Cause Of Limbic Encephalitis Research Articles

A feline model of spontaneously occurring autoimmune limbic encephalitis

Autoimmune encephalitis (AE) is an important cause of encephalitis in humans and occurs at a similar rate to infectious encephalitis. It is frequently associated with antibodies against the extracellular domain of neuronal proteins. Among human AE, that with antibodies against leucine-rich glioma-inactivated 1 (LGI1) is one of the most prevalent forms, and was recently described in cats with limbic encephalitis (LE). In this study, we describe a large cohort (n = 32) of cats with AE, tested positive for voltage gated potassium channel (VGKC)-antibodies, of which 26 (81%) harboured LGI1-antibodies. We delineate their clinical and paraclinical features as well as long-term outcomes up to 5 years.Similar to human cases, most cats with LGI1-antibodies had a history of focal seizures (83%), clustering in the majority (88%), with interictal behavioural changes (73%). Among feline AE patients, there was no seizure type or other clinical characteristic that could distinguish LGI1-antibody positive from negative cats, unlike the pathognomic faciobrachial dystonic seizures seen in humans. Although six cats were euthanased in the first year for epilepsy-associated reasons, those attaining at least 1-year survival had good seizure control and quality of life with appropriate veterinary care and medication. Acute-phase immunotherapy (prednisolone) was given to the most severely unwell cases and its effect is retrospectively evaluated in 10 cats. Our data show LGI1-antibodies are an important cause of feline encephalitis, sharing many features with human AE. Further research should examine optimal therapeutic management strategies and the cause of LE in seronegative cats, building on paradigms established in the counterpart human disease.

Incidentally Detected Subclinical Limbic Encephalitis on 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography in a Patient with Myasthenia Gravis and Sarcoidosis: A Rare Immunological Triad?

Limbic encephalitis is the inflammation of the medial temporal lobe structures due to direct infectious or indirect autoimmune etiology. Sarcoidosis is a rare cause of limbic encephalitis, has been reported by some authors. Association has also been reported between sarcoidosis, myasthenia gravis, and limbic encephalitis. We report an interesting case of 18F-fluorodeoxyglucose positron emission tomography/computed tomography demonstrating limbic encephalitis and sarcoidosis in a known case of myasthenia gravis.

Limbic Encephalitis when the immune response is the hidden problem

Limbic Encephalitis (LE) defined as a rare and frequently underrecognized immunomediated syndrome, presents with a constellation of unspecific behavioral and neuropsychiatric symptoms, developing over weeks to months. Personality disturbance, complex partial mesotemporal seizures and a subacute severe impairment of short-term memory are the cardinal symptoms, reflecting the involvement of the grand lobe limbique. The etiology is still poorly understood. Until recently, paraneoplastic etiology was thought to be the most common cause of LE, often preceding the malignancy identification (60%–75%). In the last decade other associations have been considered, namely infectious or autoimmune diseases. It appears that non-paraneoplastic LE (unassociated with onconeural antibodies) is at least 5 times more frequent than the one where paraneoplastic antibodies are detected, even excluding the cases of paraneoplastic LE that are antibody-negative (40%). To date, co-occurrence of two possible etiologies of this rare syndrome, in the same patient, has never been reported.

A bout of confusion: Atypical presentations of Anti-Leucine-rich-Glioma-Inactivated 1(LGI-1) encephalitis – an emerging cause of limbic encephalitis (LE) (P5.393)

A bout of confusion: Atypical presentations of Anti-Leucine-rich-Glioma-Inactivated 1(LGI-1) encephalitis – an emerging cause of limbic encephalitis (LE) (P5.393)

GABAB Encephalitis: A Fifty-Two-Year-Old Man with Seizures, Dysautonomia, and Acute Heart Failure.

Autoantibodies to the γ-aminobutyric acid receptor, subtype B (GABAB), are a known cause of limbic encephalitis. The spectrum of clinical manifestations attributable to this antibody is not well defined at the present time. Here we present a case of GABAB encephalitis presenting with encephalopathy, status epilepticus, dysautonomia, and acute heart failure. To our knowledge, heart failure and dysautonomia have not yet been reported with this syndrome.

Electroencephalographic and fluorodeoxyglucose-positron emission tomography correlates in anti-N-methyl-d-aspartate receptor autoimmune encephalitis

ImportanceAnti-N-methyl-d-aspartate receptor (anti-NMDAR) autoimmune encephalitis is an increasingly recognized cause of limbic encephalitis (LE). Prolonged LE and limbic status epilepticus (LSE) share many features. The ability to distinguish between the two is crucial in directing appropriate therapy because of the potential iatrogenesis associated with immunosuppression and anesthetic-induced coma.ObservationsA 34-year-old woman with recurrent LE developed behavioral changes, global aphasia, and repetitive focal and generalized tonic–clonic seizures. Because asymmetric rhythmic delta patterns recurred on electroencephalography (EEG) despite treatment with nonsedating antiepileptic drugs followed by anesthetic-induced coma, an investigation to distinguish LSE from LE was undertaken. Implanted limbic/temporal lobe depth electrodes revealed no epileptiform activity. Brain single-photon emission computerized tomography (SPECT) showed no hyperperfusion, and brain fluorodeoxyglucose-positron emission tomography (FDG-PET) showed hypermetabolism in the left frontal, temporal, and parietal cortices. Anti-N-methyl-d-aspartate receptor autoimmune encephalitis was diagnosed based detection of anti-NMDAR antibody in the cerebrospinal fluid (CSF). With chronic immunosuppression, the resolution of brain FDG-PET abnormalities paralleled clinical improvement.Conclusions and relevanceThis case of anti-NMDAR autoimmune encephalitis illustrates the challenges of distinguishing prolonged LE from LSE. We discuss the parallels between these two conditions and propose a management paradigm to optimize evaluation and treatment.

Hyponatremia and Voltage Gated Potassium Channel Antibody Associated Limbic Encephalitis

Limbic encephalitis may occur as an infectious, paraneoplastic, or autoimmune phenomenon. One such cause of limbic encephalitis is voltage gated potassium channel antibodies (VKGC). Hyponatremia with new cognitive decline may be one of the presenting symptoms. The exact mechanism of hyponatremia is unknown though findings consistent with syndrome of inappropriate antidiuretic hormone (SIADH) are observed. We retrospectively reviewed all cases admitted to an academic medical center with a diagnosis of limbic encephalitis (848 adults between 2004 to 2010) and found six cases of VGKC antibody associated limbic encephalitis. Three of the six cases had SIADH that completely or partially resolved with a combination of water restriction and immunotherapy. The reversibility of hyponatremia and limbic encephalitis with immunomodulation suggests an antibody-mediated cause. We further review available literature for association of hyponatremia and VGKC limbic encephalitis and propose mechanisms of for the hyponatremia in autoimmune encephalitis

A Typical Neurological Presentations in the ICU: Limbic Encephalitis

Common neurological emergencies include overdose or withdrawal from illegal substance abuse, adverse effects of prescription medications, seizures, metabolic encephalopathy, infections and cerebrovascular accidents. Following a thorough clinical and radiologic assessment, a small group of patients escape definitive diagnosis and autoimmune encephalitides should be considered. Of these, limbic encephalitis (LE) is the most common and may result from paraneoplastic or nonparaneoplastic sources. Common to both is the production of antibodies targeting epitopes in the brain parenchyma thought to be responsible for the clinical manifestations. Paraneoplastic Anti-N-methyl D-aspartate receptor (NMDAR) encephalitis is a common cause of LE and has gained awareness in neurological and psychiatric literature. Paraneoplastic and nonparaneoplastic anti NMDAR encephalitis typically presents in young, previously healthy females with subacute onset of psychiatric symptoms, respiratory insufficiency, orofacial dyskinesias, autonomic instability and seizures. Paraneoplastic LE is induced by antibody production against NMDAR with occult ovarian teratoma being the most common inciting tumor. LE has also been described in association with other tumors and also without tumors. The latter are known as nonparaneoplastic or primary autoimmune disease. Diagnosis requires both clinical suspicion along with prompt serum and cerebrospinal fluid analysis for antibody detection. Immunotherapy to remove and suppress these antibodies along with resection of an identified tumor is the therapy of choice. This article will review the clinical presentation and management of LE in patients who present to the medical intensive care unit.

Safety of pre‐engraftment prophylactic foscarnet administration after allogeneic stem cell transplantation

Human herpesvirus-6 (HHV-6) is a major cause of limbic encephalitis with a dismal prognosis after allogeneic hematopoietic stem cell transplantation (SCT). Because our previous trial of preemptive therapy with foscarnet sodium (phosphonoformic acid; PFA) failed to prevent HHV-6 encephalitis, we conducted a prospective study to examine the safety of prophylactic PFA administration and elucidate the changes in the plasma HHV-6 DNA levels in the early post-SCT period. Plasma HHV-6 DNA was measured thrice weekly from day 6. PFA, 90 mg/kg/day, was administered from days 7 to 21 after bone marrow or peripheral blood SCT and to day 25 after umbilical cord blood transplantation. Of the 10 patients enrolled, 2 dropped out of the study, 1 because of early death, and 1 with a low glomerular filtration rate. Grade 3 or greater adverse events occurred in 9 of the 10 prophylactic PFA patients and in 7 of the 10 control patients who had clinical backgrounds similar to the study subjects and underwent SCT during the same period. Neurological disorders developed in none of the study subjects but in 4 of the 10 control patients, including 2 with HHV-6 encephalitis. HHV-6 reactivation occurred in 3 of the 10 study subjects. The prophylactic PFA regimen was thus safe and it may reduce the risk of limbic encephalitis, but is not considered to be potent enough to prevent HHV-6 reactivation.

Preemptive therapy of human herpesvirus-6 encephalitis with foscarnet sodium for high-risk patients after hematopoietic SCT

Human herpesvirus-6 (HHV-6) is a major cause of limbic encephalitis with a dismal prognosis after allogeneic hematopoietic SCT (HSCT). A prospective, multicenter study was conducted to assess the safety and efficacy of preemptive therapy with foscarnet sodium (PFA) for the prevention of HHV-6 encephalitis. Plasma HHV-6 DNA was measured thrice weekly from day 7 until day 36 after umbilical cord blood transplantation (UCBT) or HSCT from HLA-haploidentical relatives. PFA, 90 mg/kg/day, was started when HHV-6 DNA exceeded 5 × 10(2) copies/mL. Mild and transient adverse events were associated with PFA in 7 of 8 patients. Twelve of 15 UCBT recipients became positive for HHV-6 DNAemia, defined by greater than 1 × 10(2) copies/mL of HHV-6 DNA in plasma. The virus exceeded 5 × 10(2) copies/mL in seven patients, whereas none of the five HLA-haploidentical HSCT recipients became positive. One patient developed mild limbic encephalitis just after initial PFA administration. Preemptive PFA therapy is safe, but as HHV-6 DNAemia can abruptly develop before neutrophil engraftment in UCBT recipients, prophylactic PFA administration from day 7 or earlier after UCBT may be needed.

A report of human herpesvirus 6-associated encephalitis in a solid organ transplant recipient and a review of previously published cases

Human herpesvirus 6 (HHV-6) is a common pathogen among children, classically presenting as fever and rash that resolve without specific therapy (exanthem subitum or roseola infantum). Also identified as a pathogen in hematopoietic cell transplant and solid organ transplant (SOT) recipients, it has been recognized as a cause of limbic encephalitis, characterized by confusion and amnesia, with magnetic resonance imaging findings of T2 hyperintensity of the amygdala and hippocampus. We report a case of limbic encephalitis associated with HHV-6 infection in a liver transplant recipient, and we review previously reported cases of HHV-6 encephalitis in SOT recipients.