Cryptococcal meningitis: a hospital-based study

Abstract

OBJECTIVE: Cryptococcus meningitis (CM) is an uncommon CNS infection. This study aimed to find out the clinical and radiological characteristics of CM patients. METHODS: Records of CM patients diagnosed and treated in Queen Mary Hospital during the period 1995-2008 were retrospectively studied. Cryptococcus meningitis was diagnosed by raised cryptococcal antigen titer in CSF with exclusion of other causes of meningitis. Patients who died from CM or who had modified Barthel Index (mBI) <12 at 6 months after initiation of anti-fugal therapy was classified as having poor clinical outcome. RESULTS: Twenty-one CM patients were identified, 11 were male. Fourteen (67%) patients had medical comorbidities at presentation and were immunocompromised: six (29%) had autoimmune diseases such as SLE on immunosuppressants, four (19%) were HIV carriers, two (10%) had chronic rheumatic heart disease, and two had renal transplant on immunosuppressants. The mean age of onset was 48 years (SD, 15). The mean duration of presenting symptoms was 33 days (SD, 37 days). Presenting symptoms included headache (76%), fever (71%), neurological deficits (43%, including incoordination, limb weakness, diplopia, blurring of vision), confusion (33%), lethargy/dizziness (28%), nausea/vomiting (28%), neck pain (24%), decreased GC (5%), personality change (5%) and incontinence (5%). The most common clinical signs at presentation were neck stiffness (33%) and cranial nerves palsy (24%). The mean opening pressure on LP was 21 cm water (range, 3-55; SD, 13), mean CSF cell count 61/μL (range, 2-290/μL; SD, 99/μL), mean CSF glucose 2.2 mmol/L (range, 0.9-3.8; SD, 0.9) and mean CSF protein 1.4 g/L (range, 0.5-6; SD, 1.4). Initial neuroimaging revealed abnormalities in seven (33%) patients, including leptomeningeal enhancement (1), calcification from previous inflammation (1), hydrocephalus (1), cerebral oedema (1), and cerebral infarctions (3). Standard anti-fungal medications was started immediately once CM was diagnosed. Five (24%) patients succumbed from CM despite active treatment, including three HIV carriers, one ESRF patient post-renal transplantation on immunosuppressants, and an 83-year-old man with good past health. Ten (48%) patients had good recovery with mBI at 6 months >90, and only one of the 16 survivors had poor outcome with mBI at 6 months <12. CONCLUSION: Cryptococcus meningitis is a serious CNS infection predominantly affecting immunocompromised patients with a mortality rate of 24%. HIV infection, immunosuppression for organ transplantation and advanced age might be risk factors for mortality from CM. Most survivors had satisfactory functional recovery with only mild or minimal neurological disability.