Essential role of the CCL2-CCR2 axis in Mayaro virus-induced disease.

Mayaro virus (MAYV) is an emerging arbovirus member of the Togaviridae family and Alphavirus genus. MAYV infection causes an acute febrile illness accompanied by persistent polyarthralgia and myalgia. Understanding the mechanisms involved in arthritis caused by alphaviruses is necessary to develop specific therapies. In this work, we investigated the role of the CCL2/CCR2 axis in the pathogenesis of MAYV-induced disease. For this, wild-type (WT) C57BL/6J and CCR2-/- mice were infected with MAYV subcutaneously and evaluated for disease development. MAYV infection induced an acute inflammatory disease in WT mice. The immune response profile was characterized by an increase in the production of inflammatory mediators, such as IL-6, TNF, and CCL2. Higher levels of CCL2 at the local and systemic levels were followed by the significant recruitment of CCR2+ macrophages and a cellular response orchestrated by these cells. CCR2-/- mice showed an increase in CXCL-1 levels, followed by a replacement of the macrophage inflammatory infiltrate by neutrophils. Additionally, the absence of the CCR2 receptor protected mice from bone loss induced by MAYV. Accordingly, the silencing of CCL2 chemokine expression in vivo and the pharmacological blockade of CCR2 promoted a partial improvement in disease. Cell culture data support the mechanism underlying the bone pathology of MAYV, in which MAYV infection promotes a pro-osteoclastogenic microenvironment mediated by CCL2, IL-6, and TNF, which induces the migration and differentiation of osteoclast precursor cells. Overall, these data contribute to the understanding of the pathophysiology of MAYV infection and the identification future of specific therapeutic targets in MAYV-induced disease.IMPORTANCEThis work demonstrates the role of the CCL2/CCR2 axis in MAYV-induced disease. The infection of wild-type (WT) C57BL/6J and CCR2-/- mice was associated with high levels of CCL2, an important chemoattractant involved in the recruitment of macrophages, the main precursor of osteoclasts. In the absence of the CCR2 receptor, there is a mitigation of macrophage migration to the target organs of infection and protection of these mice against bone loss induced by MAYV infection. Much evidence has shown that host immune response factors contribute significantly to the tissue damage associated with alphavirus infections. Thus, this work highlights molecular and cellular targets involved in the pathogenesis of arthritis triggered by MAYV and identifies novel therapeutic possibilities directed to the host inflammatory response unleashed by MAYV.

Bone biology and COVID-19 infection: Is ACE2 a potential influence factor?

The outbreak of coronavirus disease 2019 (COVID-19) has posed a severe threat to global health management system since it has been detected in the human body. This pandemic was prompted by severe acute respiratory syndrome coronaviruses 2 (SARS-CoV-2) and rapidly developed into a public emergency with an alarming increase in cases and deaths. The increasing explorations to SARS-CoV-2 infection guide us to consider whether bone lesion is followed by this pathologic process. We especially focus on the underlying pathobiology that SARS-CoV-2 possibly mediated in bone remodeling and analyze the association of bone destruction with ACE2 in COVID-19 incidence, for preferable understanding the pathogenesis and providing necessary clinical management in orthopedics.

Effectiveness of Medical Nutrition Therapy to Improve Dietary Habits for Promoting Bone Health in People Living with Chronic HIV.

INTRODUCTION: Previous studies have established the risk of bone loss among people living with HIV affected by antiretroviral therapy drug side effects and inadequate nutrient intake. Until recently, there have been limits on using the medical nutrition therapy (MNT) to improve dietary habits for promoting bone health among people living with HIV. This was a randomized controlled trial study aimed to investigate the effectiveness of MNT in improving the bone health in people living with HIV by promoting dietary habits. METHODS: PLHIV at Queen Savang Vadhana Memorial Hospital were randomly grouped (by quota sampling) into the MNT group (intervention group) and the control group. One hundred and thirty PLHIV were recruited to participate in this study by convenient sampling. Sixty-five participants of the MNT group made a total of 6 appointments (for 12 weeks) to meet registered dietitians for receiving MNT to improve dietary habits for improving bone health, while 65 participants in the control group received only routine care at the hospital service center. RESULTS: In general, participants in the MNT group had significant increase in the amounts of calcium, vitamin D, potassium, and phosphorus intakes and length of exercise after the final week compared with before intervention. Also, they had significantly higher amount of nutrient intakes (calcium, vitamin D, potassium, and phosphorus) and length of exercise than the control group after finishing the final week of the experiment. CONCLUSION: In conclusion, MNT is effective for improving food habits and physical activity to promote bone health among people living with HIV.

Dysimmunity and inflammatory storm: Watch out for bone lesions in COVID-19 infection.

At the end of 2019, a new kind of pneumonia which was proven to be supported by novel coronaviruses named SARS-CoV-2 emerges and it seems to be more complicate in its clinical course and management. Related researches have demonstrated that SARS-CoV-2 serves roles in respiratory, intestinal and neuronal diseases. Given the growing cases of COVID-19, analyzing the relevance between COVID-19 and fragile patients who suffer from bone destruction is entirely indispensable. Accordingly, the recapitulatory commentary is necessary to advance our knowledge on COVID-19 and orthopedics. In this article, we particularly clarify the possible relationship between the newly COVID-19 infection and bone lesions from the standpoints of dysimmunity and inflammatory storm.

Elderly HIV-positive women: A gender-based analysis from the Multicenter Italian "GEPPO" Cohort.

BACKGROUND: HIV-positive patients are facing age-and disease-related comorbidities. Since gender differences in viro-immunological, clinical and therapeutic features have been described, aim of this analysis was to explore such differences in elderly HIV-positive females compared to males coming from the same cohort. DESIGN: Cross-sectional study. SETTING: Ten Infectious Diseases Center participating to a new multicenter Italian geriatric Cohort aiming at describing health transition over time in HIV-positive individuals. PARTICIPANTS: HIV-positive patients aged ≥65 years old. MEASUREMENTS: We recorded clinical, viro-immunological and therapeutical data. RESULTS: We included 210 women (17%) out of 1237 patients. Compared to males, elderly females were less likely to present a HIV-RNA <50 copies/mL (74.3% vs. 81.8%, OR 0.64, 95%CI 0.44-0.93); they showed higher CD4+/CD8+ ratio (p = 0.016). Combined antiretroviral therapy (cART) strategies were similar between genders (p>0.05), although women were less likely to be treated with protease Inhibitors (PIs) (p = 0.05); specifically, in triple-drug regimens females received less PIs (28% vs 38% p = 0.022) and more integrase inhibitors (30% vs. 20% p = 0.012). Bone disease was more common in females (p<0.001) while males presented more frequently cardiovascular disease (CVD) (p<0.001). In females with bone disease, PIs and boosted regimens (38% vs. 53.7% p = 0.026 and 30.4 vs 44.0% p = 0.048 respectively) were prescribed less frequently. Polypharmacy was common and similar in both genders (20% vs. 22.8%, p = >0.05). A higher use of lipid-lowering drugs (20.5% vs. 14.8%, p = 0.04) was observed in females and yet they were less likely to receive anti-thrombotic agents (18.6% vs. 26.3%, p = 0.019) even when CVD was recorded (57.1% vs. 83.1%, p = 0.018). In multivariate analysis, we found that female gender was independently associated with a higher CD4+/CD8+ ratio but not with virological suppression. CONCLUSIONS: Elderly HIV-positive women display a worse virologic response despite a better immune reconstitution compared to males. The burden of comorbidities as well as the medications received (including cART) may slightly differ according to gender. Our data suggest that more efforts and focused interventions are needed in this population.

Veterans Aging Cohort Study Index as a Marker of Bone Disease in HIV-Infected Patients.

People living with human immunodeficiency virus (HIV) infection have higher risk of low bone mineral density (BMD) and fragility fracture than general population. The aim of our retrospective study was to explore if HIV-specific Veterans Aging Cohort Study (VACS) Index and its specific components could help identify patients at risk for low BMD. A total of 195 HIV-infected patients with dual-energy X-ray absorptiometry (DXA) scan between 2007 and 2014 were included and DXA scan results were used to classify patients with osteopenia. VACS Index was calculated for all patients using laboratory values closest to the date of DXA scan. Logistic regression was used to assess the association between VACS Index score or individual components of VACS Index with the presence of low BMD after adjusting for confounding variables. A total of 109 (56%) patients were diagnosed with low BMD. VACS Index score was significantly associated with low BMD, with the odds of low BMD increasing 1.21 times for each 10 unit increase in VACS Index score [confidence interval (95% CI) 1.03-1.42; p = .02]. The two groups differed significantly on patient weights, proportion of white patients, and hepatitis C-coinfected patients. After adjusting for white race and weight, hepatitis C coinfection was significantly associated with increased risk of low BMD (odds ratio 24.4; 95% CI 7.45-80.16). VACS Index score, previously demonstrated to be a marker of frailty in HIV-infected patients, is significantly associated with risk of low BMD and could be used to develop a prediction tool to screen for low BMD in resource-limited setting where DXA scans are not easily available.

Human Immunodeficiency Virus Infection and the Endocrine System.

In the current era of effective antiretroviral therapies (ARTs), human immunodeficiency virus (HIV) infection became a chronic disorder that requires long term follow-up. Among other medical issues, these patients may develop endocrine problems, specific to HIV infection and its treatment. The purpose of this review is to give an overview of common endocrine complications associated with HIV infection, and to propose diagnostic and therapeutic strategies. HIV can affect the endocrine system at several levels. Adrenal and gonadal dysfunction, osteoporosis with increased fracture risk, dyslipidemia with increased cardiovascular risk, are some of the endocrine disorders prevalent in HIV-infected patients that may negatively influence quality of life, and increase morbidity and mortality. While ARTs have dramatically increased life expectancy in the HIV-infected population, they are not devoid of adverse effects, including endocrine dysfunction. Physicians caring for HIV-infected patients should be knowledgeable and exercise a high index of suspicion for the diagnosis of endocrine abnormalities, and in particular be aware of those that can be life threatening. Endocrine evaluation should follow the same strategies as in the general population, including prevention, early detection, and treatment.

Alfavirus tropicales artritogénicos / Tropical arthritogenic alphaviruses

Los alfavirus tropicales tienen especial tropismo por el tejido osteoarticular. Los pacientes desarrollan cuadros crónicos reumatológicos similares a la artritis reumatoide y la espondilitis anquilosante. El prototipo es el virus Chikungunya, aunque otros virus menos conocidos en nuestro medio como Sindbis, Ross River, Mayaro, O’nyong nyong y Barmah Forest tienen un potencial para propagarse a través de vectores y causar cuadros reumatológicos crónicos. Los movimientos poblacionales internacionales han aumentado el número de pacientes diagnosticados por estos virus tropicales en zonas no endémicas. Dado que pueden dejar secuelas y afectar la calidad de vida, es importante conocerlos. Los cambios en los ecosistemas han favorecido la expansión de mosquitos competentes, haciendo realidad el temor de transmisión local en el sur de Europa. El objetivo de esta revisión es dar una aproximación clínica de los distintos alfavirus tropicales artritogénicos, especialmente de aquellos en los que la patología reumática crónica es más frecuente (AU)

Tropical alphaviruses have special tropism for bone and joint tissue. Patients can develop chronic rheumatic disorders similar to rheumatoid arthritis and ankylosing spondylitis. The prototype is Chikungunya virus, although other lesser known viruses in our environment such as Sindbis, Ross River, Mayaro, O’nyong nyong and Barmah Forest viruses have the potential to be sped through vectors and cause chronic rheumatic disease. International population movements have increased the numbers of patients diagnosed with these tropical viruses in areas in which they are not endemic. Since they can leave persistent symptoms and affect the quality of life of the patients, it is important that we be aware of them. Changes in ecosystems have favored the expansion of competent mosquitoes, making fears of local transmission in southern Europe a reality. The objective of this review is to provide a clinical approach to the different arthritogenic tropical alphaviruses, especially those in which chronic rheumatic disease is more frequent (AU)

Bone Disease in HIV: Recommendations for Screening and Management in the Older Patient.

Availability of potent antiretroviral therapy (ART) has resulted in markedly improved survival for people with human immunodeficiency virus (HIV) infection, as well as an aging HIV population. Increasing morbidity from age-related conditions has resulted in the need to understand the complex roles HIV and its treatment play in the pathogenesis of these conditions. Bone disease and fragility fractures are conditions that occur more frequently in HIV. It is therefore recommended that risk assessment for fragility fracture using the Fracture Risk Assessment Tool (FRAX(®)) algorithm, and low bone mass by dual energy X-ray absorptiometry (DXA) scan, be performed in all patients with HIV infection over the age of 50 years and in those with a history of fragility fracture, and should be repeated every 2-3 years. Because many HIV experts believe that HIV infection and its treatment is a secondary cause of osteoporosis, it should be included as such in the FRAX(®) assessment tool. Management of osteoporosis in HIV infection should follow the same guidelines as that in the general population. Attention to lifestyle factors, including vitamin D replacement, should be emphasized. Whether cessation of tenofovir- or protease inhibitor-based ART regimens should be considered prior to bisphosphonate treatment is currently unknown and should only occur in patients with active alternative ART regimens. The use of bisphosphonates has been shown to be safe and effective in HIV patients, and while there is limited data on second-line osteoporosis regimens, there is no reason to suggest they would not be effective in people with HIV.

Soft plastron, soft carapace with skeletal abnormality in juvenile tortoises. Histopathology and isolation of a novel picornavirus from Testudo graeca and Geochelone elegans.

OBJECTIVE: A disease is described in juvenile tortoises (Testudo graeca and Geochelone elegans) consisting mainly of a soft carapace, soft plastron and deformed skeleton. The aim of this study was to determine histopathological lesions and the biological properties of the isolated viruses. MATERIALS AND METHODS: Clinical signs and gross pathology were determined on diseased and healthy appearing tortoises. Paraffin sections were stained with HE, PAS and Prussian Blue and histologically examined. Terrapene heart (TH-1) cell cultures served for virus isolations from 64 tissues and 104 swabs. One isolate (isolate 1243/37 tongue) was used in neutralization tests on 19 sera. RESULTS: Retarded growth and increasingly soft plastron and carapace were the prominent signs in diseased tortoises. Pathological lesions consisted of dilated urinary sac, enlarged kidneys and livers. Histopathologically, hepatic hemosiderosis, hypoplastic anaemia, congestive glomerulonephrosis and osteodystrophy were seen. A novel vi- rus ("virus X") was isolated from 64 organs and 79 of 104 swabs. The isolated viruses were identified as a novel chelonid picornavirus based on cytopathic effect, resistance to chloroform and stability at low pH. Co-cultivation with 5-iodo-2'-deoxyuridine and actinomycin D did not reduce virus titres. Electron microscopically, round, non-enveloped particles (25-30 nm) were detected. Neutralizing antibodies to the isolate 1243/37tongue were present in 17 of 19 sera from seven species of tortoises. CONCLUSION AND CLINICAL RELEVANCE: Nephropathy, osteodystrophy and virus isolations suggest a viral aetiology. Metabolic bone disease is the major differential diagnosis. Further investigations in vivo are needed to evaluate the likely effects of the picornavirus on tortoises.

Focal bone lesions in HIV-positive patient treated with tenofovir.

BACKGROUND: Tenofovir is a widely used antiviral drug for the treatment of HIV and HBV infection. Although its side effects on renal function and bone metabolism are well known, there are no reports on focal bone lesions caused by this drug. Our case suggests this new, unusual but important scenario. CASE PRESENTATION: We report on a 46-year-old HIV-positive man treated with an antiretroviral regimen containing tenofovir who suddenly developed localized inflammatory bone lesions. The examinations performed ruled out all the disorders commonly associated with this clinical pattern, and the patient's conditions improved only after the suspension of tenofovir. CONCLUSIONS: The case study suggests a rare but severe adverse event, which should be taken into account when physicians treat HIV-positive patients with focal inflammatory bone lesions.

HIV infection and bone disease: implications for an aging population.

Now more than ever, the management of age-related problems, from cardiovascular morbidity to bone pathology, is increasingly relevant for HIV physicians. Low bone mineral density (BMD) and fractures are more common in HIV-infected patients. Although a multifactorial aetiology underlies this condition, increasing evidence suggests a role for antiretroviral therapy in low BMD, especially upon initiation. This review will detail the epidemiology, pathogenesis, diagnosis and management of osteoporosis and low BMD in HIV-infected patients, with particular emphasis on aging.

Bone turnover markers in HIV disease.

Biomarkers are being increasingly used in basic and clinical research of HIV disease as well as clinical management of infected individuals. Bone metabolism can be assessed by measurement of bone turnover markers, molecules released during bone formation and removal of old bone (resorption). In HIV-infected adults, there is a higher prevalence of low bone mineral density and fractures compared to the general population. This review discusses the findings regarding bone turnover markers in HIV-uninfected and -infected populations and their potential role in assessing fracture risk and predicting bone loss. Studies in postmenopausal women and elderly men show that increased bone turnover markers levels are associated with bone loss, and high levels of resorption markers may predict fractures independently of bone mineral density. Several HIV-related factors, including HIV infection and inflammation, have been found to affect the balance between bone formation and resorption. Some clinical studies found increased levels of bone turnover markers in HIV-infected adults compared to uninfected controls. Furthermore, bone turnover marker levels increased following initiation or switch to different antiretroviral agents in recent randomized trials. The clinical value of bone turnover markers is currently limited due to different sources of variability and limited data from studies in HIV-infected populations. Further research is needed to explore the potential value of bone turnover markers as additional measurements to bone mineral density in fracture risk assessment and monitoring treatment-induced bone effects in HIV-infected patients.

HIV infection, inflammation, immunosenescence, and aging.

Although antiretroviral therapy for HIV infection prevents AIDS-related complications and prolongs life, it does not fully restore health. Long-term treated patients remain at higher than expected risk for a number of complications typically associated with aging, including cardiovascular disease, cancer, osteoporosis, and other end-organ diseases. The potential effect of HIV on health is perhaps most clearly exhibited by a number of immunologic abnormalities that persist despite effective suppression of HIV replication. These changes are consistent with some of the changes to the adaptive immune system that are seen in the very old ("immunosenescence") and that are likely related in part to persistent inflammation. HIV-associated inflammation and immunosenescence have been implicated as causally related to the premature onset of other end-organ diseases. Novel therapeutic strategies aimed at preventing or reversing these immunologic defects may be necessary if HIV-infected patients are to achieve normal life span.

[Rosai-Dorfman disease: clinicopathologic, immunohistochemical and etiologic study of 16 cases].

OBJECTIVES: To study the clinicopathologic features of Rosai-Dorfman disease (RDD), expression of various antigens, human herpes virus type 8 (HHV8), human papillomavirus (HPV)-DNA and Epstein-Barr virus (EBV)-mRNA, and compare the findings with those in the literature. METHODS: The clinicopathologic findings of 16 Rosai-Dorfman disease cases were retrospectively reviewed. Immunohistochemical study for S-100 protein, CD68 (PG-M1), CD163, CD21, CD1a, CD20, CD45RO, CD4, CD8, M-CSF and HHV8 was carried out in 9 of the 16 cases. In-situ hybridization for EBV-mRNA and HPV-DNA was also performed. RESULTS: The male-to-female ratio of the patients was 4.33:1. Amongst the 16 cases studied, 62.5% (10/16) presented nodal RDD, with cervical lymph node predominantly involved. Half of these cases had affected lymph nodes in more than one anatomic site. Extranodal RDD represented 37.5% (6/16) of the cases. The relapse rate of extranodal RDD was higher than that of nodal RDD. Histologically, nodal RDD was characterized by dilated sinuses filled with large polygonal histiocytes which contained lymphocytes and plasma cells. For extranodal lesions, various degrees of stromal fibrosis were seen in association with mixed inflammatory cells (especially plasma cells). The large polygonal histiocytes varied in number and were distributed in clusters or patches. Immunohistochemical study showed that the abnormal histiocytes were strongly positive for S-100 protein. They also expressed CD68, CD163 and M-CSF, but were negative for CD1a, CD21 and HHV8. The lymphocytes in cytoplasm of these histiocytes were positive for both T and B cell markers (with T cell predominance, including a mixture of CD4- and CD8-positive cells). HPV-DNA and EBV-mRNA were not detected by in-situ hybridization. To date, 62 cases of RDD have been reported in mainland China, including 34 cases of nodal RDD and 18 cases of extranodal RDD. The remaining 10 cases involved both lymph nodes and extranodal sites. Compared with overseas reports, RDD occurring in China tended to affect older patients and with slight male predilection. CONCLUSIONS: Rosai-Dorfman disease is relatively rare in China. Pathologic diagnosis of extranodal RDD may be difficult. The demographic data of RDD in China, including age and sex of patients, are different from those in the literature.

Is HIV sequestered in bone? Possible implications of virological and immunological findings in some HIV-infected patients with bone disease.

To determine the prevalence of CD4 lymphocyte levels less than 350 cells/mm3 accompanying viral loads (VL) less than 500 copies/ml (discordant CD4 lymphocyte levels/VL) in HIV-infected men with bone pathologies, we conducted a review of the records of 3512 men. We found discordant CD4 lymphocyte levels/VL in 26 (36.1%) out of 72 with bone pathologies, and in 704 (20.5%) out of 3440 without bone pathologies (P < 0.01), and concluded that HIV sequestered in bone was a possible explanation.

Acquired osteosclerosis associated with intravenous drug use and hepatitis C infection.

Hepatitis C has recently been recognized as a secondary cause of osteosclerosis; a further example, the first outside of North America, is described. A 37-year-old man with a history of intravenous drug use and known to be hepatitis C antibody positive presented with bone pain. Radiographs and magnetic resonance imaging demonstrated an increase in cortical and trabecular bone that on biopsy was of a normal lamellar pattern but markedly sclerotic. Biochemical markers of bone formation (serum osteocalcin) and resorption (urinary hydroxyproline excretion rate) were both markedly elevated. Pain lessened following administration of pamidronate. Biochemical markers of bone turnover fell towards their reference ranges 12 months after initiating pamidronate therapy but without significant change in bone mineral density. Osteosclerosis is a rare complication of hepatitis C infection, the symptoms of which are controllable with diphosphonate therapy.

Paget's disease of bone and unvaccinated dogs.

The etiology of Paget's disease is unknown, but several observations suggest a viral cause. Since canine distemper virus is among those proposed to be a causal agent, we investigated the hypothesis that dog ownership may increase the risk of Paget's disease of bone by means of a case control study. One hundred and fifty patients with Paget's disease and 185 controls were interviewed using a structured questionnaire administered by the same interviewer. Participants were asked about their socioeconomic background and their exposure to pets. The risk of Paget's disease was not significantly increased in individuals. However, ownership of a mongrel dog was associated with a significant increase in risk (OR = 1.6; 95% CI = 1.0-2.4) and the risk increased still further with the ownership of an unvaccinated dog (OR = 2.8; 95% CI = 1.8-4.5). Additionally, ownership of cats and birds excluding dog owners, increased the risk of Paget's disease (OR = 2.5; 95% CI = 1.0-5.0; OR = 2.3; 95% CI = 1.0-5.3, respectively). These data suggest that previous exposure to cats, birds, and dogs unvaccinated for canine distemper may increase the risk of an individual developing Paget's disease of bone.