Expanding TREC and KREC Utility in Primary Immunodeficiency Diseases Diagnosis.

Primary immunodeficiency diseases (PID) area heterogeneous group of disorders caused by genetic defects of the immune system, which manifest clinically as recurrent infections, autoimmune diseases or malignancies. Early detection of PID remains a challenge, particularly in older children with milder and less specific symptoms. This study aimed to assess TREC and KREC diagnostic ability in PID. Data from children assessed by clinical immunologists at Speransky Children's Hospital, Moscow, Russia with suspected immunodeficiencies were analyzed between May 2013 and August 2016. Peripheral blood samples were sent for TREC/KREC, flow cytometry (CD3, CD4, CD8 and CD19), IgA and IgG analysis. A total of 434 children [189 healthy, 97 with group I and II PID (combined T and B cell immunodeficiencies & well-defined syndromes with immunodeficiency) and 148 group III PID (predominantly antibody deficiencies)] were included. Area under the curve (AUC) for TREC in PID groups I and II diagnosis reached 0.82 (CI = 0.75-0.90), with best model providing sensitivity of 65% and specificity of 92%. Neither TREC, nor KREC had added value in PID group III diagnosis. In this study, the predictive value of TREC and KREC in PID diagnosis was examined. We found that the TREC had some diagnostic utility for groups I and II PID. Possibly, addition of TREC measurements to existing clinical diagnostic algorithms may improve their predictive value. Further investigations on a larger cohort are needed to evaluate TREC/KREC abilities to be used as diagnostic tools on a wider scale.

Health-Related Quality of Life in Children and Adults with Primary Immunodeficiencies: A Systematic Review and Meta-Analysis.

BACKGROUND: Primary immunodeficiency diseases (PIDs) are a group of diseases that have been found to have an adverse impact on quality of life and health-related quality of life (HRQOL). OBJECTIVE: To systematically assess available evidence on the HRQOL of patients with PID. METHODS: We performed a literature search of all studies reporting HRQOL assessments in patients with PID published in English from inception to April 11, 2017, using MEDLINE and EMBASE. RESULTS: Of 1699 articles, 37 met the inclusion criteria. HRQOL was assessed by using various generic instruments. Child Health Questionnaire - Parent Form 50 and short-form 36 were the most frequently used (for children and adults, respectively). No PID-specific HRQOL instruments were used for children. HRQOL is significantly lower in adults with PID (mean score difference, -24.46; 95% CI, -34.57 to -14.34) and children (-10.06; 95% CI, -12.95 to -7.17) compared with the reference population and lower than in patients with other chronic conditions. There is a general agreement between child- and parent-reported data, although parents report child school-related HRQOL as more impaired than do children (6.19; 95% CI, 0.38 to 11.99). Most studies were of low to moderate quality and had methodological limitations. CONCLUSIONS: Available evidence suggests that patients with PID have a lower HRQOL than do healthy individuals and patients with other chronic conditions, including diabetes mellitus and juvenile idiopathic arthritis. No disease-specific instruments are available for children, and few options are available for adults. This finding highlights the need for developing PID-specific instruments that would allow for a more sensitive evaluation of PID impact on patient health and psychological well-being, school/work, and social activities.

TREC and KREC Levels as a Predictors of Lymphocyte Subpopulations Measured by Flow Cytometry.

Primary immunodeficiency diseases (PID) is a heterogeneous group of disorders caused by genetic defects of the immune system, which manifests clinically as recurrent infections, autoimmune diseases, or malignancies. Early detection of other PID remains a challenge, particularly in older children due to milder and less specific symptoms, a low level of clinician PID awareness and poor provision of hospital laboratories with appropriate devices. T-cell recombination excision circles (TREC) and kappa-deleting element recombination circle (KREC) in a dried blood spot and in peripheral blood using real-time polymerase chain reaction (PCR) are used as a tool for severe combined immune deficiency but not in PID. They represent an attractive and cheap target for a more extensive use in clinical practice. This study aimed to assess TREC/KREC correspondence with lymphocyte subpopulations, measured by flow cytometry and evaluate correlations between TREC/KREC, lymphocyte subpopulations and immunoglobulins. We carried out analysis of data from children assessed by clinical immunologists at Speransky Children's Hospital, Moscow, Russia with suspected immunodeficiencies between May 2013 and August 2016. Peripheral blood samples were sent for TREC/KREC, flow cytometry (CD3, CD4, CD8, and CD19), IgA, IgM, and IgG analysis. A total of 839 samples were analyzed for using TREC assay and flow cytometry and 931 KREC/flow cytometry. TREC demonstrated an AUC of 0.73 (95% CI 0.70-0.76) for CD3, 0.74 (95% CI 0.71-0.77) for CD4 and 0.67 (95% CI 0.63-0.70) for CD8, respectively, while KREC demonstrated an AUC of 0.72 (95% CI 0.69-0.76) for CD19. Moderate correlation was found between the levels of TREC and CD4 (r = 0.55, p < 0.01) and KREC with CD19 (r = 0.56, p < 0.01). In this study, promising prediction models were tested. We found that TREC and KREC are able to moderately detect abnormal levels of individual lymphocyte subpopulations. Future research should assess associations between TREC/KREC and other lymphocyte subpopulations and approach TREC/KREC use in PID diagnosis.

A national survey of Russian physicians' knowledge of diagnosis and management of food-induced anaphylaxis.

OBJECTIVES: Food allergy is an increasing burden worldwide and is a common problem within paediatric populations, affecting 5%-8% of children. Anaphylaxis caused by food proteins is a potentially life-threatening condition and all healthcare practitioners should be aware of its recognition and management. Russia is the largest country in Europe but it is still unknown whether physicians are prepared to diagnose and manage food-induced anaphylaxis effectively. We aimed to examine physicians' knowledge of diagnosis and management of food-induced anaphylaxis. SETTING, POPULATION AND OUTCOMES: A survey was designed and published online at VrachiRF.ru website (for registered Russian-speaking practicing physicians). We obtained information on respondents' clinical settings, experience and specialty. Survey questions were based on a characteristic clinical scenario of anaphylaxis due to food ingestion. Outcome measures consisted of correct answers to the anaphylaxis diagnosis and management questions. RESULTS: From a total of 707 of physicians accessed in the survey, 315 (45%) responded to the clinical scenario. 16 respondents reported training in allergy-immunology and have been excluded from the analysis, leaving the final sample size of 299. Respondents were paediatricians (68%) and other specialties adult physicians (32%). Overall, 100 (33%) of respondents diagnosed anaphylaxis, but only 29% of those making the correct diagnosis administered adrenalin (1:1000) intramuscular. Respondents working in secondary/tertiary clinics diagnosed anaphylaxis significantly more often (p=0.04) when compared with primary care/private practice physicians. This difference was also apparent as the most important influence on responses in the multivariate analysis. CONCLUSIONS: In this national sample of Russian physicians, we found poor knowledge in both anaphylaxis diagnosis and management. Our data show that the chance of being properly diagnosed with anaphylaxis is 33% and being appropriately treated with adrenalin is 10%. These findings highlight lack of anaphylaxis knowledge among Russian physicians, both paediatricians and other specialists and illustrates the urgent need for allergy/anaphylaxis training.