- Anti-NMDA receptor encephalitis is a recently recognized antibody-mediated inflammatory brain disease in children.
- Patients have neuropsychiatric symptoms, including changes in mental status, bizarre behavior, and seizures which are common among many infectious and metabolic diseases, and this makes the diagnosis much harder[1].
- Patients initially appear to have a mental illness, but they soon exhibit recurrent seizures and movement disorders[1].
- Testing for the anti-N-methyl-D-asparatate (NMDA) receptor antibodies can help diagnose this disease, and lead to reversal of symptoms with appropriate treatment.
- Treatment includes immunosuppressive therapy, anti-psychotic medication, and oncologic or infectious treatment to target the cause (if necessary)[2].
References
- Tumbi A, Gilani A, Scarff JR, Kaur G, Lippmann S. Anti-N-methyl-D Encephalitis. Innov Clin Neurosci, 2011. 8(9): p. 24-5.
- Peery HE, Day GS, Dunn S, Fritzler MJ, Pruss H, De Souza C, Doja A, Mossman K, Resch L, Xia C, Sakic B, Belbeck L, Foster WG. Anti-NMDA receptor encephalitis. The disorder, the diagnosis and the immunobiology. Autoimmun Rev, 2012. 11(12): p. 863-72.
- Dalmau J, Lancaster E, Martinez-Hernandez E, Rosenfeld MR, Balice-Gordon R. Clinical experience and laboratory investigations in patients with anti-NMDAR encephalitis. Lancet Neurol, 2011. 10(1): p. 63-74.
- Limbic encephalitis is a condition marked by the inflammation of the limbic system and other parts of the brain.
- It is caused by specific antibodies that attack the brain tissue, particularly the limbic areas.
- These antibodies are associated with the potassium channel, a protein crucial for proper neurological function. This causes a reduction in the number of potassium channels, decreasing the control over electrical activity of the brain[3].
- The typical symptoms are cognitive decline, behavioral abnormalities, memory loss and seizures[1].
- The diagnosis is confirmed by cerebrospinal fluid (CSF) inflammatory findings, Electroencephalography (EEG) or Magnetic Resonance Imaging (MRI) abnormalities in the temporal lobes, and antineuronal antibodies[2].
- There are two forms of autoimmune limbic encephalitis:
- Non-Paraneoplastic Limbic Encephalitis (NPLE)
- Caused by specific antibodies that attack different antigens in the brain, particularly the limbic areas.
- Occurs in patients without carcinomas.
- Responds well to treatment and health improves with immunosuppressive therapy[1].
- Paraneoplastic Limbic Encephalitis (PLE)
- Occurs rarely in patients with cancer, most commonly in small cell lung cancer and seminomas[3].
- Antibodies are made by the patients in their attempt to fight the cancer, but the antibodies inadvertently attack the brain tissue[3].
- Treatment is made based on the underlying oncologic condition and prognosis is poor.
- Non-Paraneoplastic Limbic Encephalitis (NPLE)
References
- Derry CP, Wilkie MD, Al-Shahi Salman R, Davenport RJ. Autoimmune limbic encephalitis. Clinical Medicine, 2011. 11(5): p. 476-8.
- Tüzün E, Dalmau J. Limbic encephalitis and variants: classification, diagnosis and treatment. Neurologist, 2007. 13(5): p. 261-71.
- Hashimoto’s encephalitis (HE) is a neuroendocrine autoimmune disease.
- HE involves inflammation of the brain, and is characterized by a high presence of thyroid antibodies similar to those present in Hashimoto’s thyroiditis.
- Patients may be euthyroid or hypothyroid upon onset[1].
- The etiology is unknown. The thyroid antibodies are thought to be a marker of the disease, rather than the cause of the problem[2].
- Symptoms are similar to other encephalopathic conditions; Clinical manifestations of HE may include seizures, behavioral and psychiatric manifestations, movement disorders, and coma[1,2].
- Treatment is very effective. The symptoms respond very well to immunosuppressive treatment[1,2].
- Thyroid replacement drugs may be needed depending on the condition of the thyroid.
References:
- Holanda NC, de Lima DD, Cavalcanti TB, Lucena CS, Bandeira F. Hashimoto's Encephalopathy: Systematic Review of the Literature and an Additional Case. J Neuropsychiatry Clin Neurosci, 2011. 23: p. 384-390.
- Sarosh, Irani. “Hashimoto’s Encephalitis.” The Encephalitis Society. Web. 17 February 2021.
Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal infections (PANDAS)
- PANDAS is a term is used to describe children and adolescents who have Obsessive Compulsive Disorder (OCD) and/or tic disorders, and in whom symptoms worsen following infections.
- Unlike typical OCD, where symptoms begin gradually, the children in the PANDAS subgroup have a very sudden, dramatic onset of the disorder.
- OCD, tics, and other symptoms usually occur in the aftermath of a strong stimulant to the immune system, such as a viral or bacterial infection.
- PANDAS is a clinical diagnosis, marked by the sudden onset of extreme symptoms, with the presence of a Streptococcal infections.
- Treatment includes
- Symptomatic treatment directed at the obsessive-compulsive symptoms.
- Antibiotic treatment to treat the Strep infection (if still present) and potentially in a prophylactic role.
- Immunosuppressive therapies to reduce inflammation.
References
- Pavone P, Parano E, Rizzo R, Trifiletti R. Autoimmune neuropsychiatric disorders associated with streptococcal infection: Sydenham chorea, PANDAS, and PANDAS variants. Child Neurol, 2006. 21(9): p. 727-36.