Traumatic brain injury and adrenal insufficiency: morning cortisol and cosyntropin stimulation tests

Introduction

Adrenal insufficiency (AI) has a great impact on the prognosis of patients with traumatic brain injury. There is a lack of consensus regarding the diagnostic criteria of AI. In these patients with acute stress we compared fasting cortisol, low and high dose cosyntropin stimulation tests to assess adrenal function in patients with moderate to severe traumatic brain injury.

Material and methods

This multicenter, cross-sectional study recruited 50 consecutive patients (aged between 15 and 70 years old) with moderate to severe traumatic brain injury who survived more than 5 days after the event. The patients’ adrenal function was assessed using the fasting cortisol, 1 and 250-µg ACTH stimulation tests.

Results

More cases of AI were detected by the 1-µg ACTH stimulation test compared to those detected by the basal serum cortisol level and 250-µg ACTH stimulation test. The κ test showed no agreement between these tests. The incidence of AI in the first 10 days after traumatic brain injury varied from 34% to 82% according to the various definitions of AI. The incidence of hypotension and need for vasopressors was higher in the patients diagnosed by the 250-µg ACTH stimulation test (p < 0.0001).

Conclusions

The incidence of secondary AI in moderate to severe traumatic brain injury seems to be high. A combination of stimulation test (either 250 or 1 µg) and basal cortisol level may improve diagnostic ability compared to either test alone. Hence performing both tests for the assessment of adrenal function in patients with traumatic brain injury is recommended.     

Plasma homocysteine concentration and blood pressure in healthy Iranian adults: the Tehran Homocysteine Survey (2003-2004)

Hypertension is a modifiable risk factor for cardiovascular disease, but its aetiology has not been fully elucidated. Recently, attention has been focused on the direct relations of plasma homocysteine (Hcy) to blood pressure (BP). The purpose of this study was to determine the relationship of Hcy with BP and other cardiovascular disease risk factors. This population-based study was a part of the Cardiovascular Risk Factors Survey and has been designed and conducted based on the methodology of the MONICA/WHO Project. A total of 1214 people aged 25-64 years were recruited using cluster sampling and assessed regarding standardized methods. BP was measured in seated position after a 10-min rest period. Blood samples were gathered and analysed according to standard methods. Variables were assessed in 1191 participants (416 men; 775 women). Mean age was higher in hypertensives compared to normotensives (P < 0.001). Mean Hcy was higher in hypertensives, but significant only in men (P < 0.031). Concurrent effects of Hcy, folate and vitamin B12 on hypertension indicated that Hcy acts as a risk factor and folate and vitamin B12 as protective factors; however, after adjustment, just vitamin B12 remained as a protective factor. Although we detected a simple correlation of Hcy with BP in Iranian adults, this relationship was no longer significant after applying an adjustment. In light of our observations, it is likely that the increased Hcy levels reported in hypertensive persons are concomitant rather than a precursor of hypertension.     

Optimal phase for coronary interpretations and correlation of ejection fraction using late-diastole and end-diastole imaging in cardiac computed tomography angiography: implications for prospective triggering

A typical acquisition protocol for multi-row detector computed tomography (MDCT) angiography is to obtain all phases of the cardiac cycle, allowing calculation of ejection fraction (EF) simultaneously with plaque burden. New MDCT protocols scanner, designed to reduce radiation, use prospectively acquired ECG gated image acquisition to obtain images at certain specific phases of the cardiac cycle with least coronary artery motion. These protocols do not we allow acquisition of functional data which involves measurement of ejection fraction requiring end-systolic and end-diastolic phases. We aimed to quantitatively identify the cardiac cycle phase that produced the optimal images as well as aimed to evaluate, if obtaining only 35% (end-systole) and 75% (as a surrogate for end-diastole) would be similar to obtaining the full cardiac cycle and calculating end diastolic volumes (EDV) and EF from the 35th and 95th percentile images. 1,085 patients with no history of coronary artery disease were included; 10 images separated by 10% of R–R interval were retrospectively constructed. Images with motion in the mid portion of RCA were graded from 1 to 3; with ‘1’ being no motion, ‘2’ if 0 to <1 mm motion, and ‘3’ if there is >1 mm motion and/or non-interpretable study. In a subgroup of 216 patients with EF > 50%, we measured left ventricular (LV) volumes in the 10 phases, and used those obtained during 25, 35, 75 and 95% phase to calculate the EF for each patient. The average heart rate (HR) for our patient group was 56.5 ± 8.4 (range 33–140). The distribution of image quality at all heart rates was 958 (88.3%) in Grade 1, 113 (10.42%) in Grade 2 and 14 (1.29%) in Grade 3 images. The area under the curve for optimum image quality (Grade 1 or 2) in patients with HR > 60 bpm for phase 75% was 0.77 ± 0.04 [95% CI: 0.61–0.87], while for similar heart rates the area under the curve for phases 75 + 65 + 55 + 45% combined was 0.92 ± 0.02. LV volume at 75% phase was strongly correlated with EDV (LV volume at 95% phase) (r = 0.970, P < 0.001). There was also a strong correlation between LVEF (75_35) and LVEF (95_35) (r = 0.93, P < 0.001). Subsequently, we developed a formula to correct for the decrement in LVEF using 35–75% phase: LVEF (95_35) = 0.783 × LVEF (75_35) + 20.68; adjusted R ² = 0.874, P < 0.001. Using 64 MDCT scanners, in order to acquire >90% interpretable studies, if HR < 60 bpm 75% phase of RR interval provides optimal images; while for HR > 60 analysis of images in 4 phases (75, 35, 45 and 55%) is needed. Our data demonstrates that LVEF can be predicted with reasonable accuracy by using data acquired in phases 35 and 75% of the R–R interval. Future prospective acquisition that obtains two phases (35 and 75%) will allow for motion free images of the coronary arteries and EF estimates in over 90% of patients.     

The effect of n-3 fatty acids on bone biomarkers in Iranian postmenopausal osteoporotic women: a randomized clinical trial

Recently, n-3 fatty acids are in the center of attention for their potent anti-inflammatory effects. Osteoporosis as a chronic senile disease is associated with inflammation, and the role of inflammatory mediators has been demonstrated in recent years. The beneficial effects of n-3 fatty acids on bone were proven in many animal studies, while to date, no conclusive data is available in human. The aim of this study was to evaluate the impact of n-3 fatty acids on bone biomarkers in osteoporotic postmenopausal women. Twenty-five osteoporotic postmenopausal women were recruited in the study and randomized in treatment and control groups. The patients received 900 mg n-3 fatty acid capsules or placebo per day for 6 months. Serum levels of osteocalcin, bone alkaline phosphatase (BALP), calcium, vitamin D, and parathormone and urine concentration of pyridinoline (Pyd) were measured at baseline, second month, and sixth month in both groups. In the treatment group, compared with baseline, at the second month, osteocalcin increased slightly; thereafter, it showed decrement trend until the end of the study. In the control group, it decreased all over the study. None of these changes was significant. BALP showed nonsignificant decrease from baseline over the time in both groups. Urine level of Pyd decreased significantly (P < 0.05) in the treatment group, while no significant change was seen in the control group. Serum calcium and vitamin D increased in both groups; however, changes were not significant. No significant changes were seen in calcium clearance and parathormone. In conclusion, n-3 fatty acids can decrease bone resorption; however, it could not affect bone formation significantly after 6 months treatment. Further investigations are recommended.     

Proinflammatory cytokines in response to insulin-induced hypoglycemic stress in healthy subjects

Hyperglycemic crises of diabetic ketoacidosis and nonketotic hyperglycemia are associated with elevation of counterregulatory hormones and proinflammatory cytokines, markers of lipid peroxidation, and oxidative stress. To investigate if other conditions besides hyperglycemia could evoke such a prompt increase in cytokine levels, lipid peroxidation, and oxidative stress markers, we induced hypoglycemic stress by standard insulin tolerance test and measured proinflammatory cytokines, markers of lipid peroxidation, reactive oxygen species (ROS), and counterregulatory hormones. Insulin tolerance test was performed in 13 healthy male subjects with no history of infection, cardiovascular risk factors, or abnormal glucose. At baseline and at 30, 45, 60, 120, and 240 minutes after insulin injection, the following parameters were measured: glucose, cortisol, corticotropin, epinephrine (EP), norepinephrine (NE), growth hormone, tumor necrosis factor (TNF)-α, interleukin (IL) 1β, IL-6, IL-8, free fatty acids, white blood cells, lipid peroxidation markers by thiobarbituric acid assay, and ROS by dichlorofluorescein method. The peak value of white blood cell count at 120 minutes was significantly associated with the peak values of NE at 30 minutes and cortisol at 60 minutes. By comparing the area under the curve of measured parameters, EP emerged as significant predictor of TNF-α (P = .05) and IL-8 (P = .027). Cortisol emerged as predictor of IL-1β significantly (P = .05). Corticotropin predicted area under the curve of IL-6 with borderline significance (P = .06). In the present study, insulin-induced hypoglycemia in nondiabetic male subjects is associated with increased proinflammatory cytokines (TNF-α, IL-1β, IL-6, and IL-8), markers of lipid peroxidation, ROS, and leukocytosis. Elevations of NE, EP, corticotropin, and cortisol in hypoglycaemia are associated with the elevation of the proinflammatory cytokines and leukocytosis.     

SLC34A3 intronic deletion in a new kindred with hereditary hypophosphatemic rickets with hypercalciuria

Objective: Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is an autosomal recessive form of hypophosphatemia with hyperphosphaturia, hypercalciuria, and hypercalcemia. In two reports on six affected kindreds with HHRH, the disease was mapped to chromosome 9q34, which contains the SLC34A3 gene that encodes the renal type 2c sodium-phosphate cotransporter. Our objective was to define the clinical course of these cases in a family with HHRH and to screen for SLC34A3 gene in order to determine whether these mutations are responsible for HHRH.Methods: After clinical and biochemical evaluations, the entire SLC34A3 gene was screened using PCR amplification followed by direct sequencing technique. In this paper, we describe a new kindred with HHRH and a case of progressive and complicated HHRH presenting at age 27 years.Results: We found 101-bp deletion in intron 9 of the SLC34A3 gene. The index patient was homozygous for this mutation which has been previously reported in a Caucasian population. This is the first report for presence of SLC34A3 intron 9 deletion in an Iranian population.Conclusions: These data showed that HHRH can be easily missed or underdiagnosed. Genetic evaluation of patients with familial hypercalciuria, hypophosphatemia and nephrolithiasis is needed for further information on the prevalence and management of this rare disorder. Conflict of interest:None declared.     

Evaluation of rabbit antibody response against 8 and 16 kDa recombinant subunits of antigen B from Echinococcus granulosus

ObjectiveTo immunize rabbits with 12 and 16 kDa recombinant subunits of antigen B from Echinococcus granulosus (E. granulosus) and measuring polyclonal antibody and humoral immune response using ELISA and gel diffusion.MethodsTwo mentioned antigens were cloned and expressed in expression vector and purified by affinity chromatography. Four young rabbits were selected and challenged intradermally with yielded recombinant antigens. Rabbits' sera were collected post infection and were tested using ELISA and gel diffusion for polyclonal antibody detection 10 days after last injection.ResultsThe specific antibody against the recombinant peptides was efficiently produced within 4 weeks post infection.ConclusionsProduced recombinants proteins could induce the immune response of the rabbits successfully. This process might improve the clarification of diagnosis and vaccination as regards hydatidosis.     

临床表现似视网膜母细胞瘤的脉络膜黑色素细胞瘤1例(英文)

我们报道罕见的脉络膜黑色素细胞瘤1例,以视网膜母细胞瘤之诊断行眼球内容物剜除术。患儿14mo,以左眼外斜视约10mo主诉就诊。眼科检查及影像学检查显示视网膜脱离并钙化病灶。患儿诊断为视网膜母细胞瘤,患眼行眼球内容物剜除术。组织病理学检查显示肿瘤细胞体积大,多面体型,核小,胞浆含大量黑色素颗粒,提示脉络膜及睫状体黑素细胞瘤之诊断。以往有脉络膜及睫状体黑色素细胞瘤表现类似与恶性黑素瘤的报道,但是,黑色素细胞瘤表现为钙化病灶及视网膜脱离,被误诊为视网膜母细胞瘤,此病例罕见,以往未见报道。