Pseudocystic cryptococcal meningitis complicated by transient periaqueductal obstruction in a child with HIV infection

True aqueductal tumors: a unique entity

BACKGROUND

Pure aqueductal tumors (ATs) differ from pineal region and tectal/tegmental tumors in that they are epicentered within the aqueduct. Nevertheless, these tumors are rarely described as a separate type of tumor, and are often grouped with other lesions located in the same vicinity. The present multicenter study focuses on our experience treating patients with pure ATs.

METHODS

Data from three large tertiary centers was collected retrospectively, including presenting symptoms, treatment paradigm, surgical approaches, pathology, and outcome.

RESULTS

Between 1999 and 2013, 16 patients with AT were diagnosed and treated at the three tertiary centers. Ages at presentation ranged from 5.5 to 57 years. Thirteen patients presented with hydrocephalus-related symptoms, and two were identified incidentally. Thirteen patients underwent an endoscopic third ventriculostomy, and two of these underwent a simultaneous endoscopic biopsy (one grade II ependymoma, one non-specified low-grade glioma). Two others underwent shunt placement. Three patients underwent resection due to tumor progression. Pathologies included glioblastoma multiforme, glioneural tumor, and ependymoma grade II. All non-resected tumors remained stable or grew only minimally.

CONCLUSIONS

ATs are a rare entities that usually present with obstructive hydrocephalus. Treatment includes primarily cerebrospinal fluid drainage (preferably via an endoscopic third ventriculostomy). Simultaneous endoscopic biopsy may be done in selected cases. Tumor resection should be reserved for growing tumors; the trans-fourth ventricular or trans-choroidal approaches are probably safer than other approaches used to reach the tectal region.

Cryptococcosis in nonhuman immunodeficiency virus-infected children

Between 1991-2006, nine patients below age 18 years, with a microbiologic documentation of Cryptococcus neoformans infection and no evidence of human immunodeficiency virus infection, were identified and treated at Chang Gung Children's Hospital. All exhibited central nervous system involvement. Seven patients were female (age range, 9-16 years; mean age, 13.7 years). Five patients (56%) manifested underlying diseases and were receiving either steroid or immunosuppressant treatment at time of disease onset. Eight patients presented with meningitis. Headache, vomiting, and focal neurologic signs were the most common presentations. Protein and sugar levels in cerebrospinal fluid were within normal range in seven cases, whereas India ink smear and cryptococcal antigen testing were positive in 87% (7/8) and 78% (7/9) of patients, respectively. With prompt antifungal therapy, all survived, but one presented the sequel of blindness. Cryptococcosis is uncommon in the nonhuman immunodeficiency virus-infected pediatric population. Clinicians should take into account a diagnosis of central nervous system cryptococcosis when children present with prolonged headache, vomiting, and focal neurologic signs. Indian ink stain and cryptococcal antigen testing of cerebrospinal fluid should be performed.

Central nervous system manifestations of HIV infection in children

Vertically transmitted HIV infection is a major problem in the developing world due to the poor availability of antiretroviral agents to pregnant women. HIV is a neurotrophic virus and causes devastating neurological insults to the immature brain. The effects of the virus are further compounded by the opportunistic infections and neoplasms that occur as a result of the associated immune suppression. This review focuses on the imaging features of HIV infection and its complications in the central nervous system.

Cryptococcal neuroradiological lesions correlate with severity during cryptococcal meningoencephalitis in HIV-positive patients in the HAART era

Cryptococcal meningoencephalitis has an overall global mortality rate of 20% in AIDS patients despite antifungals. There is a need for additional means of precise assessment of disease severity. We thus studied the radiological brain images available from 62 HIV-positive patients with cryptococcocal meningoencephalitis to analyse the brain lesions associated with cryptococcosis in relationship with disease severity, and the respective diagnostic contribution of magnetic resonance (MR) versus computed tomography (CT).

In this retrospective multicenter analysis, two neuroradiologists blindly reviewed the brain imaging. Prospectively acquired clinical and mycological data were available at baseline and during follow-up. Baseline images were abnormal on 92% of the MR scans contrasting with 53% of the CT scans. MR/CT cryptococcosis-related lesions included mass(es) (21%/9%), dilated perivascular spaces (46%/5%) and pseudocysts (8%/4%). The presence compared to absence of cryptococcosis-related lesions was significantly associated with high serum (78% vs. 42%, p = 0.008) and CSF (81% vs. 50%, p = 0.024) antigen titers, independently of neurological abnormalities. MR detected significantly more cryptococcosis-related lesions than CT for 17 patients who had had both investigations (76% vs. 24%, p = 0.005). In conclusion, MR appears more effective than CT for the evaluation of AIDS-associated cerebral cryptococcosis. Furthermore, brain imaging is an effective tool to assess the initial disease severity in this setting. Given this, we suggest that investigation for cryptococcosis-related lesions is merited, even in the absence of neurological abnormality, if a high fungal burden is suspected on the basis of high serum and/or CSF antigen titers.

Transient acute obstructive hydrocephalus of unknown origin in a 13-month-old infant

We report on a case of a 13-month-old female infant who was admitted to our department with the chief complaints of drowsiness and vomiting. A history of an unspecified viral infection was reported. Clinical examination was negative for focal neurological signs or signs of central nervous system infection. Initial CT scan revealed obstructive hydrocephalus, and shunting was scheduled. Dexamethasone treatment was started. Eight hours after admission the child almost restored his baseline mental status and the operation was postponed. The dexamethasone treatment was discontinued 3 days later. Follow up CT and MRI scans were normal. We discuss the case and the possible causes of transient hydrocephalus in children.