberculoma, toxoplasmosis, and lymphoma in AIDS patients can mimic the clinical syndrome and radiographic findings of cryptococcoma.  Delay in identification can lead to inappropriate treatment, inability to address resistance to therapy, and high morbidity/mortality rates. Although cerebral cryptococcoma rarely accompanies cryptococcal meningitis in immuno-compromised patients, it is a vital differential to consider in order to prevent the potentially life-threatening outcome of this infective CNS lesion.