Alterations in vitamin D status and anti-microbial peptide levels in patients in the intensive care unit with sepsis

Serum levels of peptide cathelicidin LL-37 in elderly patients with depression

Cathelicidin LL-37 is a small cationic that plays an important role in antimicrobial defense, as it kills a broad spectrum of infectious agents by disrupting their membranes, including gram-positive and gram-negative bacteria, some viruses and fungi; and it neutralizes activity of bacterial endotoxins. Moreover, cathelicidin LL-37 exerts proinflammatory effect, while numerous reports indicate the role of inflammation in the development of depression. The purpose of this study was to evaluate the circulating levels of cathelicidin LL-37 in elderly depressed patients. Thirty-nine elderly (age ≥ 60 years) women with major depressive disorder and thirty-eight non-depressed elderly (age ≥ 60 years) women were included into the study. The mean serum cathelicidin LL-37 concentration in patients with depression and in healthy subjects were 2.40 ± 3.00ng/mL and 1.17 ± 3.04ng/mL, respectively, and the difference was statistically significant. No significant differences between mean serum CRP level and WBC count in MDD patients and control group were documented. There were no correlations between LL-37 level and age, BMI, GDS score, CRP level or WBC count. It can be assumed that elevated serum LL-37 levels in depressed patients may reflect inflammatory activation associated with depression.

Altered blood levels of vitamin D, cathelicidin and parathyroid hormone in patients with sepsis-a pilot study

It has been recognised that vitamin D (VitD) has a potential role in the regulation of inflammation and protection from infection. In a prospective clinical observational pilot study, we investigated the serum levels of 25-hydroxyvitamin-D3 (25(OH)D3), 1,25-hydroxyvitamin-D3 (1,25(OH)2D3), parathyroid hormone (PTH), and cathelicidin in intensive care unit (ICU) patients with or without systemic inflammatory response syndrome (SIRS). We included 32 patients with SIRS (septic patients), 16 ICU patients without SIRS, and 16 healthy controls. To substantiate the findings of the clinical study, we stimulated monocyte-derived macrophages with microbial patterns and analysed the impact of VitD on release of cytokines and antimicrobial activity. We found that patients with or without SIRS had relatively low levels of 25(OH)D3 and 1,25(OH)2D3. Patients with sepsis had significantly lower levels of 25(OH)D3 as compared to ICU control patients and healthy controls (10.53 ± 11.3 µg/l versus 16.46 ± 12.58 µg/l versus 24.04 ± 12.07 µg/l); the same was true for 1,25(OH)2D3. Serum levels of PTH and cathelicidin were significantly increased in sepsis patients, as compared to the other groups. In vitro, VitD significantly decreased the release of pro-inflammatory cytokines from macrophages and increased the antimicrobial activity of the cells. We concluded that patients with sepsis have significantly lower VitD levels. In vitro, VitD modulates inflammation and increases the antibacterial activity of innate immune cells. These findings suggest that VitD insufficiency is mechanistically related to increased susceptibility to SIRS and sepsis.

Serum Vitamin D Level at ICU Admission and Mortality

OBJECTIVE

Vitamin D is a fat-soluble vitamin that plays a major role in the regulation of bone and calcium metabolism and has effects on the immune and cardiovascular systems. Vitamin D deficiency is commonly seen in the general population as well as in critically ill patients and is reported to be associated with increased mortality and morbidity. Our aim was to determine the relationship between vitamin D level at ICU admission and mortality.

METHODS

A total of 491 patients admitted to the ICU between January 2014 and January 2015 were evaluated retrospectively. The patients who were under 18 years old, had elective surgery, or whose serum vitamin D levels and outcomes were unknown were excluded. The patient's age, gender, APACHE II score, number of organ dysfunction, serum vitamin D level at ICU admission and outcomes were recorded.

RESULTS

Vitamin D level was low (<25 ng dL^-1) in 166 (77.1%) of the patients. In non-survivor patients, APACHE II score and the number of organ dysfunction were significantly higher than the survivor patients (p<0.001 and p<0.001). There was a negative correlation between vitamin D level and APACHE II score (r²=0.04, p=0.006). In multivariate analyses, the likelihood of mortality was increased 9.8-fold (range 4.2-17.6) and 8.9-fold (range 3.9-14.1) with an APACHE II score ≥24 and the number of organ dysfunction ≥2, respectively (p<0.001 and p<0.001).

CONCLUSION

Vitamin D deficiency is commonly seen in intensive care patients. Although it is not an independently decisive factor for mortality, it might be related with poor clinical status at ICU admission. The APACHE II score and number of organ dysfunction are still important parameters for increased mortality.

Serum 25-hydroxyvitamin D concentrations in dogs with suspected acute pancreatitis

The present study aimed to determine whether circulating serum concentrations of 25-hydroxyvitamin D [25-(OH) D] differed between healthy dogs and dogs with acute pancreatitis (AP). Twenty-two healthy dogs and twenty client-owned dogs with AP were enrolled in the study. Serum concentrations of 25-(OH) D, blood ionized calcium (iCa), and serum C-reactive protein (CRP) were measured. Concentrations of serum 25-(OH) D and blood iCa in dogs with AP were significantly lower than those of healthy dogs, and serum concentrations of CRP in dogs with AP were significantly higher than those of healthy dogs. A significant difference in 25-(OH) D serum concentrations was observed between survivor and non-survivor dogs with AP. After resolution of clinical signs, concentrations of serum 25-(OH) D, blood iCa, and serum CRP did not differ compared to those before treatment. This study shows that dogs with AP exhibit decreased 25-(OH) D levels, which might be associated with calcium imbalances and mortality rate in canine AP.

Despite Inflammation, Supplemented Essential Amino Acids May Improve Circulating Levels of Albumin and Haemoglobin in Patients after Hip Fractures

Essential amino acids (EAAs) are nutritional substrates that promote body protein synthesis; thus we hypothesised that their supplementation may improve circulating albumin (Alb) and haemoglobin (Hb) in rehabilitative elderly patients following hip fractures (HF). Out of the 145 HF patients originally enrolled in our study, 112 completed the protocol. These subjects were divided into two randomised groups, each containing 56 patients. For a period of two months, one group (age 81.4 ± 8.1 years; male/female 27/29) received a placebo, and the other (age 83.1 ± 7.5 years; male/female 25/31) received 4 + 4 g/day oral EAAs. At admission, the prevalence of both hypoAlb (<3.5 g/dL) and hypoHb (<13 g/dL male, <12 g/dL female) was similar in the placebo group (64.3% hypoAlb, 66% hypoHb) and the treated group of patients (73.2% hypoAlb, 67.8% hypoHb). At discharge, however, the prevalence of hypoAlb had reduced more in EAAs than in placebo subjects (31.7% in EAAs vs. 77.8% in placebo; p < 0.001). There was a 34.2% reduction of anaemia in hypoHb in EAA subjects and 18.9% in placebo subjects, but the difference was not statistically significant. Oral supplementation of EAAs improves hypoAlb and, to a lesser extent, Hb in elderly rehabilitative subjects with hip fractures. Anaemia was reduced in more than one third of patients, which, despite not being statistically significant, may be clinically relevant.

Vitamin D Deficiency in Human and Murine Sepsis

Supplemental Digital Content is available in the text.

Objectives:

Vitamin D deficiency has been implicated as a pathogenic factor in sepsis and ICU mortality but causality of these associations has not been demonstrated. To determine whether sepsis and severe sepsis are associated with vitamin D deficiency and to determine whether vitamin D deficiency influences the severity of sepsis.

Design, Setting, and Patients:

Sixty-one patients with sepsis and severe sepsis from two large U.K. hospitals and 20 healthy controls were recruited. Murine models of cecal ligation and puncture and intratracheal lipopolysaccharide were undertaken in normal and vitamin D deficient mice to address the issue of causality.

Measurements and Main Results:

Patients with severe sepsis had significantly lower concentrations of 25-hydroxyvitamin D₃ than patients with either mild sepsis or age-matched healthy controls (15.7 vs 49.5 vs 66.5 nmol/L; p = 0.0001). 25-hydroxyvitamin D₃ concentrations were significantly lower in patients who had positive microbiologic culture than those who were culture negative (p = 0.0023) as well as those who died within 30 days of hospital admission (p = 0.025). Vitamin D deficiency in murine sepsis was associated with increased peritoneal (p = 0.037), systemic (p = 0.019), and bronchoalveolar lavage (p = 0.011) quantitative bacterial culture. This was associated with reduced local expression of the cathelicidin-related antimicrobial peptide as well as evidence of defective macrophage phagocytosis (p = 0.029). In the intratracheal lipopolysaccharide model, 1,500 IU of intraperitoneal cholecalciferol treatment 6 hours postinjury reduced alveolar inflammation, cellular damage, and hypoxia.

Conclusions:

Vitamin D deficiency is common in severe sepsis. This appears to contribute to the development of the condition in clinically relevant murine models and approaches to correct vitamin D deficiency in patients with sepsis should be developed.

LL-37-induced human mast cell activation through G protein-coupled receptor MrgX2

Human LL-37 is an important class of cationic antimicrobial peptide (CAP) that is known to stimulate mast cell activation. While many studies have been conducted on LL-37, to date little is known about the functional receptors for LL-37-induced human mast cell activation, in particular in terms of the release of de novo synthesized mediators. Thus, the aim of the present study is to identify the functional receptors for LL-37-induced human mast cell activation in terms of the degranulation and release of de novo synthesized mediators and investigate the downstream signalling pathways involved in mast cell activation. Overall, our study importantly demonstrates that LL-37-induced human mast cell degranulation and release of de novo synthesized mediators function primarily through the activation of MrgX2. We furthermore show that LL-37-induced human mast cell line LAD2 cells are involved in the degranulation and release of IL-8, and that FPRL1 and P2X7 have only a partial effect on IL-8 release, and no effect on mast cell degranulation triggered by LL-37. Instead, we find that silencing the expression of MrgX2 in human mast cell significantly inhibits the LL-37-induced degranulation and release of IL-8. Overall, this effect is associated with the activation of the G_i protein, PLC/PKC/Calcium/NFAT, PI3K/Akt and MAPKs signalling pathways.

Neonatal and Maternal 25-OH Vitamin D Serum Levels in Neonates with Early-Onset Sepsis

Vitamin D is a fat-soluble vitamin that is important for calcium metabolism and plays an important role in the immune functions. The aim of this study was to measure neonatal and maternal 25-OH vitamin D serum levels in neonates with early onset sepsis. The study included fifty neonates with early onset sepsis (25 full-term and 25 preterm infants) and thirty age and sex matched healthy neonates as controls. After history taking and clinical examination, complete blood count, C-reactive protein and 25-OH vitamin D serum levels (neonatal and maternal) were measured for all neonates. The mean gestational age for neonates with sepsis was (37.5 ± 0.98 for full term and 34.1 ± 1.26 for preterm neonates). Neonatal and maternal 25-OH vitamin D serum levels were significantly lower in patients (6.4 ± 1.8 and 24.6 ± 2.2 nmol/L) than controls (42.5 ± 20.7 and 50.4 ± 21.4 nmol/L). Significant negative correlations between neonatal and maternal 25-OH vitamin D serum levels and all sepsis markers and significant positive correlations between neonatal and maternal 25-OH vitamin D levels were present. At cut-off values <20 nmol/L for neonatal and <42 nmol/L for maternal 25-OH vitamin D for detection of neonatal sepsis, the sensitivity, specificity, positive predicted value (PPV) and negative predicted value (NPV) were 84%, 79%, 94.7% and 82.3% for neonatal and 82%, 77%, 91.4% and 80.6% for maternal 25-OH vitamin D, respectively. Positive correlations between neonatal and maternal 25-OH Vitamin D serum levels are present and they are negatively correlated with all sepsis markers. They can be sensitive early predictors for early onset sepsis in neonates.

Nonconventional Markers of Sepsis

Sepsis still remains a challenging healthcare problem with high mortality rate. To improve outcome, early diagnosis and monitoring of sepsis is of utmost importance. In this process objective laboratory parameters are the most helpful. Procalcitonin and C-reactive protein are the most commonly used and recommended markers of sepsis however, more than 200 sepsis biomarkers have already been published. This mini review focuses on nonconventional novel possibilities for the recognition of sepsis severity. Presepsin, actin and actin scavenger proteins (gelsolin and Gc-globulin) and orosomucoid are discussed. Besides serum parameters, the urinary levels of these markers are also elaborated, since urinary biomarkers of sepsis provide new diagnostic implications and are helpful for monitoring both the kidney function and the septic process. Increasing serum actin levels and decreasing levels of actin binding proteins seem to be associated with sepsis severity and outcome. Actin can be detected in the urine samples of septic patients as well, and strongly elevated levels of it were found in sepsis-related acute kidney injury. Both serum and urinary orosomucoid might be able to indicate sepsis, however urinary orosomucoid is a more sensitive inflammatory marker. Novel laboratory tests can provide rapid help for clinical decision making because the key point in successful treatment lies in the early diagnosis of sepsis.

Impact of high-dose vitamin D3 on plasma free 25-hydroxyvitamin D concentrations and antimicrobial peptides in critically ill mechanically ventilated adults

OBJECTIVES

High-dose vitamin D₃ increases plasma total 25-hydroxyvitamin D [25(OH)D] in critically ill, ventilated patients; however, to our knowledge, the effect on plasma levels of free (nonprotein-bound) 25(OH)D has not been investigated in critical illness. Moreover, the relationship of free 25(OH)D and the regulation of endogenous antimicrobial peptides (AMPs) remains unknown. The aims of this study were to determine in critically ill adults with respiratory failure the effect of previous high-dose regimens of vitamin D₃ on free 25(OH)D concentrations, the relationship of free 25(OH)D with circulating cathelicidin (LL-37) and human beta-defensin-2 (hBD-2), and the associations between plasma levels of free 25(OH)D and these AMPs to alveolar macrophage phagocytosis function.

METHODS

In a double blind, randomized controlled trial, critically ill ventilator-dependent adults (N = 30) received enteral vitamin D₃ (250,000 or 500,000 IU total over 5 d) or placebo. Plasma was obtained serially for concentrations of free 25(OH)D, LL-37, hBD-2, and expression of peripheral blood mononuclear cell human cationic antimicrobial protein (hCAP18) mRNA. Total 25(OH)D and LL-37 concentrations and alveolar macrophage phagocytosis were determined in bronchoalveolar lavage fluid.

RESULTS

Plasma concentrations of free 25(OH)D over time were correlated with total 25(OH)D levels (r= 0.82; P < 0.001). The increase in free 25(OH)D was greater with the 500 000 IU vitamin D₃ dose than with the lower dose. The percent change in mRNA expression of hCAP18 was positively associated with percent change in free 25(OH)D at days 7 and 14 (ρ = 0.48; P = 0.04 and ρ = 0.59; P = 0.03, respectively). Additionally, plasma LL-37 levels correlated with the percentage of alveolar macrophages exhibiting phagocytosis (ρ = 0.51; P = 0.04).

CONCLUSIONS

The present study found a dose-related increase in plasma free-25(OH)D levels, which was associated with increasing circulating mRNA expression of hCAP18 over time. There were no correlations between changes in total and free 25(OH)D against plasma LL-37 and hBD-2 concentrations. Larger studies appear warranted to determine the impact of high-dose vitamin D₃ administration on endogenous AMPs.

Outcomes of Vitamin D Supplementation in Adults Who are Deficient and Critically Ill: A Review of the Literature

Vitamin D deficiency is known to be common in the general population and has been linked to all-cause mortality. The classically recognized role of vitamin D is its involvement in calcium and phosphorous homeostasis and bone health. Recent evidence suggests that vitamin D may also play a role in other nonskeletal processes, such as anti-proliferation, immunity, regulation of hormone section, and muscle strength. An extensive literature review of vitamin D and critical illness from 2000 to 2015 (PubMed and CINAL) produced multiple observational studies revealing a high prevalence of vitamin D deficiency in intensive care patients. Many of these studies have indicated that there is an association between vitamin D deficiency and clinical outcomes such as mortality, sepsis, duration of mechanical ventilation, and length of stay. This review article provides an overview of vitamin D physiology in adults, a summary of observational studies on vitamin D deficiency in critical illness, and an examination of the few clinical trials on vitamin D supplementation in intensive care patients.

Endogenous antimicrobial factors in the treatment of infectious diseases

Nowadays, a number of antibiotic-resistant bacteria strains is increasing. It is a serious clinical problem and poses a threat to the effectiveness of conventional antibiotic therapy. Thus, scientists are constantly seeking new alternatives for treatment of infectious diseases. There are some natural endogenous factors, which possess antimicrobial activities against a large number of microorganisms, including both Gram-positive and Gram-negative bacteria, viruses and fungi. These factors are present in all eukaryotic organisms and constitute an essential element of their immune system. A large number of in vitro and in vivo models have been used to show the activity of antimicrobial factors, and only few studies have been conducted on people. Results indicate that administration of these molecules is therapeutically beneficial. This review summarizes knowledge of selected endogenous antimicrobial agents, such as cathelicidins, defensins, histatins, lysozyme and lactoferrin. We also discuss potential uses of these factors in the treatment of infectious diseases.

25(OH)D and 1,25(OH)D vitamin D fails to predict sepsis and mortality in a prospective cohort study

The clinical role of vitamin D in sepsis and mortality prediction is controversially discussed. Therefore, we conducted a prospective cohort study on standard care wards, including 461 patients with suspected sepsis fulfilling two or more SIRS criteria. On the first and third day after onset of SIRS symptoms levels of 25(OH)D, 1,25(OH)D and sepsis biomarkers were analysed for their predictive capacity for identifying infection, bacteraemia and an elevated mortality risk. Additionally, several SNPs associated with vitamin D metabolism were evaluated. Bacteraemic patients (28.5%) presented with significantly lower 1,25(OH)D levels than SIRS patients without bacteraemia on the first and third day, while 25(OH)D did not show a predictive capacity. No significant differences of either 1,25(OH)D or 25(OH)D levels were found between SIRS patients with and without infections or between survivors and non-survivors. Sepsis biomarkers, including procalcitonin and CRP, showed a significantly higher discriminatory capacity for these classification tasks. The vitamin D metabolism-related SNPs analysed did not indicate any association with our outcome measures. In conclusion, 1,25(OH)D but not 25(OH)D showed a minor discriminatory value for the prediction of bacteraemia that was inferior to CRP and PCT but both failed to predict sepsis and mortality in a prospective cohort of SIRS patients.

Correlation of Serum Vitamin D Level with Mortality in Patients with Sepsis

Background:

Sepsis is the leading cause of mortality in the critically ill. Recently, it has been found in many studies that many trace elements and nutrients do have an effect on human body and if supplemented can improve the prognosis in patients with sepsis.

Aim and Objectives:

Primary objective: Whether low Vitamin D is associated with mortality. Secondary objective: To find out association of low Vitamin D levels and morbidity in terms of length of hospital and Intensive Care Unit (ICU) stay.

Subjects and Methods:

Following ethical approval, consent will be sought from either the patient or assent from a near relative. Successive patients admitted to the medical emergency and ICU at tertiary care health center who fulfill the following criteria for sepsis, within a 24 h time window, were included in the study.

Results:

Among 88 patients evaluated in our study 15 patients (18.2%) were found to have adequate Vitamin D levels and seven patients (8%) were found insufficient and rest 52 patients (73.9%) were found deficient in Vitamin D. Age of the patients ranged between 18 and 82 years with mean (±standard deviation) 45.02 ± 17.69 years. Mean Vitamin D level was found significantly higher among patients with positive outcome than those with unfavorable outcome (expiry) (t = 2.075, P = 0.04). On comparison of the length of hospital stay (morbidity) with Vitamin D levels, we found statistically significant inverse relation between Vitamin D levels and length of hospital stay.

Conclusion:

Vitamin D deficiency leads to increased risk of mortality in the critically ill along with prolonged hospital stay.

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.

[Vitamin D deficiency and morbimortality in critically ill paediatric patients]

OBJECTIVES

To determine the prevalence and risks factors of vitamin D deficiency, as well as its relationship with morbidity and mortality in a PICU.

MATERIAL AND METHODS

An observational prospective study in a tertiary children's University Hospital PICU conducted in two phases: i: cohorts study, and ii: prevalence study. The study included 340 critically ill children with ages comprising 6 months to 16 years old.

EXCLUSION CRITERIA

Chronic kidney disease, known parathyroid disorders, and vitamin D supplementation. Total 25-hydroxyvitamin D [25(OH)D] was measured in the first 48hours of admission to a PICU. Parathormone, calcium, phosphate, blood gases, blood count, C-reactive protein, and procalcitonin were also analysed. A record was also made of demographic features, characteristics of the episode, and complications during the PICU stay.

RESULTS

The overall prevalence rate of vitamin D deficiency was 43.8%, with a mean of 22.28 (95% CI 21.15-23.41) ng/ml. Patients with vitamin D deficiency were older (61 vs 47 months, P=.039), had parents with a higher level of academic studies (36.5% vs 20%, P=.016), were admitted more often in winter and spring, had a higher PRISM-III (6.8 vs 5.1, P=.037), a longer PICU stay (3 vs 2 days, P=.001), and higher morbidity (61.1% vs 30.4%, P<001) than the patients with sufficient levels of 25(OH)D. Patients who died had lower levels of 25(OH)D (14±8.81ng/ml versus 22.53±10.53ng/ml, P=.012). Adjusted OR for morbidity was 5.44 (95%CI; 2.5-11.6).

CONCLUSIONS

Vitamin D deficiency is frequent in critically ill children, and it is related to both morbidity and mortality, although it remains unclear whether it is a causal relationship or it is simply a marker of severity in different clinical situations.

Fibroblast Growth Factor 23 and the Risk of Infection-Related Hospitalization in Older Adults

Within monocytes, 1,25-dihydroxyvitamin D [1,25(OH)₂D] is important for production of cathelicidins, which in turn, are critical for antibacterial action. Fibroblast growth factor 23 (FGF23) decreases 1,25(OH)₂D production and thus, could increase infection risk. We examined this possibility in 3141 community-dwelling adults ages ≥65 years old at baseline in the Cardiovascular Health Study using Cox proportional hazards models to examine the association between FGF23 concentrations and first infection-related hospitalizations and determine whether associations differed by the presence of CKD (eGFR<60 ml/min per 1.73 m² [n=832] or urine albumin-to-creatinine ratio >30 mg/g [n=577]). Mean±SD age of participants was 78±5 years old, 60% of participants were women, and the median plasma FGF23 concentration was 70 (interquartile range, 53-99) relative units per milliliter. In fully adjusted models, higher FGF23 concentrations associated with higher risk of first infection-related hospitalization (hazard ratio [HR], 1.11; 95% confidence interval [95% CI], 1.03 to 1.20 per doubling of FGF23) during a median follow-up of 8.6 years. In participants with or without CKD (defined by eGFR), FGF23 concentration associated with first infection-related hospitalization with HRs of 1.24 (95% CI, 1.08 to 1.42) and 1.06 (95% CI, 0.97 to 1.17) per doubling of FGF23, respectively (P=0.13 for interaction). Associations did not differ between groups when stratified by urine albumin-to-creatinine ratio. In sensitivity analyses, the addition of serum calcium, phosphorus, 25-hydroxyvitamin D, intact parathyroid hormone, and 24,25-dihydroxyvitamin D did not meaningfully change the estimates. In conclusion, in community-dwelling older adults, higher plasma FGF23 concentrations independently associated with the risk of first infection-related hospitalization.

Burden and Outcome of Vitamin D Deficiency Among Critically Ill Patients: A Prospective Study

BACKGROUND

Vitamin D deficiency is a prevalent condition among critically ill patients. Information about the relationship between vitamin D levels and outcomes in the intensive care unit (ICU) is sparse.

PURPOSE

To evaluate vitamin D status among critically ill patients and its relevance to severity of illness, ICU stay period, and mortality.

METHODS

This prospective multicenter study was conducted in the ICUs of Fayoum, Cairo, Alazhar, and Ain Shams university hospitals. All patients were subjected to interview questionnaire, laboratory investigation, vitamin D level assessment, and severity of illness evaluation using the Acute Physiologic Assessment and Chronic Health Evaluation II (APACHE II) score.

RESULTS

In total, 250 patients were included in the study. The median age was 62 (40-73) years, and most patients were male (52%). The median serum level of vitamin D was 19 (7-40.6). Vitamin D was deficient in 197 patients (78.8%) on admission. While we grouped the ICU patients as vitamin D deficient, insufficient, and sufficient, vitamin D-deficient patients had more severe diseases (mean APACHE II score, 44 ± 15; P = .014). Prolonged ICU stay was observed among the deficient group but with no significant association. The overall mortality rate was 6.8%; of these, 70.5% were vitamin D-deficient patients. However, logistic regression analysis demonstrated that vitamin D deficiency was not an independent risk factor for mortality.

CONCLUSION

Vitamin D insufficiency is common in critically ill patients (69%); it is associated with more severity of illness, but it is not an independent risk factor for longer ICU stay or mortality.

Vitamin D deficiency in critically ill patients with traumatic injuries

Background

Vitamin D depletion has been associated with increased rate of infections, lengthened hospital stay, and worsened mortality for critically ill patients. The purpose of this study was to evaluate the prevalence and variables associated with vitamin D deficiency in critically ill patients with severe traumatic injuries.

Methods

Critically ill adult patients admitted to the trauma intensive care unit (ICU) between June 2013 and June 2014, referred to the nutrition support service for enteral or parenteral nutrition, and had a serum 25-hydroxyvitamin D (25-OH vitamin D) concentration determination were retrospectively evaluated. Patients were stratified as vitamin D sufficient, insufficient, deficient, or severely deficient based on a 25-OH vitamin D concentration of 30–80, 20–29.9, 13.1–19.9, and ≤13 ng/mL, respectively.

Results

One hundred and twenty-one patients out of 158 (76 %) patients were vitamin D deficient or severely deficient. Thirty-one patients (20 %) were insufficient and 6 (4 %) had a normal 25-OH vitamin D concentration. 25-OH vitamin D was determined 7.5 ± 5.1 days after ICU admission. African-Americans had a greater proportion of patients with deficiency or severe deficiency compared to other races (91 versus 64 %, P = 0.02). Penetrating gunshot or knife stab injury, African-American race, and obesity (elevated body mass index) were significantly associated with vitamin D deficiency or severe deficiency: OR 9.23 (1.13, 75.40), 4.0 (1.4, 11.58), and 1.12 (1.03, 1.23), P < 0.05, respectively.

Conclusions

The majority of critically ill patients with traumatic injuries exhibit vitamin D deficiency or severe deficiency. Penetrating injuries, African-American race, and obesity are significant risk factors for deficiency. Severity of injury, extent of inflammation (elevated C-reactive protein concentration), or hospital admission during the winter season did not significantly influence the prevalence of vitamin D deficiency.

Severe vitamin D deficiency is common in critically ill patients at a high northern latitude

BACKGROUND

Critically ill patients at southern latitudes have been shown to have low vitamin D levels that were associated with prolonged hospital stay. To our knowledge no studies have been conducted on vitamin D status amongst critically ill patients at high northern latitudes. Despite the Icelandic population traditionally taking vitamin D supplements, we hypothesized that the majority of critically ill patients in Reykjavik, Iceland have low vitamin D levels.

METHODS

This was a prospective observational study on 122 patients admitted to Landspitali University Hospital intensive care unit. Serum vitamin D (25(OH)D) was measured in all patients on two occasions (first and second day). The prevalence of vitamin D deficiency and its effect on hospital stay was calculated.

RESULTS

Only 9% of patients had vitamin D levels recommended for good health (>75 nmol/l) and 69% were deficient (25(OH)D < 50 nmol/l). The average difference between the first and second vitamin D samples was 2.8 nmol/l. Forty-three percentage of the severely vitamin D deficient stayed in the ICU for more than 4 days compared to 19% of patients with better status (P = 0.196).

DISCUSSION

Vitamin D deficiency is very common in critically ill patients at high northern latitudes and patients with severely deficient vitamin D levels had trend towards longer intensive care unit stay. Furthermore, 43% of the patients had vitamin D levels under 25 nmol/l that is associated with osteomalacia. It appears that a single vitamin D measurement gives a reasonable clue about the vitamin D status in critically ill patients.

Genotyping of vitamin D receptor gene polymorphisms using mismatched amplification mutation assay in neonatal sepsis patients of Odisha, eastern India

Vitamin D has potent antimicrobial and anti-inflammatory properties. Vitamin D deficiency has been shown to be associated with the risk of vulnerability to different infectious diseases, such as neonatal sepsis. Polymorphisms in vitamin D receptor (VDR) gene can influence the expression of vitamin D in individuals. Hence, it is essential to study the vitamin D status and VDR gene polymorphisms for assessing neonatal sepsis risk. In this study, we assessed the serum 25(OH)D, the main circulating form of vitamin D and VDR polymorphism on 120 subjects in a case-control approach, recruiting 60 subjects in each category. We genotyped Fok1, Bsm1, Apa1 and Taq1 gene polymorphisms in VDR by developing a unique mismatch amplification mutation assay (MAMA) and studied their association in both populations. VDR-MAMA primers were designed by addition of dual mismatches (DM) near the 3' end and were selected based on high ΔCt values in comparison to single mismatch (SM) primers using SYBR-Green RT-PCR, which were eventually used for VDR genotyping. Genotyping was also performed using PCR-RFLP for further confirmation. Serum 25(OH)D ELISA revealed that cases were vitamin D insufficient (Median=12.16ng/ml, 95% CI: 3.84-22.22) and controls were vitamin D sufficient (Median=30.22ng/ml, 95% CI: 20.08-46.78; p<0.0001) respectively, which indicated that vitamin D insufficiency was mostly prevalent in cases. We found no evidence of association between genotypes of the Apa1 polymorphism and neonatal sepsis or 25(OH)D serum levels. The distributions of the Fok1, Bsm1, and Taq1 genotypes were not consistent with Hardy-Weinberg equilibrium in the control group. Future studies in larger populations are required to establish whether the VDR polymorphisms can be potentially used as genetic markers for early screening towards predisposition to neonatal sepsis risk. In this study, we describe a simple, inexpensive and rapid screening of VDR gene polymorphisms using VDR MAMA-PCR, which can be used in both clinical and research laboratories.

Patient Optimization-Strategies That Work: Malnutrition

BACKGROUND

Patient optimization is receiving increasing attention as outcomes monitoring and bundled payments have been introduced in joint arthroplasty. Optimization of nutrition is an important aspect of perioperative management.

METHODS

This manuscript is a review of previously published material related to nutrition and the impact of malnutrition on surgical outcomes, with guidance for surgeons preparing patients for elective joint arthroplasty.

RESULTS

Patients with optimized nutritional parameters have fewer complications, especially related to wound healing and infection.

CONCLUSION

Nutritional assessment and optimization should be a part of the perioperative management of patients undergoing lower extremity arthroplasty.

Longitudinal increase in vitamin D binding protein levels after initiation of tenofovir/lamivudine/efavirenz among individuals with HIV

OBJECTIVE

To examine longitudinal change in vitamin D binding protein (DBP) levels during the first year after initiation of tenofovir disoproxil fumarate (TDF)/lamivudine/efavirenz and compare these findings with concurrent changes in markers of skeletal metabolism.

DESIGN

Secondary analysis of plasma samples collected from an ongoing multicenter clinical trial.

METHODS

Plasma samples collected at 0, 24, and 48 weeks after initiation of TDF + lamivudine + efavirenz from 134 adult participants enrolled in a multicenter randomized trial were analyzed. Data regarding sociodemographic and clinical characteristics were obtained as part of the parent study. Laboratory analyses included plasma DBP, intact parathyroid hormone, total 25-hydroxy vitamin D, phosphorus, the bone resorption marker collagen type 1 cross-linked C-telopeptide, and the bone formation marker total procollagen type 1 N-terminal propeptide. Repeated measures analysis of variance was used to measure changes in biomarkers over time.

RESULTS

Our sample included 108 men and 26 women (mean age 33.6 ± 9.6 years). Median levels of DBP increased significantly from baseline to 48 weeks [154 (91.8-257.4) versus 198.3 (119.6-351.9) μg/ml, P < 0.001]. A concurrent rise in intact parathyroid hormone levels was observed over the same period [32.3 (24.4-40.9) versus 45.2 (35.1-60.4) pg/ml, P < 0.001]; however, 25-hydroxy vitamin D and phosphorus levels remained stable. Bone resorption and formation markers rapidly increased from 0 to 24 weeks, followed by a slight decline or plateau, but remained significantly elevated at 48 weeks (P < 0.001).

CONCLUSION

Our study provides longitudinal data supporting a potential role for DBP in bone loss associated with TDF-based therapy. Further research to elucidate the mechanistic pathways and clinical impact of these findings is warranted.

Crosstalk between Vitamin D Metabolism, VDR Signalling, and Innate Immunity

The primary function of vitamin D is to regulate calcium homeostasis, which is essential for bone formation and resorption. Although diet is a source of vitamin D, most foods are naturally lacking vitamin D. Vitamin D is also manufactured in the skin through a photolysis process, leading to a process called the “sunshine vitamin.” The active form of vitamin D, 1,25-dihydroxyvitamin D (calcitriol), is biosynthesised in the kidney through the hydroxylation of 25-hydroxycholecalciferol by the CYP27B1 enzyme. It has been found that several immune cells express the vitamin D receptor (VDR) and CYP27B1; of the latter, synthesis is determined by several immune-specific signals. The realisation that vitamin D employs several molecular mechanisms to regulate innate immune responses is more recent. Furthermore, evidence collected from intervention studies indicates that vitamin D supplements may boost clinical responses to infections. This review considers the current knowledge of how immune signals regulate vitamin D metabolism and how innate immune system function is modulated by ligand-bound VDR.

Biomarkers of systemic inflammation in farmers with musculoskeletal disorders; a plasma proteomic study

Background

Farmers have an increased risk for musculoskeletal disorders (MSD) such as osteoarthritis of the hip, low back pain, and neck and upper limb complaints. The underlying mechanisms are not fully understood. Work-related exposures and inflammatory responses might be involved. Our objective was to identify plasma proteins that differentiated farmers with MSD from rural referents.

Methods

Plasma samples from 13 farmers with MSD and rural referents were included in the investigation. Gel based proteomics was used for protein analysis and proteins that differed significantly between the groups were identified by mass spectrometry.

Results

In total, 15 proteins differed significantly between the groups. The levels of leucine-rich alpha-2-glycoprotein, haptoglobin, complement factor B, serotransferrin, one isoform of kininogen, one isoform of alpha-1-antitrypsin, and two isoforms of hemopexin were higher in farmers with MSD than in referents. On the other hand, the levels of alpha-2-HS-glycoprotein, alpha-1B-glycoprotein, vitamin D- binding protein, apolipoprotein A1, antithrombin, one isoform of kininogen, and one isoform of alpha-1-antitrypsin were lower in farmers than in referents. Many of the identified proteins are known to be involved in inflammation.

Conclusions

Farmers with MSD had altered plasma levels of protein biomarkers compared to the referents, indicating that farmers with MSD may be subject to a more systemic inflammation. It is possible that the identified differences of proteins may give clues to the biochemical changes occurring during the development and progression of MSD in farmers, and that one or several of these protein biomarkers might eventually be used to identify and prevent work-related MSD.

Electronic supplementary material

The online version of this article (doi:10.1186/s12891-016-1059-y) contains supplementary material, which is available to authorized users.

Circulating Cathelicidin Concentrations in a Cohort of Healthy Children: Influence of Age, Body Composition, Gender and Vitamin D Status

Cathelicidin is an antimicrobial peptide whose circulating levels are related to vitamin D status in adults. This study sought to determine if circulating cathelicidin concentrations in healthy children are related to the age of the child, body composition and vitamin D status at birth and at the time of the study visit. Blood samples were obtained during yearly visits from 133 children, ages 2–7, whose mothers had participated in a pregnancy vitamin D supplementation RCT. Radioimmunoassay and ELISA were performed to analyze 25(OH)D and cathelicidin, respectively. Statistical analyses compared cathelicidin concentrations with concentrations of 25(OH)D at various time points (maternal levels throughout pregnancy, at birth, and child’s current level); and with race/ethnicity, age, gender, BMI, percent fat, and frequency of infections using Student’s t-test, χ², Wilcoxon ranked-sum analysis, and multivariate regression. The cohort’s median cathelicidin concentration was 28.1 ng/mL (range: 5.6–3368.6) and did not correlate with 25(OH)D, but was positively correlated with advancing age (ρ = 0.236 & p = 0.005, respectively). Forty patients evaluated at two visits showed an increase of 24.0 ng/mL in cathelicidin from the first visit to the next (p<0.0001). Increased age and male gender were correlated with increased cathelicidin when controlling for race/ethnicity, percent fat, and child’s current 25(OH)D concentration (p = 0.028 & p = 0.047, respectively). This study demonstrated that as children age, the concentration of cathelicidin increases. Furthermore, male gender was significantly associated with increased cathelicidin concentrations. The lack of association between vitamin D status and cathelicidin in this study may be due to the narrow range in observed 25(OH)D values and warrants additional studies for further observation.

High Dose Vitamin D Administration in Ventilated Intensive Care Unit Patients: A Pilot Double Blind Randomized Controlled Trial

•

First double blind RCT of vitamin D therapy in mechanically ventilated patients.

•

Treatment with placebo, 250,000 IU or 500,000 IU enteral vitamin D3 was well tolerated.

•

Significant increase in plasma 25(OH)D from baseline to day 7.

•

Significant decrease in hospital length of stay for vitamin D3 treated subjects.

•

No change in plasma LL-37 according to treatment group.

Background

There is a high prevalence of vitamin D deficiency in the critically ill patient population. Several intensive care unit studies have demonstrated an association between vitamin D deficiency [25-hydroxyvitamin D (25(OH)D) < 20 ng/mL] and increased hospital length of stay (LOS), readmission rate, sepsis and mortality.

Material and Methods

Pilot, double blind randomized control trial conducted on mechanically ventilated adult ICU patients. Subjects were administered either placebo, 50,000 IU vitamin D₃ or 100,000 IU vitamin D₃ daily for 5 consecutive days enterally (total vitamin D₃ dose = 250,000 IU or 500,000 IU, respectively). The primary outcome was plasma 25(OH)D concentration 7 days after oral administration of study drug. Secondary outcomes were plasma levels of the antimicrobial peptide cathelicidin (LL37), hospital LOS, SOFA score, duration of mechanical ventilation, hospital mortality, mortality at 12 weeks, and hospital acquired infection.

Results

A total of 31 subjects were enrolled with 13 (43%) being vitamin D deficient at entry (25(OH)D levels < 20 ng/mL). The 250,000 IU and 500,000 IU vitamin D₃ regimens each resulted in a significant increase in mean plasma 25(OH)D concentrations from baseline to day 7; values rose to 45.7 ± 19.6 ng/mL and 55.2 ± 14.4 ng/mL, respectively, compared to essentially no change in the placebo group (21 ± 11.2 ng/mL), p < 0.001. There was a significant decrease in hospital length of stay over time in the 250,000 IU and the 500,000 IU vitamin D₃ group, compared to the placebo group (25 ± 14 and 18 ± 11 days compared to 36 ± 19 days, respectively; p = 0.03). There was no statically significant change in plasma LL-37 concentrations or other clinical outcomes by group over time.

Conclusions

In this pilot study, high-dose vitamin D3 safely increased plasma 25(OH)D concentrations into the sufficient range and was associated with decreased hospital length of stay without altering other clinical outcomes.

Vitamin D Deficiency in Pediatric Critical Care

Vitamin D deficiency (VDD) is a well-established cause of pediatric bone and muscle disease. In addition, a role has been recognized for vitamin D in the health and stress response of other organs, including the cardiovascular, immune, and respiratory systems. As these organs are central to the development of and recovery from critical illness, VDD has been hypothesized to be a modifiable risk factor for ICU outcome. Over the past 5 years, a growing number of adult and pediatric critical care studies have investigated the prevalence of VDD and its association with illness severity and outcome. The adult studies have recently been synthesized in systematic reviews, with results that convincingly suggest the need for trials to determine whether optimization of vitamin D status improves outcome. In contrast, the pediatric ICU and related literature has not been similarly synthesized. The goal of this review is to describe vitamin D metabolism, known biological mechanisms, potential role in pathophysiology, and summarize the available pediatric intensive care unit (PICU) studies reporting on prevalence of VDD deficiency and its association with outcome. The problems with currently approved supplementation approaches and alternative strategies are discussed, including evidence from available RCTs in adult ICU. Altogether the results suggest that critically ill children are at risk for VDD, and that VDD appears to be associated with a worse clinical course. Clinical trials evaluating novel approaches to testing for and supplementing vitamin D require exploration.

The differential effects of 1,25-dihydroxyvitamin D3 on Salmonella-induced interleukin-8 and human beta-defensin-2 in intestinal epithelial cells

Salmonellosis or Salmonella, one of the most common food-borne diseases, remains a major public health problem worldwide. Intestinal epithelial cells (IECs) play an essential role in the mucosal innate immunity of the host to defend against the invasion of Salmonella by interleukin (IL)-8 and human β-defensin-2 (hBD-2). Accumulated research has unravelled important roles of vitamin D in the regulation of innate immunity. Therefore, we investigated the effects of 1,25-dihydroxyvitamin D3 (1,25D3) on Salmonella-induced innate immunity in IECs. We demonstrate that pretreatment of 1,25D3 results in suppression of Salmonella-induced IL-8 but enhancement of hBD-2, either protein secretion and mRNA expression, in IECs. Furthermore, 1,25D3 enhanced Salmonella-induced membranous recruitment of nucleotide oligomerization domain (NOD2) and its mRNA expression and activation of protein kinase B (Akt), a downstream effector of phosphoinositide 3-kinase (PI3K). Inhibition of the PI3K/Akt signal counteracted the suppressive effect of 1,25D3 on Salmonella-induced IL-8 expression, while knock-down of NOD2 by siRNA diminished the enhanced hBD-2 expression. These data suggest differential regulation of 1,25D3 on Salmonella-induced IL-8 and hBD-2 expression in IECs via PI3K/Akt signal and NOD2 protein expression, respectively. Active vitamin D-enhanced anti-microbial peptide in Salmonella-infected IECs protected the host against infection, while modulation of proinflammatory responses by active vitamin D prevented the host from the detrimental effects of overwhelming inflammation. Thus, active vitamin D-induced innate immunity in IECs enhances the host's protective mechanism, which may provide an alternative therapy for invasive Salmonella infection.

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.

More than metabolic: Considering the broader paleoepidemiological impact of vitamin D deficiency in bioarchaeology

Vitamin D deficiency has traditionally been viewed as a metabolic bone disease by bioarchaeologists and considered primarily in terms of the development of specific musculoskeletal changes used for diagnosis in paleopathological research. These skeletal manifestations are usually interpreted as representing general ill-health. Clinical research shows that vitamin D is also integral to a number of extra-skeletal physiological processes including immunoregulation, blood pressure homeostasis, cell division, and programmed cell death. Vitamin D deficiency and sub-clinical insufficiency are thought to be risk factors for infectious and autoimmune diseases, as well as certain cancers and cardiovascular diseases. Epidemiological work indicates that the skeletal manifestations of vitamin D deficiency represent the extreme end of a spectrum of morbidity associated with negative health outcomes, including increased risk for secondary tuberculosis. This article provides a review of clinical research on the extra-skeletal roles of vitamin D and the pathological consequences of poor vitamin D status. Additionally, it presents an interpretive model for bioarchaeological analyses of rickets and osteomalacia for consideration of the whole-body impact of poor vitamin D nutriture and possible comorbidities that may have affected the wider population. Am J Phys Anthropol 160:183-196, 2016. © 2016 Wiley Periodicals, Inc.

[Vitamin D level in children with bloodstream infection]

OBJECTIVE

To investigate the difference in serum 25(OH)D level between children with bloodstream infection and healthy children.

METHODS

A case-control study was conducted among 60 children with bloodstream infection who were hospitalized between January 2010 and December 2013 and had positive results of two blood cultures. Meanwhile, 60 aged-matched healthy children who underwent physical examination during the same period of time were enrolled as the healthy control group. Chemiluminescence was applied to measure the serum 25(OH)D level, and the constituent ratios of children with different serum 25(OH)D levels were compared between the two groups.

RESULTS

The bloodstream infection group had a significantly lower serum 25(OH)D level than the healthy control group (P<0.01). Compared with the healthy control group, the bloodstream group had significantly lower constituent ratios of children with normal Vitamin D level (8% vs 35%) or vitamin D insufficiency (22% vs 43%) (P<0.05). Compared with the healthy control group, the bloodstream group had significantly higher constituent ratios of children with vitamin D deficiency (42% vs 13%) or severely vitamin D deficiency (28% vs 8%) (P<0.01).

CONCLUSIONS

Vitamin D insufficiency prevails among children, and children with bloodstream infection have a significantly lower serum 25(OH)D level than healthy children.

Free 25-Hydroxyvitamin D Concentrations in Cystic Fibrosis

BACKGROUND

Vitamin D deficiency is common in cystic fibrosis (CF), but there is no previous data on free 25-hydroxyvitamin D (25[OH]D) in CF or in relation to healthy individuals.

METHODS

We assessed total serum 25(OH)D concentration by chemiluminescence and serum free 25(OH)D concentration by both direct measurement (ELISA) and calculation, using serum albumin and vitamin D binding protein (VDBP) levels in 80 subjects (28 healthy adults, 25 clinically stable adults and children with CF and 27 adults experiencing a CF exacerbation).

RESULTS

Serum albumin and VDBP concentrations were lower in CF compared with healthy controls. Total serum 25(OH)D concentrations were positively correlated with both calculated and measured free 25(OH)D (P < 0.001 for both). Calculated and directly measured serum free 25(OH)D levels were positively correlated (P < 0.001).

CONCLUSIONS

Serum levels of directly measured free 25(OH)D positively correlated with total 25(OH)D, suggesting that achieving sufficient total serum 25(OH)D may result in adequate free 25(OH)D levels in CF.

A Randomized Study of a Single Dose of Intramuscular Cholecalciferol in Critically Ill Adults

OBJECTIVES

To determine the effect of two doses of intramuscular cholecalciferol on serial serum 25-hydroxy-vitamin-D levels and on pharmacodynamics endpoints: calcium, phosphate, parathyroid hormone, C-reactive protein, interleukin-6, and cathelicidin in critically ill adults.

DESIGN

Prospective randomized interventional study.

SETTING

Tertiary, academic adult ICU.

PATIENTS

Fifty critically ill adults with the systemic inflammatory response syndrome.

INTERVENTION

Patients were randomly allocated to receive a single intramuscular dose of either 150,000 IU (0.15 mU) or 300,000 IU (0.3 mU) cholecalciferol.

MEASUREMENTS AND MAIN RESULTS

Pharmacokinetic, pharmacodynamic parameters, and outcome measures were collected over a 14-day period or until ICU discharge, whichever was earlier. Prior to randomization, 28 of 50 patients (56%) were classified as vitamin D deficient. By day 7 after randomization, 15 of 23 (65%) and 14 of 21 patients (67%) normalized vitamin D levels with 0.15 and 0.3 mU, respectively (p=0.01) and by day 14, 8 of 10 (80%) and 10 of 12 patients (83%) (p=0.004), respectively. Secondary hyperparathyroidism was manifested in 28% of patients at baseline. Parathyroid hormone levels decreased over the study period with patients achieving vitamin D sufficiency at day 7 having significantly lower parathyroid hormone levels (p<0.01). Inflammatory markers (C-reactive protein and interleukin-6) fell significantly over the study period. Greater increments in 25-hydroxy-vitamin-D were significantly associated with greater increments in cathelicidin at days 1 and 3 (p=0.04 and 0.004, respectively). Although in-hospital mortality rate did not differ between the groups, patients who did not mount a parathyroid hormone response to vitamin D deficiency had a higher mortality (35% vs 12%; p=0.05). No significant adverse effects were observed.

CONCLUSIONS

A single dose of either dose of intramuscular cholecalciferol corrected vitamin D deficiency in the majority of critically ill patients. Greater vitamin D increments were associated with early greater cathelicidin increases, suggesting a possible mechanism of vitamin D supplementation in inducing bactericidal pleiotropic effects.

The role of geographical ecological studies in identifying diseases linked to UVB exposure and/or vitamin D

Using a variety of approaches, researchers have studied the health effects of solar ultraviolet (UV) radiation exposure and vitamin D. This review compares the contributions from geographical ecological studies with those of observational studies and clinical trials. Health outcomes discussed were based on the author's knowledge and include anaphylaxis/food allergy, atopic dermatitis and eczema, attention deficit hyperactivity disorder, autism, back pain, cancer, dental caries, diabetes mellitus type 1, hypertension, inflammatory bowel disease, lupus, mononucleosis, multiple sclerosis, Parkinson disease, pneumonia, rheumatoid arthritis, and sepsis. Important interactions have taken place between study types; sometimes ecological studies were the first to report an inverse correlation between solar UVB doses and health outcomes such as for cancer, leading to both observational studies and clinical trials. In other cases, ecological studies added to the knowledge base. Many ecological studies include other important risk-modifying factors, thereby minimizing the chance of reporting the wrong link. Laboratory studies of mechanisms generally support the role of vitamin D in the outcomes discussed. Indications exist that for some outcomes, UVB effects may be independent of vitamin D. This paper discusses the concept of the ecological fallacy, noting that it applies to all epidemiological studies.

Clinical and microbiological outcome in septic patients with extremely low 25-hydroxyvitamin D levels at initiation of critical care

A relationship between vitamin D status and mortality in patients in intensive care units (ICU) has been documented. The present study aims to describe the clinical profile and sepsis-related outcome of critically ill septic patients with extremely low (<7 ng/mL) vitamin D levels at ICU admission. We conducted an observational study in the ICU of a teaching hospital including all patients admitted with severe sepsis/septic shock and undergoing 25-hydroxyvitamin D (25(OH)D) testing within the first 24 hours from admission. We studied 107 patients over 12 months. At ICU admission vitamin D deficiency (≤20 ng/mL) was observed in 93.5% of the patients: 57 (53.3%) showed levels <7 ng/mL. As primary outcome, sepsis-related mortality rate was higher in patients with vitamin D levels <7 ng/mL (50.9% versus 26%). Multivariate regression analysis showed that vitamin D concentration <7 ng/mL on ICU admission (p 0.01) and higher mean SAPS II (p <0.01) score were independent predictors of sepsis-related mortality. Patients with very low vitamin D levels suffered higher rate of microbiologically confirmed infections but a lower percentage of microbiological eradication with respect to patients whose values were >7 ng/mL (80.7% versus 58%, p 0.02; 35.3% versus 68%; p 0.03, respectively). Post hoc analysis showed that, in the extremely low vitamin D group, the 52 patients with pneumonia showed a longer duration of mechanical ventilation (9 days (3.75-12.5 days) versus 4 days (2-9 days), p 0.04) and the 66 with septic shock needed vasopressor support for a longer period of time (7 days (4-10 days) versus 4 days (2-7.25 days), p 0.02). Our results suggest that in critical septic patients extremely low vitamin D levels on admission may be a major determinant of clinical outcome. Benefits of vitamin D replacement therapy in this population should be elucidated.

Calcitriol-modulated human antibiotics: New pathophysiological aspects of vitamin D

Traditionally, calcitriol has been considered a calcium and phosphate regulating hormone, but has recently been shown to play a pivotal role in innate immunity. Many barrier and immune cells have membrane and intracellular receptors that recognize different microbial antigens. Activation of these receptors induces synthesis of 1α-hydroxylase, which acts on 25 hydroxyvitamin D to generate intracellular calcitriol. Calcitriol activates its receptor and enhances the synthesis of important human antibiotics like cathelicidin and β2-defensin while inhibiting hepcidin. These pluripotent peptides have an important role in innate immunity, and their regulation is abnormal in hypovitaminosis D. The literature on their secretion mechanisms, levels in different organic fluids, mechanism of action, and relationship with vitamin D is reviewed here.

Admission vitamin D status is associated with discharge destination in critically ill surgical patients

BACKGROUND

Discharge destination after critical illness is increasingly recognized as a valuable patient-centered outcome. Recently, vitamin D status has been shown to be associated with important outcomes such as length of stay (LOS) and mortality in intensive care unit (ICU) patients. Our goal was to investigate whether vitamin D status on ICU admission is associated with discharge destination.

METHODS

We performed a retrospective analysis from an ongoing prospective cohort study of vitamin D status in critical illness. Patients were recruited from two surgical ICUs at a single teaching hospital in Boston, Massachusetts. All patients had 25-hydroxyvitamin D (25OHD) levels measured within 24 h of ICU admission. Discharge destination was dichotomized as non-home or home. Locally weighted scatterplot smoothing (LOWESS) was used to graph the relationship between 25OHD levels and discharge destination. To investigate the association between 25OHD level and discharge destination, we performed logistic regression analyses, controlling for age, sex, race, body mass index, socioeconomic status, acute physiology and chronic health evaluation II score, need for emergent vs. non-emergent surgery, vitamin D supplementation status, and hospital LOS.

RESULTS

300 patients comprised the analytic cohort. Mean 25OHD level was 19 (standard deviation 8) ng/mL and 41 % of patients had a non-home discharge destination. LOWESS analysis demonstrated a near-inverse linear relationship between vitamin D status and non-home discharge destination to 25OHD levels around 10 ng/mL, with rapid flattening of the curve between levels of 10 and 20 ng/mL. Overall, 25OHD level at the outset of critical illness was inversely associated with non-home discharge destination (adjusted OR, 0.88; 95 % CI 0.82-0.95). When vitamin D status was dichotomized, patients with 25OHD levels <20 ng/mL had an almost 3-fold risk of a non-home discharge destination (adjusted OR, 2.74; 95 % CI 1.23-6.14) compared to patients with 25OHD levels ≥20 ng/mL.

CONCLUSIONS

Our results suggest that vitamin D status may be a modifiable risk factor for non-home discharge destination in surgical ICU patients. Future randomized, controlled trials are needed to determine whether vitamin D supplementation in surgical ICU patients can improve clinical outcomes such as the successful rate of discharge to home after critical illness.

Nasal Levels of Antimicrobial Peptides in Allergic Asthma Patients and Healthy Controls: Differences and Effect of a Short 1,25(OH)2 Vitamin D3 Treatment

Background

Allergy is often accompanied by infections and lower levels of antimicrobial peptides (AMPs). Vitamin D has been shown to increase expression of selected AMPs. In this study we investigated whether antimicrobial peptide levels in nasal secretions of allergic asthma patients are lower than in healthy controls, and whether administration of the active form of vitamin D (1,25(OH)₂D3) affects these antimicrobial peptide levels.

Methods

The levels of antimicrobial peptides in nasal secretions were compared between 19 allergic asthma patients and 23 healthy controls. The effect of seven days daily oral treatment with 2 μg 1,25(OH)₂D3 on antimicrobial peptides in nasal secretions was assessed in a placebo-controlled cross-over clinical study.

Results

Levels of neutrophil α-defensins (human neutrophil peptides 1–3; HNP1-3) and lipocalin 2 (LCN2; also known as NGAL) were significantly lower in asthmatics, but no differences in LL-37 and SLPI were detected. Treatment with a short-term 1,25(OH)₂D3 caused a small increase in HNP1-3, but not when the asthma and control groups were analyzed separately. LL-37, LCN2 and SLPI did not change after treatment with 1,25(OH)₂D3.

Conclusion

Levels of the antimicrobial peptides HNP1-3 and LCN2 are lower in nasal secretions in asthmatics and are not substantially affected by a short-term treatment with active vitamin D.

Effect of Cholecalciferol Supplementation on Vitamin D Status and Cathelicidin Levels in Sepsis: A Randomized, Placebo-Controlled Trial

OBJECTIVES

To compare changes in vitamin D status and cathelicidin (LL-37) levels in septic ICU patients treated with placebo versus cholecalciferol.

DESIGN

Randomized, placebo-controlled, trial.

SETTING

Medical and surgical ICUs of a single teaching hospital in Boston, MA.

PATIENTS

Thirty adult ICU patients.

INTERVENTIONS

Placebo (n = 10) versus 200,000 IU cholecalciferol (n = 10) versus 400,000 IU cholecalciferol (n = 10), within 24 hours of new-onset severe sepsis or septic shock.

MEASUREMENTS AND MAIN RESULTS

Blood samples were obtained at baseline (day 1) and on days 3, 5, and 7, to assess total 25-hydroxyvitamin D, as well as vitamin D-binding protein and albumin to calculate bioavailable 25-hydroxyvitamin D. Plasma LL-37 and high-sensitivity C-reactive protein levels were also measured. At baseline, median (interquartile range) plasma 25-hydroxyvitamin D was 17 ng/mL (13-22 ng/mL) and peaked by day 5 in both intervention groups. Groups were compared using Kruskal-Wallis tests. Relative to baseline, on day 5, median change in biomarkers for placebo, 200,000 IU cholecalciferol, and 400,000 IU cholecalciferol groups, respectively, were as follows: 1) total 25-hydroxyvitamin D, 3% (-3% to 8%), 49% (30-82%), and 69% (55-106%) (p < 0.001); 2) bioavailable 25-hydroxyvitamin D, 4% (-8% to 7%), 45% (40-70%), and 96% (58-136%) (p < 0.01); and 3) LL-37: -17% (-9% to -23%), 4% (-10% to 14%), and 30% (23-48%) (p = 0.04). Change in high-sensitivity C-reactive protein levels did not differ between groups. A positive correlation was observed between bioavailable 25-hydroxyvitamin D and LL-37 (Spearman ρ = 0.44; p = 0.03) but not for total 25-hydroxyvitamin D and LL-37.

CONCLUSIONS

High-dose cholecalciferol supplementation rapidly and safely improves 25-hydroxyvitamin D and bioavailable 25-hydroxyvitamin D levels in patients with severe sepsis or septic shock. Changes in bioavailable 25-hydroxyvitamin D are associated with concomitant increases in circulating LL-37 levels. Larger trials are needed to verify these findings and to assess whether optimizing vitamin D status improves sepsis-related clinical outcomes.

Vitamin D Deficiency and Critical Illness

OBJECTIVE

To determine the prevalence of vitamin D deficiency in critically ill children and assess its association with severity of illness and other outcomes associated with critical illness.

METHODS

Eighty children aged 2 mo to 12 y, admitted with medical conditions to the pediatric intensive care unit of a tertiary care hospital were enrolled in this prospective observational study. Vitamin D levels were obtained during the first hour of stay. Severity score was assessed using the Pediatric Risk of Mortality III (PRISM III) within first 12 h of admission.

RESULTS

Vitamin D deficiency {25-hydroxy vitamin D [25(OH)D] levels < 20 ng/ml} was observed in 67 (83.8%) children. Vitamin D deficient children had significantly higher PRISM III score compared to vitamin D sufficient children [10 (IQR:5-15) vs. 6 (IQR:3-7); p 0.0099]. 25(OH)D levels had a significant negative correlation with PRISM III score (ρ -0.3747; p 0.0006).

CONCLUSIONS

Vitamin D appears to be of utmost importance in critically ill children.

Inadequate vitamin D levels are associated with culture positive sepsis and poor outcomes in paediatric intensive care

AIM

This study aimed to assess vitamin D status, and its determinants, in paediatric patients with suspected sepsis who were admitted to a paediatric intensive care unit (PICU). We also investigated the association between vitamin D status and clinical outcomes.

METHODS

Serum 25-hydroxy vitamin D (25OHD) and clinical determinants were prospectively assessed in children with suspected sepsis (<12 years old) admitted to the PICU. The relationship between 25OHD and clinical outcomes was evaluated. Vitamin D status was also assessed in control children of a similar age.

RESULTS

We enrolled 120 children with suspected sepsis admitted to the PICU and 30 paediatric controls. 25OHD was <50 nmol/L in 59% of the children admitted to the PICU and 25OHD was lower than in the controls (47 ± 29 vs 66 ± 26 nmol/L, p < 0.001). After adjusting for potential confounders, 25OHD was strongly associated with culture positive sepsis (p < 0.001), the paediatric index of mortality (p = 0.026) and the duration of mechanical ventilation (p = 0.008). There was a negative correlation between 25OHD and C-reactive protein (CRP): each 0.1% decrease in 25OHD increased CRP (p = 0.04).

CONCLUSION

Children admitted to the PICU with suspected sepsis had lower 25OHD than controls and inadequate 25OHD status was associated with confirmed sepsis and poor outcomes.

Prevention of vitamin D deficiency in children following cardiac surgery: study protocol for a randomized controlled trial

BACKGROUND

Vitamin D is a pleiotropic hormone important for the recovery of organ systems after critical illness. Recent observational studies have suggested that three out of every four children are vitamin D deficient following cardiac surgery, with inadequate preoperative intake and surgical losses playing important contributory roles. Observed associations between postoperative levels, cardiovascular dysfunction and clinical course suggest that perioperative optimization of vitamin D status could improve outcome. With this two-arm, parallel, double blind, randomized controlled trial (RCT), we aim to compare immediate postoperative vitamin D status in children requiring cardiopulmonary bypass for congenital heart disease who receive preoperative daily high dose vitamin D supplementation (high-dose arm) with those who receive usual intake (low-dose arm).

METHODS/DESIGN

Eligibility requirements include age (>36 weeks, <18 years) and a congenital heart defect requiring cardiopulmonary bypass surgical correction. Enrollment of 62 participants will take place at a single Canadian tertiary care center over a period of 2 years. Children randomized to the high-dose group will receive age-based dosing that was informed by the Institute of Medicine (IOM) daily tolerable upper intake level (<1 year old = 1,600 IU/day, >1 year old = 2,400 IU/day). Children in the low-dose arm will receive usual care based on IOM recommendations (<1 year old = 400 IU, >1 year old = 600 IU). The primary outcome measure is immediate postoperative vitamin D status, using blood 25(OH)D.

DISCUSSION

Maintaining adequate postoperative vitamin D levels following surgery could represent an effective therapy to speed recovery following CHD surgery. The proposed research project will determine whether preoperative supplementation with a dosing regimen based on the IOM recommended daily upper tolerable intake will prevent postoperative vitamin-D deficiency in the majority of children. The results will then be used to inform the design of a large international RCT exploring whether preoperative optimization of vitamin D status might improve short and long-term outcomes in this vulnerable population.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier--NCT01838447 Date of registration: 11 April 2013.

Antimicrobial Peptides in Human Sepsis

Nearly 100 years ago, antimicrobial peptides (AMPs) were identified as an important part of innate immunity. They exist in species from bacteria to mammals and can be isolated in body fluids and on surfaces constitutively or induced by inflammation. Defensins have anti-bacterial effects against Gram-positive and Gram-negative bacteria as well as anti-viral and anti-yeast effects. Human neutrophil peptides (HNP) 1-3 and human beta-defensins (HBDs) 1-3 are some of the most important defensins in humans. Recent studies have demonstrated higher levels of HNP 1-3 and HBD-2 in sepsis. The bactericidal/permeability-increasing protein (BPI) attenuates local inflammatory response and decreases systemic toxicity of endotoxins. Moreover, BPI might reflect the severity of organ dysfunction in sepsis. Elevated plasma lactoferrin is detected in patients with organ failure. HNP 1-3, lactoferrin, BPI, and heparin-binding protein are increased in sepsis. Human lactoferrin peptide 1-11 (hLF 1-11) possesses antimicrobial activity and modulates inflammation. The recombinant form of lactoferrin [talactoferrin alpha (TLF)] has been shown to decrease mortality in critically ill patients. A phase II/III study with TLF in sepsis did not confirm this result. The growing number of multiresistant bacteria is an ongoing problem in sepsis therapy. Furthermore, antibiotics are known to promote the liberation of pro-inflammatory cell components and thus augment the severity of sepsis. Compared to antibiotics, AMPs kill bacteria but also neutralize pathogenic factors such as lipopolysaccharide. The obstacle to applying naturally occurring AMPs is their high nephro- and neurotoxicity. Therefore, the challenge is to develop peptides to treat septic patients effectively without causing harm. This overview focuses on natural and synthetic AMPs in human and experimental sepsis and their potential to provide significant improvements in the treatment of critically ill with severe infections.

Vitamin D and immune function in chronic kidney disease

The common causes of death in chronic kidney disease (CKD) patients are cardiovascular events and infectious disease. These patients are also predisposed to the development of vitamin D deficiency, which leads to an increased risk of immune dysfunction. Many extra-renal cells possess the capability to produce local active 1,25(OH)2D in an intracrine or paracrine fashion, even without kidney function. Vitamin D affects both the innate and adaptive immune systems. In innate immunity, vitamin D promotes production of cathelicidin and β-defensin 2 and enhances the capacity for autophagy via toll-like receptor activation as well as affects complement concentrations. In adaptive immunity, vitamin D suppresses the maturation of dendritic cells and weakens antigen presentation. Vitamin D also increases T helper (Th) 2 cytokine production and the efficiency of Treg lymphocytes but suppresses the secretion of Th1 and Th17 cytokines. In addition, vitamin D can decrease autoimmune disease activity. Vitamin D has been shown to play an important role in maintaining normal immune function and crosstalk between the innate and adaptive immune systems. Vitamin D deficiency may also contribute to deterioration of immune function and infectious disorders in CKD patients. However, it needs more evidence to support the requirements for vitamin D supplementation.