Cryptococcal Meningitis Simulating a Posterior Fossa Tumor

Cryptococcal meningitis, also known as Torula meningitis and yeast meningitis, is caused by an infection of Cryptococcus Neoformans (Torula Histolytica), and is the most common form of mycotic infection of the central nervous system. Since the first report of this disease by Busse in 1894. many cases have been reported in the literature. A few cases of cryptococcal meningitis have been reported ill Korea. A thirteen-years old Korean boy had severe occipital headache. mental change and decreased vision. and was admitted to Seoul National University Hospital on December 14, 1968. On neurological examination. bilateral papilledema. right 6th nerve palsy. right-sided hemiparesis and trunkal ataxia were found. Skull films showed evident suture separation along with so-called silver-beaten appearance. Carotid angiogram and ventriculogram showed a marked symmetrical. bilateral dilatation of ventricular system suggesting an obstruction of the CSF pathways in the posterior fossa. Examination of cerebrospinal fluid showed a slight pleocytosis. elevated protein and decreased sugar content. Exploring the posterior fossa, an enlarged cisterna magna and thickened basal meninges coated with yellowish necrotic debris or sediments were demonstrated. A diffuse or more localized opacity of meninges and obliteration of subarachnoid space over the cerebellar hemispheres. particularly. the portion of vallecula. were encountered. Microscopic findings was acute and chronic inflammatory changes in different stages with well encapsulated cryptococcus in loose connective tissue. On the 10th postoperative day the patient died. No amphotericin B therapy was done. Postmortem examination could't be done