Examining the role of community health workers amid extreme weather events in low- and middle-income countries: a scoping review.

OBJECTIVES: The increased frequency and severity of extreme weather events (EWEs) have underscored the need to strengthen climate-resilient health systems and capacity. Community health workers (CHWs) are integral health systems actors with the potential to protect and improve population health in a changing climate. The aim of this review was to synthesize the literature on the roles of CHWs amid EWEs in low- and middle-income countries, the barriers and facilitators to implement these roles, and program supports to strengthen CHW capacity and health system functions. STUDY DESIGN: Scoping review. METHODS: Four academic databases and gray literature published between January 2000 and June 2023 were searched. Data were thematically analyzed using a deductive-inductive approach guided by the World Health Organization's (WHO's) Operational framework for building climate-resilient health systems. RESULTS: Thirty sources were included. Amid EWEs, CHW roles included: 1) delivery of diagnostic, treatment, and other clinical services; 2) support with access, utilization, or navigation of health services and/or referrals; 3) community education and health promotion; 4) data collection and health surveillance; 5) psychosocial supports; and 6) weather-related health emergency response. Facilitators and barriers to the provision of CHW supports amid EWEs were categorized within WHO's building blocks of health systems. Considerations for strengthening CHW programs to enhance climate-resilient health systems are also discussed. CONCLUSIONS: CHWs are uniquely positioned to provide health-related supports amid EWEs that extend to emergency preparedness and response to climate-health challenges. These efforts can contribute to the community and health systems resilience to climate change.

Ocular co-morbidities in patients with atopic dermatitis - a cross-sectional study from a tertiary referral hospital, Malaysia.

INTRODUCTION: Atopic dermatitis (AD) is a chronic relapsing pruritic inflammatory skin disease that commonly occurs among children as well as adults. AD patients were reported to have high prevalence of ocular manifestations, which may be due to the disease nature or drug complications. This study aimed to determine the prevalence of ocular manifestations in patients with AD. MATERIALS AND METHODS: Eighty patients who fulfilled the UK Working Party's Diagnostic Criteria for Atopic Dermatitis were included in the cross-sectional study. A standardized case report form was formulated to collect the demographic data and disease profile of the participants. AD severity was evaluated using the EASI and SCORAD score. All patients underwent a complete ophthalmological evaluation. RESULTS: The prevalence of ocular manifestations among the patients with AD was 48.8%. Fifty-four (67.5%) patients had facial dermatitis and 37 (46.2%) showed periorbital signs. The mean AD disease duration was 10.99 ± 11.20 years. Majority of the patients had mild to moderate AD. The most frequent ocular manifestation was allergic conjunctivitis (18.75%) followed by cataract (8.75%) and ocular hypertension (8.75%). Among the patients with ocular manifestations, 27 (69.2%) patients regularly applied topical corticosteroids on the face. The use of systemic corticosteroids was seen in 19 (42.2%) patients. Prolonged AD duration was significantly associated with the development of ocular manifestations. CONCLUSIONS: Nearly half of the patients with AD were complicated with ocular disease regardless of the AD severity, facial dermatitis and presence of periorbital signs. Long disease duration is associated with ocular manifestations, especially steroid related complications.

Immunoglobulin G4-related disease in Hong Kong: clinical features, treatment practices, and its association with multisystem disease.

INTRODUCTION: Immunoglobulin G4-related disease remains an under-recognised and evolving disease. Local data are sparse and previous publications have been limited to individual case reports or case series only. We conducted this study to review the clinical features, treatment practices, and factors associated with multisystem involvement in Hong Kong. We described the clinical features and treatment modalities of the largest cohort of immunoglobulin G4-related disease in our locality thus far. METHODS: We retrospectively evaluated all patients with immunoglobulin G4-related disease between January 2003 and December 2015 in Queen Mary Hospital and combined this with patient data extracted from previous local publications. We analysed the clinical features, treatment practices, and factors associated with the number of organ systems involved. RESULTS: A total of 104 patients (55 from Queen Mary Hospital and 49 from literature review) were identified. Patients were predominantly older men (mean [standard deviation] age, 61.9 [12.7] years; male-to-female ratio=3:1) and 94.4% had elevated pre-treatment serum immunoglobulin G4 levels. Hepatobiliary and pancreatic system (40.4%), salivary gland (33.7%), lymph node (29.8%), and eye (19.2%) were the most common organ systems involved. Lymphadenopathy was associated with glucocorticoid use (odds ratio=2.65; 95% confidence interval, 1.08-6.54; P=0.034). Pre-treatment serum immunoglobulin G4 levels correlated with the number of organ systems involved (ß=0.347; P=0.004) and, specifically, more associated with patients having salivary gland involvement than those without (mean, 1109 mg/dL vs 599 mg/dL; P=0.012). CONCLUSION: We identified pre-treatment serum immunoglobulin G4 to be associated with multisystem disease, especially with salivary gland involvement, highlighting its potential for disease prognostication and monitoring. Increased physician awareness and multidisciplinary efforts are required for early diagnosis and optimal management of this masquerading disease.

Implications of attendance patterns in Northern Ireland for abdominal aortic aneurysm screening.

INTRODUCTION: Evidence supports the introduction of an abdominal aortic aneurysm (AAA) screening programme. The aims of this study were to estimate future disease patterns and to determine the effect of the proportion attending on the programme's cost-effectiveness. PATIENTS AND METHODS: The results of the local AAA screening programme were reviewed. Ultrasonic infrarenal aortic diameter of 30 mm was considered aneurysmal. Projected population numbers from the Department of Health and current disease prevalence were used to estimate future number of potential patients. The Multi-centre Aneurysm Screening Study (MASS) Markov model was used to calculate an incremental cost-effectiveness ratio (ICER) and 95% uncertainty intervals (UI), using a 30-year time horizon and 3.5% per annum discount, to determine the effect of attendance. RESULTS: Men were recruited from August 2004 to May 2010. 13316 were invited for a scan and 5931 (44.5%) attended. 321 AAA were diagnosed, giving a prevalence of 5.4%, while 27 large AAA (0.46%) were repaired. The annual incidence of AAA until 2021 will range from 441 to 526, with an incidence of 40-48 large AAA, with both showing a gradual increase with time. Using this attendance rate, the ICER was calculated at £2350 per life-year gained (95% UI: £1620-£4290), or £3020 per quality-adjusted life-year gained (95% UI: £2080-£5500). CONCLUSIONS: The prevalence of disease in this local AAA screening was similar to other studies. The low attendance will result in many AAA being missed, but will not impact greatly on the long-term cost-effectiveness.

Interleukin 1 production during accessory cell-dependent mitogenesis of T lymphocytes.

We have studied the control and significance of IL-1 production in human leukocyte cultures during accessory cell-dependent, T lymphocyte mitogenesis using sensitive bioassays and immunolabeling techniques. In primary antigen-dependent systems like the MLR, IL-1 production was not detected in accessory cells (monocytes, dendritic cells) or T cells, suggesting that it is not an early product in these responses. However, monocytes could be induced to make IL-1 after interacting with sensitized antigen-specific T cells. Both alloreactive T cell clones or freshly prepared lymphoblasts induced IL-1 provided the monocytes carried the HLA-DR antigens to which the T cells were initially sensitized. Even in these circumstances, dendritic cells and B cells failed to make IL-1. The mechanism whereby activated T cells induce IL-1 in monocytes was explored. Supernatants from cocultures of monocytes and T cells or several recombinant cytokines induced little or no IL-1. A more potent antigen independent pathway of IL-1 induction was identified. IL-1 could be induced in third-party HLA-DR nonspecific monocytes in cocultures of alloreactive T cell clones or blasts and HLA-DR-specific dendritic cells. The induction was factor independent since dendritic cells and T blasts placed in a chamber separate from third-party monocytes by a semipermeable membrane did not induce monocyte IL-1. These results suggest that a cell contact mechanism rather than an IL-1-inducing factor leads to IL-1 production. The role of IL-1 in T cell proliferation was tested with a polyclonal anti-IL-1 antibody. The antibody failed to block the proliferation of primary T cells, or alloreactive T cell clones and blasts stimulated with HLA-specific monocytes or dendritic cells, even though IL-1 in the medium was neutralized.

Persistence of memory CD8 T cells in MHC class I-deficient mice.

An understanding of how T cell memory is maintained is crucial for the rational design of vaccines. Memory T cells were shown to persist indefinitely in major histocompatibility complex (MHC) class I-deficient mice and retained the ability to make rapid cytokine responses upon reencounter with antigen. In addition, memory CD8 T cells, unlike naïve cells, divided without MHC-T cell receptor interactions. This "homeostatic" proliferation is likely to be important in maintaining memory T cell numbers in the periphery. Thus, after naïve CD8 T cells differentiate into memory cells, they evolve an MHC class I-independent "life-style" and do not require further stimulation with specific or cross-reactive antigen for their maintenance.

Identification of immunostimulatory dendritic cells in the synovial effusions of patients with rheumatoid arthritis.

Dendritic cells in the circulation are leukocytes that are rich in Ia antigens and that actively stimulate T cell replication. We have identified dendritic cells in the joint effusions of patients with rheumatoid arthritis. By phase-contrast and immunofluorescence microscopy, synovial mononuclear cells contained 1-5% dendritic profiles that were rich in HLA-DR and DQ, had small amounts of C3bi receptor, and lacked a battery of monocyte and lymphocyte markers. These dendritic cells could be enriched to 60-80% purity by cytolytic depletion of monocytes and lymphocytes with a group of monoclonal antibodies (MAb) and complement. By transmission electron microscopy, the dendritic cell processes were bulbous in shape and lacked organelles. The cytoplasm had few lysosomes or endocytic vacuoles but contained a well-developed smooth reticulum that was comparable to that previously described in the Ia-rich interdigitating cells of lymphoid tissues. The growth of sodium periodate-modified T lymphocytes was used as a rapid quantitative assay of accessory cell function. Synovial mononuclear cells were some ten times more active than normal blood cells. Treatment with alpha-Ia MAb and complement ablated stimulatory function. In contrast, removal of monocytes (MAb, 3C10) or monocytes and B (MAb, BA-1) plus T (MAb, OKT3, or T101) lymphocytes did not significantly alter total activity, and the function per viable cell increased four- to eightfold. We conclude that rheumatoid arthritis synovial fluids contain cells that are comparable in function, phenotype, and structure to blood dendritic cells, although the frequency (1-5%) is 10 times greater in joints. The reason for their accumulation in the articular cavity is not known, but dendritic cells may be important in perpetuating the joint inflammation characteristic of this disease.

Altered aging-related thymic involution in T cell receptor transgenic, MHC-deficient, and CD4-deficient mice.

During aging in mice and humans, a gradual decline in thymus integrity and function occurs (thymic involution). To determine whether T cell reactivity or development affects thymic involution, we compared the thymic phenotype in old (12 months) and young (2 months) mice transgenic for rearranged alphabeta or beta 2B4 T cell receptor (TCR) genes, mice made deficient for CD4 by gene targetting (CD4(-/-)), mice made deficient for major histocompatibility complex (MHC) class I (beta2M-/-) or class II genes (A(beta)(b-/-) on C57Bl/6 background) or both. The expected aging-related reductions in thymic weights were observed for all strains except those bearing disruption of both class I and class II MHC genes. Therefore, disruption of MHC class I and class II appeared to reverse or delay aging-related thymic atrophy at 12 months. Immunohistochemical analysis of aging-associated alterations in thymic morphology revealed that TCR alphabeta transgenes, CD4 disruption, and MHC class II disruption all reduced or eliminated these changes. All strains examined at 12 months showed alterations in the distribution of immature thymocyte populations relative to young controls. These results show that aging-associated thymic structural alterations, size reductions, and thymocyte developmental delays can be separated and are therefore causally unrelated. Furthermore, these results suggest that the T cell repertoire and/or its development play a role in aging-related thymic involution.

Accentuated oxidative stress following reperfusion injury in diabetic rats.

BACKGROUND: This study investigates whether diabetes mellitus accentuates hind limb ischemia-reperfusion injury. METHODS: Male Wistar rats rendered diabetic (n=40) following injection of streptozotocin were compared to non-diabetic control rats (n=30). Each group was divided into sham, 4 hrs of hind limb ischemia, 4 hrs of ischemia followed by 10, 30 or 60 min of reperfusion. Plasma concentrations of an end-product of lipid peroxidation [malondialdehyde (MDA)] and antioxidants (vitamins A and E) were measured together with the resting membrane potential (RMP) of the gastrocnemius muscle. RESULTS: Following reperfusion, the diabetic group showed greater and more persistent elevation of MDA and greater reduction of antioxidants. This was associated with reduction in the RMP only in the diabetic group. There was significant correlation between MDA level and the RMP in both groups of animals. CONCLUSIONS: These results indicate that oxidative stress following reperfusion injury is greater in the presence of diabetes mellitus. This may lead to a decrease in the RMP and increase in the vascular permeability, which may be associated with more complications.

Extraperitoneal approach reduces intestinal and renal dysfunction in elective abdominal aortic aneurysm repair.

BACKGROUND: Intestinal mucosal barrier dysfunction observed in patients undergoing transperitoneal abdominal aortic aneurysm (AAA) repair may contribute to the development of the systemic inflammatory response syndrome and dysfunction of various organs. The aim of this study is to investigate whether an extraperitoneal approach reduces intestinal mucosal barrier and renal dysfunction in elective infrarenal AAA repair. METHODS: Twenty patients admitted for elective infrarenal AAA repair were randomized into either the transperitoneal approach (n=10) or the extraperitoneal approach (n=10). Intestinal permeability was measured preoperatively, and at day 1 and day 3 after surgery using the lactulose/mannitol test by calculating the differential urinary excretion ratio of the two sugars after oral administration. Renal dysfunction was assessed by measuring the urinary albumin/creatinine ratio (ACR) at the same time points. RESULTS: Intestinal permeability was significantly increased in the transperitoneal group at day 1 [0.124+/-0.035 (mean+/-s.e.m.)] compared to the preoperative level (0.020+/-0.003), (p=0.001) and to the extraperitoneal group at day 1 (0.025+/-0.008), (p<0.05) which showed no change in comparison with the preoperative level (0.020+/-0.003). The ACR was also significantly increased in the transperitoneal group at day 1 (16.69+/-5.12) compared to the preoperative level (5.71+/-2.89), (p<0.05) and to the extraperitoneal group at day 1 (4.33+/-1.49), (p<0.05) which showed no significant change at any of the times examined. No correlation was observed between the lactulose/mannitol ratio and the albumin/creatinine ratio, or between age, operating time, aortic clamping time, amount of blood lost or blood transfused. CONCLUSIONS: These results support the suggestion that minimising intestinal manipulation using an extraperitoneal approach in AAA repair preserves intestinal mucosal barrier and renal glomerular functions.

Anaesthetic clinical indicators in public hospitals providing anaesthetic care in Hong Kong: prospective study.

OBJECTIVES: To assess the quality of anaesthetic services as defined in the six anaesthetic clinical indicators against preset standards and to identify risk factors for adverse events in the recovery room. DESIGN: Prospective study. SETTING: All public hospitals providing anaesthetic care in Hong Kong. PATIENTS: Eighteen thousand, seven hundred and fifty-nine patients receiving elective or emergency anaesthesia administered by anaesthetists from June 1998 to July 1998. MAIN OUTCOME MEASURES: Patient demographics, American Society of Anesthesiologists status, category and nature of operation, presence of preoperative anaesthetic visit in ward, type of anaesthesia, reasons for a recovery room stay of more than a 2-hour duration, intubation to relieve respiratory distress in the recovery room, presence of hypothermia in the recovery room for operations lasting more than 2 hours, and dental or ocular injuries attributable to anaesthesia. RESULTS: There are two major findings from this study. Firstly, a high incidence of hypothermia in the recovery room was reported. Secondly, a greater risk of prolonged stay in the recovery room was identified for patients older than 65 years, major operations, and anaesthetic techniques using combined general and regional anaesthesia. CONCLUSION: The six anaesthetic clinical indicators reflected the provision of anaesthetic care in public hospitals in Hong Kong. Good compliance to the preset standard of the anaesthetic clinical indicators was achieved during the study period.

Acute pain services in Hong Kong: facilities, volume, and quality.

Acute pain services in public hospitals in Hong Kong were studied. Audit data on the volume and quality of acute pain services were collected prospectively from 1997 to 1999, and data on related facilities were collected in 2000. About 20% of patients undergoing a major operation received an acute pain service; of these, 78.6% were satisfied with the treatment provided. In 2000, 86% (18/21) of hospitals providing anaesthetic services were running an acute pain service. Staffing was better in hospitals providing a high volume of acute pain services, ranging from a full-time specialist anaesthesiologist assisted by a half-time trainee to a half-time specialist assisted by a full- or half-time trainee. However, only four hospitals were staffed with pain nurses. In total, 57% of patients received intravenous patient-controlled analgesia and 32% epidural analgesia. The mean duration of acute pain service treatment was 3.1 days. Currently anaesthesiologist-based acute pain services take care of a limited number of patients. To expand the coverage, there should be a move towards an anaesthesiologist-led, pain nurse-based, acute pain service. The present shortage of pain nurses should be addressed.

The impact of endovascular repair of ruptured abdominal aortic aneurysm on the gastrointestinal and renal function.

Introduction. Systemic effects of ruptured abdominal aortic aneurysm (rAAA) may be altered by the mode of surgery. This study aimed to determine systemic effects of endovascular aneurysm repair (EVAR) compared to open repair (OR). Patients and Methods. Consecutive patients with rAAA were repaired by OR or EVAR according to computerised tomographic (CT) findings. Renal function was monitored by estimated glomerular filtration rate (eGFR), serum urea and creatinine, and urinary albumin creatinine ratio (ACR). Hepatic function was assessed postoperatively for 5 days. Intestinal function was determined by the paracetamol absorption test. Intestinal permeability was assessed by urinary lactulose/mannitol ratio. Results. 30 rAAA patients were included. Fourteen had eEVAR and sixteen eOR. Serum urea were higher in eOR, while creatinine was similar between groups. Hepatic function showed no intergroup difference. Paracetamol absorption was increased in eEVAR group at day 3 compared to day 1 (P = 0.03), with no similar result in eOR (P = 0.24). Peak lactulose/mannitol ratio was higher in eOR (P = 0.03), with higher urinary L/M ratio in eOR at day 3 (P = 0.02). Clinical intestinal function returned quicker in eEVAR (P = 0.02). Conclusion. EVAR attenuated the organ dysfunction compared to open repair. However, a larger comparative trial would be required to validate this. The clinical trial is registered with reference number EUDRACT: 2013-003373-12.

The inflammatory response to ruptured abdominal aortic aneurysm is altered by endovascular repair.

Introduction. Ruptured abdominal aortic aneurysm (rAAA) causes a significant inflammatory response. The study aims to investigate this response following endovascular and open repair of ruptured AAA. Patients and Methods. Consecutive rAAA patients had either endovascular aneurysm repair (EVAR) or open repair (OR). Blood samples were taken for cytokines, lipid hydroperoxides (LOOH), antioxidants, and neutrophil elastase/ α 1-anti-trypsin complexes (NE/AAT) before surgery, 6 hours after clamp release and 1, 3, 5 days postoperatively. Results. 30 patients were included in the study, with 14 undergoing eEVAR and 16 eOR, with comparable baseline comorbidities, age, and parameters. IL-6 peaked higher in eOR patients (P = 0.04), while p75TNFr was similar between groups except at day 5 (P = 0.04). The NE/AAT concentrations were higher in eOR patients (P = 0.01), particularly in the first postoperative day, and correlated with blood (r = 0.398, P = 0.029) and platelet (r = 0.424, P = 0.020) volume transfused. C-reactive protein rose and lipid hydroperoxide fell in both groups without significant intergroup difference. Vitamins C and E, lycopene, and ß -carotene levels were similar between groups. Conclusion. EVAR is associated with lower systemic inflammatory response compared to OR. Its increased future use may thereby improve outcomes for patients.

A carotid artery aneurysm with a twist: case report and review.

BACKGROUND: Since their original description in 1687, aneurysms of the extracranial internal carotid artery (ICA) remain rare and account for less than 2% of all carotid operations (Zwolak et al. in: J Vasc Surg 1:415-422, 1984; El-Sabrout, Cooley in: J Vasc Surg 31:702-712, 2000). Cerebrovascular morbidity and mortality rates remain high without intervention (Zwolak et al. in: Vasc Surg 1:415-422, 1984). CASE REPORT: We report an unusual case of a saccular extracranial ICA aneurysm associated with kinking of the ICA and highlight the potential complications and risks associated with such an extreme anatomical deformation. CONCLUSION: Extracranial ICA aneurysm can be associated with unusual anatomical variations which can lead to unstable clinical symptomatology due to the variable presence of atherosclerotic material. Despite advances in diagnosis and treatment, surgical repair is not without risks and patients need to be informed of the potential complications.

Optimal management of peripheral arterial disease for the non-specialist.

Peripheral arterial disease (PAD) now affects approximately 20% of adults older than 55 years to an estimated total of 27 million people in the Western World. The aim of this paper is to describe the medical management of PAD for the non-vascular specialist, particularly general practitioners, where PAD has now been included in the Northern Ireland Department of Health's Primary Care Service Framework (Directed Enhanced Service).

Seroprevalence of antibody to pandemic influenza A (H1N1) 2009 among healthcare workers after the first wave in Hong Kong.

During the first wave of an influenza pandemic prior to the availability of an effective vaccine, healthcare workers (HCWs) may be at particular risk of infection with the novel influenza strain. We conducted a cross-sectional study of the prevalence of antibody to pandemic influenza A (H1N1) 2009 (pH1N1) among HCWs in Hong Kong in February-March 2010 following the first pandemic wave. Sera collected from HCWs were tested for antibody to pH1N1 influenza virus by viral neutralisation (VN). We assessed factors associated with higher antibody titres, and we compared antibody titres in HCWs with those in a separate community study. In total we enrolled 703 HCWs. Among 599 HCWs who did not report receipt of pH1N1 vaccine, 12% had antibody titre ≥1:40 by VN. There were no significant differences in the age-specific proportions of unvaccinated HCWs with antibody titre ≥1:40 compared with the general community following the first wave of pH1N1. Under good adherence to infection control guidelines, potential occupational exposures in the hospital setting did not appear to be associated with any substantial excess risk of pH1N1 infection in HCWs. Most HCWs had low antibody titres following the first pandemic wave.