Study protocol for the St James's Hospital, Tallaght University Hospital, Trinity College Dublin Allied Researchers' (STTAR) Bioresource for COVID-19

Background: The current coronavirus disease 2019 (COVID-19) pandemic began in Ireland with the first confirmed positive case in March 2020. In the early stages of the pandemic clinicians and researchers in two affiliated Dublin hospitals identified the need for a COVID-19 biobanking initiative to support and enhance research into the disease. Through large scale analysis of clinical, regional, and genetic characteristics of COVID-19 patients, biobanks have helped identify, and so protect, at risk patient groups The STTAR Bioresource has been created to collect and store data and linked biological samples from patients with SARS-CoV-2 infection and healthy and disease controls. Aim: The primary objective of this study is to build a biobank, to understand the clinical characteristics and natural history of COVID-19 infection with the long-term goal of research into improved disease understanding, diagnostic tests and treatments. Methods: This is a prospective dual-site cohort study across two tertiary acute university teaching hospitals. Patients are recruited from inpatient wards or outpatient clinics. Patients with confirmed COVID-19 infection as well as healthy and specific disease control groups are recruited.  Biological samples are collected and a case report form detailing demographic and medical background is entered into the bespoke secure online Dendrite database. Impact: The results of this study will be used to inform national and international strategy on health service provision and disease management related to COVID-19. In common with other biobanks, study end points  evolve over time as new research questions emerge. They currently include patient survival, occurrence of severe complications of the disease or its therapy, occurrence of persistent symptoms following recovery from the acute illness and vaccine responses.

Changes in the multidisciplinary management of rectal cancer from 2009 to 2015 and associated improvements in short-term outcomes

AIM

Significant recent changes in management of locally advanced rectal cancer (LARC) include preoperative staging, use of extended neoadjuvant therapies and minimally invasive surgery (MIS). This study was aimed at characterizing these changes and associated short-term outcomes.

METHOD

We retrospectively analysed treatment and outcome data from patients with T3/4 or N+ LARC ≤ 15 cm from the anal verge who were evaluated at a comprehensive cancer centre in 2009-2015.

RESULTS

In total, 798 patients were identified and grouped into five cohorts based on treatment year: 2009-2010, 2011, 2012, 2013 and 2014-2015. Temporal changes included increased reliance on MRI staging, from 57% in 2009-2010 to 98% in 2014-2015 (P < 0.001); increased use of total neoadjuvant therapy, from 17% to 76% (P < 0.001); and increased use of MIS, from 33% to 70% (P < 0.001). Concurrently, median hospital stay decreased (from 7 to 5 days; P < 0.001), as did the rates of Grade III-V complications (from 13% to 7%; P < 0.05), surgical site infections (from 24% to 8%; P < 0.001), anastomotic leak (from 11% to 3%; P < 0.05) and positive circumferential resection margin (from 9% to 4%; P < 0.05). TNM downstaging increased from 62% to 74% (P = 0.002).

CONCLUSION

Shifts toward MRI-based staging, total neoadjuvant therapy and MIS occurred between 2009 and 2015. Over the same period, treatment responses improved, and lengths of stay and the incidence of complications decreased.

CD3ε Expression Defines Functionally Distinct Subsets of Vδ1 T Cells in Patients With Human Immunodeficiency Virus Infection

Human γδ T cells expressing the Vδ1 T cell receptor (TCR) recognize self and microbial antigens and stress-inducible molecules in a major histocompatibility complex-unrestricted manner and are an important source of innate interleukin (IL)-17. Vδ1 T cells are expanded in the circulation and intestines of patients with human immunodeficiency virus (HIV) infection. In this study, we show that patients with HIV have elevated frequencies, but not absolute numbers, of circulating Vδ1 T cells compared to control subjects. This increase was most striking in the patients with Candida albicans co-infection. Using flow cytometry and confocal microscopy, we identify two populations of Vδ1 T cells, based on low and high expression of the ε chain of the CD3 protein complex responsible for transducing TCR-mediated signals (denoted CD3ε^lo and CD3ε^hi Vδ1 T cells). Both Vδ1 T cell populations expressed the CD3 ζ-chain, also used for TCR signaling. Using lines of Vδ1 T cells generated from healthy donors, we show that CD3ε can be transiently downregulated by activation but that its expression is restored over time in culture in the presence of exogenous IL-2. Compared to CD3ε^hi Vδ1 T cells, CD3ε^lo Vδ1 T cells more frequently expressed terminally differentiated phenotypes and the negative regulator of T cell activation, programmed death-1 (PD-1), but not lymphocyte-activation gene 3, and upon stimulation in vitro, only the CD3ε^hi subset of Vδ1 T cells, produced IL-17. Thus, while HIV can infect and kill IL-17-producing CD4⁺ T cells, Vδ1 T cells are another source of IL-17, but many of them exist in a state of exhaustion, mediated either by the induction of PD-1 or by downregulation of CD3ε expression.

Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

Transmitted human immunodeficiency virus drug resistance in Europe is stable at around 8%. The impact of baseline mutation patterns on susceptibility to antiretroviral drugs should be addressed using clinical guidelines. The impact on baseline susceptibility is largest for nonnucleoside reverse transcriptase inhibitors.

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001.

Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0.

Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones.

Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected.

Goblet cell carcinoid neoplasm of the appendix: clinical and CT features

PURPOSE

To describe the clinical and CT imaging features of goblet cell carcinoid (GCC) neoplasm of the appendix.

METHODS AND MATERIALS

A computer search of pathology and radiology records over a 19-year period at our two institutions was performed using the search string "goblet". In the patients with appendiceal GCC neoplasms who had abdominopelvic CT, imaging findings were categorized, blinded to gross and surgical description, as: "Appendicitis", "Prominent appendix without peri-appendiceal infiltration", "Mass" or "Normal appendix". The CT appearance was correlated with an accepted pathological classification of: low grade GCC, signet ring cell adenocarcinoma ex, and poorly differentiated adenocarcinoma ex GCC group.

RESULTS

Twenty-seven patients (age range, 28-80 years; mean age, 52 years; 15 female, 12 male) with pathology-proven appendiceal GCC neoplasm had CT scans that were reviewed. Patients presented with acute appendicitis (n=12), abdominal pain not typical for appendicitis (n=14) and incidental finding (n=1). CT imaging showed 9 Appendicitis, 9 Prominent appendices without peri-appendiceal infiltration, 7 Masses and 2 Normal appendices. Appendicitis (8/9) usually correlated with typical low grade GCC on pathology. In contrast, the majority of Masses and Prominent Appendices without peri-appendiceal infiltration were pathologically confirmed to be signet ring cell adenocarcinoma ex GCC. Poorly differentiated adenocarcinoma ex GCC was seen in only a small minority of patients. Hyperattenuation of the appendiceal neoplasm was seen in a majority of cases.

CONCLUSIONS

GCC neoplasm of the appendix should be considered in the differential diagnosis in patients with primary appendiceal malignancy. Our cases demonstrated close correlation between our predefined CT pattern and the pathological classification.

Long-term neurological follow-up of HIV-positive patients diagnosed with syphilis

No cerebrospinal fluid (CSF) abnormalities are found in HIV-positive patients in long-term follow-up after standard syphilis treatment. Syphilis has been reported to have immunological effects on HIV infection and HIV is known to modulate both the manifestations of syphilis and the serological response to therapy. HIV-positive patients who had been diagnosed with and treated for syphilis prior to 2007 were identified. Patients were consented for lumbar puncture. Serum HIV viral load, CD4 count and CSF were recorded. Thirty-five patients with previously diagnosed and treated syphilis underwent lumbar puncture. Thirty-four patients had a normal neurological exam. Only one patient had an abnormal mean white cell count (10.7 cells per high-power field). The finding that those with previously diagnosed syphilis had normal CSF and clinical findings is reassuring and supports the practice of using standard syphilis therapy in HIV-positive patients.

Carpal tunnel release using local anaesthetic and a forearm tourniquet

Carpal tunnel release can be performed under general or local anaesthetic. However, many surgeons believe the upper arm tourniquet is not tolerated by the patient when awake. We use a forearm tourniquet for carpal tunnel decompression under local anaesthesia. The aim of this study is to assess patient tolerance of the technique. Between January 1st 1996 and December 31st 2000, 74 patients had carpal tunnel release performed using local anaesthesia. We sent a postal questionnaire to each, asking the patient to rate different aspects of the procedure. Fifty-eight patients replied (78% response). Forty-four of the respondents (76%) tolerated the tourniquet well, finding it to be 'no problem' or only 'mildly painful'. The same number reported they would prefer to have local anaesthesia again in the event of their requiring a similar operation on their hand. We believe carpal tunnel release using local anaesthetic and a forearm tourniquet is well tolerated by the patient.

Cervical Spine Loading Characteristics in a Cadaveric C5 Corpectomy Model Using a Static and Dynamic Plate

Anterior plates are used to increase the initial stability of anterior cervical spine fusions; however, plating has been suggested to cause graft stress shielding, leading to reduced fusion rates. The objectives of this study were to quantify the effects of graft size and plating (static versus dynamic) and the role of the posterior elements on load transmission in anterior cervical fusion. A C5 corpectomy was performed on six human cervical spines (C3-C7). An instrumented height-adjustable graft and dynamic cervical plate were used to measure axial load transmission. Each specimen underwent axial compressive testing with dynamic and static plate configurations, optimal and undersized graft heights, and posterior elements intact and removed. Dynamic plating allowed significantly more load transmission by the graft, particularly in the undersized graft configuration. The posterior elements play a significant role in load transmission.

Severe osteopenia with recurrent fractures after bone marrow transplant for Wiskott-Aldrich syndrome: a case report

Wiskott-Aldrich syndrome (WAS) is a rare inherited disorder characterised by thrombocytopenia, eczema, and immunodeficiency. Bone marrow transplantation (BMT) is a well-established modality of treatment now routinely used and often curative. We report the case of a boy who developed osteopenia and sustained multiple long-bone fractures over a 5-year period after bone marrow transplant for WAS. The femora and tibiae of both lower limbs were involved with a clinical presentation similar to osteogenesis imperfecta. After commencing calcitriol treatment at the age of 8 years, the patient has not sustained any further fractures. He is now 11 years old. Although short-term changes in bone metabolism after BMT have been documented, the occurrence of repeated fractures associated with osteopenia has not been previously reported.

The biomechanical evaluation of polyester as a tension band for the internal fixation of patellar fractures

We use a braided polyester suture in place of cerclage wire in tension band fixations. The objective of this study was to test the biomechanical properties of this technique. Sixteen cadaveric patellae were fractured and repaired by modified tension band fixation. Eight were fixed using eighteen gauge stainless steel wire as a tension band and eight using braided polyester. All specimens were subjected to tensile testing. Polyester was 75.0% as strong as wire. For dynamic testing, the patellae of seven cadaveric knees were fractured and then fixed with polyester tension bands. These were mounted in a device capable of extending the knees from 90 degrees to neutral against an applied force. None of the fixations failed. Three of the specimens fixed using 18 gauge stainless steel wire were compared with three fixed using polyester over 2000 cycles of knee flexion and extension. Polyester performed as well as wire. We conclude that polyester is an acceptable alternative to wire in tension band fixation.