Reduction in mucosal-associated invariant T cells (MAIT) in APECED patients is associated with elevated serum IFN-γ concentration.

Mucosal-associated invariant T cells (MAIT) are innate-like lymphocytes enriched in mucosal organs where they contribute to antimicrobial defense. APECED is an inborn error of immunity characterized by immune dysregulation and chronic mucocutaneous candidiasis. Reduction in the frequency of circulating MAITs has been reported in many inborn errors of immunity, but only in a few of them, the functional competence of MAITs has been assessed. Here, we show in a cohort of 24 patients with APECED, that the proportion of circulating MAITs was reduced compared with healthy age and sex-matched controls (1.1% vs. 2.6% of CD3+ T cells; p < 0.001) and the MAIT cell immunophenotype was more activated. Functionally the IFN-γ secretion of patient MAITs after stimulation was comparable to healthy controls. We observed in the patients elevated serum IFN-γ (46.0 vs. 21.1 pg/mL; p = 0.01) and IL-18 (42.6 vs. 13.7 pg/mL; p < 0.001) concentrations. Lower MAIT proportion did not associate with the levels of neutralizing anti-IL-22 or anti-IL-12/23 antibodies but had a clear negative correlation with serum concentrations of IFN-γ, IL-18, and protein C-reactive protein. Our data suggest that reduction of circulating MAITs in patients with APECED correlates with chronic type 1 inflammation but the remaining MAITs are functionally competent.

Neurological Diseases and Prevalence of Antineuronal Antibodies in Patients with Autoimmune Polyendocrine Syndrome Type 1 - A National Cohort Study.

Autoimmune polyendocrine syndrome type 1 (APS-1) is a rare monogenic disease caused by mutations in the autoimmune regulator gene. Although the disease-associated autoantibodies mostly target endocrine organs, autoantibodies from patients with APS-1 bind also to rat brain structures. The patients often have GAD65-antibodies, that can cause autoimmune encephalitis. However, neurological manifestations of APS-1 have not been systematically explored. We conducted a retrospective chart review on 44 Finnish patients with APS-1 (median age 38 years, 61% females) and collected all their neurological diagnoses. To assess the prevalence of serum antineuronal antibodies in APS-1, serum samples of 24 patients (median age 36 years, 63% females) were analyzed using a fixed cell-based assay. Of the 44 APS-1 patients, 10 (23%) had also received a diagnosis of a neurological disease. Of these neurological comorbidities, migraine (n = 7; 16%), central nervous system infections (n = 3; 7%), and epilepsy (n = 2; 5%) were the most prevalent. Other diagnoses recorded for single patients were axonal sensorimotor polyneuropathy, essential tremor, idiopathic intracranial hypertension, ischemic stroke, and trigeminal neuralgia. Serum antineuronal antibodies were detected in 42% of patients tested (10/24, 50% females, median age 42 years), GAD65 antibodies being the most common finding. Antibodies against glycine and aquaporin 4 were found in low titers. In four patients, relatively high titers of GAD65 antibodies without coexisting type 1 diabetes were found, but none presented with GAD65-encephalitis. Our study suggests an association between APS-1 and neurological disorders, the mechanisms of which are to be further investigated.

A novel missense mutation in the AIRE gene underlying autoimmune polyglandular syndrome type 1.

The immune regulator gene AIRE plays an essential role in the establishment of immune tolerance and the prevention of autoimmunity. This transcription factor plays a critical role in promoting self-tolerance in the thymus by regulating the expression of a large number of self-antigens that share the common feature of being tissue-restricted in their expression pattern in the periphery. Dysfunction of AIRE in humans causes a rare disease, autoimmune polyglandular syndrome type 1 (APS1), characterized by an autoimmune response against peripheral tissues, particularly endocrine tissues. Although a few dominant mutations have been described, the inactivation of AIRE is usually caused by recessive mutations. Recent data suggests that alterations in AIRE function contribute not only to APS1 but also to more common forms of autoimmune disease. Here, we present a previously unreported missense mutation (NM_000383.2:c.260 T > C) in exon 2 of the AIRE gene, predicted to cause the substitution (p.(Leu87Pro)) in the CARD domain of the AIRE protein. When inherited in conjunction with another dysfunctional AIRE allele, this mutation was associated with immune dysregulation in a pediatric patient. The presence of hypergammaglobulinemia, malabsorption syndrome, ectodermal dysplasia, mucocutaneous candidiasis, vitiligo, and hypothyroidism as well as the presence of multiple autoantibodies allowed us to confirm an APS1 diagnosis.

Ruxolitinib Rescues Multiorgan Clinical Autoimmunity in Patients with APS-1.

Autoimmune polyendocrine syndrome type-1 (APS-1) is caused by mono- or biallelic loss-of-function variants of the autoimmune regulator gene AIRE underlying early-onset multiorgan autoimmunity and the production of neutralizing autoantibodies against cytokines, accounting for mucosal candidiasis and viral diseases. Medical intervention is essential to prevent or attenuate autoimmune manifestations. Ruxolitinib is a JAK inhibitor approved for use in several autoimmune conditions. It is also used off-label to treat autoimmune manifestations of a growing range of inborn errors of immunity. We treated three APS-1 patients with ruxolitinib and followed them for at least 30 months. Tolerance was excellent, with no medical or biological adverse events. All three patients had remarkably positive responses to ruxolitinib for alopecia, nail dystrophy, keratitis, mucosal candidiasis, steroid-dependent autoimmune hepatitis, exocrine pancreatic insufficiency, renal potassium wasting, hypoparathyroidism, and diabetes insipidus. JAK inhibitors were therefore considered an effective treatment in three patients with APS-1. Our observations suggest that JAK/STAT pathways are involved in the pathogenesis of APS-1 autoimmune manifestations. They also suggest that JAK inhibitors should be tested in a broader range of APS-1 patients.

Lessons from primary immunodeficiencies: Autoimmune regulator and autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy.

The discovery of the autoimmune regulator (AIRE) protein and the delineation of its critical contributions in the establishment of central immune tolerance has significantly expanded our understanding of the immunological mechanisms that protect from the development of autoimmune disease. The parallel identification and characterization of patient cohorts with the monogenic disorder autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), which is typically caused by biallelic AIRE mutations, has underscored the critical contribution of AIRE in fungal immune surveillance at mucosal surfaces and in prevention of multiorgan autoimmunity in humans. In this review, we synthesize the current clinical, genetic, molecular and immunological knowledge derived from basic studies in Aire-deficient animals and from APECED patient cohorts. We also outline major advances and research endeavors that show promise for informing improved diagnostic and therapeutic approaches for patients with APECED.

Screening patients with autoimmune endocrine disorders for cytokine autoantibodies reveals monogenic immune deficiencies.

BACKGROUND: Autoantibodies against type I interferons (IFN) alpha (α) and omega (ω), and interleukins (IL) 17 and 22 are a hallmark of autoimmune polyendocrine syndrome type 1 (APS-1), caused by mutations in the autoimmune regulator (AIRE) gene. Such antibodies are also seen in a number of monogenic immunodeficiencies. OBJECTIVES: To determine whether screening for cytokine autoantibodies (anti-IFN-ω and anti-IL22) can be used to identify patients with monogenic immune disorders. METHODS: A novel ELISA assay was employed to measure IL22 autoantibodies in 675 patients with autoimmune primary adrenal insufficiency (PAI) and a radio immune assay (RIA) was used to measure autoantibodies against IFN-ω in 1778 patients with a variety of endocrine diseases, mostly of autoimmune aetiology. Positive cases were sequenced for all coding exons of the AIRE gene. If no AIRE mutations were found, we applied next generation sequencing (NGS) to search for mutations in immune related genes. RESULTS: We identified 29 patients with autoantibodies against IFN-ω and/or IL22. Of these, four new APS-1 cases with disease-causing variants in AIRE were found. In addition, we identified two patients with pathogenic heterozygous variants in CTLA4 and NFKB2, respectively. Nine rare variants in other immune genes were identified in six patients, although further studies are needed to determine their disease-causing potential. CONCLUSION: Screening of cytokine autoantibodies can efficiently identify patients with previously unknown monogenic and possible oligogenic causes of autoimmune and immune deficiency diseases. This information is crucial for providing personalised treatment and follow-up of patients and their relatives.

Cytokine-specific autoantibodies shape the gut microbiome in autoimmune polyendocrine syndrome type 1.

BACKGROUND: Gastrointestinal dysfunction is a frequent and disabling manifestation of autoimmune polyendocrine syndrome type 1 (APS-1), a rare monogenic multiorgan autoimmune disease caused by the loss of central AIRE-controlled immune tolerance. OBJECTIVES: This study aimed to understand the role of the gut microbiome in APS-1 symptoms and potentially alleviate common gastrointestinal symptoms by probiotic intervention. METHODS: This study characterized the fecal microbiomes of 28 patients with APS-1 and searched for associations with gastrointestinal symptoms, circulating anti-cytokine autoantibodies, and tryptophan-related metabolites. Additionally, daily doses of the probiotic Lactobacillus rhamnosus GG were administered for 3 months. RESULTS: Of 581 metagenomic operational taxonomic units (mOTUs) characterized in total, 14 were significantly associated with patients with APS-1 compared with healthy controls, with 6 mOTUs depleted and 8 enriched in patients with APS-1. Four overabundant mOTUs were significantly associated with severity of constipation. Phylogenetically conserved microbial associations with autoantibodies against cytokines were observed. After the 3-month intervention with the probiotic L rhamnosus GG, a subset of gastrointestinal symptoms were alleviated. L rhamnosus GG abundance was increased postintervention and corresponded with decreased abundances of Alistipes onderdonkii and Collinsella aerofaciens, 2 species positively associated with severity of diarrhea in patients with APS-1. CONCLUSIONS: The APS-1 microbiome correlates with several APS-1 symptoms, some of which are alleviated after a 3-month L rhamnosus GG intervention. Autoantibodies against cytokines appear to shape the gut microbiome by positively correlating with a taxonomically consistent group of bacteria.

Autoimmune polyendocrine syndrome type 1: an Italian survey on 158 patients.

BACKGROUND: Autoimmune Polyglandular Syndrome type 1 (APS-1) is a rare recessive inherited disease, caused by AutoImmune Regulator (AIRE) gene mutations and characterized by three major manifestations: chronic mucocutaneous candidiasis (CMC), chronic hypoparathyroidism (CH) and Addison's disease (AD). METHODS: Autoimmune conditions and associated autoantibodies (Abs) were analyzed in 158 Italian patients (103 females and 55 males; F/M 1.9/1) at the onset and during a follow-up of 23.7 ± 15.1 years. AIRE mutations were determined. RESULTS: The prevalence of APS-1 was 2.6 cases/million (range 0.5-17 in different regions). At the onset 93% of patients presented with one or more components of the classical triad and 7% with other components. At the end of follow-up, 86.1% had CH, 77.2% AD, 74.7% CMC, 49.5% premature menopause, 29.7% autoimmune intestinal dysfunction, 27.8% autoimmune thyroid diseases, 25.9% autoimmune gastritis/pernicious anemia, 25.3% ectodermal dystrophy, 24% alopecia, 21.5% autoimmune hepatitis, 17% vitiligo, 13.3% cholelithiasis, 5.7% connective diseases, 4.4% asplenia, 2.5% celiac disease and 13.9% cancer. Overall, 991 diseases (6.3 diseases/patient) were found. Interferon-ω Abs (IFNωAbs) were positive in 91.1% of patients. Overall mortality was 14.6%. The AIRE mutation R139X was found in 21.3% of tested alleles, R257X in 11.8%, W78R in 11.4%, C322fsX372 in 8.8%, T16M in 6.2%, R203X in 4%, and A21V in 2.9%. Less frequent mutations were present in 12.9%, very rare in 9.6% while no mutations in 11% of the cases. CONCLUSIONS: In Italy, APS-1 is a rare disorder presenting with the three major manifestations and associated with different AIRE gene mutations. IFNωAbs are markers of APS-1 and other organ-specific autoantibodies are markers of clinical, subclinical or potential autoimmune conditions.

Neurotrophic keratitis in autoimmune polyglandular syndrome type 1: a case report.

BACKGROUND: Autoimmune polyglandular syndrome type 1 (APS-1) is a rare autosomal recessive disease. In patients with APS-1, the most frequently reported ocular manifestations are keratoconjunctivitis with dry eye and retinal degeneration. However, to our knowledge, no research studies have reported the relationship between APS-1 and neurotrophic keratitis (NK). Possible explanations such as limbus cell deficiency being the primary cause of APS-1 keratopathy are not applicable to our unusual case of the patient with APS-1 presenting as ocular surface disease with NK. Our case findings suggest a new explanation for the observed corneal pathology and a potential treatment for these patients. CASE PRESENTATION: A 27-year-old woman was referred to our hospital because of intermittent blurred vision and recalcitrant ocular surface problems in both eyes for many years. She has a history of autoimmune polyglandular syndrome type 1 (APS-1), which includes hypothyroidism, hypoparathyroidism, hypoadrenalism, and hypogonadotropic hypogonadism. In vivo confocal microscopy clearly demonstrated significant degeneration of the sub-basal nerve plexus and stromal nerve bundles in her corneas bilaterally. She was diagnosed with severe NK and ocular surface disease caused by dry eye. Treatment included the application of therapeutic soft contact lenses and punctual occlusion; however, both treatments had a limited effect. CONCLUSION: Patients with APS-1 may have ocular surface disease and severe damage to corneal nerves. Regular follow-up and treatment focusing on the regeneration of corneal nerves is particularly important in these patients.

Delay in the Diagnosis of APECED: A Case Report and Review of Literature from Iran.

Autoimmune polyendocrinopathy candidiasis ectodermal dystrophy (APECED) syndrome is a rare monogenic autosomal recessive disorder caused by biallelic mutations in the AIRE (autoimmune regulator) gene. Patients with APECED present with heterogeneous endocrine and non-endocrine manifestations. In this study, we report an Iranian patient who presented with Addison disease, chronic mucocutaneous candidiasis, alopecia totalis, keratopathy and asplenia treated as an isolated endocrinopathy for 25 years. In the adulthood, the diagnosis of APECED was made by genetic analysis which demonstrated homozygous nonsense p.R257* (c.769C>T) mutation of AIRE. APECED has been shown to be frequent in some ethnicities including Iranian Jews. Therefore, we reviewed 39 Iranian APECED patients published in the literature. We found that most of the Iranian patients were of Jewish ethnic background and presented hypoparathyroidism, adrenal insufficiency, and candidiasis as the main clinical manifestation.

Autoimmune Polyglandular Syndrome Type 1: a case report.

BACKGROUND: Mutations of the autoimmune regulator gene (AIRE), located on chromosome 21q22.3, are recognized as the cause of a rare monogenic organ-specific autoimmune disorder called autoimmune polyglandular syndrome type 1 (APS-1). Three major components of this syndrome include chronic mucocutaneous candidiasis (CMC), hypoparathyroidism, and adrenocortical failure. CASE PRESENTATION: We report a 19-year-old girl, who was born in an Iranian Muslim family with a clinical diagnosis of APS-1. To identify the causative mutation, a direct sequencing of the entire AIRE gene sequence was performed by Sanger sequencing method. Three distinct variants were discovered, including c.1095 + 2 T > A, c.1197 T > C (rs1800521) and c.1578 T > C (rs1133779), in intron 9, exons 10 and 14 of the AIRE gene, respectively. CONCLUSIONS: To the best of our knowledge, this is the first report of an Iranian Muslim APS-1 patient with combination of these variations. In addition, the effect of c.1095 + 2 T > A mutation on AIRE mRNA expression was reported for the first time. This study expands the diversity of variants that could cause APS-1. More genetic studies are required to determine the exact frequency of these variants and their diagnostic significance.

The heterogeneity of autoimmune polyendocrine syndrome type 1: Clinical features, new mutations and cytokine autoantibodies in a Brazilian cohort from tertiary care centers.

Autoimmune polyendocrine syndrome type 1 (APS1) is characterized by multiorgan autoimmunity. We aim at characterizing a multi-center Brazilian cohort of APS1 patients by clinical evaluation, searching mutation in the AIRE gene, measuring serum autoantibodies, and investigating correlations between findings. We recruited patients based on the clinical criteria and tested them for AIRE mutations, antibodies against interferon type I and interleukins 17A, 17F and 22. We identified 12 unrelated families (13 patients) with typical signs of APS1 in the proband, and the screening of relatives recognized an asymptomatic child. Candidiasis was present in all cases, and 19 other manifestations were observed. All patients carried one of 10 different mutations in AIRE, being 3 new ones, and were positive for anti-interferon type I serum antibody. Anti-interleukin-17A levels inversely correlated with the number of manifestations in each patient. This negative correlation may suggest a protective effect of anti-interleukin-17A with a potential therapeutic application.

Long-Term Parathyroid Hormone 1-34 Replacement Therapy in Children with Hypoparathyroidism.

OBJECTIVE: To determine whether multiple daily injections of parathyroid hormone (PTH) 1-34 are safe and effective as long-term therapy for children with hypoparathyroidism. STUDY DESIGN: Linear growth, bone accrual, renal function, and mineral homeostasis were studied in a long-term observational study of PTH 1-34 injection therapy in 14 children. METHODS: Subjects were 14 children with hypoparathyroidism attributable to autoimmune polyglandular syndrome type 1 (N = 5, ages 7-12 years) or calcium receptor mutation (N = 9, ages 7-16 years). Mean daily PTH 1-34 dose was 0.75 ± 0.15 µg/kg/day. Treatment duration was 6.9 ± 3.1 years (range 1.5-10 years). Patients were evaluated semiannually at the National Institutes of Health Clinical Center. RESULTS: Mean height velocity and lumbar spine, whole body, and femoral neck bone accretion velocities were normal throughout the study. In the first 2 years, distal one-third radius bone accrual velocity was reduced compared with normal children (P < .003). Serum alkaline phosphatase correlated with PTH 1-34 dose (P < .006) and remained normal (235.3 ± 104.8 [SD] U/L, N: 51-332 U/L). Mean serum and 24-hour urine calcium levels were 2.05 ± 0.11 mmol/L (N: 2.05-2.5 mmol/L) and 6.93 ± 1.3 mmol/24 hour (N: 1.25-7.5 mmol/24 hour), respectively-with fewer high urine calcium levels vs baseline during calcitriol and calcium treatment (P < .001). Nephrocalcinosis progressed in 5 of 12 subjects who had repeated renal imaging although renal function remained normal. CONCLUSIONS: Twice-daily or thrice-daily subcutaneous PTH 1-34 injections provided safe and effective replacement therapy for up to 10 years in children with hypoparathyroidism because of autoimmune polyglandular syndrome type 1 or calcium receptor mutation.

Assessment of autoantibodies to interferon-ω in patients with autoimmune polyendocrine syndrome type 1: using a new immunoprecipitation assay.

BACKGROUND: Measurements of autoantibodies to interferon-ω (IFN-ω) in patients with autoimmune polyglandular syndrome type 1 (APS-1) were performed using a new immunoprecipitation assay (IPA) based on 125I-labeled IFN-ω. METHODS: We have developed and validated a new IPA based on 125I-labeled IFN-ω. Sera from 78 patients (aged 3-78 years) with clinically diagnosed APS-1, 35 first degree relatives, 323 patients with other adrenal or non-adrenal autoimmune diseases and 84 healthy blood donors were used in the study. In addition, clinical features and autoimmune regulator (AIRE) genotype for the APS-1 patients were analyzed. RESULTS: Sixty-six (84.6%) of 78 APS-1 patients were positive for IFN-ω Ab using 125I-labeled IFN-ω IPA. IFN-ω Ab was the most prevalent of the six different autoantibodies tested in this group of APS-1 patients. All 66 IFN-ω Ab-positive APS-1 patients had AIRE mutations and 7 IFN-ω Ab-negative patients had no detectable AIRE mutations, whereas 3 (3.8%) patients were discrepant for IFN-ω Ab positivity and AIRE mutation results. Out of autoimmune controls studied, two patients were positive for IFN-ω Ab. Positivity and levels of IFN-ω Ab in the APS-1 patients studied were similar irrespective of patient's clinical phenotype and AIRE genotype. Furthermore, IFN-ω Ab levels did not change over time (up to 36 years of disease duration) in 8 APS-1 patients studied. CONCLUSIONS: We have developed a novel, highly sensitive and specific assay for measurement of IFN-ω Ab. It provides a simple and convenient method for the assessment of patients with APS-1 and selecting patients suspected of having APS-1 for AIRE gene analysis.

The biophysical and biochemical properties of the autoimmune regulator (AIRE) protein.

AIRE (for autoimmune regulator) is a multidomain protein that performs a fundamental function in the thymus and possibly in the secondary lymphoid organs: the regulation, especially in the sense of activation, of the process of gene transcription in cell lines deputed to the presentation of self-antigens to the maturing T lymphocytes. The apoptosis of the elements bearing T-cell receptors with critical affinity for the exhibited self-antigens prevents the escape of autoreactive clones and represents a simple and efficient mechanism of deletional self-tolerance. However, AIRE action relies on an articulated complex of biophysical and biochemical properties, in most cases attributable to single subspecialized domains. Here a thorough review of the matter is presented, with a privileged look at the pathogenic changes of AIRE that interfere with such properties and lead to the impairment in its chief function.

Analysis of the autoimmune regulator gene in patients with autoimmune non-APECED polyendocrinopathies.

The pathogenesis of autoimmunity was derived from a complex interaction of genetic and environmental factors. Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy is a rare autosomal recessive disease caused by mutations in the autoimmune regulator (AIRE) gene. AIRE gene variants and, in particular, heterozygous loss-of-function mutations were also discovered in organ-specific autoimmune disorders, possibly contributing to their etiopathogenesis. It was suggested that even predisposition to develop certain autoimmune conditions may be derived from AIRE gene polymorphisms including S278R and intronic IVS9+6 G>A. In this study we unravel the hypothesis on whether AIRE gene variants may predispose individuals to associated autoimmune conditions in 41 Italian patients affected by non-APECED autoimmune polyendocrinopathies. We could not detect any heterozygous mutations of the AIRE gene. Although a trend of association was observed, heterozygous polymorphisms S278R and IVS9+6 G>A were detected in patients without statistically significant prevalence than in controls. Their putative contribution to autoimmune polyendocrinopathies and their predictive value in clinical strategies of disease development could be unravelled by analysing a larger sample of diseased patients and healthy individuals.

Early recognition of the APECED rash can accelerate the diagnosis of APECED.

Autoimmune-Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED) is a monogenic autoimmune disease most often resulting from biallelic loss-of-function variants in the autoimmune regulator (AIRE) gene. Although typically characterized by the classic triad of chronic mucocutaneous candidiasis, hypoparathyroidism, and adrenal insufficiency, we have recently reported that the clinical spectrum of the syndrome is far broader that previously described and that incorporation of an adjunct triad of APECED rash, autoimmune enteritis-associated intestinal dysfunction, and enamel hypoplasia in the classic triad manifestations could lead to earlier diagnosis. Among the adjunct triad manifestations, APECED rash occurs in 66% of American APECED patients by age 3, most often developing in the first year of life. Here, we describe the clinical and histological features of protracted APECED rash manifesting together with recurrent mucocutaneous candidiasis as the first two disease components of APECED in a 10-month-old girl.

Long-term remission of candidiasis with fermented lingonberry mouth rinse in an adult patient with APECED.

We report a long-term remission in candidiasis in a 57-year-old Finnish female with autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED) suffering from recurrent oral, esophageal, gastric, vaginal, and anal candidiasis since childhood. Candidiasis treatment with antifungal medicines fluconazole, itraconazole, posaconazole, voriconazole, caspofungin, nystatin, or amphotericin-B during 2008-2021 had variable effects and intermittent development of antifungal resistance and hospital periods. The patient started using fermented lingonberry juice (FLJ) as a mouth rinse daily in April 2021. No symptoms or mucosal signs of candidiasis in any part of the digestive system or vaginal area have been noticed during this exceptionally long-term 2 ½ year remission in candidiasis without antifungal medications.

Cutaneous Manifestations in Autoimmune Polyendocrinopathy-Candidiasis-Ectodermal Dystrophy (APECED): A Comprehensive Review.

Autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), or polyglandular autoimmune syndrome type 1 (PAS-1/APS-1), is a rare autosomal recessive disorder linked to mutations in the autoimmune regulator (AIRE) gene. This review provides a detailed analysis of cutaneous manifestations in APECED, focusing on chronic mucocutaneous candidiasis (CMC), alopecia areata (AA), and vitiligo. The classic triad of hypoparathyroidism, adrenal insufficiency, and CMC serves as a diagnostic cornerstone. However, the varied clinical spectrum of APECED, particularly its cutaneous presentations, poses a diagnostic challenge. CMC, often an early sign, varies in prevalence across populations, including Finnish (100%), Irish (100%), Saudi Arabian (80%), Italian (60-74.7%), North American (51-86%), and Croatian (57.1%) populations. Similarly, AA prevalence varies in different populations. Vitiligo also exhibits variable prevalence across regions. The review synthesizes the current knowledge arising from a narrative analysis of 14 significant human studies published in English up to October 2023. Moreover, this paper underscores the importance of early detection and monitoring, emphasizing cutaneous manifestations as key diagnostic indicators. Ongoing research and clinical vigilance are crucial for unraveling the complexities of this rare autoimmune syndrome and enhancing patient care.

Early-onset Chronic Keratitis as the First Presenting Component of Autoimmune Polyendocrinopathy Syndrome Type 1 (APS-1): A Case Report and Review of the Literature.

Autoimmune polyendocrine syndrome type 1 (APS-1), also referred to as autoimmune polyendocrinopathy-candidiasis-ectodermal dystrophy (APECED), is a rare monogenic autosomal recessive autoimmune disease. It is caused by mutations in the autoimmune regulator (AIRE) gene. APS-1 is diagnosed clinically by the presence of two of the three major components: chronic mucocutaneous candidiasis (CMC), hypoparathyroidism, and primary adrenocortical insufficiency. A 3.3-year-old girl was presented with a carpopedal spasm to the pediatric emergency clinic. She had a history of recurrent keratitis, and chronic candidiasis as urinary tract infections and oral thrashes. Hypoparathyroidism (HPT) was diagnosed based on low serum concentrations of calcium and parathyroid hormone and elevated serum concentrations of phosphate, and treatment with calcium and calcitriol supplementation was started. Genetic testing revealed homozygosity for nonsense c.769C>T (p.R257X) mutation in exon 6 in the AIRE gene which was reported previously. At the age of 5.6 years, she was presented with an adrenal crisis, and treatment with hydrocortisone and fludrocortisone was started. The reported case highlights that unexplained chronic keratitis in children may be the first and most severe component of this syndrome. The classic triad of APS-1 may also appear in the first decade of life.