Infection In Old Age Research Articles

Systemic infection in aged mice causes upregulation of crystallin alpha A in the RPE/choroid

Aging changes the responsiveness of our immune defense, and this decline in immune reactivity plays an important role in the increased susceptibility to infections that marks progressing age. Aging is also the most pronounced risk factor for development of age-related macular degeneration (AMD), a disease that is characterized by dysfunctional retinal pigment epithelial (RPE) cells and loss of central vision. We have previously shown that acute systemic viral infection has a large impact on the retina in young mice, leading to upregulation of chemokines in the RPE/choroid (RPE/c) and influx of CD8 T cells in the neuroretina. In this study, we sought to investigate the impact of systemic infection on the RPE/c in aged mice to evaluate whether infection in old age could play a role in the pathogenesis of AMD. We found that systemic infection in mice led to upregulation of genes from the crystallin family in the RPE/c from aged mice, but not in the RPE/c from young mice. Crystallin alpha A (CRYAA) was the most upregulated gene, and increased amounts of CRYAA protein were also detected in the aged RPE/c. Increased CRYAA gene and protein expression has previously been found in drusen and choroid from AMD patients, and this protein has also been linked to neovascularization. Since both drusen and neovascularization are important hallmarks of advanced AMD, it is interesting to speculate if upregulation of crystallins in response to infection in old age could be relevant for the pathogenesis of AMD.

Association of scrub typhus with incidence of dementia: a nationwide population-based cohort study in Korea

BackgroundScrub typhus is a mite-borne infectious rickettsial disease that can occur in rural and urban areas, with an especially high prevalence in older populations. This disease causes systemic vasculitis that can invade the central nervous system. Considering these characteristics, here we examined whether scrub typhus was associated with the occurrence of dementia, using large population-based cohort data.MethodThis population-based cohort study enrolled patients aged 60–89 years using data from the Health Insurance Review and Assessment database of South Korea between 2009 and 2018. We defined scrub typhus and dementia using International Classification of Diseases, Tenth Edition diagnostic codes. The control group was stratified according to age and sex at a ratio of 1:5 to the case group in the study population. The index date was set after 90 days beyond the date of the scrub typhus diagnosis, while the observation period was from the time of the index appointment to December 31, 2020. The primary outcome was newly diagnosed dementia. The secondary outcome was dementia classification, such as Alzheimer’s disease, vascular dementia, and other. All analyses were conducted by matching age, gender, and comorbidity.ResultsDuring the observation period, 10,460 of 71,047 (14.7%) people who had a history of scrub typhus versus 42,965 of 355,235 (12.1%) people in the control group, that is, with no history of scrub typhus, were diagnosed with dementia (adjusted hazard ratio, 1.12; 95% confidence interval, 1.10–1.15, p < 0.001). The Kaplan–Meier curves for time to cumulative incidence of dementia showed that the dementia incidence in both groups increased over time, while individuals with a past history of scrub typhus had a higher incidence of dementia than the control group. Second, the risk of Alzheimer’s disease was significantly higher among patients with a history of scrub typhus (adjusted hazard ratio, 1.15; 95% confidence interval 1.13–1.18, p < 0.001).ConclusionIn conclusion, a history of scrub typhus infection in old age is significantly associated with an increase in dementia, especially Alzheimer’s disease. Our results suggest that prevention and appropriate treatment of scrub typhus should be emphasized as a dementia prevention measure.

Epidemiological, Clinical and Laboratory study of Canine Dermatophytosis in Baghdad Governorate, Iraq

The aim of the present study was to isolate and identify of the pathogenic fungi of canine dermatophytosis in Baghdad governorate Iraq, also study the epidemiology and describe the clinical signs of dermatophytosis, from January 2018 till December 2018. Out of 653 dogs 165 (25.3%) were with dermatomycoses and 103 (62.42%) dogs with dermatophytosis. The mycological diagnosis were conducted by direct microscopy and by culture the specimens on each sabouraud dextrose agar supplemented with chloramphenicol and cyclohxemide and dermatophytes test media. The identified dermatophytes were represented Microsporum sp.(80.6%) appeared Microsporum canis (87.9%); M. audounii (8.4% );M. gypseum (3. 6 %) and Trichophyton spp (19.4%) in which divided between Trichophyton ruburum (60.0 %) and T. terrestre (40.0%). Microsporum canis and Trichophyton ruburum were the most common species isolated (87.9%),(60.0 %) respectively. The overall prevalence of dermatomycosis and dermatophytosis from various parts region of Baghdad city were Al Karkh district (32.0%), (64.6%) and Al Rusafa district (22.4%), (60.4%) respectively. Moreover, a higher percentage of infection in young age 55 of 84 (65.47%) and lower infection in old age 8 of 18 (44.44%) with significant difference at P&lt; 0.05. The effect of breeds on the prevalence of canine mycosis show high percentage of infection in German shepherd dog (47.96%) and lower infection in Bulldog breed (10.63%) as well as, high prevalence of dermatophytosis recorded in Rottweiler (100%), Pomeranian (83.3%) and lower prevalence (40.0 %) in each of Boxer and local dog breed. The relation of hair coat showed significantly high percentage of infection in long hair dogs (69.0%) than short hair coat (48.0%). There were no significant difference between the sex and habitat but, recorded a high (%) in shelters habitat (67.19%) and low (%) in plantation habitat (56.25%). The prevalence of infection was showed no signficantly high percentage of infection in cold climate winter (67.74%) in which low temperature and high humidity while low percentage of infection in dry climate autumn (44.4%). In addition the effect of season on the prevalence of dermatophytosis recognized by a higher (%) of infection in cold weather, winter (67.74%) and lower infection in dry weather, autumn (50.0%). Other dermatomycosis isolated were Chrysosporium Nannizziopsis dermatitidis (9.1%); Malassezia pacydermatis (7.9 %) and saprobe fungi from domestic dogs represented by Alternaria alternate (21.4%); Aspergillus spp (60.7%); Aspergillus flavus (25.9%); Aspergillus fumigatus (28.2%); Aspergillus niger (23.5 %); Aspergillus nidulans (22.4 %); Penicillium sp. (4.3%); Curvularia sp (3.6%) and Rhizopus sp (2.1%).

Understanding HIV-related stigma in older age in rural Malawi

The combination of HIV- and age-related stigma exacerbates prevalence of HIV infection and late diagnosis and initiation of anti-retroviral therapy among older populations (Moore, 2012; Richards et al. 2013). Interventions to address these stigmas must be grounded in understanding of situated systems of beliefs about illness and older age. This study analyses constructions of HIV and older age that underpinned the stigmatisation of older adults with HIV in rural Balaka, Malawi. It draws on data from a series of in-depth interviews (N = 135) with adults aged 50–∼90 (N = 43) in 2008–2010. Around 40% (n = 18) of the sample had HIV.Dominant understandings of HIV in Balaka pertained to the sexual transmission of the virus and poor prognosis of those infected. They intersected with understandings of ageing. Narratives about older age and HIV in older age both centred on the importance of having bodily, moral and social power to perform broadly-defined “work”. Those who could not work were physically and socially excluded from the social world. This status, labelled as “child-like”, was feared by all participants.In participants’ narratives, growing old involves a gradual decline in the power required to produce one’s membership of the social world through work. HIV infection in old age is understood to accelerate this decline. Understandings of the sexual transmission of HIV, in older age, imply the absence of moral power and in turn, loss of social power. The prognosis of those with HIV, in older age, reflects and causes amplified loss of bodily power. In generating dependency, this loss of bodily power infantilises older care recipients and jeopardises their family’s survival, resulting in further loss of social power. This age-and HIV-related loss of power to produce social membership through work is the discrediting attribute at the heart of the stigmatisation of older people with HIV.

Cohort Profile: The Bambui (Brazil) Cohort Study of Ageing

Ageing of the population is the most important demographic change facing many countries around the world. The speed of demographic ageing in Latin American and the Caribbean, however, will be unprecedented in comparison with Western European and North American countries. This demographic change will generate populations with large numbers of elderly who at some time in their lives have been exposed to infectious diseases. Infections may affect ageing in different ways. Most important postulated mechanisms include enhanced inflammation, pathogen-dependent tissue destruction or accelerated cellular ageing through increased turnover. Most epidemiological studies of ageing have, understandably, focused on non-communicable diseases and related conditions. To our knowledge, no previous population-based cohort study had examined the consequences of the double burden of non-communicable diseases and a parasitic chronic infection in old age. Chagas disease, which is caused by the protozoan Trypanosoma cruzi, is endemic in Latin American countries, with about 8 million people infected. As a consequence of immigration from endemic countries, Chagas disease is an emerging issue in North America and Europe, and an example in the era of globalization of how infectious diseases extend beyond endemic areas. Chagas disease is related to poor socio-economic circumstances in early life. In endemic areas, the main source of infection is a bloodsucking triatomine insect that colonizes poor households. Most individuals in these areas acquire the infection at <20 years of age, and 30% develop chronic chagasic cardiomyopathy. The ageing of the population, together with a cohort effect observed in endemic areas where the household insect transmission has been interrupted, will lead to increases in the number of older adults who are already infected by T. cruzi. The main objective of the Bambui Cohort Study of Ageing is to examine the separate and joint effects of chronic T. cruzi infection and non-communicable diseases on health outcomes in old age.

Hepatitis C Virus Infection in the Elderly

Hepatitis C virus (HCV) infection frequently occurs in elderly individuals, with a prevalence in individuals aged >60 years of up to approximately 40%. Although progression to cirrhosis is accelerated and occurs more frequently in patients who acquire the infection in old age, this outcome is often not seen because most elderly infected patients acquired HCV when they were young. Data on progression of HCV infection to cirrhosis and eventually to hepatocellular carcinoma are often derived from studies of HCV-infected individuals who present or are referred to hospitals, and which are therefore likely to overestimate the seriousness of the disease; indeed, population-based studies indicate that in many elderly individuals the disease is asymptomatic and runs a fairly benign course. Treatment is based on use of pegylated interferon-alpha and ribavirin, and is overall less effective and more toxic in the elderly. Therefore, treatment should be carefully considered on an individual basis and proposed only in patients up to the age of 75 years with a significant risk of progression of liver disease, no serious co-morbidities and good life expectancy. All treated patients should be followed long term in order to assess the influence of therapy on the evolution of liver disease (decompensated cirrhosis, hepatocellular carcinoma) and survival. It is hoped that liver biopsy, which is still required in order to assess prognosis appropriately, will be replaced in the future by less invasive methods based on combinations of biochemical markers of fibrosis and/or transient elastography, and that newer and less toxic orally administered drugs for HCV infection will become available.

Downward Shift in Serum IgM with Helicobacter pylori Seropositivity

Objective: To determine whether Helicobacter pylori infection is associated with premature immune ageing, with respect to circulating immunoglobulins.Methods: Serum immunoglobulin classes andH. pylori anti-urease antibody were measured in 205 subjects (aged 30–89 years), obeying inclusion/exclusion criteria.Results: IgM decreased (P<0.001) by 0.9 (95% C.I. 0.3, 1.4)% per year, H. pylori seropositivity having an effect equivalent to 25 years of ageing (P<0.02). IgA increased by 0.5 (0.1, 0.8)% per year (P<0.007), IgG being unaffected by age. Seropositivity had no effect on IgA or IgG.Conclusions: Increasing age and H. pylori seropositivity are each associated with a downward shift in circulating IgM. If clinical extrapolation is justified, H. pylori eradication may be important in combating susceptibility to infection in old age.

Urinary tract infection in old age: over-diagnosed and over-treated.

Urinary tract infection in old age: over-diagnosed and over-treated.

Post-encephalitic tremor and delayed-onset parkinsonism

Movement disorders of various types may occur in relation to viral infections of the central nervous system. They manifest themselves as obvious signs at clinical onset or during the acute phase of an encephalitis (myoclonus, tremor, or parkinsonism), or appear as later sequelae decades after the illness. We describe here a man who developed an unusual movement disorder after a probable viral encephalitis in his childhood. This consisted of a tremor (3-4Hz frequency and 100-150ms duration) of the neck, left shoulder and arm, which persisted unchanged during the ensuing years. The patient regarded this abnormal movement as annoying, but otherwise it did not impair his lifestyle. He subsequently developed the clinical picture of parkinsonism many decades after the onset of tremor, and we speculate that both tremor and parkinsonism can be considered sequelae of encephalitis, but each with a different time-course. The left-sided jerky tremor was an immediate sequela in the childhood; whereas, the rigid-akinetic parkinsonian picture represented a later sequela of the infection in old age. The injured site responsible for both the segmental tremor and the parkinsonism presumably involved the brainstem.

RETRACTED: Effect of vitamin and trace-element supplementation on immune responses and infection in elderly subjects

Ageing is associated with impaired immune responses and increased infection-related morbidity. This study assessed the effect of physiological amounts of vitamins and trace elements on immunocompetence and occurrence of infection-related illness. 96 independently living, healthy elderly individuals were randomly assigned to receive nutrient supplementation or placebo. Nutrient status and immunological variables were assessed at baseline and at 12 months, and the frequency of illness due to infection was ascertained. Subjects in the supplement group had higher numbers of certain T-cell subsets and natural killer cells, enhanced proliferation response to mitogen, increased interleukin-2 production, and higher antibody response and natural killer cell activity. These subjects were less likely than those in the placebo group to have illness due to infections (mean [SD] 23 [5] vs 48 [7] days per year, p=0·002). Supplementation with a modest physiological amount of micronutrients improves immunity and decreases the risk of infection in old age.

Urinary infection in old age

The more dependent elderly people are, the more likely they are to develop urinary infections. Professor Brocklehurst discusses prevalence and methods of treatment

Urinary tract infection in old age.

Urinary tract infection in old age.