A case of polyglandular autoimmune syndrome type I with unusual presentation

Case Report: Rituximab Improved Epileptic Spasms and EEG Abnormalities in an Infant With West Syndrome and Anti-NMDAR Encephalitis Associated With APECED

Background: Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy is a rare autosomal recessive disorder caused by a mutation in the autoimmune regulator gene. Patients with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy typically exhibit hypoparathyroidism, adrenocortical failure, and chronic mucocutaneous candidiasis. There are only a few case reports of autoimmune encephalitis during autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy, but not as an initial manifestation. Furthermore, there are no reports of patients with infantile spasms/West syndrome with autoimmune encephalitis, partly because the median age for paediatric patients with anti-N-methyl-D-aspartate receptor encephalitis, which is the most frequent and best characterised in paediatric autoimmune encephalitides, is 13–14 years. Herein, we present a case of a 3-month-old infant with autoimmune encephalitis as an initial manifestation of autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy who later developed infantile spasms/West syndrome.

Case Presentation: A 3-month-old girl was admitted to our hospital with a fever, involuntary movements in all four limbs, and right-side facial palsy. Acute central nervous system demyelination diseases were suspected from neuroimaging findings and the presence of the cerebrospinal fluid oligoclonal band. She did not respond to multiple methylprednisolone pulse therapies and later developed infantile spasms/West syndrome and diabetes mellitus. Rituximab, a chimeric mouse/human monoclonal antibody directed against human CD20 which depletes B cells, was initially administered as a treatment for autoimmune encephalitis. Unexpectedly, this treatment resulted in complete spasm cessation and resolution of hypsarrhythmia. The patient eventually showed severely delayed developmental milestones, and her electroencephalography findings showed periodic generalised slow spike-and-wave pattern.

Conclusions: Despite the limited ability to extrapolate findings from a single case, rituximab's effects may suggest that B cells play a crucial role in infantile spasms/West syndrome mechanisms; use of rituximab as an aetiology-specific treatment for infantile spasms/West syndrome patients with autoimmune encephalitis or its effectiveness for infantile spasms/West syndrome patients with other underlying mechanisms warrants further investigation.

A Novel Homozygous Mutation of the AIRE Gene in an APECED Patient From Pakistan: Case Report and Review of the Literature

Autoimmune-poly-endocrinopathy-candidiasis-ectodermal-dystrophy syndrome (APECED) is a rare monogenic recessive disorder caused by mutations in the autoimmune regulator (AIRE) gene. Criteria for the diagnosis of APECED are the presence of two of the following disorders: chronic mucocutaneous candidiasis (CMC), chronic hypoparathyroidism (CHP), and Addison's disease. APECED develops at high incidence in Finns, Sardinians, and Iranian Jews and presents with a wide range of clinical phenotypes and genotypes. In this manuscript, we report the clinical, endocrinological, and molecular features of a 16-year-old female patient from Pakistan living in Italy and presenting the major APECED clinical manifestations CMC, CHP, and primary adrenal insufficiency. Premature ovarian failure, chronic bronchopneumopathy, vitiligo, Hashimoto's thyroiditis emerged as associated diseases. In our patient, AIRE gene screening revealed the novel c.396G>C (p.Arg132Ser; p.R132S) mutation in homozygosity thus confirming APECED diagnosis. This is the first reported mutation within the nuclear localization signal (NLS) that is associated with APECED. The NLS mutation affects the nuclear import of classical transcription factors through nuclear pore by recognition of nuclear import receptors, the importin α molecules. By displaying crystal structures of the peptide containing the KRK basic residue cluster bound to α importins, we show that p.R132S replacement in 131-KRK-133 does not reproduce these interactions. Thus, we propose that the novel mutation exerts its pathogenetic effect by impairing the nuclear import of the Aire protein. The present case report is added to a limited series of Pakistani APECED patients who we reviewed from the scientific literature, mostly diagnosed on clinical findings.

GAD antibody-associated limbic encephalitis in a young woman with APECED

The autoimmune polyendocrinopathy–candidiasis–ectodermal dystrophy (APECED) syndrome is a genetic disorder caused by a mutation in the autoimmune regulator (AIRE) gene. Immune deficiency, hypoparathyroidism and Addison’s disease due to autoimmune dysfunction are the major clinical signs of APECED. We report on a 21-year-old female APECED patient with two inactivating mutations in the AIRE gene. She presented with sudden onset of periodic nausea. Adrenal insufficiency was diagnosed by means of the ACTH stimulation test. Despite initiation of hormone replacement therapy with hydrocortisone and fludrocortisone, nausea persisted and the patient developed cognitive deficits and a loss of interest which led to the diagnosis of depression. She was admitted to the psychiatric department for further diagnostic assessment. An EEG showed a focal epileptic pattern. Glutamic acid decarboxylase (GAD) antibodies, which had been negative eight years earlier, were now elevated in serum and in the cerebrospinal fluid. Oligoclonal bands were positive indicating an inflammatory process with intrathecal antibody production in the central nervous system (CNS). The periodic nausea was identified as dialeptic seizures, which clinically presented as gastrointestinal aura followed by episodes of reduced consciousness that occurred about 3–4 times per day. GAD antibody-associated limbic encephalitis (LE) was diagnosed. Besides antiepileptic therapy, an immunosuppressive treatment with corticosteroids was initiated followed by azathioprine. The presence of nausea and vomiting in endocrine patients with autoimmune disorders is indicative of adrenal insufficiency. However, our case report shows that episodic nausea may be a symptom of epileptic seizures due to GAD antibodies-associated LE in patients with APECED.