The role of vitamin D deficiency in sepsis and potential therapeutic implications

Dietary patterns and micronutrients in respiratory infections including COVID-19: a narrative review

BACKGROUND

COVID-19 is a pandemic caused by nCoV-2019, a new beta-coronavirus from Wuhan, China, that mainly affects the respiratory system and can be modulated by nutrition.

METHODS

This review aims to summarize the current literature on the association between dietary intake and serum levels of micronutrients, malnutrition, and dietary patterns and respiratory infections, including flu, pneumonia, and acute respiratory syndrome, with a focus on COVID-19. We searched for relevant articles in various databases and selected those that met our inclusion criteria.

RESULTS

Some studies suggest that dietary patterns, malnutrition, and certain nutrients such as vitamins D, E, A, iron, zinc, selenium, magnesium, omega-3 fatty acids, and fiber may have a significant role in preventing respiratory diseases, alleviating symptoms, and lowering mortality rates. However, the evidence is not consistent and conclusive, and more research is needed to clarify the mechanisms and the optimal doses of these dietary components. The impact of omega-3 and fiber on respiratory diseases has been mainly studied in children and adults, respectively, and few studies have examined the effect of dietary components on COVID-19 prevention, with a greater focus on vitamin D.

CONCLUSION

This review highlights the potential of nutrition as a modifiable factor in the prevention and management of respiratory infections and suggests some directions for future research. However, it also acknowledges the limitations of the existing literature, such as the heterogeneity of the study designs, populations, interventions, and outcomes, and the difficulty of isolating the effects of single nutrients from the complex interactions of the whole diet.

Effect of calcitriol supplementation on infectious biomarkers in patients with positive systemic inflammatory response: A Randomized Controlled Trial

Background

Sepsis is one of the common causes of hospitalization of patients in intensive care units. A significant role for vitamin D in sepsis has been proposed, which is due to its active metabolite, calcitriol.

Aims

Evaluate the effect of calcitriol supplementation on infectious biomarkers, including procalcitonin and presepsin.

Methods

Patients with sepsis were divided into intervention and control group. Patients in the intervention group received intravenous calcitriol daily for 3 days. The serum levels of procalcitonin and presepsin were evaluated on days 0, 3, and 5 after administration.

Results

Fifty-two SIRS-positive patients were evaluated. Baseline characteristics, changes in Sequential Organ Failure Assessment (SOFA) score and blood levels of vitamin D were not significantly different between the two groups. Procalcitonin levels on day 5 and the differences between day 5 and 0 were significantly lower in the intervention group (P = 0.02). Presepsin on the third and fifth days in the intervention group was reduced, but in the control group, there was an ascending trend. However, there was no significant difference between the two groups on days 3 and 5 (P = 0.17 and P = 0.06, respectively) or between days 3 as well as 5 and the baseline presepsin level (P = 0.93 and P = 0.92, respectively). The ICU length of stay and 28-day mortality did not differ significantly either between the two arms of the study.

Conclusions

Finally, the results of this study showed that the administration of intravenous calcitriol could reduce the levels of procalcitonin but did not have a significant effect on presepsin.

Modifiable contributing factors to COVID-19: A comprehensive review

The devastating complications of coronavirus disease 2019 (COVID-19) result from an individual's dysfunctional immune response following the initial severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Multiple toxic stressors and behaviors contribute to underlying immune system dysfunction. SARS-CoV-2 exploits the dysfunctional immune system to trigger a chain of events ultimately leading to COVID-19. The current study identifies eighty immune system dysfunction-enabling toxic stressors and behaviors (hereafter called modifiable contributing factors (CFs)) that also link directly to COVID-19. Each CF is assigned to one of the five categories in the CF taxonomy shown in Section 3.3.: Lifestyle (e.g., diet, substance abuse); Iatrogenic (e.g., drugs, surgery); Biotoxins (e.g., micro-organisms, mycotoxins); Occupational/Environmental (e.g., heavy metals, pesticides); Psychosocial/Socioeconomic (e.g., chronic stress, lower education). The current study shows how each modifiable factor contributes to decreased immune system capability, increased inflammation and coagulation, and increased neural damage and neurodegeneration. It is unclear how real progress can be made in combatting COVID-19 and other similar diseases caused by viral variants without addressing and eliminating these modifiable CFs.

Score-based prediction model for severe vitamin D deficiency in patients with critical illness: development and validation

BACKGROUND

Severe vitamin D deficiency (SVDD) dramatically increases the risks of mortality, infections, and many other diseases. Studies have reported higher prevalence of vitamin D deficiency in patients with critical illness than general population. This multicenter retrospective cohort study develops and validates a score-based model for predicting SVDD in patients with critical illness.

METHODS

A total of 662 patients with critical illness were enrolled between October 2017 and July 2020. SVDD was defined as a serum 25(OH)D level of < 12 ng/mL (or 30 nmol/L). The data were divided into a derivation cohort and a validation cohort on the basis of date of enrollment. Multivariable logistic regression (MLR) was performed on the derivation cohort to generate a predictive model for SVDD. Additionally, a score-based calculator (the SVDD score) was designed on the basis of the MLR model. The model's performance and calibration were tested using the validation cohort.

RESULTS

The prevalence of SVDD was 16.3% and 21.7% in the derivation and validation cohorts, respectively. The MLR model consisted of eight predictors that were then included in the SVDD score. The SVDD score had an area under the receiver operating characteristic curve of 0.848 [95% confidence interval (CI) 0.781-0.914] and an area under the precision recall curve of 0.619 (95% CI 0.577-0.669) in the validation cohort.

CONCLUSIONS

This study developed a simple score-based model for predicting SVDD in patients with critical illness.

TRIAL REGISTRATION

ClinicalTrials.gov protocol registration ID: NCT03639584. Date of registration: May 12, 2022.

The Role of Vitamin D in SARS-CoV-2 Infection and Acute Kidney Injury

Vitamin D has been described as an essential nutrient and hormone, which can cause nuclear, non-genomic, and mitochondrial effects. Vitamin D not only controls the transcription of thousands of genes, directly or indirectly through the modulation of calcium fluxes, but it also influences the cell metabolism and maintenance specific nuclear programs. Given its broad spectrum of activity and multiple molecular targets, a deficiency of vitamin D can be involved in many pathologies. Vitamin D deficiency also influences mortality and multiple outcomes in chronic kidney disease (CKD). Active and native vitamin D serum levels are also decreased in critically ill patients and are associated with acute kidney injury (AKI) and in-hospital mortality. In addition to regulating calcium and phosphate homeostasis, vitamin D-related mechanisms regulate adaptive and innate immunity. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections have a role in excessive proinflammatory cell recruitment and cytokine release, which contribute to alveolar and full-body endothelial damage. AKI is one of the most common extrapulmonary manifestations of severe coronavirus disease 2019 (COVID-19). There are also some correlations between the vitamin D level and COVID-19 severity via several pathways. Proper vitamin D supplementation may be an attractive therapeutic strategy for AKI and has the benefits of low cost and low risk of toxicity and side effects.

Managing sepsis in the era of precision medicine: challenges and opportunities

INTRODUCTION

Precision medicine is a medical model in which decisions, practices, interventions and therapies are tailored to the individual patient based on their predicted response or risk of disease. Sepsis is a life-threatening condition characterized by immune system dysregulation whose pathophysiology remains incompletely understood. There is much hope that precision medicine can lead to better outcomes in patients with sepsis.

AREAS COVERED

In this review from a comprehensive literature search in PubMed for English-language studies conducted in adults, we highlight recent advances in the diagnosis and treatment of sepsis of bacterial origin in adults using precision medicine approaches including rapid diagnostic tests, predictive biomarkers, genomic methods, rapid antimicrobial susceptibility testing, and monitoring cell mediated immunity. Challenges and directions for future research are also discussed.

EXPERT OPINION

Current diagnostic testing in sepsis relies primarily on conventional cultures (e.g. blood cultures), which are time-consuming and may delay critical therapeutic decisions. Nonculture-based techniques including nucleic acid amplification technologies (NAAT), other molecular methods (biomarkers), and genomic sequencing offer promise to overcome some of the inherent limitations seen with culture-based techniques.

Potential roles of vitamin D binding protein in attenuating liver injury in sepsis

BACKGROUND

In sepsis, vitamin D binding protein (VDBP) has been shown to be low-expressed. The current study examined the relationship between serum VDBP level and liver injury in sepsis patients, as well as in a mouse model for sepsis and in cultured liver epithelial cell line exposed to lipopolysaccharide (LPS).

METHODS

The human study included 78 sepsis patients and 50 healthy volunteers. Sepsis patients were categorized into sepsis survivor group (n = 43) and sepsis non-survivor group (n = 35) based on 28-day mortality for data analysis. Adult male C57BL/6 mice were subjected to cecal ligation and puncture (CLP). Serum samples were collected on day 1, 3, 5 and 7 to determine the levels of VDBP, 25-hydroxyvitamin D [25(OH)D₃], 1,25-dihydroxyvitamin D [1,25(OH)₂D₃], interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α). Potential protective effects of VDBP overexpression against LPS-induced liver damage were examined in cultured THLE2 cells.

RESULTS

Serum levels of VDBP, 25(OH)D₃, and 1,25(OH)₂D₃ were significantly lower in sepsis patients vs. the healthy control (P < 0.001), as well as in the sepsis non-survivor group vs. the sepsis survivor group (P < 0.001, P = 0.0338, or P = 0.0013, respectively). Lower serum VDBP level was associated with higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (r = - 0.2565, P = 0.0234) and Sequential Organ Failure Assessment score (r = - 0.3522, P = 0.0016), but lower serum albumin (ALB, r = 0.4628, P < 0.001) and total protein (TP, r = 0.263, P = 0.02). In CLP mice, there was a 5-day period of serum VDBP reduction, followed by return towards the baseline on day 7. VDBP was also decreased in LPS-treated THLE2 cells (P < 0.001). VDBP overexpression reduced LPS-induced THLE2 damage. Reduced damage was associated with decreased oxidative stress and inactivation of the c-Jun N-terminal kinase signaling pathway.

CONCLUSION

VDBP may be protective against sepsis-induced liver injury.

Vitamin therapy in sepsis

Vitamins are essential micronutrients with key roles in many biological pathways relevant to sepsis. Some of these relevant biological mechanisms include antioxidant and anti-inflammatory effects, protein and hormone synthesis, energy generation, and regulation of gene transcription. Moreover, relative vitamin deficiencies in plasma are common during sepsis and vitamin therapy has been associated with improved outcomes in some adult and pediatric studies. High-dose intravenous vitamin C has been the vitamin therapy most extensively studied in adult patients with sepsis and septic shock. This includes three randomized control trials (RCTs) as monotherapy with a total of 219 patients showing significant reduction in organ dysfunction and lower mortality when compared to placebo, and five RCTs as a combination therapy with thiamine and hydrocortisone with a total of 1134 patients showing no difference in clinical outcomes. Likewise, the evidence for the role of other vitamins in sepsis remains mixed. In this narrative review, we present the preclinical, clinical, and safety evidence of the most studied vitamins in sepsis, including vitamin C, thiamine (i.e., vitamin B₁), and vitamin D. We also present the relevant evidence of the other vitamins that have been studied in sepsis and critical illness in both children and adults, including vitamins A, B₂, B₆, B₁₂, and E. IMPACT: Vitamins are key effectors in many biological processes relevant to sepsis. We present the preclinical, clinical, and safety evidence of the most studied vitamins in pediatric sepsis. Designing response-adaptive platform trials may help fill in knowledge gaps regarding vitamin use for critical illness and association with clinical outcomes.

Prevalence and Clinical Outcomes of Vitamin D Deficiency in COVID-19 Hospitalized Patients: A Retrospective Single-Center Analysis

Vitamin D attenuates inflammatory responses to viral respiratory infections. Hence, vitamin D deficiency may be a highly significant prognostic factor for severity and mortality in COVID-19 patients. To evaluate the complications and mortality in different vitamin D status groups in COVID-19 hospitalized patients, we conducted this retrospective study on 646 laboratory-confirmed COVID-19 patients who were hospitalized in Shahid Modarres Hospital, Tehran, Iran from 16th March 2020 until 25th February 2021. Overall, patients with vitamin D deficiency, insufficiency and sufficiency were 16.9%, 43.6% and 39.5%, respectively. The presence of comorbidity, length of hospitalization, ICU admission, and invasive mechanical ventilation requirement and overall complications were significantly more in patients with vitamin D deficiency (p-value < 0.001). 46.8% (51/109) of vitamin D deficient patients died due to the disease, whilst the mortality rate among insufficient and sufficient vitamin D groups was 29.4% (83/282) and 5.5% (14/255), respectively. In univariate analysis, age > 60 years (odds ratio (OR) = 6.1), presence of comorbidity (OR = 10.7), insufficient vitamin D status (OR = 7.2), and deficient vitamin D status (OR = 15.1) were associated with increase in COVID-19 mortality (p-value < 0.001). Finally, the multivariate analysis adjusted for age, sex, and comorbidities indicated vitamin D deficiency as an independent risk factor for mortality (OR = 3.3, p-value = 0.002). Vitamin D deficiency is a strong risk factor for mortality and severity of SARS-CoV-2 infection. Vitamin D supplementation may be able to prevent or improve the prognosis of COVID-19 during this pandemic.

MicroRNA-122 contributes to lipopolysaccharide-induced acute kidney injury via down-regulating the vitamin D receptor in the kidney

BACKGROUND

Our previous studies showed that vitamin D receptor (VDR) depletion promotes lipopolysaccharide (LPS)-induced acute kidney injury (AKI) in mice, and renal VDR is down-regulated in AKI, but the mechanism of VDR down-regulation is unclear.

METHODS

Nutritional vitamin D deficiency was induced by feeding mice a vitamin D-deficient (VD-D) diet. Mice were injected intraperitoneally with LPS (20 mg/kg) to establish LPS-induced AKI. Levels of VDR and miR-122 were measured both in vivo and in vitro. The associations between VDR and miR-122 were analysed by dual-luciferase reporter assays.

RESULTS

Compared with vitamin D-sufficient (VD-S) mice, VD-D mice developed more severe renal injury following LPS challenge. LPS induced a dramatic decrease in VDR expression and marked induction of miR-122 both in vivo and in vitro. Furthermore, miR-122 hairpin inhibitor alleviated LPS-induced VDR down-regulation whereas miR-122 mimic directly suppressed VDR expression in HK-2 cells. In luciferase reporter assays, miR-122 mimic was able to suppress luciferase activity in 293T cells co-transfected with a luciferase reporter that contains a putative miR-122 target site from 3'UTR of the VDR transcript, but not when this site was mutated. Moreover, miR-122 mimic significantly blocked paricalcitol-induced luciferase activity in 293T cells co-transfected with a VDRE-driven luciferase reporter, whereas miR-122 hairpin inhibitor enhanced paricalcitol's activity to suppress PUMA and caspase 3 activation induced by LPS in HK-2 cells.

CONCLUSIONS

Collectively, these studies provide evidence that miR-122 directly targets VDR in renal tubular cells, which strongly suggest that miR-122 up-regulation in the kidney under LPS challenge contributes to kidney injury by down-regulating VDR expression.

Nutritional supplementation of the pharmacotherapy of prostate diseases

Introduction: Nutritional supplementation is an integral part of modern pharmacotherapeutic strategies for prostate diseases with different levels of evidence for specific nutrients.

Provitamin A (beta-carotene), vitamin A (retinol) and prostate diseases. Their effects have not been sufficiently studied, and the available data are conflicting to recommend them as a nutritional supplement.

Vitamin E (tocopherol) and prostate diseases. Its effects have not been sufficiently studied, and the available data are conflicting to recommend it as a nutritional supplement.

Vitamin C (ascorbic acid) and prostate diseases. Its effects have not been sufficiently studied, and the available data are conflicted to recommend it as a nutritional supplement.

Vitamin K and prostate diseases. Its effects have not been sufficiently studied, and the available data are conflicted to recommend it as a nutritional supplement.

Vitamin D and prostate diseases. The evidence base of the vitamin D prostatotropic effects has been accumulated, which allows us to consider its deficiency replacement as an effective nutritional supplement in prostate diseases.

Omega-3 PUFAs and prostate diseases. They have universal physiological effects; however, the evidence base for their recommendation as a nutritional supplement for prostate diseases is still insufficient.

Zinc and prostate diseases. Positive effects of zinc on the prostate gland are known for a fact and allow us to recommend it as a nutritional supplement for prostate diseases.

Selenium and prostate diseases. The reliably proven positive effects of selenium on the prostate gland allow us to recommend it as a nutritional supplement for prostate diseases.

Magnesium and prostate diseases. Its effects have not been sufficiently studied, and the available data are conflicting to recommend it as a nutritional supplement.

Vitamin D deficiency as a risk factor for renal scarring in recurrent urinary tract infections

BACKGROUND

Renal scarring is a serious complication in recurrent urinary tract infections (UTIs). Vitamin D deficiency has also been reported to be a risk factor for UTIs although, to date, no association between vitamin D deficiency and renal scarring has yet been identified. In the present study, it was investigated whether vitamin D deficiency may be a risk factor for renal scarring in patients with recurrent UTIs.

METHODS

The study included patients between the ages of 1 and 18 years who were admitted to the pediatric nephrology department of the center between November 1, 2018 and November 1, 2019 and who were diagnosed with recurrent UTIs. The medical records of the patients were reviewed for the collection of demographic data, vitamin D levels, ultrasonography results and scintigraphic investigations with 99m-technetium dimercaptosuccinic acid (^99m Tc-DMSA). The patients were divided into two groups: those with and without renal scarring, diagnosed via ^99m Tc-DMSA. The vitamin D levels and other parameters of the two groups were compared.

RESULTS

Vitamin D deficiency (<20 ng/mL) was observed in 73.9% of the patients without renal scarring, and in 94.1% of those with renal scarring (P = 0.015). A logistic regression analysis revealed vitamin D deficiency to be an independent risk factor for renal scarring in patients with recurrent UTIs (OR = 0.796 [0.691-0.917]).

CONCLUSIONS

Vitamin D deficiency is found to be a risk factor for renal scarring in patients with recurrent UTIs. Vitamin D treatment may contribute to the prevention of renal scarring in patients with recurrent UTI.

Biologically active 1,25-dihydroxyvitamin D3 protects against experimental sepsis by negatively regulating the Toll-like receptor 4/myeloid differentiation primary response gene 88/Toll-IL-1 resistance-domain-containing adapter-inducing interferon-β signaling pathway

The hormonally active form of vitamin D (VD), 1,25‑dihydroxyvitamin D3, has been reported to be a key immunoregulator in the reduction of inflammation. In this study, we investigated the effects of VD in an experimental sepsis cell model, and the underlying mechanisms. The sepsis cell model was first established in monocytes, isolated from newborns and healthy adults, which were stimulation with lipopolysaccharide (LPS). We observed that cell viability was significantly impaired in the monocytes after LPS stimulation, using a Cell Counting Kit‑8 and trypan blue assays. Additionally, ELISA revealed that LPS stimulation significantly elevated the expression of interleukin 6 (IL‑6), IL‑10 and tumor necrosis factor‑α (TNF‑α). The expression levels of Toll‑like receptor (TLR4), myeloid differentiation primary response gene 88 (MyD88), and Toll‑IL‑1 resistance‑domain‑containing adapter‑inducing interferon‑β (TRIF) mRNA were also significantly elevated under LPS stimulation using reverse transcription‑quantitative PCR and western blot analysis. VD treatment could significantly suppress the effects of LPS simulation on monocytes by negatively regulating inflammatory cytokines and TLR4/MyD88/TRIF signaling. Furthermore, a regulatory feedback mechanism was proposed to involve TLR4, MyD88 and TRIF in the sepsis cell model. In conclusion, VD may effectively decrease the release of inflammatory cytokines by inhibiting the TLR4/MyD88/TRIF signaling pathway, could be considered as a potential therapeutic agent for the treatment of sepsis.

Venous Thromboembolism is Associated With Lack of Vitamin D Supplementation in Patients With Spinal Cord Injury and Low Vitamin D Levels

BACKGROUND

The role of vitamin D in the pathogenesis of venous thromboembolism (VTE) and prevalence of low vitamin D (LVitD) in spinal cord injury (SCI) has motivated vitamin D testing and supplementation. This is an exploratory study of data collected at a time before the routine clinical practice of vitamin D supplementation, allowing for evaluation of the natural history of vitamin D levels in patients with SCI.

OBJECTIVE

To determine if vitamin D supplementation in persons with SCI and LVitD levels is associated with decreased prevalence of VTE.

DESIGN

Retrospective cohort study.

SETTING

Rehabilitation Center at a Level I Trauma Center.

PARTICIPANTS

Patients with SCI admitted to acute inpatient rehabilitation (N = 282).

MAIN OUTCOME MEASURES

VTE prevalence in patients with LVitD levels, grouped by presence or absence of vitamin D supplementation.

RESULTS

Of the acute inpatient SCI population, 80% (227/282) of patients demonstrated vitamin D levels <30 ng/mL (LVitD). Although the incidence of VTE was almost double in the LVitD group, 19% (43/227) of the patients in the LVitD group had VTE versus 9% (5/55) of patients with vitamin D levels ≥30 ng/mL (normal VitD [NVitD]); this difference was not statistically significant (P = .108, Cramer's V = .104). When the role of vitamin D supplementation was analyzed, individuals in the LVitD group who received no vitamin D supplementation (LVitDSuppNegative) had a higher incidence of VTE (statistically significant) compared to the LVitD group with vitamin D supplementation (LVitDSuppPositive) (24% [42/178] vs. 2% [1/49]) (P < .001, Cramer's V = .226). In post hoc exploratory analyses, the VTE rate of patients in the LVitDSuppNegative group was noted to be significantly higher than that in all other patient groups combined (P < .001, Cramer's V = .229). A binary logistic regression model incorporating clinical covariates also showed this grouping to be significant.

CONCLUSION

A significant association appears to exist between lack of vitamin D supplementation and VTE occurrence in persons with acute SCI and LVitD levels.

LEVEL OF EVIDENCE

III.

Vitamin D and Postoperative Vasopressor Use in Cardiopulmonary Bypass

The use of cardiopulmonary bypass (CPB) in cardiac surgery often leads to a systemic inflammatory response. Up to 25% of patients undergoing CPB for cardiac surgery are reported to develop vasoplegic syndrome in the acute postoperative period, in which the patients are refractory to vasopressors. The purpose of this study is to assess vitamin D deficiency as a risk factor for vasoplegia after using CPB. We performed a retrospective review of 1322 patients undergoing adult cardiac surgery requiring CPB. Forty-six patients with previously recorded 25-hydroxy vitamin D (25(OH)D) levels within 6 months of surgery met the conditions of this study. The mean level of 25(OH)D was 32.7 ng/mL (standard deviation [SD] = 15.1). The mean age of patients was 67 (SD = 10.1) years old, most were male (63%) and white (78%). Average CPB time was 140 ± 44 minutes. Postoperative vasopressor use was compared to individual preoperative 25(OH)D levels. As a secondary end point, postoperative vasopressor use and vasoplegia were analyzed between 3 groups: Vitamin D deficient defined as 25(OH)D ≤20 ng/mL (n = 7), vitamin D insufficient defined as 25(OH)D between 20 and 29 ng/mL (n = 15), and vitamin D sufficient defined as 25(OH)D ≥30 ng/mL (n = 24). There was no correlation between vitamin D levels and postoperative vasopressor use. The mean doses of postoperative vasopressor use were 0.088 µg/kg/min (standard error of the mean [SEM] = 0.032), 0.085 µg/kg/min (SEM = 0.037), and 0.072 µg/kg/min (SEM = 0.024) of norepinephrine equivalents for the vitamin D deficient, insufficient, and sufficient groups, respectively. Incidence of vasoplegia for each group was the following: 0.143 for vitamin D deficient, 0.067 for vitamin D insufficient, and 0.125 for vitamin D sufficient. In this pilot study, there does not appear to be a relationship between vitamin D and vasopressor use following cardiac surgery utilizing CPB; however, there appears to be a trend toward an increased vasopressor usage in patients with decreased vitamin D levels. A larger sample size and a prospective analysis are warranted to further assess the significance of the relationship between vasoplegia and vitamin D deficiency. With further investigation, vitamin D has the potential to become a low-cost, low-risk therapeutic for improving outcomes in CPB surgery.

Serum concentrations of vitamin D and organ dysfunction in patients with severe sepsis and septic shock

Objectives

To evaluate the serum concentrations of vitamin D and their variations in patients with severe sepsis or septic shock and in control subjects upon admission and after 7 days of hospitalization in the intensive care unit and to correlate these concentrations with the severity of organ dysfunction.

Methods

This case-control, prospective, observational study involved patients aged > 18 years with severe sepsis or septic shock paired with a control group. Serum vitamin D concentrations were measured at inclusion (D0) and on the seventh day after inclusion (D7). Severe deficiency was defined as vitamin D levels < 10ng/ml, deficiency as levels between 10 and 20ng/ml, insufficiency as levels between 20 and 30ng/ml, and sufficiency as levels ≥ 30ng/mL. We considered a change to a higher ranking, together with a 50% increase in the absolute concentration, to represent an improvement.

Results

We included 51 patients (26 with septic shock and 25 controls). The prevalence of vitamin D concentration ≤ 30ng/ml was 98%. There was no correlation between the serum concentration of vitamin D at D0 and the SOFA score at D0 or D7 either in the general population or in the group with septic shock. Patients with improvement in vitamin D deficiency had an improved SOFA score at D7 (p = 0.013).

Conclusion

In the population studied, patients with septic shock showed improvement in the serum concentrations of vitamin D on the seventh day compared with the controls. We also found a correlation between higher vitamin D concentrations and a greater decrease in the severity of organ dysfunction.

Infants dying suddenly and unexpectedly share demographic features with infants who die with retinal and dural bleeding: a review of neural mechanisms

The cause of death in infants who die suddenly and unexpectedly (sudden unexpected death in infancy [SUDI]) remains a diagnostic challenge. Some infants have identified diseases (explained SUDI); those without explanation are called sudden infant death syndrome (SIDS). Demographic data indicate subgroups among SUDI and SIDS cases, such as unsafe sleeping and apparent life-threatening events. Infants dying suddenly with retinal and dural bleeding are often classified as abused, but in many there is no evidence of trauma. Demographic features suggest that they may represent a further subgroup of SUDI. This review examines the neuropathological hypotheses to explain SIDS and highlights the interaction of infant oxygen-conserving reflexes with the brainstem networks considered responsible for SIDS. We consider sex- and age-specific vulnerabilities related to dural bleeding and how sensitization of the dural innervation by bleeding may influence these reflexes, potentially leading to collapse or even death after otherwise trivial insults.

Evaluation of vitamin D levels in children with primary epistaxis

OBJECTIVE

This study aimed to investigate whether there is a relationship between 25-hydroxy vitamin D [25(OH)D 3] values and incidences of primary epistaxis among children.

METHODS

A total of 42 cases and 55 matched controls were included in our study. The study group and control group were well matched for age and gender. Age, gender, activated partial thromboplastin time (APTT) with reference to the international normalized ratio (INR), prothrombin time (PT), and 25(OH)D 3, parathormone (PTH), alkaline phosphatase (ALP), calcium (Ca), magnesium (Mg), and phosphorus (P) values were recorded for each participant.

RESULTS

Serum 25(OH) D values were found to be statistically significantly (P = 0.03) lower in children with primary epistaxis than in the healthy control group. Our study also revealed that 25(OH) D values were considerably (P < 0.001) lower in the group with primary epistaxis and upper respiratory tract infections (RTI) than in the group with primary epistaxis without upper RTI. Univariate logistic regression analyses demonstrated that 25(OH)D 3 < 20 ng/ml [odds ratio (OR) 1.117, 95% confidence interval (CI) (1.019-1.225); P = 0.019] and serum albumin level [OR 3.499, 95% CI (1072-11,426); P = 0.038] ratio were significantly related to primary epistaxis. Furthermore, multivariate logistic regression analyses revealed that 25(OH)D 3 < 20 ng/ml [OR 1.141, 95% CI (1047-1242); P = 0.003] and serum albumin level [OR 3.340, 95% CI (1068-10,446); P = 0.038] ratio were significantly related to primary epistaxis.

CONCLUSIONS

Many studies have revealed that vitamin D is a preventive and therapeutic agent for inflammation and infection, thereby providing benefits for children with primary epistaxis. In line with this, our study suggested that a patient's vitamin D status could also be important for the prevention of childhood primary epistaxis, although further studies are required to validate our findings.

[Vitamin D deficiency in children admitted to the paediatric intensive care unit]

INTRODUCTION

Vitamin D is essential for bone health, as well as for cardiovascular and immune function. In critically ill adults vitamin D deficiency (VDD) is common, and is associated with sepsis and higher critical illness severity.

OBJECTIVES

To establish the prevalence of VDD and its association with clinically relevant outcomes in children admitted to a Paediatric Intensive Care Unit (PICU) in Concepcion, Chile.

PATIENTS AND METHOD

Prospective observational cohort study in 90 consecutive children admitted to the PICU in a university general hospital. Blood was collected on admission to PICU and analysed for 25-OH-D levels. Severity of illness and vasopressor use were assessed using PRISM, PELOD, and vasoactive-inotropic score (VIS) score. VDD was defined as a serum 25-OH-D level<20ng/ml. Relative risks (RR) were calculated to determine the association between VDD and relevant clinical outcomes.

RESULTS

Mean (SD) serum vitamin D (25-OH-D) level in the cohort was 22.8 (1.0)ng/ml. The prevalence of VDD was 43.3%. VDD was associated with vasopressors use (RR1.6; 95%CI: 1.2-2.3; P<.01), mechanical ventilation (RR2.2; 95%CI: 1.2-3.9, P<.01), septic shock (RR1.9; 95%CI: 1.3-2.9, P<.001), and fluid bolus>40ml/kg in the first 24h of admission (RR 1.5; 95%CI: 1.1-2.1, P<.05).

CONCLUSIONS

In this study, VDD at PICU admission was prevalent in critically ill children and was associated with adverse clinical outcomes. Further studies are needed to assess the potential benefit of optimizing vitamin D status in the PICU.

Low serum 25-hydroxyvitamin D level and risk of urinary tract infection in infants

The aim of the study is to determine whether serum 25-hydroxyvitamin D (25(OH)D) deficiency in infants increased odds of urinary tract infection (UTI). A total of 238 infants including 132 patients experiencing a first episode of UTI and 106 controls, aged from 1 to 12 months, were enrolled. Serum 25(OH)D levels were tested through blood sampling. The serum 25(OH)D levels were significantly lower in cases with UTI than controls. The mean serum 25(OH)D levels were 29.09 ± 9.56 ng/mL in UTIs and 38.59 ± 12.41 ng/mL in controls (P < 0.001). Infants with acute pyelonephritis (APN) had lower serum 25(OH)D than those with lower UTI. The multivariate logistic regression analyses showed that serum 25(OH)D < 20 ng/mL (OR 5.619, 95% CI 1.469-21.484, P = 0.012) was positively related to an increased odds of UTI. Vitamin D supplementation (OR 0.298, 95% CI 0.150-0.591; P = 0.001) was associated with a decreased likelihood of UTI. Vitamin D deficiency in infants was associated with an increased odds of UTI. Interventional studies evaluating the role of vitamin D supplementation to reduce the burden of UTI are warranted.

Paricalcitol attenuates lipopolysaccharide-induced myocardial inflammation by regulating the NF-κB signaling pathway

Vitamin D deficiency is associated with an increased risk of cardiovascular disease, diabetes, colon and breast cancer, infectious diseases and allergies. Vascular alterations are an important pathophysiological mechanism of sepsis. Experimental data suggest that paricalcitol, a vitamin D2 analogue, exerts beneficial effects on renal inflammation and fibrosis. In the present study, we aimed to investigate the effects of paricalcitol on lipopolysaccharide (LPS)-induced myocardial inflammation and to elucidate the underlying mechanisms. We used primary cultured human umbilical vein endothelial cells for in vitro experiments, in which stimulation with tumor necrosis factor (TNF)-α was used to induce endothelial cell inflammation. For in vivo experiments, myocardial inflammation was induced by an intraperitoneal injection of 15 mg/kg LPS into C57BL6 mice pre-treated with or without 0.2 µg/kg paricalcitol. Treatment with paricalcitol suppressed the TNF-α-induced increase in the protein expression of intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and fractalkine in endothelial cells. Treatment with paricalcitol also decreased the TNF-α-induced nuclear factor (NF)-κB binding activity. In a mouse model of LPS-induced myocardial inflammation, pre-treatment with paricalcitol prevented the LPS-induced increase in the expression of myocardial ICAM-1, phosphorylated p65 and myocardial TNF-α. Pre-treatment with paricalcitol also alleviated endotoxemia‑induced microvascular leakage in the myocardium. The findings of our study suggest that paricalcitol exerts a protective effect against LPS-induced myocardial inflammation by regulating the expression of cell adhesion molecules and TNF-α, and by improving myocardial permeability.

The Association between Vitamin D Levels and Urinary Tract Infection in Children

AIM

We aimed to examine whether there is any association between serum levels of 25-hydroxyvitamin D [25(OH)D3] and urinary tract infection (UTI) among children.

METHODS

White blood cell count, serum C-reactive protein, calcium, phosphorus, alkaline phosphatase, parathormone, and serum 25(OH)D3 levels were measured in 82 children experiencing a first episode of UTI, with no risk factors for UTI, and 64 healthy control children.

RESULTS

The mean serum levels of 25(OH)D3 among children with UTI were significantly lower than those of controls (11.7 ± 3.3 vs. 27.6 ± 4.7 ng/ml; p < 0.001). The serum levels of 25(OH)D3 were significantly lower in patients with acute pyelonephritis compared to patients with lower UTI (8.6 ± 2.8 vs. 14.2 ± 3.0 ng/ml; p < 0.001). Within the study group, mean serum levels of 25(OH)D3 among girls were lower than those of boys (10.9 ± 3.4 ng/ml vs. 13.2 ± 4.4 ng/ml; p < 0.001). Multivariate analysis showed that a serum 25(OH)D3 level of <20 ng/ml (odds ratio 3.503, 95% confidence interval 1.621-7.571; p = 0.001) was associated with UTI in children.

CONCLUSIONS

Our results suggest that vitamin D deficiency may be a risk factor for UTI in children.

Serum levels of 25(OH)D are not associated with venous thromboembolism in the elderly population. A case-control study

The prevalence of both vitamin D deficiency and venous thromboembolism (VTE) is important in the elderly. Previous studies have provided evidence for a possible association between vitamin D status and the risk of VTE. Thus, we aimed to investigate the association between vitamin D levels and VTE in the population aged 75 and over included in the EDITH case-control study. The association between vitamin D status and VTE was analysed. We also analysed the monthly and seasonal variations of VTE and vitamin D. Between May 2000 and December 2009, 340 elderly patients (mean age 81.5 years, 32% men) with unprovoked VTE and their controls were included. The univariate and multivariate analysis found no significant association between serum levels of vitamin D and the risk of unprovoked VTE. In the unadjusted analysis, a higher BMI was statistically associated with an increased risk of VTE (OR 1.09; 95% CI 1.05-1.13) whereas a better walking capacity and living at home were associated with a decreased rate of VTE: OR 0.57; 95% CI 0.36-0.90 and 0.40; 95% CI 0.25-0.66, respectively. Although not significant, more VTE events occurred during winter (p=0.09). No seasonal variations of vitamin D levels were found (p=0.11). In conclusion, in contrast with previous reports our findings suggest that vitamin D is not associated with VTE in the elderly population.

Vitamin D Metabolites and Their Association with Calcium, Phosphorus, and PTH Concentrations, Severity of Illness, and Mortality in Hospitalized Equine Neonates

Background

Hypocalcemia is a frequent abnormality that has been associated with disease severity and outcome in hospitalized foals. However, the pathogenesis of equine neonatal hypocalcemia is poorly understood. Hypovitaminosis D in critically ill people has been linked to hypocalcemia and mortality; however, information on vitamin D metabolites and their association with clinical findings and outcome in critically ill foals is lacking. The goal of this study was to determine the prevalence of vitamin D deficiency (hypovitaminosis D) and its association with serum calcium, phosphorus, and parathyroid hormone (PTH) concentrations, disease severity, and mortality in hospitalized newborn foals.

Methods and Results

One hundred newborn foals ≤72 hours old divided into hospitalized (n = 83; 59 septic, 24 sick non-septic [SNS]) and healthy (n = 17) groups were included. Blood samples were collected on admission to measure serum 25-hydroxyvitamin D₃ [25(OH)D₃], 1,25-dihydroxyvitamin D₃ [1,25(OH) ₂D₃], and PTH concentrations. Data were analyzed by nonparametric methods and univariate logistic regression. The prevalence of hypovitaminosis D [defined as 25(OH)D₃ <9.51 ng/mL] was 63% for hospitalized, 64% for septic, and 63% for SNS foals. Serum 25(OH)D₃ and 1,25(OH) ₂D₃ concentrations were significantly lower in septic and SNS compared to healthy foals (P<0.0001; P = 0.037). Septic foals had significantly lower calcium and higher phosphorus and PTH concentrations than healthy and SNS foals (P<0.05). In hospitalized and septic foals, low 1,25(OH)₂D₃ concentrations were associated with increased PTH but not with calcium or phosphorus concentrations. Septic foals with 25(OH)D₃ <9.51 ng/mL and 1,25(OH) ₂D₃ <7.09 pmol/L were more likely to die (OR=3.62; 95% CI = 1.1-12.40; OR = 5.41; 95% CI = 1.19-24.52, respectively).

Conclusions

Low 25(OH)D₃ and 1,25(OH)₂D₃ concentrations are associated with disease severity and mortality in hospitalized foals. Vitamin D deficiency may contribute to a pro-inflammatory state in equine perinatal diseases. Hypocalcemia and hyperphosphatemia together with decreased 1,25(OH)₂D₃ but increased PTH concentrations in septic foals indicates that PTH resistance may be associated with the development of these abnormalities.

Vitamin D deficiency is an independent risk factor for urinary tract infections after renal transplants

Vitamin D deficiency is frequently found in patients with renal transplants (RTxs). Because vitamin D plays indispensable roles in the immune system, there may be an association between vitamin D deficiency and infection in these patients, but this has not been fully elucidated. Therefore, this study investigated the impact of pre-RTx vitamin D deficiency on urinary tract infection (UTI) development after RTx.We measured 25-hydroxyvitamin D3 (25(OH)D3) levels in 410 patients 2 weeks before they underwent RTx. Vitamin D deficiency was defined as 25(OH)D3 <10 ng/mL. The primary outcome was UTI occurrence after RTx. Cox proportional hazard analysis determined whether vitamin D deficiency was independently associated with UTI.The mean 25(OH)D3 level was 12.8 ± 6.9 ng/mL, and 171 patients (41.7%) were vitamin D deficient. During a median follow-up duration of 7.3 years, the UTI incidence was significantly higher in vitamin D-deficient patients (52 patients, 30.4%) compared with vitamin D-nondeficient patients (40 patients, 16.7%) (P = 0.001). Moreover, multivariate Cox proportional hazard analysis showed that vitamin D deficiency was an independent predictor of UTI after RTx (hazard ratio 1.81, 95% confidence interval 1.11-2.97, P = 0.02).Vitamin D deficiency was an independent risk factor for UTI after RTx; hence, determining 25(OH)D3 levels might help to predict infectious complications after RTx.

An update on the association of vitamin D deficiency with common infectious diseases

Vitamin D plays an important role in modulating the immune response to infections. Deficiency of vitamin D is a common condition, affecting both the general population and patients in health care facilities. Over the last decade, an increasing body of evidence has shown an association between vitamin D deficiency and an increased risk for acquiring several infectious diseases, as well as poorer outcomes in vitamin D deficient patients with infections. This review details recent developments in understanding the role of vitamin D in immunity, the antibacterial actions of vitamin D, the association between vitamin D deficiency and common infections (like sepsis, pneumonia, influenza, methicillin-resistant Staphylococcus aureus, human immunodeficiency virus type-1 (HIV), and hepatitis C virus (HCV)), potential therapeutic implications for vitamin D replacement, and future research directions.

Randomized controlled trial of calcitriol in severe sepsis

RATIONALE

Vitamin D and its metabolites have potent immunomodulatory effects in vitro, including up-regulation of cathelicidin, a critical antimicrobial protein.

OBJECTIVES

We investigated whether administration of 1,25-dihydroxyvitamin D (calcitriol) to critically ill patients with sepsis would have beneficial effects on markers of innate immunity, inflammation, and kidney injury.

METHODS

We performed a double-blind, randomized, placebo-controlled, physiologic study among 67 critically ill patients with severe sepsis or septic shock. Patients were randomized to receive a single dose of calcitriol (2 μg intravenously) versus placebo. The primary outcome was plasma cathelicidin protein levels assessed 24 hours after study drug administration. Secondary outcomes included leukocyte cathelicidin mRNA expression, plasma cytokine levels (IL-10, IL-6, tumor necrosis factor-α, IL-1β, and IL-2), and urinary kidney injury markers.

MEASUREMENTS AND MAIN RESULTS

Patients randomized to calcitriol (n = 36) versus placebo (n = 31) had similar plasma cathelicidin protein levels at 24 hours (P = 0.16). Calcitriol-treated patients had higher cathelicidin (P = 0.04) and IL-10 (P = 0.03) mRNA expression than placebo-treated patients 24 hours after study drug administration. Plasma cytokine levels (IL-10, IL-6, tumor necrosis factor-α, IL-1β, and IL-2) and urinary kidney injury markers were similar in calcitriol- versus placebo-treated patients (P > 0.05 for all comparisons). Calcitriol had no effect on clinical outcomes nor were any adverse effects observed.

CONCLUSIONS

Calcitriol administration did not increase plasma cathelicidin protein levels in critically ill patients with sepsis and had mixed effects on other immunomodulatory markers. Additional phase II trials investigating the dose and timing of calcitriol as a therapeutic agent in specific sepsis phenotypes may be warranted. Clinical trial registered with www.clinicaltrials.gov (NCT 01689441).

The immediate protective response to microbial challenge

The innate immune system detects infection and tissue injury through different families of pattern-recognition receptors (PRRs), such as Toll-like receptors. Most PRR-mediated responses initiate elaborate processes of signaling, transcription, translation, and secretion of effector mediators, which together require time to achieve. Therefore, PRR-mediated processes are not active in the early phases of infection. These considerations raise the question of how the host limits microbial replication and invasion during this critical period. Here, we examine the crucial defense mechanisms, such as antimicrobial peptides or extracellular traps, typically activated within minutes of the initial infection phase, which we term the "immediate protective response". Deficiencies in different components of the immediate protective response are often associated with severe and recurrent infectious diseases in humans, highlighting their physiologic importance.

Vitamin D Binding Protein Impact on 25-Hydroxyvitamin D Levels under Different Physiologic and Pathologic Conditions

There is a high prevalence of vitamin D deficiency worldwide, but how to define vitamin D deficiency is controversial. Currently, the plasma concentration of total 25-hydroxyvitamin D [25(OH)D] is considered an indicator of vitamin D status. The free hormone hypothesis states that protein-bound hormones are inactive while unbound hormones are free to exert biological activity. The majority of circulating 25(OH)D and 1,25(OH)2D is tightly bound to vitamin D binding protein (DBP), 10-15% is bound to albumin, and less than 1% of circulating vitamin D exists in an unbound form. While DBP is relatively stable in most healthy populations, a recent study showed that there are gene polymorphisms associated with race and ethnicity that could alter DBP levels and binding affinity. Furthermore, in some clinical situations, total vitamin D levels are altered and knowing whether DBP is also altered may have treatment implications. The aim of this review is to assess DBP concentration in different physiological and pathophysiological conditions. We suggest that DBP should be considered in the interpretation of 25(OH)D levels.

Potential benefits of vitamin D supplementation in critically ill patients

AIM

To review potential benefits of vitamin D supplementation in critically ill patients.

METHODS

The data were collected by searching Scopus, PubMed/Medline, ScienceDirect, Clinical trials and Cochrane database systematic reviews. The keywords used as search terms were 'vitamin D', 'critically ill patients', 'ICU' and 'sepsis'.

RESULTS & CONCLUSION

Vitamin D deficiency is common in patients admitted to emergency departments, medical and surgical intensive care units. Positive effects of vitamin D on the immune system through decreasing inflammatory cytokines and increasing natural anti-infective molecules have been reported. Patients with low serum vitamin D concentrations experienced longer hospital stay and were more prone to nosocomial infections, including blood stream and respiratory infections. However, a correlation between vitamin D serum level and patients' mortality is not fully described. Limited studies have assessed effects of vitamin D supplementation on morbidity and mortality in critically ill patients. In the future, well-designed randomized clinical trials should describe the best dose, route and duration of vitamin D supplementation in critically ill patients.

Is vitamin d insufficiency associated with mortality of critically ill patients?

Objective. To evaluate the vitamin D status of our critically ill patients and its relevance to mortality. Patients and Methods. We performed a prospective observational study in the medical intensive care unit of a university hospital between October 2009 and March 2011. Vitamin D levels were measured and insufficiency was defined as <20 ng/mL. Results. Two hundred and one patients were included in the study. The median age was 66 (56–77) and the majority of patients were male (56%). The median serum level of vitamin D was 14,9 ng/mL and 139 (69%) patients were vitamin D insufficient on admission. While we grouped the ICU patients as vitamin D insufficient and sufficient, vitamin D insufficient patients had more severe acute diseases and worse laboratory values on admission. These patients had more morbidities and were exposed to more invasive therapies during stay. The mortality rate was significantly higher in the vitamin D insufficient group compared to the vitamin D sufficient group (43% versus 26%, P = 0,027). However, logistic regression analysis demonstrated that vitamin D insufficiency was not an independent risk factor for mortality. Conclusion. Vitamin D insufficiency is common in our critically ill patients (69%), but it is not an independent risk factor for mortality.

Vitamin D deficiency and sudden unexpected death in infancy and childhood: a cohort study

We sought to (1) determine if there is an increased prevalence of vitamin D deficiency (VDD) in cases of sudden death in infancy and childhood; (2) establish whether there is a link between VDD and infection; and (3) assess if the level of vitamin D can be related to abnormalities in the skeletal survey and rib histology in our cohort. The postmortem reports of cases in which vitamin D levels were measured in 2009 and 2010 were retrieved. When parental consent for audit had been granted, rib histology and skeletal surveys were reviewed. Plasma 25-hydroxyvitamin D levels were measured in 41 postmortem cases. Ten (24.5%) had adequate levels, 5 (12%) had suboptimal levels, 16 (39%) had moderate deficiency, and 10 (24.5%) had severe deficiency. We had only 4 cases with VDD and infection. There were 25 cases of unexplained death in our cohort, and 76% of these had inadequate vitamin D levels. The rib histology was abnormal in 69% of cases that had inadequate vitamin D levels, while the radiology was abnormal in 19% of cases. A significant proportion of infants and children who died suddenly and unexpectedly had inadequate levels of vitamin D. We were unable to confirm or exclude an association between VDD and infection due to the small number of cases with confirmed infection. Further multicenter studies are needed to confirm our findings and explore possible associations between VDD and other known risk factors for sudden unexplained death in infancy and childhood.

Vitamin D effects on musculoskeletal health, immunity, autoimmunity, cardiovascular disease, cancer, fertility, pregnancy, dementia and mortality-a review of recent evidence

BACKGROUND

Optimal vitamin D intake and its status are important not only for bone and calcium-phosphate metabolism, but also for overall health and well-being. Vitamin D deficiency and insufficiency as a global health problem are likely to be a risk for wide spectrum of acute and chronic illnesses.

METHODS

A review of randomized controlled trials, meta-analyses, and other evidence of vitamin D action on various health outcomes.

RESULTS

Adequate vitamin D status seems to be protective against musculoskeletal disorders (muscle weakness, falls, fractures), infectious diseases, autoimmune diseases, cardiovascular disease, type 1 and type 2 diabetes mellitus, several types of cancer, neurocognitive dysfunction and mental illness, and other diseases, as well as infertility and adverse pregnancy and birth outcomes. Vitamin D deficiency/insufficiency is associated with all-cause mortality.

CONCLUSIONS

Adequate vitamin D supplementation and sensible sunlight exposure to reach optimal vitamin D status are among the front line factors of prophylaxis for the spectrum of disorders. Supplementation guidance and population strategies for the eradication of vitamin D deficiency must be included in the priorities of physicians, medical professionals and healthcare policy-makers.

Relationship between mean platelet volume and low-grade systemic coagulation with vitamin D deficiency in primary ovarian insufficiency

OBJECTIVE

Premature menopause in young women is associated with an increased incidence of cardiovascular disease. The present study was designed to determine vitamin D (vit D) and the coagulation parameters such as activated partial thromboplastin time (APTT), PT, D-dimer, white blood cell (WBC), and mean platelet volume (MPV) levels, in primary ovarian insufficiency (POI) patients and control women with a normal menstrual cycle.

MATERIALS AND METHODS

A total of 43 patients with non-diabetic POI were studied in order to evaluate and compare with the control group comprising 33 women with a normal menstrual cycle.

RESULTS

There was no significant difference between the groups for age and body mass index (BMI). D-dimer, WBC, MPV, PT, total cholesterol, and LDL cholesterol were higher in women with POI. APTT levels were also increased but missed the significance in POI group. Women with POI had significantly lower serum vit D levels compared with healthy control group. FSH level was positively correlated with D-dimer, WBC, MPV, and negatively correlated to vit D and serum D vit level was inversely correlated with MPV, APTT, D-dimer, FSH levels in individual women.

CONCLUSIONS

The obtained results seem to indicate that POI patients had low-grade systemic coagulation and fibrinolytic activation as evidenced by elevated D-dimer, WBC, MPV, PT values potentially be used as indicators of risk factor for thrombosis and atherosclerosis in POI women. All of our patients with POI were deficient in vit D. These results also suggest that vit D deficiency plays important roles of POI women and associated with coagulation, independently from age and BMI.

Vitamin D's potential to reduce the risk of hospital-acquired infections

Health care–associated and hospital-acquired infections are two entities associated with increased morbidity and mortality. They are highly costly and constitute a great burden to the health care system. Vitamin D deficiency (< 20 ng/ml) is prevalent and may be a key contributor to both acute and chronic ill health. Vitamin D deficiency is associated with decreased innate immunity and increased risk for infections. Vitamin D can positively influence a wide variety of microbial infections.

Herein we discuss hospital-acquired infections, such as pneumonia, bacteremias, urinary tract and surgical site infections, and the potential role vitamin D may play in ameliorating them. We also discuss how vitamin D might positively influence these infections and help contain health care costs. Pending further studies, we think it is prudent to check vitamin D status at hospital admission and to take immediate steps to address existing insufficient 25-hydroxyvitamin D levels.

The immunoregulatory function of vitamin D: implications in chronic kidney disease

Cardiovascular and infectious diseases remain the most common causes of death among patients with chronic kidney disease (CKD) and end-stage renal disease (ESRD). Basic science and epidemiological studies indicate that vitamin D has importance not only for cardiovascular health, but also for the immune response. Vitamin D signaling pathways regulate both innate and adaptive immunity, maintaining the associated inflammatory response within physiological limits. Levels of both the inactive as well as active form of vitamin D (25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, respectively) are decreased in patients with CKD and ESRD. It is reasonable to hypothesize, therefore, that the immune dysfunction associated with vitamin D deficiency in patients with CKD and ESRD in part explains the misdirected inflammatory response and increased susceptibility to infection seen in this population. Indeed, observational studies show that vitamin D deficiency in patients with ESRD is associated with increased mortality, and treatment with vitamin D is associated with a decreased risk of infection, as well as reduced all-cause mortality. However, whether different vitamin D preparations have differential effects on physiological function and clinical outcomes is still unclear. A proper understanding of the immune regulatory function of vitamin D is important for the development of future therapeutic strategies.