IgG4-related disease: a rare but treatable cause of refractory intracranial hypertension.

Hypertrophic pachymeningitis secondary to IgG4-related disease is a rare but sometimes devastating cause of intracranial hypertension. It has the potential for an excellent response to corticosteroids or rituximab. We discuss the clinical presentation, imaging, histology (with its difficult distinction from lymphoma), management and follow-up of a case, including relapse and re-treatment following an initial response to rituximab.

Anti-N-methyl-D-aspartate receptor encephalitis.

A case of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis with an atypical finding of transient increased intracranial pressure is reported. Anti-NMDAR encephalitis is an underrecognized, novel and treatable form of encephalitis being increasingly identified as an explanation of encephalitis in young adults. Management of these patients requires a multidisciplinary approach involving neurologists, internists, nursing and rehabilitation staff. It is important for internists to recognize this condition and consider it in the differential diagnosis of encephalopathy. Internists also need to be familiar with the clinical manifestations and the treatment of the disease as they have an important role in the care of these patients during their prolonged stay in the hospital. Increased intracranial pressure is an atypical and underrecognized finding that has been only noted in a previous review on this disorder. It may present a diagnostic or management challenge in patients with anti-NMDAR encephalitis.

New insights in the prevention, diagnosis, and treatment of cryptococcal meningitis.

Cryptococcal meningitis (CM) remains a major cause of morbidity and mortality among immunocompromised patients, especially in areas of high HIV prevalence, although it can also cause disease in the apparently immunocompetent. Improving the management of HIV-associated CM is important to ensure that patients can survive to benefit from increasing access to ART. In this review we focus on recent advances in prevention, diagnosis, and treatment of CM.

The effects of brain injury on heart rate variability and the innate immune response in critically ill patients.

Brain injury and its related increased intracranial pressure (ICP) may lead to increased vagus nerve activity and the subsequent suppression of innate immunity via the cholinergic anti-inflammatory pathway. This may explain the observed increased susceptibility to infection in these patients. In the present study, we investigated the association between brain injury, vagus nerve activity, and innate immunity. We determined heart rate variability (HRV) as a measure of vagus nerve activity, plasma cytokines, and cytokine production of ex vivo lipopolysaccharide-stimulated whole blood in the first 4 days of admission to the neurological intensive care unit (ICU) in 34 patients with various forms of brain damage. HRV, immune parameters, and the correlations between these measures were analyzed in the entire group of patients and in subgroups of patients with conditions associated with high (intracranial hemorrhage [ICH]) and normal ICP (subarachnoid hemorrhage [SAH] with an extraventricular drain alleviating ICP). Healthy volunteers were used for comparison. HRV total spectral power and ex vivo-stimulated cytokine production were severely depressed in patients compared with healthy volunteers (p<0.05). Furthermore, HRV analysis showed that normalized units of high-frequency power (HFnu, corresponding with vagus nerve activity) was higher, and the low-frequency:high-frequency ratio (LF:HF, corresponding with sympathovagal balance) was lower in patients compared to healthy volunteers (p<0.05). HFnu correlated inversely with ex vivo-stimulated tumor necrosis factor-α (TNF-α) production (r=-0.22, p=0.025). The most pronounced suppression of ex vivo-stimulated cytokine production was observed in the ICH group. Furthermore, in ICH patients, HFnu correlated strongly with lower plasma TNF-α levels (r=-0.73, p=0.002). Our data suggest that brain injury, and especially conditions associated with increased ICP, is associated with vagus nerve-mediated immune suppression.

Anticardiolipin antibodies are frequently present in patients with idiopathic intracranial hypertension.

BACKGROUND: Anticardiolipin antibodies (ACL-Ab) are associated with various neurologic syndromes, but idiopathic intracranial hypertension (IIH) has only rarely been reported in this context. OBJECTIVES: To delineate the frequency and clinical and radiological features of, as well as the cause-and-effect relationship between, ACL-Ab and IIH. METHODS: We analyzed the medical records of patients with IIH hospitalized between January 1989 and September 1995. All patients underwent magnetic resonance imaging or magnetic resonance venography or angiography. Excluded were patients with intracranial hypertension due to dural sinus thrombosis or traumatic, structural, neoplastic, or infectious disorders. Patients who were found on at least 2 separate occasions to have increased IgG titers of ACL-Ab were identified and compared with patients without ACL-Ab. RESULTS: Six (43%) of 14 patients with IIH had ACL-Ab. No differences in clinical, laboratory, or radiological variables could be found between patients with and without ACL-Ab. Only 3 of the 11 ACL-Ab-positive patients had previous systemic or neurologic abnormalities associated with ACL-Ab. CONCLUSIONS: Anticardiolipin antibodies may cause IIH through mechanisms unrelated to major venous thrombosis. Idiopathic intracranial hypertension is frequently associated with ACL-Ab and can be the presenting symptom of the antiphospholipid syndrome. There are no major clinical, laboratory, or radiological features that distinguish between patients with IIH with and without ACL-Ab.