COVID-associated complications after reconstructive breast surgery: a retrospective cohort study.

PURPOSE: The COVID pandemic significantly influenced reconstructive breast surgery regimens. Many surgeries were cancelled or postponed. COVID entails not only respiratory, but also coagulative symptoms. It, therefore, potentially increases the risk of postoperative complications. The incidence of perioperative COVID infection and its influence on postoperative recovery after reconstructive breast surgery is still unknown. METHODS: This dual center retrospective cohort study included patients that underwent reconstructive breast surgery between March 2020 and July 2021. Post-mastectomy autologous or implant-based breast reconstruction (ABR; IBR), as well as post-lumpectomy oncoplastic partial breast reconstruction (PBR) were eligible. Patient data were extracted from electronic medical records. Data regarding COVID-19 infection was collected through a questionnaire. The primary outcome was complication rate. RESULTS: The ABR, IBR and PBR groups consisted of 113 (12 COVID-positive), 41 (2 COVID-positive) and 113 (10 COVID-positive) patients. In the ABR and PBR groups, postoperative complications occurred significantly more often in patients with perioperative COVID-infection. Especially impaired wound healing occurred significantly more often in the ABR and PBR breasts, but also at the donor site of ABR patients with perioperative COVID. CONCLUSION: Perioperative COVID-infection increases susceptibility to complicated wound healing after reconstructive breast surgery. A possible explanation lies in the dysregulation of haemostasis by the virus, and its direct effects on microvasculature. A hypercoagulable state results. We recommend to postpone elective breast surgery for 4-6 weeks after COVID-19 infection. Also, precautionary measures remain important to minimize the risk of perioperative COVID-19 infection.

No substantial excess all-cause mortality among cardiac implantable electronic device patients during the first COVID­19 lockdown in the Leiden area.

In the Netherlands, the coronavirus disease 2019 (COVID­19) pandemic has resulted in excess mortality nationwide. Chronic heart disease patients are at risk for a complicated COVID­19 course. The current study investigates all-cause mortality among cardiac implantable electronic device (CIED) patients during the first peak of the pandemic and compares the data to the statistics for the corresponding period in the two previous years. Data of adult CIED patients undergoing follow-up at the Leiden University Medical Centre were analysed. All-cause mortality between 1 March and 31 May 2020 was evaluated and compared to the data for the same period in 2019 and 2018. At the beginning of the first peak of the pandemic, 3,171 CIED patients (median age 70 years; 68% male; 41% ischaemic aetiology) were alive. Baseline characteristics of the 2019 (n = 3,216) and 2018 (n = 3,169) cohorts were comparable. All-cause mortality during the peak of the pandemic was 1.4% compared to 1.6% and 1.4% in the same period in 2019 and 2018, respectively (p = 0.84). During the first peak of the COVID­19 pandemic, there was no substantial excess mortality among CIED patients in the Leiden area, despite the fact that this is group at high risk for a complicated course of a COVID­19 infection. Strict adherence to the preventive measures may have prevented substantial excess mortality in these vulnerable patients.

The effect of the food matrix on in vivo immune responses to purified peanut allergens.

There is little knowledge about the factors that determine the allergenicity of food proteins. One aspect that remains to be elucidated is the effect of the food matrix on immune responses to food proteins. To study the intrinsic immunogenicity of allergens and the influence of the food matrix, purified peanut allergens (Ara h 1, Ara h 2, Ara h 3, or Ara h 6) and a whole peanut extract (PE) were tested in the popliteal lymph node assay (PLNA) and in an oral model of peanut hypersensitivity. In the PLNA, peanut proteins were injected into the hind footpad of BALB/c mice; in the oral exposure experiments C3H/HeOuJ mice were gavaged weekly with PE or allergens in the presence of cholera toxin (CT). Upon footpad injection, none of the allergens induced significant immune activation. In contrast, PE induced an increase in cell number, cytokine production, and activation of antigen-presenting cells. Furthermore, the presence of a food matrix enhanced the immune response to the individual allergens. Oral exposure to the purified allergens in the presence of CT induced specific IgE responses, irrespective of the presence of a food matrix. These results suggest that purified peanut allergens possess little intrinsic immune-stimulating capacity in contrast to a whole PE. Moreover, the data indicate that the food matrix can influence responses to individual proteins and, therefore, the food matrix must be taken into account when developing models for allergenic potential assessment.

Genetics of allergic disease.

Atopy can express itself as asthma, rhinitis and eczema. The presence of atopy can be assessed by increased levels of total serum IgE and specific IgE to common allergens, skin test positivity and increased numbers of peripheral blood eosinophils. Genetic studies indicate that multiple genes are involved in the pathogenesis of atopy and that different genes regulate the presence of increased levels of serum total IgE and specific IgE. Linkage of these traits to chromosomal regions likely to contain atopic susceptibility genes has been replicated in several studies. Genome-wide screens have identified several new chromosomal locations that are likely to contain atopic genes. These regions also contain candidate genes. Moreover, the available literature suggests that multiple, yet different genes may be involved in the translation of atopy to a distinct clinical phenotype. We anticipate that understanding of the genetic basis of atopy will lead to new therapeutic interventions and early diagnosis.