Diagnosis, Treatment and Long-Term Management of Vitamin B12 Deficiency in Adults: A Delphi Expert Consensus

Background/Objectives: Vitamin B12 deficiency can cause variable symptoms, which may be irreversible if not diagnosed and treated in a timely manner. We aimed to develop a widely accepted expert consensus to guide the practice of diagnosing and treating B12 deficiency. Methods: We conducted a scoping review of the literature published in PubMed since January 2003. Data were used to design a two-round Delphi survey to study the level of consensus among 42 experts. Results: The panelists agreed on the need for educational and organizational changes in the current medical practices for diagnosing and treating B12 deficiency. Recognition of clinical symptoms should receive the highest priority in establishing the diagnosis. There is agreement that the serum B12 concentration is useful as a screening marker and methylmalonic acid or homocysteine can support the diagnosis. Patient lifestyle, disease history, and medications can provide clues to the cause of B12 deficiency. Regardless of the cause of the deficiency, initial treatment with parenteral B12 was regarded as the first choice for patients with acute and severe manifestations of B12 deficiency. The use of high-dose oral B12 at different frequencies may be considered for long-term treatment. Prophylactic B12 supplementation should be considered for specific high-risk groups. Conclusions: There is a consensus that clinical symptoms need to receive more attention in establishing the diagnosis of B12 deficiency. B12 laboratory markers can support the diagnosis. The severity of clinical symptoms, the causes of B12 deficiency, and the treatment goals govern decisions regarding the route and dose of B12 therapy.

Association of Long-term Exposure to Air Pollution and Dementia Risk: The Role of Homocysteine, Methionine, and Cardiovascular Burden

BACKGROUND AND OBJECTIVES

Growing evidence links air pollution with dementia risk, but the biological mechanisms are largely unknown. We investigated the role played by homocysteine (tHcy) and methionine in this association and explored whether this could be explained by cardiovascular diseases (CVDs).

METHODS

Data were extracted from the ongoing Swedish National study on Aging and Care in Kungsholmen (SNAC-K), a longitudinal population-based study. At baseline, 2,512 dementia-free participants were examined up to 2013 (mean follow-up: 5.18 ± 2.96 years). Two air pollutants (particulate matter ≤2.5 μm [PM2.5] and nitrogen oxides [NOx]) were assessed yearly from 1990 until 2013 using dispersion models at residential addresses. The hazard ratio of dementia over air pollution levels was estimated using Cox models adjusted for age, sex, education, smoking, socioeconomic status, physical activity, retirement age, creatinine, year of assessment, and the use of supplements. The total effect of air pollutants on dementia was decomposed into 4 pathways involving tHcy/methionine: (1) direct effect; (2) indirect effect (mediation); (3) effect due to interaction; and (4) effect due to both mediation and interaction. To test whether the association was independent from CVDs (ischemic heart disease, atrial fibrillation, heart failure, and stroke), we repeated the analyses excluding those individuals who developed CVDs.

RESULTS

The mean age of the study participants was 73.4 years (SD: 10.4), and 62.1% were female individuals. During an average period of 5 years (mean: 5.18; SD: 2.96 years), 376 cases with incident dementia were identified. There was a 70% increased hazard of dementia per unit increase of PM2.5 during the 5 years before baseline (hazard ratio [HR]: 1.71; 95% CI 1.33-2.09). Overall, 50% (51.6%; 95% CI 9.0-94.1) of the total effect of PM2.5 on dementia was due to mediation of tHcy (6.6%; 95% CI 1.6-11.6) and/or interaction (47.8%; 95% CI 4.9-91.7) with tHcy and 48.4% (p = 0.03) to the direct effect of PM2.5 on dementia. High levels of methionine reduced the dementia hazard linked to PM2.5 by 31% (HR: 0.69; 95% CI 0.56-0.85) with 24.8% attributable to the interaction with methionine and 25.9% (p = 0.001) to the direct effect of PM2.5. No mediation effect was found through methionine. Attenuated results were obtained for NOx. Findings for tHcy were attenuated after excluding those who developed CVDs, while remained similar for methionine.

DISCUSSION

High levels of homocysteine enhanced the dementia risk attributed to air pollution, while high methionine concentrations reduced this risk. The impact of homocysteine on cardiovascular conditions partly explains this association. Alternative pathways other than cardiovascular mechanisms may be at play between methionine and dementia.

Markers of vitamin B12 status in relation to cerebrospinal fluid biomarkers of Alzheimer's disease and cognitive performance

BACKGROUND

The association between markers of vitamin B12 status and cerebrospinal fluid (CSF) biomarkers of Alzheimer's disease (AD) which precede cognitive impairment has been investigated by only a few small studies and results have been inconsistent.

AIM

To investigate the associations of vitamin B12 related markers with CSF biomarkers of AD and cognitive performance.

METHODS

Data included 462 patients aged 40-94 years referred to the Memory Clinic of the Ulm University Hospital, Ulm, Germany. Vitamin B12, holotranscobalamin (HoloTC), homocysteine (tHcy), and methylmalonic acid (MMA) have been measured. CSF values of amyloid β₄₂ (Aβ₄₂ ) and total-tau have been assessed in 227 participants. CERAD battery was administered to examine the cognitive status, and different domains were derived. Regression models were used to investigate the associations.

RESULTS

In the multiadjusted model, higher levels of MMA were associated with raised CSF total-tau values: the odds ratios (OR) (95% confidence intervals (CI)) were 3.25 (1.35-7.76) for the highest quartile of MMA compared to the lowest. Furthermore, moderately increased MMA were related to lower Aβ₄₂ levels: the OR (95% CI) were 3.06 (1.22-7.67) for the third quartile of MMA compared to the lowest. All B12 indicators except B12 itself were related to several cognitive domains such as episodic memory and executive functioning.

CONCLUSIONS

Markers of vitamin B12 may be independent predictors of CSF biomarkers of Alzheimer's disease and cognitive functioning, with methyl malonic acid showing the most consistent effects. Randomized controlled trials are needed to determine the importance of vitamin B12 supplementation on slowing structural brain changes and cognitive decline. This article is protected by copyright. All rights reserved.

Glutathione Serum Levels and Rate of Multimorbidity Development in Older Adults

We aimed to investigate the association between baseline levels of total serum glutathione (tGSH) and rate of chronic disease accumulation over time. The study population (n = 2,596) was derived from a population-based longitudinal study on ≥60-year-olds living in Stockholm. Participants were clinically assessed at baseline, 3- and 6-year follow-ups. Multimorbidity was measured as the number of chronic conditions from a previously built list of 60 diseases. Linear mixed models were applied to analyze the association between baseline tGSH levels and the rate of multimorbidity development over 6 years. We found that at baseline, participants with ≥4 diseases had lower tGSH levels than participants with no chronic conditions (3.3 vs 3.6 µmol/L; p < .001). At follow-up, baseline levels of tGSH were inversely associated with the rate of multimorbidity development (β * time: -0.044, p < .001) after adjusting for age, sex, education, levels of serum creatinine, C-reactive protein, albumin, body mass index, smoking, and time of dropout or death. In conclusion, serum levels of tGSH are inversely associated with multimorbidity development; the association exists above and beyond the link between tGSH and specific chronic conditions. Our findings support the hypothesis that tGSH is a biomarker of multisystem dysregulation that eventually leads to multimorbidity.

Association of Homocysteine, Methionine, and MTHFR 677C>T Polymorphism With Rate of Cardiovascular Multimorbidity Development in Older Adults in Sweden

IMPORTANCE

Strong evidence links high total serum homocysteine (tHcy) and low methionine (Met) levels with higher risk of ischemic disease, but other cardiovascular (CV) diseases may also be associated with their pleiotropic effects.

OBJECTIVES

To investigate the association of serum concentrations of tHcy and Met with the rate of CV multimorbidity development in older adults and to explore the role of methylenetetrahydrofolate reductase (MTHFR) 677C>T polymorphism in this association.

DESIGN, SETTING, AND PARTICIPANTS

The Swedish National Study on Aging and Care in Kungsholmen is a cohort study of randomly selected individuals aged 60 years or older. The present study included data on 1969 individuals with complete information and without CV diseases at baseline, collected from the baseline examination (2001-2004) to the fourth follow-up (2013-2016). Data analysis was conducted from January to May 2019.

EXPOSURES

Concentrations of tHcy and Met were measured from nonfasting venous blood samples. The Met:tHcy ratio was considered a possible indicator of methylation activity. MTHFR status was dichotomized as any T carriers vs noncarriers.

MAIN OUTCOME AND MEASURES

The number of CV diseases at each wave was ascertained based on medical interviews and records, laboratory test results, and drug data. Linear mixed models were used to study the association of baseline tHcy and Met levels and the rate of CV multimorbidity development, adjusting for sociodemographic characteristics, CV risk factors, chronic disease burden, and drug use.

RESULTS

Of 1969 participants, most were women (1261 [64.0%]), with a mean (SD) age of 70.9 (9.8) years; 1703 participants (86.6%) had at least a high school level of education. Baseline measurements of serum tHcy, Met, and the Met:tHcy ratio were associated with the rate of CV disease accumulation (tHcy: β = 0.023 per year; 95% CI, 0.015 to 0.030; P < .001; Met: β = -0.007 per year; 95% CI, -0.013 to -0.001; P = .02; Met:tHcy ratio: β = -0.017 per year; 95% CI, -0.023 to -0.011; P < .001). The association between low Met concentrations and the rate of CV multimorbidity development was restricted to the group with CT/TT alleles of MTHFR (β = 0.023 per year; 95% CI, 0.006 to 0.041; P = .009). Results remained largely significant when individual CV diseases were removed from the total count 1 at a time (eg, ischemic heart disease, tHcy: β = 0.023 per year; 95% CI, 0.013 to 0.027; P < .001; Met: β = -0.006 per year; 95% CI, -0.011 to -0.0003; P = .04; Met:tHcy ratio: β = -0.015 per year; 95% CI, -0.020 to -0.009; P < .001).

CONCLUSIONS AND RELEVANCE

In this study, high tHcy and low Met levels were associated with faster CV multimorbidity development in older age. The interactive association of Met concentrations and MTHFR polymorphism, together with the association found for the Met:tHcy ratio, point toward the relevance of impaired methylation in the pathogenesis of CV aging.

Association of Methionine to Homocysteine Status With Brain Magnetic Resonance Imaging Measures and Risk of Dementia

IMPORTANCE

Impairment of methylation status (ie, methionine to homocysteine ratio) may be a modifiable risk factor for structural brain changes and incident dementia.

OBJECTIVE

To investigate the association of serum markers of methylation status and sulfur amino acids with risk of incident dementia, Alzheimer disease (AD), and the rate of total brain tissue volume loss during 6 years.

DESIGN, SETTING, AND PARTICIPANTS

This population-based longitudinal study was performed from March 21, 2001, to October 10, 2010, in a sample of 2570 individuals aged 60 to 102 years from the Swedish Study on Aging and Care in Kungsholmen who were dementia free at baseline and underwent comprehensive examinations and structural brain magnetic resonance imaging (MRI) on 2 to 3 occasions during 6 years. Data analysis was performed from March 1, 2018, to October 1, 2018.

MAIN OUTCOMES AND MEASURES

Incident dementia, AD, and the rate of total brain volume loss.

RESULTS

This study included 2570 individuals (mean [SD] age, 73.1 [10.4] years; 1331 [56.5%] female). The methionine to homocysteine ratio was higher in individuals who consumed vitamin supplements (median, 1.9; interquartile range [IQR], 1.5-2.6) compared with those who did not (median, 1.8; IQR, 1.3-2.3; P < .001) and increased per each quartile increase of vitamin B12 or folate. In the multiadjusted model, an elevated baseline serum total homocysteine level was associated with an increased risk of dementia and AD during 6 years: for the highest homocysteine quartile compared with the lowest, the hazard ratios (HRs) were 1.60 (95% CI, 1.01-2.55) for dementia and 2.33 (95% CI, 1.26-4.30) for AD. In contrast, elevated concentrations of methionine were associated with a decreased risk of dementia (HR, 0.54; 95% CI, 0.36-0.81) for the highest quartile compared with the lowest. Higher values of the methionine to homocysteine ratio were significantly associated with lower risk of dementia and AD: for the fourth methionine-homocysteine quartile compared with the first quartile, the HR was 0.44 (95% CI, 0.27-0.71) for incident dementia and 0.43 (95% CI, 0.23-0.80) for AD. In the multiadjusted linear mixed models, a higher methionine to homocysteine ratio was associated with a decreased rate of total brain tissue volume loss during the study period (β [SE] per 1-SD increase, 0.038 [0.014]; P = .007).

CONCLUSIONS AND RELEVANCE

The methionine to homocysteine status was associated with dementia development and structural brain changes during the 6-year study period, suggesting that a higher methionine to homocysteine ratio may be important in reducing the rate of brain atrophy and decreasing the risk of dementia in older adults.

403. Clinical Features and Treatment Outcome of Enterobacter Prostethic Joint Infections

Background

Methods

Results

Conclusion

Disclosures

381. Clinical Outcome of Polymicrobial Prosthetic Joint Infection Managed with Debridement, Antibiotics, and Implant Retention (DAIR)

Background

Polymicrobial (PM) prosthetic joint infections (PJIs) account for 4% to 37% of all PJIs. There is limited literature on surgical debridement, antibiotics and implant retention (DAIR) in PMPJIs. We aimed to assess clinical outcomes of PMPJIs managed with DAIR.

Methods

A retrospective cohort was studied at three Ascension hospitals in Detroit from January 2012 to December 2018. Cases were identified using the International Classification of Diseases, 9th and 10^th Revision code specific for PJIs. Patient’s electronic medical records were reviewed.

Results

Twenty-six PMPJIs managed with DAIR were identified. Mean age of the infected patients was 66 years. 18 (69%) patients were female and 19 (73%) were caucasians. Infected sites were hip in 15 (58%), knee in 10 (38%) and ankle in 1 (4%) patient. 22 (85%) patients had osteoarthritis, 3 (12%) had diabetes, 3 (12%) were on steroids and 1 (4%) had rheumatoid arthritis. Symptom onset of less than a week was noted in 14 (58%) and 3 or more weeks in 8 (31%) patients. Pain, swelling and drainage were present in 21 (81%), 13 (50%) and 18 (69%) cases. Fever on admission was noted in 7 (27%) patients. 11 (42%) patients were re-admitted in the following 12 months after DAIR. 2 (19%) patients developed superficial surgical site infection (SSI) while 9 (81%) had deep SSI. Implant removal was needed in 6 (55%) patients. 5 (2 superficial and 3 deep) patients required further debridement and antibiotics. 5 (19%) had good outcome with 3–6 months of antibiotics. 3 (12%) patients required long-term chronic suppressive therapy. One patient died from a cardiac event during follow-up.

Conclusion

In our study, PMPJIs managed with DAIR had high readmission rates and deep surgical site infections. DAIR failure, noted in 23% of our cases, required implant removal within 12 months of follow-up.

Disclosures

All authors: No reported disclosures.

171. Rising Rates of Gram-Negative Bacilli Blood Stream (GNB-BSI) Infection in Adults

Background

Monitoring bloodstream infections provides updates of the microbiology and antibiotic susceptibility trends. We elected to examine GNB-BSI.

Methods

We retrospectively studied adults (≥18 years old) inpatients with gram-negative bacilli (GNB) bloodstream infection (BSI; January 1, 2010–December 31, 2017), determined the demographics, onset place, microbiology and source. The results were stratified to study year and evaluated by the extended Mantel–Haenszel chi square for linear trends.

Results

GNB were encountered in 4520/14314 (31.6%) positive blood culture (BC) accounting for 2811 BSI episodes (2291 patients) with a steadily increasing rate (table). The 3 most common organisms were Escherichia coli (EC; 44.4%), Klebsiella pneumoniae (KP; 19.2%) and Pseudomonas aeruginosa (PA; 9.6%). GNB-BSI rate increase was mainly in EC-BSI (P = 0.01). The rate of other GNB-BSI did not change. Source distribution of EC-BSI did not change and antibiotic resistance did not change.

Conclusion

GNB-BSI is rising, primarily due to EC, without changes in source distribution or antibiotic susceptibility. Prospective studies to look at EC lineage and virulence factors are needed to determine the reason for EC-BSI rise.

Disclosures

All authors: No reported disclosures.

180. Klebsiella pneumoniae and K. oxytoca Bacteremia: Differences in Host, Source, and Antibiotic Susceptibility

Background

Klebsiella species (KS) bloodstream infection (BSI) is often caused by K. pneumoniae (KP). K. oxytoca (KO) is emerging and implicated in antibiotic-associated right-sided colitis. We compared the clinical and microbiological characteristics of KP and KO.

Methods

We reviewed blood culture (BC) results (January 1, 2010–December 31, 2017), selected patients with KS in ≥1 BC, reviewed their medical records, abstracted patient demographics, source of bacteremia, antibiotics susceptibility, and outcome. Each patient was counted once. We compared KP and KO cases. All differences were assessed by the chi-square test and regression analysis, using SPSS.

Results

We encountered KS in 975/14,256 (6.8%) positive BC, representing 611 BSI including 537 KP-BSI (484 patients) and 55 KO-BSI cases (54 patients); each patient was counted once. Mean age and prevalence of diabetes and most comorbidities were similar but KO was less frequent in African Americans (40.7% vs. KP [61.3%]; P = 0.005) and in patients with neurological debility (Stroke, paraplegia, multiple sclerosis; 11.1% vs. KP [24.8%]; P = 0.03). KO BSI was more frequent in IVC BSI and was absent in pneumonia-associated BSI (table). Antibiotic resistance was rare among KO isolates except for cefazolin-intermediate susceptibility (42.6% vs. 1.7%; P < 0.001). CREs were limited to KP. Logistic regression analysis confirmed KO link to IVC (OR = 3.57; 95% CI: 1.89, 6.76; P < 0.001) and Caucasian race (OR = 2.46; CI: 1.37, 4.42; P = 0.003). Mortality rate was comparable (28.1% [KP] vs. 35.2% [KO]; P = 0.3).

Source and antibiotic susceptibility (%) in K. pneumoniae and K. oxytoca bacteremia

Conclusion

KO and KP BSI differ in the type of host and source, suggesting different colonization dynamics. KO remains antibiotic-susceptible but might be cefazolin less susceptible. Prospective studies are needed to confirm differential cephalosporin susceptibility and delineate host–pathogen interactions.

Disclosures

All authors: No reported disclosures.

2285. Emergence of perioperative antibiotic non-susceptible pathogens causing prosthetic joint infections in monomicrobial Gram-negative and polymicrobial infections

Background

Current recommendations by Infectious diseases society of America (IDSA) endorse cefazolin for perioperative use. What is less known currently is the emergence of resistance in Gram-positive (GP) and Gram-negative (GN) prosthetic joint infections (PJIs) in the setting of perioperative use of antibiotics.

Methods

A retrospective multi-centric cohort was studied at three hospitals from January 2012 to December 2018. Patients with PJIs were identified using ICD codes. We reviewed electronic medical records and identified PJIs which followed primary arthroplasties. We included cases where perioperative antibiotics records were available.

Results

66 infected PJIs with available preoperative records were included. 40 (61%) patients were females, and 42 (64%) were caucasians. Indications for undergoing arthroplasty were degenerative joint disease (DJD) in 52 (78%), trauma in 13 (20%) and avascular necrosis in 1 (1.5%). Sites for arthroplasty were knee in 33 (50%), hip 28 (42.5%), shoulder 4 (6%), and ankle in 1(1.5%). 43 (65%) had GP monomicrobial, 6 (9%) had GN monomicrobial and 17 (26%) had polymicrobial infections. 40 (60.5%) patients received cefazolin, 25 (38%) received vancomycin and 1 (1.5%) received ceftriaxone as perioperative prophylaxis. 7 (11%) PJIs among monomicrobial infections and 6 (35%) among polymicrobial infections had non-susceptible (NS) organisms (Figure 1 and 2). 8 (47%) polymicrobial PJIs had a mixed susceptibility profile with drug susceptible and resistant organisms.

Conclusion

In general, when monomicrobial GP pathogens are causative for PJI, current use of cefazolin as perioperative drug of choice is sound and we agree with the current perioperative recommendations. It should be recognized that in situations where the PJI is due to GN or is polymicrobial, resistance to perioperative antibiotics may be present at a greater rate. From this study we conclude that in cases where the pathogen is known to be GN or polymicrobial from a diagnostic aspiration, then a broader antibiotic selection may be of benefit perioperatively.

Disclosures

All authors: No reported disclosures.

Fusobacterium nucleatum: A cause of subacute liver abscesses with extensive fibrosis crossing the diaphragm, mimicking actinomycosis

Introduction

Fusobacterium nucleatum is a Gram-negative, obligate anaerobic bacterium which predominantly resides within the oral cavity and causes acute abscesses and venous thrombosis, primarily in the head and neck region, but could have unique clinical presentations in different anatomical regions of the body.

Case report

We present a case of subacute liver abscesses extending to the lung. The histopathological examination showed extensive necrosis and fibrosis. The chronic course, extensive fibrosis and extension across the anatomic barriers were suggestive of actinomycosis. two sets of blood cultures grew Fusobacterium nucleatum, only 16s rRNA analysis of the liver tissue and pleural fluid revealed F. nucleatum DNA without other organisms. The clinical and pathological features of our case illustrate that F. nucleatum may mimic actinomycosis.

Conclusions

This case illustrates that F. nucleatum should be considered in patients with subacute infections with extensive fibrosis that crosses anatomic barriers, mimicking actinomycosis.

Serum Insulin and Cognitive Performance in Older Adults: A Longitudinal Study

PURPOSE

The aim of this study was to examine the association of serum glucose, insulin, and insulin resistance with cognitive functioning 7 years later in a longitudinal population-based study of Finnish older adults.

METHODS

Serum glucose and insulin were measured at baseline in 269 dementia-free individuals aged 65-79 years, from the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study. Insulin resistance was estimated with the homeostasis model assessment (HOMA-IR). Participants were reexamined 7 years later, and global cognition, episodic memory, executive functioning, verbal expression, and psychomotor speed were assessed, both at baseline and at follow-up. Multiple linear regression was used to investigate the associations with cognitive performance at follow-up, after adjusting for several potential confounders, including common vascular risk factors.

RESULTS

In the multivariable-adjusted linear regression models, no associations of insulin resistance with cognitive functioning were observed. After excluding 19 incident dementia cases, higher baseline HOMA-IR values were related to worse performance in global cognition (β [standard error (SE)] -.050 [0.02]; P = .043) and psychomotor speed (β [SE] -.064 [.03]; P = [.043]) 7 years later. Raised serum insulin levels were associated with lower scores on global cognition (β [SE] -.054 [.03]; P = .045) and tended to relate to poorer performance in psychomotor speed (β [SE] -.061 [.03]; P = .070).

CONCLUSIONS

Serum insulin and insulin resistance may be independent predictors of cognitive performance 7 years later in elderly individuals without dementia. Randomized controlled trials are needed to determine this issue.

Homocysteine and Dementia: An International Consensus Statement

Identification of modifiable risk factors provides a crucial approach to the prevention of dementia. Nutritional or nutrient-dependent risk factors are especially important because dietary modifications or use of dietary supplements may lower the risk factor level. One such risk factor is a raised concentration of the biomarker plasma total homocysteine, which reflects the functional status of three B vitamins (folate, vitamins B12, B6). A group of experts reviewed literature evidence from the last 20 years. We here present a Consensus Statement, based on the Bradford Hill criteria, and conclude that elevated plasma total homocysteine is a modifiable risk factor for development of cognitive decline, dementia, and Alzheimer’s disease in older persons. In a variety of clinical studies, the relative risk of dementia in elderly people for moderately raised homocysteine (within the normal range) ranges from 1.15 to 2.5, and the Population Attributable risk ranges from 4.3 to 31%. Intervention trials in elderly with cognitive impairment show that homocysteine-lowering treatment with B vitamins markedly slows the rate of whole and regional brain atrophy and also slows cognitive decline. The findings are consistent with moderately raised plasma total homocysteine (>11 μmol/L), which is common in the elderly, being one of the causes of age-related cognitive decline and dementia. Thus, the public health significance of raised tHcy in the elderly should not be underestimated, since it is easy, inexpensive, and safe to treat with B vitamins. Further trials are needed to see whether B vitamin treatment will slow, or prevent, conversion to dementia in people at risk of cognitive decline or dementia.

1005. HIV-Associated Bloodstream Infection (BSI): Trends Over 7 Years

Background

Patients with HIV are known to be at risk for bacteremia. Whether the type of organisms changed over time is uncertain. We present a review of bacteremia in HIV-patients during 2010–2016.

Methods

We reviewed blood culture (BC) results (January 1, 2010–December 31, 2016), selected patients with BSI, defined their HIV status, the place of onset (community onset [CO]: 0–3 days after admission; hospital onset [HO]: ≥4 days), patient demographics, the source and organism distribution and compared patients with and without HIV.

Results

We encountered 5,179 BSI episodes, 93 were among 73 HIV-patients (table). HIV patients were younger, and more likely to be African Americans. Majority of cases were community onset (79.1% and 74.5% in cases with/without HIV, respectively). The three most common organisms in HIV patients were Staphylococcus aureus (SA), Escherichia coli (EC) and Streptococcus pneumoniae (SPN) and in non-HIV patients SA, EC, and Klebsiella pneumoniae (KP). While the rate of SA (25.3%–22.0%), SPN (2%–3%), and KP (10.2%–8.4%) remained stable during the study period, EC rate increased (18.5–25.7; P = 0.002). HIV patients were more likely to have the respiratory tract as the source of BSI.

Conclusion

HIV-patients remain at higher risk for SPN and to have a respiratory source of BSI but the top causes of BSI in patients with and without HIV are SA and EC. Whether the higher rate of SPN among HIV patients is related to poor compliance with vaccination or suboptimal immune status is uncertain. Further studies are needed to compare pneumococcal vaccination compliance rate in patients with or without HIV.

African Americans; vascular; Soft tissue/bone; urinary tract; respiratory.

Disclosures

All authors: No reported disclosures.

CAIDE Dementia Risk Score, Alzheimer and cerebrovascular pathology: a population-based autopsy study

BACKGROUND

CAIDE Dementia Risk Score is a tool for estimating dementia risk in the general population. Its longitudinal associations with Alzheimer or vascular neuropathology in the oldest old are not known.

AIM

To explore the relationship between CAIDE Dementia Risk Score at baseline and neuritic plaques, neurofibrillary tangles, cerebral infarcts and cerebral amyloid angiopathy (CAA) after up to 10-year follow-up in the Vantaa 85 +  population.

METHODS

Study population included 149 participants aged ≥85 years, without dementia at baseline, and with available clinical and autopsy data. Methenamine silver staining was used for β-amyloid and modified Bielschowsky method for neurofibrillary tangles and neuritic plaques. Macroscopic infarcts were identified from cerebral hemispheres, brainstem and cerebellum slices. Standardized methods were used to determine microscopic infarcts, CAA and α-synuclein pathologies. The CAIDE Dementia Risk Score was calculated based on scores for age, sex, BMI, total cholesterol, systolic blood pressure, physical activity and APOEε4 carrier status (range 0-18 points).

RESULTS

A CAIDE Dementia Risk Score above 11 points was associated with more cerebral infarctions up to 10 years later: OR (95% CI) was 2.10 (1.06-4.16). No associations were found with other neuropathologies.

CONCLUSION

In a population of elderly aged ≥85 years, higher CAIDE Dementia Risk Score was associated with increased risk of cerebral infarcts.

Homocysteine and Dementia: An International Consensus Statement

Identification of modifiable risk factors provides a crucial approach to the prevention of dementia. Nutritional or nutrient-dependent risk factors are especially important because dietary modifications or use of dietary supplements may lower the risk factor level. One such risk factor is a raised concentration of the biomarker plasma total homocysteine, which reflects the functional status of three B vitamins (folate, vitamins B12, B6). A group of experts reviewed literature evidence from the last 20 years. We here present a Consensus Statement, based on the Bradford Hill criteria, and conclude that elevated plasma total homocysteine is a modifiable risk factor for development of cognitive decline, dementia, and Alzheimer's disease in older persons. In a variety of clinical studies, the relative risk of dementia in elderly people for moderately raised homocysteine (within the normal range) ranges from 1.15 to 2.5, and the Population Attributable risk ranges from 4.3 to 31%. Intervention trials in elderly with cognitive impairment show that homocysteine-lowering treatment with B vitamins markedly slows the rate of whole and regional brain atrophy and also slows cognitive decline. The findings are consistent with moderately raised plasma total homocysteine (>11 μmol/L), which is common in the elderly, being one of the causes of age-related cognitive decline and dementia. Thus, the public health significance of raised tHcy in the elderly should not be underestimated, since it is easy, inexpensive, and safe to treat with B vitamins. Further trials are needed to see whether B vitamin treatment will slow, or prevent, conversion to dementia in people at risk of cognitive decline or dementia.

CT and MRI Findings in Cerebral Aspergilloma

PURPOSE

Invasive aspergillosis usually affects immunocompromised patients. It carries a high risk of morbidity and mortality and usually has a nonspecific clinical presentation. Early diagnosis is essential in order to start effective treatment and improve clinical outcome.

MATERIALS AND METHODS

In a retrospective search of the PACS databases from two medical centers, we identified 9 patients with histologically proven cerebral aspergilloma. We systematically analyzed CT and MRI imaging findings to identify typical imaging appearances of cerebral aspergilloma.

RESULTS

CT did not show a typical appearance of the aspergillomas. In 100 % (9/9) there was a rim-attenuated diffusion restriction on MRI imaging. Multiple hypointense layers in the aspergillus wall, especially on the internal side, were detected in 100 % on T2-weighted imaging (9/9). Aspergillomas were T1-hypointense in 66 % of cases (6/9) and partly T1-hyperintense in 33 % (3/9). In 78 % (7/9) of cases, a rim-attenuated diffusion restriction was detected after contrast agent application.

CONCLUSION

Nine cases were identified. Whereas CT features were less typical, we observed the following imaging features on MRI: A strong, rim-attenuated diffusion restriction (9/9); onion layer-like hypointense zones, in particular in the innermost part of the abscess wall on T2-weighted images (9/9). Enhancement of the lesion border was present in the majority of the cases (7/9).

KEY POINTS

· There are typical MRI imaging features of aspergillomas.. · However, these findings could be affected by the immune status of the patient.. · Swift identification of aspergilloma imaging patterns is essential to allow for adequate therapeutic decision making..

CITATION FORMAT

· Gärtner F, Forstenpointner J, Ertl-Wagner B et al. CT and MRI Findings in Cerebral Aspergilloma. Fortschr Röntgenstr 2018; 190: 967 - 970.

Association of Vitamin B12, Folate, and Sulfur Amino Acids With Brain Magnetic Resonance Imaging Measures in Older Adults: A Longitudinal Population-Based Study

IMPORTANCE

Vitamin B12, folate, and sulfur amino acids may be modifiable risk factors for structural brain changes that precede clinical dementia.

OBJECTIVE

To investigate the association of circulating levels of vitamin B12, red blood cell folate, and sulfur amino acids with the rate of total brain volume loss and the change in white matter hyperintensity volume as measured by fluid-attenuated inversion recovery in older adults.

DESIGN, SETTING, AND PARTICIPANTS

The magnetic resonance imaging subsample of the Swedish National Study on Aging and Care in Kungsholmen, a population-based longitudinal study in Stockholm, Sweden, was conducted in 501 participants aged 60 years or older who were free of dementia at baseline. A total of 299 participants underwent repeated structural brain magnetic resonance imaging scans from September 17, 2001, to December 17, 2009.

MAIN OUTCOMES AND MEASURES

The rate of brain tissue volume loss and the progression of total white matter hyperintensity volume.

RESULTS

In the multi-adjusted linear mixed models, among 501 participants (300 women [59.9%]; mean [SD] age, 70.9 [9.1] years), higher baseline vitamin B12 and holotranscobalamin levels were associated with a decreased rate of total brain volume loss during the study period: for each increase of 1 SD, β (SE) was 0.048 (0.013) for vitamin B12 (P < .001) and 0.040 (0.013) for holotranscobalamin (P = .002). Increased total homocysteine levels were associated with faster rates of total brain volume loss in the whole sample (β [SE] per 1-SD increase, -0.035 [0.015]; P = .02) and with the progression of white matter hyperintensity among participants with systolic blood pressure greater than 140 mm Hg (β [SE] per 1-SD increase, 0.000019 [0.00001]; P = .047). No longitudinal associations were found for red blood cell folate and other sulfur amino acids.

CONCLUSIONS AND RELEVANCE

This study suggests that both vitamin B12 and total homocysteine concentrations may be related to accelerated aging of the brain. Randomized clinical trials are needed to determine the importance of vitamin B12 supplementation on slowing brain aging in older adults.

Advances in the prevention of Alzheimer's disease and dementia

BACKGROUND

Definitions and diagnostic criteria for all medical conditions are regularly subjected to reviews and revisions as knowledge advances. In the field of Alzheimer's disease (AD) research, it has taken almost three decades for diagnostic nomenclature to undergo major re-examination. The shift towards presymptomatic and pre-dementia stages of AD has brought prevention and treatment trials much closer to each other than before.

METHODS

Here we discuss: (i) the impact of diagnostic reliability on the possibilities for developing preventive strategies for AD; (ii) the scientific evidence to support moving from observation to action; (iii) ongoing intervention studies; and (iv) the methodological issues and prospects for balancing strategies for high-risk individuals with those for broad population-based prevention.

RESULTS

The associations between neuropathology and cognition are still not entirely clear. In addition, the risk factors for AD dementia and the neuropathological hallmarks of AD may not necessarily be the same. Cognitive impairment has a clearer clinical significance and should therefore remain the main focus of prevention. Risk/protective factors for dementia/AD need to be studied from a life-course perspective. New approaches in prevention trials include enrichment strategies based on genetic risk factors or beta-amyloid biomarkers (at least four ongoing pharmacological trials), and multidomain interventions simultaneously targeting various vascular and lifestyle-related risk factors (at least three ongoing trials). Experience from prevention programmes in other chronic diseases can provide additional methodological improvements.

CONCLUSIONS

Building infrastructures for international collaborations is necessary for managing the worldwide public health problem of AD and dementia. The International Database on Aging and Dementia (IDAD) and the European Dementia Prevention Initiative (EDPI) are examples of ongoing international efforts aiming to improve the methodology of preventive studies and provide the basis for larger intervention trials.

Vitamin D in relation to cognitive impairment, cerebrospinal fluid biomarkers, and brain volumes

BACKGROUND

Low vitamin D status is associated with poorer cognitive function in older adults, but little is known about the potential impact on cerebrospinal fluid (CSF) biomarkers and brain volumes. The objective of this study was to examine the relations between plasma 25-hydroxyvitamin D (25(OH)D) and cognitive impairment, CSF biomarkers of Alzheimer's disease (AD), and structural brain tissue volumes.

METHODS

A total of 75 patients (29 with subjective cognitive impairment, 28 with mild cognitive impairment, 18 with AD) referred to the Memory Clinic at Karolinska University Hospital, Huddinge, Sweden were recruited. Plasma 25(OH)D, CSF levels of amyloid β (Aβ(1-42)), total-tau, and phosphorylated tau, and brain tissue volumes have been measured.

RESULTS

After adjustment for several potential confounders, the odds ratios (95% confidence interval) for cognitive impairment were as follows: 0.969 (0.948-0.990) per increase of 1 nmol/L of 25(OH)D and 4.19 (1.30-13.52) for 24(OH)D values less than 50 nmol/L compared with values greater than or equal to 50 nmol/L. Adjusting for CSF Aβ(1-42) attenuated the 25(OH)D-cognition link. In a multiple linear regression analysis, higher 25(OH)D levels were related to higher concentrations of CSF Aβ(1-42) and greater brain volumes (eg, white matter, structures belonging to medial temporal lobe). The associations between 25(OH)D and tau variables were not significant.

CONCLUSIONS

This study suggests that vitamin D may be associated with cognitive status, CSF Aβ(1-42) levels, and brain tissue volumes.

Plasma homocysteine, Alzheimer and cerebrovascular pathology: a population-based autopsy study

Elevated plasma total homocysteine is associated with increased risk of dementia/Alzheimer's disease, but underlying pathophysiological mechanisms are not fully understood. This study investigated possible links between baseline homocysteine, and post-mortem neuropathological and magnetic resonance imaging findings up to 10 years later in the Vantaa 85+ population including people aged ≥85 years. Two hundred and sixty-five individuals had homocysteine and autopsy data, of which 103 had post-mortem brain magnetic resonance imaging scans. Methenamine silver staining was used for amyloid-β and modified Bielschowsky method for neurofibrillary tangles and neuritic plaques. Macroscopic infarcts were identified from cerebral hemispheres, brainstem and cerebellum slices. Standardized methods were used to determine microscopic infarcts, cerebral amyoloid angiopathy, and α-synuclein pathology. Magnetic resonance imaging was used for visual ratings of the degree of medial temporal lobe atrophy, and periventricular and deep white matter hyperintensities. Elevated baseline homocysteine was associated with increased neurofibrillary tangles count at the time of death: for the highest homocysteine quartile, odds ratio (95% confidence interval) was 2.60 (1.28-5.28). The association was observed particularly in people with dementia, in the presence of cerebral infarcts, and with longer time between the baseline homocysteine assessment and death. Also, elevated homocysteine tended to relate to amyloid-β accumulation, but this was seen only with longer baseline-death interval: odds ratio (95% confidence interval) was 2.52 (0.88-7.19) for the highest homocysteine quartile. On post-mortem magnetic resonance imaging, for the highest homocysteine quartile odds ratio (95% confidence interval) was 3.78 (1.12-12.79) for more severe medial temporal atrophy and 4.69 (1.14-19.33) for more severe periventricular white matter hyperintensities. All associations were independent of several potential confounders, including common vascular risk factors. No relationships between homocysteine and cerebral macro- or microinfarcts, cerebral amyoloid angiopathy or α-synuclein pathology were detected. These results suggest that elevated homocysteine in adults aged ≥85 years may contribute to increased Alzheimer-type pathology, particularly neurofibrillary tangles burden. This effect seems to be more pronounced in the presence of cerebrovascular pathology. Randomized controlled trials are needed to determine the impact of homocysteine-lowering treatments on dementia-related pathology.

Associations between serum homocysteine, holotranscobalamin, folate and cognition in the elderly: a longitudinal study

OBJECTIVES

To examine the associations between serum homocysteine (tHcy), holotranscobalamin (holoTC, the biologically active fraction of vitamin B12) and folate and cognitive functioning in a longitudinal population-based study of Finnish elderly subjects.

SUBJECTS AND DESIGN

tHcy, holoTC and folate were measured at baseline in 274 dementia-free subjects aged 65-79years from the Cardiovascular Risk Factors, Aging and Dementia study. Subjects were re-examined 7years later, and global cognition, episodic memory, executive functioning, verbal expression and psychomotor speed were assessed.

RESULTS

Higher baseline tHcy levels were associated with poorer performance in global cognition, relative difference: 0.90 [95% confidence interval (CI) 0.81-0.99]; episodic memory: 0.87 (95% CI 0.77-0.99); executive functions: 0.86 (95% CI 0.75-0.98); and verbal expression: 0.89 (95% CI 0.81-0.97) at follow-up. Increased holoTC levels were related to better performance on global cognition: 1.09 (95% CI 1.00-1.19); executive functions: 1.11 (95% CI 1.01-1.21); and psychomotor speed: 1.13 (95% CI 1.01-1.26). After excluding 20 cases of incident dementia, increased tHcy remained associated with poorer performance in episodic memory, execution functions and verbal expression. Higher holoTC levels tended to be related to better performance in executive functions and psychomotor speed, while elevated serum folate concentrations were significantly related to higher scores in global cognition and verbal expression tests.

CONCLUSIONS

tHcy, holoTC and folate levels are related to cognitive performance 7years later even in nondemented elderly subjects. Randomized trials are needed to determine the impact of vitamin B12 and folate supplementation on preventing cognitive decline in the elderly.

Homocysteine and holotranscobalamin and the risk of Alzheimer disease: a longitudinal study

OBJECTIVE

To examine the relation between serum levels of homocysteine (tHcy) and holotranscobalamin (holoTC), the active fraction of vitamin B12, and risk of incident Alzheimer disease (AD) in a sample of Finnish community-dwelling elderly.

METHODS

A dementia-free sample of 271 subjects aged 65-79 years derived from the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study was followed up for 7 years to detect incident AD. The association between serum tHcy and holoTC with AD was analyzed with multiple logistic regression after adjusting for several potential confounders, including common vascular risk factors.

RESULTS

The odds ratios (ORs) (95% confidence interval [CI]) for AD were 1.16 (1.04-1.31) per increase of 1 μmol/L of tHcy at baseline and 0.980 (0.965-0.995) for each increase of 1 pmol/L baseline holoTC. Adjustment for several potential confounders including age, sex, education, APOE ε4 allele, body mass index, Mini-Mental State Examination, smoking, stroke, and blood pressure did not alter the associations: ORs (95% CI) for AD became 1.19 (1.01-1.39) for tHcy and 0.977 (0.958-0.997) for holoTC. Adjusting for holoTC attenuated the tHcy-AD link (OR changed from 1.16 to 1.10, 95% CI 0.96-1.25). The holoTC-AD relationship was less influenced by controlling for tHcy (OR changed from 0.980 to 0.984, 95% CI 0.968-1.000). Addition of folate did not change any of the results.

CONCLUSIONS

This study suggests that both tHcy and holoTC may be involved in the development of AD. The tHcy-AD link may be partly explained by serum holoTC. The role of holoTC in AD should be further investigated.

Interleukin-4 (C-590T) and interferon-gamma (G5644A) gene polymorphisms in patients with periodontitis

BACKGROUND AND OBJECTIVE

Periodontitis is a multifactorial disease and immunologic and genetic factors have an important role in its pathogenesis. Mutation in the promoter regions of the interleukin-4 and interferon-gamma genes has been reported to modify the protein expression. The objective of this study was to evaluate the possible role of interleukin-4 (C-590T) and interferon-gamma (G5644A) polymorphisms in the susceptibility to periodontitis.

MATERIAL AND METHODS

In this case-control study, 53 patients (36 women and 17 men), comprising 27 patients with aggressive periodontitis and 26 patients with chronic periodontitis, and 56 healthy volunteers, were enrolled. DNA was isolated from all subjects, and the polymerase chain reaction-sequence specific primer method was used to study the interleukin-4 (C-590T) and interferon-gamma (G5644A) gene polymorphisms.

RESULTS

Our results showed no significant difference in the allele and genotype frequencies of interleukin-4 (C-590T) and interferon-gamma (G5644A) gene polymorphisms between patients with periodontal disease and controls.

CONCLUSION

The results suggest that the interleukin-4 (C-590T) and interferon-gamma (G5644A) gene polymorphisms may not be associated with the susceptibility of Iranian individuals to periodontitis.

Comparison of miltefosine and meglumine antimoniate for the treatment of zoonotic cutaneous leishmaniasis (ZCL) by a randomized clinical trial in Iran

This study was a randomized, open label comparison that was designed to determine efficacy and safety of miltefosine as the first oral drug for the treatment of zoonotic cutaneous leishmaniasis caused by Leishmania major in comparison with meglumine antimoniate. Complete clinical response was defined as 100% re-epithelialization of the lesion. Definitions of lesion cure and failure were based on both clinical and parasitological criteria two weeks after the end of treatment and clinical recovery three months after this period. Of 32 patients enrolled for miltefosine treatment 28 patients completed treatment, of which 26 were cured at three months, corresponding to a cure rate of 92.9% on a per protocol analysis, and 81.3% according to intention to treat analysis. There was one failure (3.1%), one relapse (3.1%) and four dropouts due to lack of tolerability (12.5%) during the first week of treatment. Of 31 patients who received intramuscular meglumine antimoniate (20mgSb(5)/kg body weight daily for 14 days) 25 were cured (83.3% on a per protocol basis, 80.6% on intention to treat basis), five failed (16.1%) and one was lost (3.2%) at 3-month follow-up. At 6-month follow-up after the end of treatment, no relapse was observed. Both regimens were tolerated but averages of nausea (32.2%) and vomiting (21.5%) were observed in patients during two weeks after initiation of miltefosine treatment. Other gastrointestinal, musculoskeletal, and total adverse events were not statistically different in the two groups during one to four weeks after therapy initiation. No relevant changes were observed in levels of liver enzymes, creatinine and hematological tests before and after end of treatment in both groups. In conclusion, miltefosine is apparently at least as good as meglumine antimoniate for the treatment of cutaneous leishmaniasis caused by L. major in Iran, based on parasitological as well as clinical criteria two weeks, three months, and six months after end of treatment.

Evaluation of a Crimean-Congo hemorrhagic fever virus recombinant antigen expressed by Semliki Forest suicide virus for IgM and IgG antibody detection in human and animal sera collected in Iran

Crimean-Congo hemorrhagic fever virus (CCHFV) is transmitted to humans by ticks or by direct contact with infected blood. It causes severe, often fatal, hemorrhagic diseases in humans but infection in animals is asymptomatic. CCHFV can spread from person to person and has caused many nosocomial outbreaks. Because the virus is very pathogenic for humans it must be manipulated in a biosafety level 4 (BSL4) laboratory, rendering the production of antigen for serological diagnosis difficult. To replace the native antigen, we produced a recombinant nucleoprotein expressed in mammalian cells via the recombinant Semliki Forest alphavirus replicon and developed an indirect immunofluorescence assay (IFA) as well as an enzyme-linked immunosorbent assay (ELISA) by immunocapture to detect IgM and IgG in human and animal serum. Using these methods, we analyzed clinical samples from human patients and sera from domestic animals collected in Iran and we show that this novel antigen provides a novel, sensitive and specific tool for CCHF diagnosis.