Immunological differences between insect venom-allergic patients with and without immunotherapy and asymptomatically sensitized subjects

BACKGROUND

Currently available tests are unable to distinguish between asymptomatic sensitization and clinically relevant Hymenoptera venom allergy. A reliable serological marker to monitor venom immunotherapy (VIT) does also not exist. Our aim was to find reliable serological markers to predict tolerance to bee and vespid stings.

METHODS

We included 77 asymptomatically sensitized subjects, 85 allergic patients with acute systemic sting reactions, and 61 allergic patients currently treated with VIT. Levels of sIgE and sIgG₄ to bee and vespid venom, rApi m 1, and rVes v 5 were measured immediately after allergic sting reactions or before sting challenges and 4 weeks later. All sting challenges were tolerated. The inhibitory activity was determined using BAT inhibition and ELIFAB assay.

RESULTS

Median sIgG₄ levels were 96-fold higher in VIT patients (P < .001) while sIgE/sIgG₄ ratios were consistently lower (P < .001). The ELIFAB assay was paralleled by low sIgE/sIgG₄ ratios in VIT patients, showing markedly higher allergen-blocking capacity (P < .001). An almost complete inhibition of the basophil response was seen in all patients treated with vespid venom, but not in those treated with bee venom. Four weeks after the sting, sIgE and sIgG₄ levels were increased in allergic and asymptomatically sensitized patients, but not in VIT patients.

CONCLUSION

Immunological responses after stings varied in bee and vespid venom-allergic patients. In patients under VIT, sIgE and sIgG₄ remained completely stable after sting challenges. Monitoring VIT efficacy was only possible in vespid venom allergy, and the sIgG₄ threshold for rVes v 5 had the highest sensitivity to confirm tolerance. The BAT inhibition test was the most reliable tool to confirm tolerance on an individual basis.

Maternal and neonatal outcomes in pregnant women with PCOS: comparison of different diagnostic definitions

STUDY QUESTION

Does the prevalence of adverse maternal and neonatal outcomes vary in women diagnosed with polycystic ovary syndrome (PCOS) according to different definitions?

SUMMARY ANSWER

A comparison of different criteria revealed that there is a substantial risk for perinatal complications in PCOS women, regardless of the used definition.

WHAT IS KNOWN ALREADY

Pregnant women with PCOS are susceptible to perinatal complications. At present, there are three main definitions for PCOS. So far, we are aware of only one study, which found that the elevated risk for complications varied widely depending on the different phenotypes and features but only considered a relatively small sample size for some of the phenotypes.

STUDY DESIGN, SIZE, DURATION

Retrospective matched cohort study.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Data of primiparous women with PCOS according to ESHRE/ASRM 2003 criteria and healthy controls giving birth to neonates ≥500 g were included. A total of 885 women were analysed: out of 177 women with PCOS, 85 (48.0%) met the National Institutes of Health (NIH) 1990 criteria, another 14 (7.9%) featured the additional phenotypes defined by The Androgen Excess and PCOS Society (AE-PCOS) 2006 criteria, 78 (44.1%) were classified as PCOS exclusively by the ESHRE/ASRM 2003 definition, and 708 represented the control group.

MAIN RESULTS AND THE ROLE OF CHANCE

The prevalence of adverse maternal (49.4 versus 64.3 versus 60.3%, P = 0.313) and neonatal (27.1 versus 35.7 versus 23.1%, P = 0.615) outcomes did not differ within the three PCOS groups (ESHRE/ASRM, NIH, AE-PCOS, respectively). Compared with healthy controls, the risk for maternal complications was increased in PCOS patients [odds ratio (OR) 2.57; 95% confidence interval (CI) 1.82-3.64; P < 0.001] while there was no difference in neonatal complications (OR 0.83; 95% CI 0.56-1.21; P = 0.343).

LIMITATIONS, REASONS FOR CAUTION

A limitation of our study is its retrospective design and the relatively small sample size, particularly in the AE-PCOS subgroup.

WIDER IMPLICATIONS OF THE FINDINGS

Since women with PCOS have, regardless of the used definition, a high risk of maternal and neonatal complications they should be informed and advised to follow regular checks in units where problems can be detected early to allow specialized care.

STUDY FUNDING/COMPETING INTERESTS

Marietta Blau Grant (Austrian Agency for International Cooperation in Education and Research; OeAD-GmbH) and mobility scholarship (Medical University of Graz).

Open bronchial stump post-pneumonectomy: findings on xenon-133 ventilation imaging

A 67-yr-old male status post right pneumonectomy for non-small cell lung cancer who later developed an open right bronchial stump underwent a ventilation-perfusion lung scan because of episodes of recurrent dyspnea suspected to be due to pulmonary embolism. Xenon-133 ventilation images showed both rapid entry into and later washout of activity from the air-filled portion of the right thoracic cavity. A wide-open bronchial stump, documented both at bronchoscopy and later autopsy, allowed the xenon gas to freely wash out from the thoracic cavity, resulting in a different imaging pattern than for a typical bronchopleural fistula, which is usually characterized by prolonged trapping of radioactive gas within the pleural space.