Relationships between bronchiectasis and time to achieving target trough immunoglobulin G levels in patients with common variable immunodeficiency.

Background: The main treatment of common variable immunodeficiency (CVID) is to maintain immunoglobulin G (IgG) levels within the target range. However, trough IgG levels differ among patients with similar body mass index (BMI) and those receiving the same dose of immunoglobulin replacement therapy (IGRT). A crucial factor that underlies these differences is the presence of extensive bronchiectasis, which is associated with the immunoglobulin salvage pathway. Objective: We compared trough IgG levels in patients with CVID and with and in those without bronchiectasis who had received the same dose of IGRT for 2 years to determine the association of IgG level with infection frequency. Method: This retrospective cohort study included 61 patients with CVID, of whom 21 had bronchiectasis. We reviewed the electronic records for demographic variables, baseline immunoglobulin levels, mean trough IgG levels over 2 years, efficacy levels (trough IgG level - baseline IgG level), the time interval from treatment initiation to achieving the target trough IgG level (700 mg/dL), and the number of infections. Results: The median age of the patients was 39 years (IQR, 27-51), and 29 were women (47.5%). There were no significant differences between the groups in terms of age, age at diagnosis, delay in diagnosis, sex, BMI, IGRT type (subcutaneous or intravenous), and baseline immunoglobulin levels. Trough IgG and efficacy levels were lower (P < 0.001 and P = 0.016, respectively), the time required to achieve the target IgG level was longer in patients with bronchiectasis than in those without bronchiectasis, and this time interval was significantly associated with the infection frequency. Trough IgG and albumin levels were correlated (p = 0.007), with minor differences between the groups (p = 0.04). Conclusion: Bronchiectasis was significantly associated with a longer time to achieve the target IgG levels. These long-term differences between the patients with and those without bronchiectasis have significant clinical implications.

High digit ratio (2D:4D) is associated with attack frequency and severity in hereditary angioedema patients.

BACKGROUND: Hereditary angioedema (HAE) caused by a deficiency or dysfunction of the plasma protease C1-inhibitor is a rare autosomal-dominant disorder. We explored a possible correlation between the ratio of the second and fourth finger lengths (2D:4D) and the frequency of HEA attacks, and whether the ratio might predict laryngeal attack. METHOD: We evaluated 35 HEA patients aged 19 to 66 years; 3 were subsequently excluded. The 2D:4D ratio was calculated by dividing the length of the second finger by that of the fourth finger of both hands. A structured clinical questionnaire exploring HAE course and treatment over the prior year was administered. RESULTS: Of the 32 participants, 56.25 % (n = 18) were female. Of them, those with high 2D:4D ratios suffered significantly more laryngeal attacks than others; 93.3% of patients with high 2D:4D ratios experienced ≥5 attacks annually, significantly more than those with low ratios. Among type 2 HEA patients, 75 % of those experiencing ≥5 attacks annually had high 2D:4D ratios; all patients with low 2D:4D ratios reported <5 attacks annually. These significant effects were found for right-hand 2D:4D ratios and not left-hand 2D:4D ratios. CONCLUSION: The data suggest that intrauterine sex hormone exposure, which affects the 2D:4D ratio, is significantly associated with HEA attack frequency and severity, and laryngeal edema.

Relationship between Selective IgA Deficiency and COVID-19 Prognosis.

The prevalence and mortality rates of coronavirus disease 2019 (COVID-19) widely vary among populations. Mucosal immunity is the first barrier to the pathogen's entry into the body. Immunoglobulin A (IgA) is the primary antibody responsible for mucosal immunity. We explored the relationship between selective IgA deficiency (SIgAD) and COVID-19 severity. We included 424 patients (203 women) with COVID-19. Eleven patients had SIgAD. Laboratory data of patients with SIgAD and normal IgA levels were compared. The relationship between SIgAD and severe COVID-19 infection was explored using logistic regression analysis. In the univariate logistic regression analysis, the risk of severe COVID-19 disease in patients with SIgAD was approximately 7.7-fold higher than that in other patients (odds ratio [OR], 7.789; 95% confidence interval [CI], 1.665-36.690, P = 0.008), while it was 4-fold (OR, 4.053; 95% CI, 1.182-13.903, P = 0.026) higher in the multivariate logistic regression analysis. Serum IgA levels were positively correlated with total lymphocyte counts and negatively correlated with C-reactive protein levels, which was a risk factor for severe COVID-19. In patients with SIgAD, the number of severe acute respiratory coronaviruses 2 that pass through mucosal membranes may be increased, leading to complications such as cytokine storm syndrome and acute respiratory distress syndrome.

Memory B cells and serum immunoglobulins are associated with disease severity and mortality in patients with COVID-19.

PURPOSE OF THE STUDY: The aim of this study was to investigate the relationship of B cell-mediated immunity with disease severity and mortality in patients with COVID-19. STUDY DESIGN: In this retrospective cohort and single-centre study, 208 patients with laboratory-confirmed COVID-19 were recruited. A COVID-19 severity score, ranging from 0 to 10, was used to evaluate associations between various factors. Serum immunoglobulin levels and the number of cells in B lymphocyte subsets were measured and their association with disease severity and mortality in patients with COVID-19 examined. RESULTS: The median age of the patients was 50 (35-63) years and 88 (42%) were female. The number of deceased patients was 17. The median COVID-19 severity score was 8 (6-8) in deceased patients and 1 (0-2) in survivors. Deceased patients had significantly lower levels of total B lymphocytes, naive B cells, switched memory B cells, and serum IgA, IgG, IgG1 and IgG2 than recovered patients (all p<0.05). In addition, a significant negative correlation was found between the number of these parameters and COVID-19 severity scores. Decrease in the number of total B cells and switched memory B cells as well as lower serum IgA, IgG and IgG1 levels were independent risk factors for mortality in patients with COVID-19. CONCLUSION: In the present study, the prognosis of patients with COVID-19 was shown to be associated with the B cell subset and serum immunoglobulin levels.

Allergic diseases in the elderly population: a single-center experience.

BACKGROUND: Although allergic diseases are generally considered to be diseases of childhood and youth, the first symptoms of allergic diseases can be seen in old age sometimes. The aim of this study was to determine the prevalence and characteristics of allergic diseases in the elderly population admitted to the allergy unit on an outpatient basis. METHODS: The files of the patients who applied to our clinic's allergy unit during the 8-year period were retrospectively analyzed. The data of patients aged ≥ 65 years were obtained from the files of our allergy unit archive. RESULTS: A total of 1272 patients aged ≥ 65 years old were included in the study. The mean age was 70 years (range: 65-97 years). Most of the patients were female (n = 704, 55.3%). Of the patients, 887 (69.8%) presented with cutaneous symptoms, and urticaria was identified in 500 of them (56.3%). Drug hypersensitivity reactions were detected in 175 (13.7%) patients. A total of 71 (5.6%) patients had asthma, 65 (5.1%) had anaphylaxis, 48 (3.8%) had allergic rhinitis, 24 (1.9%) had hymenoptera venom allergy, and 18 (1.4%) had food allergies. Atopy history (OR = 2.323, 95% CI = 1.590-3.393, p < 0.001) and comorbidity (OR = 1.631, 95% CI = 1.050-2.533, p = 0.029) were found to be risk factors for drug hypersensitivity reactions. Male sex (OR = 3.462, 95% CI = 1.097-10.933, p = 0.034) and atopy history (OR = 14.877, 95% CI = 6.081-36.393, p < 0.001) were found to be risk factors for hymenoptera venom allergy. DISCUSSION: Diagnosis becomes difficult due to the perception that allergic diseases mainly affect young people. Clinical symptoms are not evident in the elderly and age-related difficulties are encountered in diagnostic tests. There is a need to develop specific guidelines for the diagnosis of allergic diseases in the elderly.