Thyroid hormone metabolism in pediatric cardiac patients treated by continuous povidone–iodine irrigation for deep sternal wound infection

Objective: The purpose of this study was to assess the influence of povidone–iodine mediastinal irrigation used for the treatment of deep sternal wound infection (DSWI) on thyroid function. Methods: Thyroid function was studied in 18 pediatric cardiac patients treated with continuous povidone–iodine irrigation for DSWI. The median age of patients was 8 months (18 days–5.3 years). Serum concentrations of total triiodothyronine (TT3), total thyroxine (TT4), free triiodothyronine (FT3), free thyroxine (FT4), thyroid-stimulating hormone (TSH), reverse triiodothyronine (rT3) and thyroxine-binding globulin (TBG) were measured at three time points: (a) prior to mediastinal reexploration (before povidone–iodine exposure); (b) immediately after discontinuation of povidone–iodine irrigation; (c) 2 weeks after discontinuation of mediastinal irrigation. Urinary iodine excretion was examined on the last day of povidone–iodine exposure. Results: Prior to the mediastinal reexploration, the median TT3 and TT4 levels were below the normal range, then increased significantly to concentrations within the normal range. The median serum FT3 levels were within the normal range throughout the observation period, though a significant increase of FT3 levels was observed after discontinuation of irrigation. The median serum FT4 concentrations were within the normal range prior to irrigation and did not change significantly. The median rT3 levels were within the normal range, close to upper normal limit. The median TBG levels were within the normal range throughout the observation period, though a significant increase of TBG levels was observed during the period of mediastinal irrigation. The median TSH level was within the normal range prior to mediastinal irrigation and did not change significantly. Urinary iodine concentrations in infants with povidone–iodine irrigation were significantly higher 6700 μg/l (range, 1600–15 000 μg/l) than in the group of 53 healthy infants 200 μg/l (range, 20–780 μg/l, P<0,001). Conclusions: Our data showed that the use of povidone–iodine irrigation in the patients with DSWI has not lead to any significant alteration in thyroid function within the study period.     

Routine preoperative 123I-MIBG scintigraphy for patients with phaeochromocytoma is not necessary

BACKGROUND: Functional imaging using (123)I-meta-iodo-benzyl-guanetidine (MIBG) scintigraphy has alleged 100% specificity for phaeochromocytoma (PHAEO). Its benefit in patients with biochemical diagnosis of PHAEO is arguable when cross-sectional radiology can demonstrate the side-size of the adrenal tumours. MATERIALS AND METHODS: This is a retrospective review of clinical notes of patients undergoing adrenalectomy for PHAEO in a University centre. RESULTS: Between January 2000 and December 2007, adrenalectomy for PHAEO was performed on 66 patients (28 M and 38 F, aged 24-82 years). Diagnosis was demonstrated by raised 24-h urine catecholamines (n = 14) or metanephrines (n = 52). The side and size of adrenal tumours were demonstrated on computed tomography (n = 58) and/or magnetic resonance imaging (n = 20) scans. MIBG scans were performed in 38 patients. Four of these patients were found to have non-adrenal pathology (haemangioblastomas, haemangioma, a bronchogenic cyst and an angiomyolipoma); hence, the positive predictive value of MIBG scan was 90%. In a further five patients, MIBG raised the suspicion of local metastatic disease but this was not confirmed on operative findings and no recurrence was detected in these patients during 6-92-month follow-up. This led to an overall rate of false-positive rate of 23%. CONCLUSION: MIBG scintigraphy adds little to the routine preoperative management of patients with suspected PHAEO. Its use should be limited to the small minority of patients with negative cross-sectional imaging and those with recurrent or metastatic disease.     

High serum chemerin level in CKD patients is related to kidney function,but not to its adipose tissue overproduction

Abstract

Chemerin is an adipokine modulating inflammatory response and affecting glucose and lipid metabolism. These disturbances are common in CKD. The aim of the study was: (a) to evaluate circulating chemerin level at different stages of CKD; (b) to measure subcutaneous adipose tissue chemerin gene expression; (c) to estimate the efficiency of renal replacement therapy in serum chemerin removal. 187 patients were included into the study: a) 58 patients with CKD; (b) 29 patients on hemodialysis; (c) 20 patients after kidney transplantation. 80 subjects constituted control group. Serum chemerin concentration was estimated by ELISA. The adipose tissue chemerin mRNA level was measured by RT-qPCR. The mean serum chemerin concentration in CKD patients was 70% higher than in the control group (122.9?±?33.7 vs. 72.6?±?20.7?ng/mL; p?<?0.001) and it negatively correlated with eGFR (r?=??0.71, p?<?0.001). The equally high plasma chemerin level was found in HD patients and a HD session decreased it markedly (115.7?±?17.6 vs. 101.5?±?16.4?ng/mL; p?<?0.001). Only successful kidney transplantation allowed it to get down to the values noted in controls (74.8?±?16.0 vs. 72.6?±?20.7?ng/mL; n.s.). The level of subcutaneous adipose tissue chemerin mRNA in CKD patients was not different than in patients of the control group. The study demonstrates that elevated serum chemerin concentration in CKD patients: (a) is related to kidney function, but not to increased chemerin production by subcutaneous adipose tissue, and (b) it can be efficiently corrected by hemodialysis treatment and normalized by kidney transplantation.     

Multiple frequency bioimpedance is an adequate tool to assess total and regional fat mass in HIV-positive patients but not to diagnose HIV-associated lipoatrophy: a pilot study

Introduction

HIV-associated lipodystrophy syndrome causes systemic metabolic alterations and psychological distress that worsen the quality of life of these patients. An early detection should be considered to efficiently treat it. Objective criteria or reference indices are needed for an early diagnosis. Bioelectrical Impedance Analysis (BIA) is an operator-independent, repeatable and non-invasive method of body composition evaluation that is less expensive than dual-energy X-ray absorptiometry (DXA) and/or CT scans. The aims of this pilot study were to validate the data obtained by BIA to measure fat mass in HIV-positive patients with/without lipoatrophy and to determine if BIA correctly diagnoses lipoatrophy in HIV-positive patients.

Methods

Thirty-nine participants were included in this preliminary study. Fourteen were HIV-negative (eight men) whereas 25 were HIV-positive patients (17 men). Eleven of the HIV-positive patients were classified as lipoatrophic according to subjective evaluation by the physicians. Total and regional body composition was measured in basal conditions by DXA and by BIA. To obtain abdominal CT scan fat values, transverse slices with 6-mm thickness were acquired at the L4-L5 intervertebral space.

Results

BIA measurements of total and regional body fat were significantly correlated with those obtained by DXA (p < 0.05 to <0.01) in HIV-positive patients. However, agreement between methods was poor as not very high ICC (intraclass correlation coefficient) values were observed. BIA and DXA showed higher ICC values in lipoatrophic patients. The visceral index obtained by BIA was correlated with total and visceral fat in L4 measured by CT scan (r = 0.607 and r = 0.617, respectively, p < 0.01) in HIV-positive patients. The Fat Mass Ratio (FMR) calculated by BIA did not correlate or agree with DXA values.

Conclusions

Multi-frequency BIA could be an effective method to evaluate the evolution of total and regional fat composition in HIV-positive patients with/without lipoatrophy. The correlations between BIA and DXA improved in lipoatrophic patients and in men, suggesting that its efficacy depends on fat mass, gender and probably other factors. The visceral index obtained by BIA seems to be a reliable indicator of abdominal obesity. However, BIA did not fulfil the need for easy quantitative diagnostic tools for lipoatrophy, and it did not provide sufficient diagnostic cut-off values for this syndrome.     

Insulin use is not significantly predictive for prostate cancer mortality in diabetic patients: a 12-year follow-up study

Study Type – Prognosis (inception cohort) Level of Evidence 2a What's known on the subject? and What does the study add? Even though a lower risk of prostate cancer has been reported in patients with diabetes, they may have a higher risk of cancer development involving the liver, pancreas, endometrium, colorectum, breast and bladder. Insulin may have mitogenic properties besides its metabolic function. However, whether exogenous insulin use for glycaemic control in diabetic patients could increase the risk of prostate cancer has rarely been studied. This is the first prospective follow‐up study for up to 12 years to show that exogenous insulin use for glycaemic control in the diabetic patients is not significantly predictive for prostate cancer mortality.

OBJECTIVE

• ? To evaluate whether insulin use in diabetic patients could be predictive for prostate cancer mortality.

PATIENTS AND METHODS

• ? A total of 39 135 diabetic men aged ≥40 years from a nationally representative cohort were followed prospectively from 1995 to 2006 for prostate cancer mortality.
• ? Cox proportional hazards models were used to estimate the hazard ratios for the following independent variables: age, diabetes type, diabetes duration, body mass index, smoking, insulin use and area of residence.
• ? The models were created for patients aged ≥40 years and ≥65 years, separately; and before and after excluding patients with a duration between onset of diabetes and prostate cancer mortality <5 years.

RESULTS

• ? A total of 105 diabetic men died of prostate cancer during follow‐up.
• ? Age was the only significant risk factor.
• ? Insulin use was associated with an insignificantly higher risk of prostate cancer mortality ranging from 24% to 49%.
• ? When stratified by the duration of insulin use <5 and ≥5 years, a lack of significant association was also observed.

CONCLUSIONS

• ? Insulin use in diabetic patients does not significantly predict the mortality from prostate cancer.
• ? Further confirmation in other ethnicities is needed.

     

Estrogen receptor‐α is required for the osteogenic response to mechanical loading in a ligand‐independent manner involving its activation function 1 but not 2

Estrogen receptor‐α (ERα) is crucial for the adaptive response of bone to loading but the role of endogenous estradiol (E2) for this response is unclear. To determine in vivo the ligand dependency and relative roles of different ERα domains for the osteogenic response to mechanical loading, gene‐targeted mouse models with (1) a complete ERα inactivation (ERα^?/?), (2) specific inactivation of activation function 1 (AF‐1) in ERα (ERαAF‐1⁰), or (3) specific inactivation of ERαAF‐2 (ERαAF‐2⁰) were subjected to axial loading of tibia, in the presence or absence (ovariectomy [ovx]) of endogenous E2. Loading increased the cortical bone area in the tibia mainly as a result of an increased periosteal bone formation rate (BFR) and this osteogenic response was similar in gonadal intact and ovx mice, demonstrating that E2 (ligand) is not required for this response. Female ERα^?/? mice displayed a severely reduced osteogenic response to loading with changes in cortical area (?78% ± 15%, p < 0.01) and periosteal BFR (?81% ± 9%, p < 0.01) being significantly lower than in wild‐type (WT) mice. ERαAF‐1⁰ mice also displayed a reduced response to mechanical loading compared with WT mice (cortical area ?40% ± 11%, p < 0.05 and periosteal BFR ?41% ± 8%, p < 0.01), whereas the periosteal osteogenic response to loading was unaffected in ERαAF‐2⁰ mice. Mechanical loading of transgenic estrogen response element (ERE)‐luciferase reporter mice did not increase luciferase expression in cortical bone, suggesting that the loading response does not involve classical genomic ERE‐mediated pathways. In conclusion, ERα is required for the osteogenic response to mechanical loading in a ligand‐independent manner involving AF‐1 but not AF‐2. © 2013 American Society for Bone and Mineral Research