Diagnosing and Monitoring Celiac Patients with Selective IgA Deficiency: Still an Open Issue.

Although, the association between celiac disease (CD) and selective immunoglobulin A deficiency (SIgAD) has been known for more than fifty years, the procedures for diagnosing and monitoring patients with both conditions are still far from definitive. When serological markers were introduced as pre-bioptic investigations, it was immediately clear that searching for specific IgA antibodies without checking total serum IgA could lead to a failure in diagnosing IgA-deficient CD patients, while specific IgG antibodies could be useful as additional tests, because they are frequently found in the serum of affected patients. Nonetheless, until recently the diagnosis of CD in IgA-deficient patients was based on the few, fragmentary and often contradictory data available in literature. The introduction of the European Society for Pediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) guidelines in 2012 provided the current criteria for diagnosing CD in IgA-deficient patients, although some issues remained open, such as the selection of patients who should undergo specific IgG antibody testing and the choice of the most reliable IgG-based test for both diagnosis and follow-up. A real-life study recently assessed the impact of the 2012 ESPGHAN guidelines in diagnosing and monitoring CD in SIgAD patients, highlighting several pitfalls that can lead to operational uncertainties and difficulties in patient management. In the present report, the evolution of diagnostic tools and criteria for CD in SIgAD patients has been critically assessed, both strengths and open issues have been highlighted, and future perspectives for improving the current diagnostic protocols have been suggested.

Apolipoprotein E genotypes and plasma levels in mild cognitive impairment conversion to Alzheimer's disease: A follow-up study.

Mild cognitive impairment (MCI) is the transition stage between the normal aging process and dementia itself. The most common clinical phenotype is amnestic MCI (aMCI) [subtypes: single domain (sMCI) and multiple domains (mMCI)], which is considered prodromal to Alzheimer's disease (AD). The APOE (apolipoprotein E) e4 allele is the most important genetic risk factor for AD, but its association with MCI onset and conversion to AD is controversial. In this follow-up study of 88 aMCI patients (68% sMCI and 32% mMCI at baseline), we examined APOE genotypes and plasma levels in relation to MCI development and progression based on their clinical/cognitive data obtained at baseline and follow-up assessment (mean follow-up time = 6.6 ± 3.4 years). A control sample (n = 164) was collected in previous investigations. The overall conversion rate to mMCI or AD was 52.2%. The APOE e4 allele was associated with a higher risk of developing MCI (OR: 2.23; 95%CI: 1.22-4.08). The conversion rate in the e4 allele carriers (32% of the sample) was 71%, and the e4 allele was associated with a higher risk of conversion to mMCI/AD (OR: 4.1; 95%CI: 1.2-13.6). APOE e2 allele carriers were 7% (all sMCI) and none progressed to mMCI/AD. Among MCI subjects, e4 carriers had the lowest plasma apoE levels (37.8 ± 12.5 mg/L), and e2 carriers had the highest (78.6 ± 38.1 mg/L). APOE e4 is a risk allele for the development and progression of aMCI, the APOE e2 allele seems to be protective, and apoE levels associated to them are an integral part of their action. © 2016 Wiley Periodicals, Inc.