Pharmacokinetics and pharmacodynamics of systemically administered glucocorticoids

Pharmaceutical induction of ApoE secretion by multipotent mesenchymal stromal cells (MSCs)

Background

Apolipoprotein E (ApoE) is a molecular scavenger in the blood and brain. Aberrant function of the molecule causes formation of protein and lipid deposits or "plaques" that characterize Alzheimer's disease (AD) and atherosclerosis. There are three human isoforms of ApoE designated ε2, ε3, and ε4. Each isoform differentially affects the structure and function of the protein and thus the development of disease. Homozygosity for ApoE ε4 is associated with atherosclerosis and Alzheimer's disease whereas ApoE ε2 and ε3 tend to be protective. Furthermore, the ε2 form may cause forms of hyperlipoproteinemia. Therefore, introduction of ApoE ε3 may be beneficial to patients that are susceptible to or suffering from these diseases. Mesenchymal stem cells or multipotent mesenchymal stromal cells (MSCs) are adult progenitor cells found in numerous tissues. They are easily expanded in culture and engraft into host tissues when administered appropriately. Furthermore, MSCs are immunosuppressive and have been reported to engraft as allogeneic transplants. In our previous study, mouse MSCs (mMSCs) were implanted into the brains of ApoE null mice, resulting in production of small amounts of ApoE in the brain and attenuation of cognitive deficits. Therefore human MSCs (hMSCs) are a promising vector for the administration of ApoE ε3 in humans.

Results

Unlike mMSCs, hMSCs were found not to express ApoE in culture; therefore a molecular screen was performed for compounds that induce expression. PPARγ agonists, neural stem cell conditioned medium, osteo-inductive media, dexamethasone, and adipo-inductive media (AIM) were tested. Of the conditions tested, only AIM or dexamethasone induced sustained secretion of ApoE in MSCs and the duration of secretion was only limited by the length of time MSCs could be sustained in culture. Upon withdrawal of the inductive stimuli, the ApoE secretion persisted for a further 14 days.

Conclusion

The data demonstrated that pre-treatment and perhaps co-administration of MSCs homozygous for ApoE ε3 and dexamethasone may represent a novel therapy for severe instances of AD, atherosclerosis and other ApoE-related diseases.

The role of aggressive corticosteroid therapy in patients with juvenile dermatomyositis: a propensity score analysis

OBJECTIVE

To compare outcomes at 36 months in patients newly diagnosed with juvenile dermatomyositis (DM) treated with aggressive versus standard therapy.

METHODS

At diagnosis, 139 untreated juvenile DM patients were given aggressive therapy (intravenous methylprednisolone or oral prednisone 5-30 mg/kg/day; n = 76) or standard therapy (1-2 mg/kg/day; n = 63) by the treating physician. Aggressive therapy patients were more ill at diagnosis. Matching was based on the propensity for aggressive therapy because propensity scoring can reduce confounding by indication. Logistic regression of the matched data determined predictors of outcomes, controlling for clinical confounders and propensity score. Outcomes comprised Disease Activity Score (DAS) for skin and muscle, range of motion (ROM), and calcification.

RESULTS

Sex, race, and age were similar between groups, and initial DAS weakness and ROM significantly predicted the therapy chosen. Based on propensity scores, 42 patients from each group were well matched. In the matched pairs, there were no significant differences in outcomes. Methotrexate use (odds ratio [OR] 3.6, 95% confidence interval [95% CI] 1.15-11.5) and duration of untreated disease (OR 1.2, 95% CI 1-1.38) were associated with ROM loss, hydroxychloroquine use (OR 11.2, 95% CI 3.7-33) and calcification (OR 6.8, 95% CI 1.8-25.4) with persistent rash, abnormal baseline lactate dehydrogenase (OR 11.2, 95% CI 1.4-92) and age at onset (OR 1.3, 95% CI 1-1.4) with weakness, and duration of untreated disease (OR 1.2, 95% CI 1-1.39) with calcification.

CONCLUSION

Using a retrospective, nonrandomized design with propensity score matching, there was little difference in efficacy outcomes between aggressive and standard therapy; however, the sickest patients were treated with aggressive therapy and were not included in the matched analysis. Comprehensive clinical studies are needed to determine therapeutic pathways to the best outcome.

Synthesis and in vitro characterization of novel dextran-methylprednisolone conjugates with peptide linkers: effects of linker length on hydrolytic and enzymatic release of methylprednisolone and its peptidyl intermediates

To control the rate of release of methylprednisolone (MP) in lysosomes, new dextran-MP conjugates with peptide linkers were synthesized and characterized. Methylprednisolone succinate (MPS) was attached to dextran 25 kDa using linkers with 1-5 Gly residues. The release characteristics of the conjugates in pH 4.0 and 7.4 buffers, blood, liver lysosomes, and various lysosomal proteinases were determined using a size-exclusion and/or a newly developed reversed-phase HPLC method capable of simultaneous quantitation of MP, MPS, and all five possible MPS-peptidyl intermediates. We synthesized conjugates with >or=90% purity and 6.9-9.5% (w/w) degree of MP substitution. The conjugates were stable at pH 4.0, but released MP and intact MPS-peptidyl intermediates in the pH 7.4 buffer and rat blood, with faster degradation rates for longer linkers. Rat lysosomal fractions degraded the conjugates to MP and all the possible intermediates also at a rate directly proportional to the length of the peptide. Whereas the degradation of the conjugates by cysteine peptidases (papain or cathepsin B) was relatively substantial, no degradation was observed in the presence of aspartic (cathepsin D) or serine (trypsin) proteinases, which do not cleave peptide bonds with Gly. These newly developed dextran conjugates of MP show promise for controlled delivery of MP in lysosomes.

Liposomal glucocorticoids as tumor-targeted anti-angiogenic nanomedicine in B16 melanoma-bearing mice

This study evaluates whether the inhibitory effects of prednisolone phosphate (PLP) encapsulated in long-circulating liposomes (LCL-PLP) on tumor growth and tumor angiogenesis described previously can be generalized to other types of glucocorticoids (GC) encapsulated in LCL (LCL-GC). Four types of synthetic GC, i.e. budesonide disodium phosphate (BUP), dexamethasone disodium phosphate (DXP), methylprednisolone disodium phosphate (MPLP), and PLP, were selected based on the difference in their potency to activate the human glucocorticoid receptor. The effects of all LCL-GC on the production of angiogenic/inflammatory factors in vivo in the B16.F10 murine melanoma model as well as on the viability and proliferation of tumor cells and endothelial cells in vitro were investigated. Our results show that all four selected LCL-GC formulations inhibit tumor growth, albeit to different degrees. The differences in antitumor activity of LCL-GC correlate with their efficacy to suppress tumor angiogenesis and inflammation. The strongest antitumor effect is achieved by LCL-encapsulated BUP (LCL-BUP), due to the highest potency of BUP versus the other three GC types. The in vitro results presented herein suggest that LCL-BUP has strong cytotoxic effects on B16.F10 melanoma cells and the anti-proliferative effects of all LCL-GC towards angiogenic endothelial cells play a role in their antitumor activity.

Glucocorticoid therapy-induced memory deficits: acute versus chronic effects

Conditions with chronically elevated glucocorticoid levels are usually associated with declarative memory deficits. Considerable evidence suggests that long-term glucocorticoid exposure may cause cognitive impairment via cumulative and long-lasting influences on hippocampal function and morphology. However, because elevated glucocorticoid levels at the time of retention testing are also known to have direct impairing effects on memory retrieval, it is possible that such acute hormonal influences on retrieval processes contribute to the memory deficits found with chronic glucocorticoid exposure. To investigate this issue, we examined memory functions and hippocampal volume in 24 patients with rheumatoid arthritis who were treated either chronically (5.3 +/- 1.0 years, mean +/- SE) with low to moderate doses of prednisone (7.5 +/- 0.8 mg, mean +/- SE) or without glucocorticoids. In both groups, delayed recall of words learned 24 h earlier was assessed under conditions of either elevated or basal glucocorticoid levels in a double-blind, placebo-controlled crossover design. Although the findings in this patient population did not provide evidence for harmful effects of a history of chronic prednisone treatment on memory performance or hippocampal volume per se, acute prednisone administration 1 h before retention testing to either the steroid or nonsteroid group impaired word recall. Thus, these findings indicate that memory deficits observed under chronically elevated glucocorticoid levels result, at least in part, from acute and reversible glucocorticoid effects on memory retrieval.

Drug Insight: steroids in CNS infectious diseases--new indications for an old therapy

Infectious diseases of the CNS lead to overwhelming inflammatory processes within the brain and spinal cord that contribute substantially to patient morbidity and mortality. Pharmacological strategies to modulate inflammation have been investigated, although the resulting guidelines have sometimes been contradictory. Steroids have been proposed as adjunctive treatments for bacterial meningitis, tuberculous meningitis and herpes simplex virus encephalitis. Well-designed randomized controlled trials have established dexamethasone as an adjunctive therapy for adult patients receiving antibiotics for bacterial meningitis, and physicians prescribing the initial antibiotics need to be aware of current guidelines. Morbidity and mortality in patients with tuberculous meningitis exceeds 50%. Steroid treatments reduce mortality through an as yet unknown mechanism, although their effects on morbidity are less clear. Herpes simplex virus encephalitis is also associated with considerable morbidity and mortality. Despite a lack of randomized trials, there is some evidence that steroids used alongside antiviral therapy might be beneficial in this condition. As we discuss in this Review, systemic steroid treatment is an important aspect of treatment regimens for CNS infectious diseases, and the recent literature provides guidelines for the use of steroids in combination with appropriate antimicrobial therapy.

Pharmacokinetic study of oral prednisolone compared with intravenous methylprednisolone in patients with juvenile dermatomyositis

OBJECTIVE

To determine areas under the curve (AUCs) of oral prednisolone (OP) and intravenous methylprednisolone (IVMP) in patients with juvenile dermatomyositis (DM) and assess the association with nailfold end-row loops (ERLs). Patients with active disease have fewer ERLs that possibly occur in the gastrointestinal tract, impairing absorption of oral medications.

METHODS

Six patients with juvenile DM received 50 mg/m(2) of OP (day 1) and IVMP (day 2). Blood was drawn at baseline and at 5, 15, 30, 45, 60, and 90 minutes, and hourly (hours 2-8) after each dose. Samples were analyzed by reverse-phase high-performance liquid chromatography for levels of prednisolone and methylprednisolone. AUCs of OP and IVMP were determined by the trapezoid method; pharmacokinetic parameters were obtained using noncompartmental and compartmental analysis. ERLs were determined from freeze-frame video microscopy and nailfold capillaroscopy.

RESULTS

There was a trend toward significance in difference in mean AUC of IVMP (116.72 microg x ml/hour) compared with OP (65.16 microg x ml/hour; P = 0.059). Mean peak concentration was higher for IVMP (34.49 microg/ml) than OP (7.08 microg/ml); mean half-life was shorter for IVMP (1.90 hours) than OP (2.36 hours). There was an inverse association between DeltaAUCs (IVMP AUC - OP AUC) and ERLs (R = -0.68, P = 0.044).

CONCLUSION

Patients with juvenile DM and ERL loss may have decreased bioavailability of OP compared with IVMP. This can provide the rationale for greater efficacy of IVMP in patients with active vasculopathy of juvenile DM. Further studies investigating the pharmacokinetics and pharmacodynamics of high-dose IVMP need to be performed in patients with juvenile DM.

Fracture risk associated with different types of oral corticosteroids and effect of termination of corticosteroids on the risk of fractures

We conducted a case-control study on fracture risk associated with the use of orally administered prednisolone/prednisone, budesonide, methylprednisolone, and hydrocortisone to assess if the various preparations were associated with different fracture patterns. Cases were all subjects with any fracture sustained during the year 2000 (n = 124,655). For each case, three controls (n = 373,962) matched on age and gender were randomly drawn from the background population. Adjustments were made for concurrent diseases, use of other drugs, and a number of other factors. Oral prednisolone/prednisone was associated with a dose-dependent increase in fracture risk starting from a dose of around 6.7 mg/day. Oral budesonide was not associated with an increase in overall fracture risk, but the doses in general were low (<3 mg/day). Oral hydrocortisone was not associated with overall risk of fractures. Oral methylprednisolone was only used intermittently and was not associated with an increase in overall fracture risk at the low doses used. After termination of oral prednisolone/prednisone, it took more than 1 year for fracture risk to return to the levels of the background population. Oral prednisolone is associated with a dose-dependent increase in overall fracture risk. Budesonide at low doses did not seem to be associated with fracture risk. Hydrocortisone was not associated with an increase in the risk of fractures. It may take a year from last use of prednisolone/prednisone before fracture risk returns to that of the general population.

Increased rejection rates in cardiac transplant associated with dexamethasone

BACKGROUND

Peri-operative immunosuppression in cardiac transplantation includes the use of intravenous methylprednisolone. During a national shortage, intravenous dexamethasone was substituted for methylprednisolone at standard equivalencies. Methylprednisolone and dexamethasone are used interchangeably in many clinical settings; however, their equivalency has not been demonstrated.

METHODS

Forty-two consecutive cardiac transplant patients were studied retrospectively. All patients received standard triple immunosuppression. Eighteen patients received dexamethasone and 24 methylprednisolone. Twelve patients were included for comparison after the methylprednisolone shortage resolved. Endomyocardial biopsy (EMB) results graded as > or =1B (ISHLT classification) were considered positive for acute cellular rejection.

RESULTS

More patients who received dexamethasone as induction had cellular rejection (12/17; (70%) vs. 14/33; (42%); p=0.05). Four patients were excluded because of deaths unrelated to cardiac function. The increased rate of rejection seen during dexamethasone substitution declined after reinstitution of methylprednisolone (p=0.05).

CONCLUSIONS

Peri-operative high-dose dexamethasone in cardiac transplants was associated with higher rates of acute cellular rejection. The equivalencies of dexamethasone and methylprednisolone differ from accepted standards when used in pulse doses. Peri-operative use of glucocorticoids may rely on mechanisms that are different from those considered in the standard equivalency measures. Pulse doses of dexamethasone and methylprednisolone in transplantation may not be interchangeable at standard equivalencies.

Expression of IMPDH1 and IMPDH2 after transplantation and initiation of immunosuppression

BACKGROUND

Mycophenolic acid (MPA) mediates immunosuppressive effects by inhibiting inosine monophosphate dehydrogenase (IMPDH). Induction of IMPDH activity has been observed in whole blood and erythrocyte samples during immunosuppressive therapy. Information concerning the mechanisms for increased IMPDH activity is limited and the potential implications of induction have been debated.

METHODS

Whole blood, CD4+ cell, and reticulocyte samples were collected from 30 renal transplant patients pre- and posttransplantation. The expressions of two IMPDH isoforms, type 1 and 2, were analyzed by real-time reverse-transcription polymerase chain reaction and quantified using a housekeeping gene index. The IMPDH activity was determined by ultraviolet high-performance liquid chromatography.

RESULTS

Transplantation and the initiation of immunosuppressive therapy was associated with increased IMPDH1 (50-88%, P<0.0005) and decreased IMPDH2 (42-56%, P<0.0005) expression. In CD4+ cells, however, IMPDH2 increased (15%, P=0.009). These changes are probably related to glucocorticoid effects. Two weeks posttransplant, MPA-treated patients displayed elevated IMPDH 1 and 2 in reticulocytes, suggesting enzyme induction in these cells during prolonged MPA therapy. Patients with acute rejection during follow-up demonstrated higher IMPDH2 expression in CD4+ cells pretransplant than nonrejecting patients (median expression 1.26 vs. 0.87 respectively, P=0.017).

CONCLUSIONS

Knowledge of changes in IMPDH 1 and 2 expression after transplantation and initiation of immunosuppression is important considering the action of MPA on IMPDH and the potential for pharmacodynamic monitoring of MPA by measuring IMPDH activity. The expression of IMPDH2 in CD4+ cells pretransplant may be an indicator of immune activation.

Treatment of neuroblastoma-related opsoclonus-myoclonus-ataxia syndrome with high-dose dexamethasone pulses

Opsoclonus-myoclonus-ataxia-syndrome (OMS) represents a rare neuroblastoma-associated paraneoplastic syndrome that commonly results in neurologic deficits despite tumor resection and immunosuppressive therapy. We describe the response of five such children to high-dose dexamethasone pulses including two patients in whom previous glucocorticoids, rituximab, and cytostatic drugs were not successful. All patients had MYCN non-amplified tumors that were detected 1 to 7 months after the onset of the OMS or ataxia. This treatment resulted in a good partial response in three and in complete remission in two patients. Our results show that dexamethasone pulses are likely to be useful for both, first-line- and salvage-therapy for OMS-patients.

Hormonal influences in multiple sclerosis

The function of hormones has expanded to include immunomodulation and neuroprotection in addition to their classic roles. The story of how hormones influence inflammation and neuron and glial function is being slowly unraveled. There is increasing evidence that estrogen, progesterone, and testosterone contain immune responses and influence damage repair in the nervous system. Hormones such as prolactin and vitamin D are being explored as immunomodulators and may influence diseases such as multiple sclerosis (MS) or may be used therapeutically to modulate the immune response. More recently identified hormones, such as leptin and gherlin, may also influence the course of disease. This chapter reviews some of the evidence that supports a role for hormones in MS.

Effect of dexamethasone on glucose tolerance and fat metabolism in a diet-induced obesity mouse model

Prolonged exposure to elevated glucocorticoid levels is known to produce insulin resistance (IR), a hallmark of diabetes mellitus. Although not fully elucidated, the underlying molecular mechanisms by which glucocorticoids induce IR may provide potential targets for pharmacological interventions. Here we characterized muscle lipid metabolism in a dexamethasone-aggravated diet-induced obesity murine model of IR. Male C57BL/6 mice on a high-fat diet for 2 months when challenged with dexamethasone showed elevated food consumption and weight gain relative to age and diet-matched animals dosed with saline only. Dexamethasone treatment impaired glucose tolerance and significantly increased the intramyocellular lipid content in the tibialis anterior muscle (TA). A good correlation (r = 0.76, P < 0.01) was found between accumulation in intramyocellular lipid content in the TA and visceral adiposity. The linoleic acid (18:2) to polyunsaturated acid ratio was increased in the dexamethasone-treated animals (+29%; P < 0.01), suggesting a possible increase in stearoyl-CoA desaturase 2 activity, as reported in Sertoli cells. The treatment was also accompanied by a reduction in the percent fraction of omega-3 and long-chain polyunsaturated fatty acids in the TA. Analysis of the low-molecular-weight metabolites from muscle extracts showed that there was no dysregulation of muscle amino acids, as has been associated with dexamethasone-induced muscle proteolysis. In conclusion, dexamethasone-induced insulin resistance in diet-induced obese mice is associated with a profound perturbation of lipid metabolism. This is particularly true in the muscle, in which an increased uptake of circulating lipids along with a conversion into diabetogenic lipids can be observed.

Glucocorticoid receptor binding: a biphasic dependence on molecular size as revealed by the bilinear LinBiExp model

For corticosteroids, receptor-binding affinity (RBA) at the glucocorticoid receptor (GR) is a major determinant of therapeutic potential. Here, the results of a comprehensive quantitative analysis of relative RBA (rRBA) data obtained from more than a hundred active structures are reported. Because of a clear biphasic size-dependence, the recently introduced linearized biexponential (LinBiExp) model provided very good fit: for steroids that satisfy the main binding criteria at the GR, it accounts for close to 80% of the variability in the free energy of binding DeltaG0 (or logrRBA) data by using only two descriptors: calculated molecular volume and an indicator variable for the presence of 6alpha/9alpha-halogen or cyclic 16,17-acetal moieties. Accordingly, binding is strongest for corticosteroids close to an ideal size that is large enough to provide as large nonspecific (van der Waals-type) interactions as possible, but is not too large to have difficulty fitting due to size-limitations at the binding site. Binding affinity is dramatically increased by 6alpha- or 9alpha-halogenation or introduction of a cyclic 16,17-acetal moiety (in average, about 7-fold), but there is no significant increase after the first substitution. Known highly active glucocorticoids, such as betamethasone 17-monopropionate, fluticasone propionate, or mometasone furoate, indeed satisfy both of these criteria. For small-enough structures, the obtained size-dependency (slope) of the free energy of binding suggest that, as long as only nonspecific interactions are involved, addition of a methylene-sized non-hydrogen atom to the ligand structure increases DeltaG0 on average by about 1.5 kJ/mol, corresponding to an almost doubling of the binding affinity.

Continuous infusion of methylprednisolone via paediatric parenteral nutrition: A pharmacokinetic animal study

BACKGROUND & AIMS

The aim of our study consisted to measure the pharmacokinetic parameters of methylprednisolone administered in a continuous infusion of a paediatric parenteral nutrition mixture for 24h in the rabbit.

METHODS

Fourteen rabbits were split into two groups and assigned a different administration vehicle (all-in-one or two-in-one nutrition mixture). We used USC PACK* pharmacokinetics software to compare the influence of the composition of the paediatric parenteral nutritional solutions on the values of the pharmacokinetic parameters of methylprednisolone.

RESULTS

Neither the steady-state plasma concentrations of methylprednisolone hemisuccinate nor the values of the pharmacokinetic parameters of methylprednisolone differed significantly when administered in two-in-one or all-in-one nutrition mixtures.

CONCLUSIONS

The composition of the nutritional medium had no discernable effect on the bioavailability of methylprednisolone. Neither the speed at which the steady-state plasma concentration was reached, nor the values of the pharmacokinetic parameters of methylprednisolone were significantly modified.

Effects of acute prednisolone administration on exercise endurance and metabolism

OBJECTIVE

To examine whether acute glucocorticoid (GC) intake alters performance and selected hormonal and metabolic variables during submaximal exercise.

METHODS

In total, 14 recreational male athletes completed two cycling trials at 70-75% maximum O(2) uptake starting 3 h after an ingestion of either a lactose placebo or oral GC (20 mg of prednisolone) and continuing until exhaustion, according to a double-blind randomised protocol. Blood samples were collected at rest, after 10, 20, 30 minutes, and at exhaustion and recovery for measurement of growth hormone (GH), adrenocorticotropic hormone (ACTH), dehydroepiandrosterone (DHEA), prolactin, insulin, blood glucose, lactate and interleukin (IL)-6 determination.

RESULTS

Cycling duration was not significantly changed after GC or placebo administration (55.9 (5.2) v 48.8 (2.9) minutes, respectively). A decrease in ACTH and DHEA (p<0.01) was observed with GC during all of the experiments and in IL-6 after exhaustion (p<0.05). No change in basal, exercise or recovery GH, prolactin, insulin or lactate was found between the two treatments but blood glucose was significantly higher with GC (p<0.05) at any time point.

CONCLUSION

From these data, acute systemic GC administration does seem to alter some metabolic markers but did not influence performance during submaximal exercise.

Modeling receptor/gene-mediated effects of corticosteroids on hepatic tyrosine aminotransferase dynamics in rats: dual regulation by endogenous and exogenous corticosteroids

Receptor/gene-mediated effects of corticosteroids on hepatic tyrosine aminotransferase (TAT) were evaluated in normal rats. A group of normal male Wistar rats were injected with 50 mg/kg methylprednisolone (MPL) intramuscularly at the nadir of their plasma corticosterone (CST) rhythm (early light cycle) and sacrificed at various time points up to 96 h post-treatment. Blood and livers were collected to measure plasma MPL, CST, hepatic glucocorticoid receptor (GR) mRNA, cytosolic GR density, TAT mRNA, and TAT activity. The pharmacokinetics of MPL showed bi-exponential disposition with two first-order absorption components from the injection site and bioavailability was 21%. Plasma CST was reduced after MPL dosing, but resumed its daily circadian pattern within 36 h. Cytosolic receptor density was significantly suppressed (90%) and returned to baseline by 72 h resuming its biphasic pattern. Hepatic GR mRNA follows a circadian pattern which was disrupted by MPL and did not return during the study. MPL caused significant down-regulation (50%) in GR mRNA which was followed by a delayed rebound phase (60-70 h). Hepatic TAT mRNA and activity showed up-regulation as a consequence of MPL, and returned to their circadian baseline within 72 and 24 h of treatment. A mechanistic receptor/gene-mediated pharmacokinetic/pharmacodynamic model was able to satisfactorily describe the complex interplay of exogenous and endogenous corticosteroid effects on hepatic GR mRNA, cytosolic free GR, TAT mRNA, and TAT activity in normal rats.

Assessing the dynamics of nuclear glucocorticoid-receptor complex: adding flexibility to gene expression modeling

A retrospective analysis was performed to modify our fourth-generation pharmacodynamic model for glucocorticoid receptor (GR) dynamics with incorporation of more physiological features. This modified model was developed by integrating previously reported free cytosolic GR and GR mRNA data following single (10, 50 mg/kg) and dual (50 mg/kg at 0 and 24 hr) intravenous doses of methylprednisolone (MPL) in adrenalectomized (ADX) male Wistar rats with several in vitro studies describing real-time kinetics of the transfer of rat steroid-receptor complex from the cell cytosol to the nucleus. Additionally, free hepatic cytosolic GR and its mRNA data from a chronic infusion dosing study of MPL (0.1 and 0.3 mg/kg/hr) in male ADX Wistar rats were used to verify the predictability of the model. Incorporation of information regarding in vitro receptor kinetics allowed us to describe the receptor-mediated pharmacogenomic effects of MPL for a larger variety of genes in rat liver from microarray studies. These included early responsive gene like CCAAT/enhancer binding protein-beta (CEBP-beta), a transcription factor, as well as the later responsive gene for tyrosine aminotransferase (TAT), a classical biomarker of glucocorticoid (GC) genomic effects. This more mechanistic model of GR dynamics can be applied to characterize profiles for a greater number of genes in liver.

Population pharmacokinetic/pharmacodynamic modeling of systemic corticosteroid inhibition of whole blood lymphocytes: modeling interoccasion pharmacodynamic variability

PURPOSE

To develop a population pharmacokinetic/pharmacodynamic (PK/PD) model that characterizes the effects of major systemic corticosteroids on lymphocyte trafficking and responsiveness.

MATERIALS AND METHODS

Single, presumably equivalent, doses of intravenous hydrocortisone (HC), dexamethasone (DEX), methylprednisolone (MPL), and oral prednisolone (PNL) were administered to five healthy male subjects in a five--way crossover, placebo--controlled study. Measurements included plasma drug and cortisol concentrations, total lymphocyte counts, and whole blood lymphocyte proliferation (WBLP). Population data analysis was performed using a Monte Carlo-Parametric Expectation Maximization algorithm.

RESULTS

The final indirect, multi-component, mechanism-based model well captured the circadian rhythm exhibited in cortisol production and suppression, lymphocyte trafficking, and WBLP temporal profiles. In contrast to PK parameters, variability of drug concentrations producing 50% maximal immunosuppression (IC(50)) were larger between subjects (73-118%). The individual log-transformed reciprocal posterior Bayesian estimates of IC(50) for ex vivo WBLP were highly correlated with those determined in vitro for the four drugs (r ( 2 ) = 0.928).

CONCLUSIONS

The immunosuppressive dynamics of the four corticosteroids was well described by the population PK/PD model with the incorporation of inter-occasion variability for several model components. This study provides improvements in modeling systemic corticosteroid effects and demonstrates greater variability of system and dynamic parameters compared to pharmacokinetics.

Pharmacokinetics and pharmacodynamics of mycophenolic acid after enteric-coated mycophenolate versus mycophenolate mofetil in patients with progressive IgA nephritis

Mycophenolic acid can be administered orally using mycophenolate mofetil or enteric-coated mycophenolate. In renal transplant patients on immunosuppressant combination therapy, the overall mycophenolic acid exposure after oral dosing with mycophenolate mofetil and enteric-coated mycophenolate is similar. This study compared pharmacokinetics and pharmacodynamics of mycophenolic acid after equivalent doses of enteric-coated mycophenolate (360 mg twice daily) or mycophenolate mofetil (500 mg twice daily) in 7 patients with progressive IgA nephritis (glomerular filtration rate 20-35 mL/min) using a randomized crossover design. The pharmacokinetics of mycophenolic acid concentrations and pharmacodynamics (using inosine 5'-monophosphate dehydrogenase activity as a bio-marker) were sequentially monitored for 12 hours. After enteric-coated mycophenolate treatment, the mycophenolic acid peak concentration (Cmax = 12.8 vs 6.0 microg/mL, P < .05) and the overall exposure were significantly higher (AUC = 60.9 vs 40.7 microg.h/mL, P < .05), and the apparent clearance was significantly lower (CL/F = 7.9 vs 10.7 L/h, P < .05) as compared to that after mycophenolate mofetil. Paradoxically, inosine 5'-monophosphate dehydrogenase activity was not significantly different. In conclusion, the steady-state mycophenolic acid exposure was higher during treatment with enteric-coated mycophenolate as compared to mycophenolate mofetil, which might be explained by more extensive enterohepatic recycling of mycophenolic acid after administration of enteric-coated mycophenolate, whereas inosine 5'-monophosphate dehydrogenase suppression was not different.

High-dose methylprednisolone influences the physiology and virulence of Candida albicans ambiguously and enhances the candidacidal activity of the polyene antibiotic amphotericin B and the superoxide-generating agent menadione

Although exposure of Candida albicans cells to high-dose (4 mM) methylprednisolone stimulated microbial growth, germination rate in serum and phospholipase release, it also promoted the recognition of C. albicans cells by polymorphonuclear leukocytes. Pretreatment of C. albicans cells with methylprednisolone did not result in any increase in the pathogenicity of the fungus in intraperitoneal and intravenous mouse assays. Therefore, the virulence of C. albicans is unlikely to increase in patients treated with comparably high-dose methylprednisolone on skin and mucosal membranes. Methylprednisolone treatments also increased the production of conjugated dienes and thiobarbituric acid-reactive substances, and the menadione sensitivity of C. albicans cells, which can be explained by a significant decrease in the specific activities of several antioxidant enzymes. The combination of methylprednisolone with oxidants, e.g. in topical applications, may be of clinical importance when the predisposition to candidiasis is high. Methylprednisolone treatments negatively affected membrane fluidity and decreased the antifungal effects of both the polyene antibiotic nystatin and the ergosterol biosynthesis inhibitor lovastatin, and also enhanced the deleterious effects of the polyene antimycotic amphotericin B on C. albicans cells. These corticosteroid-polyene drug interactions should be considered in the treatment of C. albicans infections in patients with prolonged topical application of corticosteroids.

Impact of age, systemic glucocorticoids, and progressive knee arthritis on specific mRNA levels in different areas of the rabbit cornea

PURPOSE

To determine the influence of factors such as age, osteoarthritis (OA), and glucocorticoid treatment on total RNA and mRNA regulation in the cornea and how these factors differ between prepupillary and peripheral areas of the cornea.

METHODS

Molecular analyses of corneal tissue were performed using rabbits of different age groups and skeletally mature animals that had undergone anterior cruciate ligament (ACL) transection, an established model of knee OA. Systemic glucocorticoids were administered to cohorts of the osteoarthritic and control animals to determine the influence of distal joint disease on the corneal response. Corneal tissue was analyzed for changes in mRNA levels for several relevant genes: collagen I, collagen III, collagen V, decorin core protein, cyclooxygenase-2 (COX-2), glucocorticoid receptor, and the housekeeping gene beta-actin.

RESULTS

The corneal tissue was found to have diminishing total RNA with age, which is consistent with previous studies in the literature. Interestingly, in skeletally mature animals, distal joint OA was found to affect corneal mRNA levels for several important structural and inflammatory genes (collagen I, decorin core protein, and COX-2) in a manner that progressed with OA progression. Although systemic glucocorticoid treatment did not alter mRNA levels in the normal cornea, it did counteract the changes observed early after OA induction (3 weeks) while having less of an effect in later, more established arthritis (6 weeks).

CONCLUSIONS

This study reveals that distal joint OA can affect mRNA levels for several structural and inflammatory genes of the cornea, changes that seem to be suppressed by systemic glucocorticoid treatment. These findings indicate that OA has associated systemic factors that influence corneal cell metabolism.

Effect of perioperative corticosteroid use on the incidence of postcardiothoracic surgery atrial fibrillation and length of stay

BACKGROUND

While the mechanism underlying the development of post-cardiothoracic surgery atrial fibrillation has not been fully elucidated, it has been suggested that inflammation may play a causative role. Corticosteroids have been traditionally used to reduce inflammation, and when administered perioperatively, they may decrease the incidence of atrial fibrillation.

OBJECTIVE

The purpose of this study was to investigate the effects of corticosteroid administration on the incidence of post-cardiothoracic surgery atrial fibrillation and resultant hospital length of stay.

METHODS

A systematic literature search of MEDLINE, EMBASE, Web of Science, and the Cochrane Database of Systematic Reviews through July 2006 was conducted using specific search terms. A review of cardiology abstracts and a manual review of references were also performed. Studies that met the following criteria were included: randomized, controlled trials comparing patients receiving perioperative corticosteroids or placebo and reporting data on post-cardiothoracic surgery atrial fibrillation. A random-effects model was used.

RESULTS

Nine of the 1396 citations initially identified, representing 990 patients, met the inclusion criteria. Upon meta-analysis, corticosteroids significantly lowered patients' odds of developing post-cardiothoracic surgery atrial fibrillation by 45% (odds ratio [OR] 0.55; 95% confidence interval [CI] 0.39-0.78) and reduced hospital length of stay by approximately 1.6 days (weighted mean difference -1.59; 95% CI -2.96 to -0.21). Reductions in the incidence of post-cardiothoracic surgery atrial fibrillation appeared greatest in patients receiving intermediate doses of corticosteroid (50-210 mg dexamethasone equivalent), while both lower (up to 8 mg) and higher (236-2850 mg) dosing resulted in blunted effects.

CONCLUSION

Corticosteroids appear to reduce the incidence of post-cardiothoracic surgery atrial fibrillation and shorten hospital length of stay in randomized controlled trials.

Drug Insight: maintenance immunosuppression in kidney transplant recipients

Kidney transplantation is the treatment of choice for patients with end-stage renal disease, in part because of ongoing efforts towards improving immunosuppressive strategies. Although calcineurin inhibitors remain the mainstay of immunosuppression in kidney transplant recipients, within this class of drug there has been a shift from use of ciclosporin to use of tacrolimus. Mycophenolate mofetil and mycophenolate sodium are now the antimetabolites of choice. A new class of drugs (inhibitors of mammalian target of rapamycin) that includes sirolimus is being increasingly used in stable kidney transplant recipients. New data, however, indicate that a more cautious approach to the use of this drug is warranted. Many transplant centers are now using steroid avoidance, minimization and withdrawal protocols. The impact of these different drugs and therapeutic strategies on outcomes has to be weighed against their immunosuppressive benefit. As more and more community-based nephrologists and primary care physicians are becoming involved in the care of stable kidney transplant recipients, it is important for these clinicians to familiarize themselves with novel immunosuppressive drugs and their pharmacokinetic properties.

The pharmacological importance of cytochrome CYP3A4 in the palliation of symptoms: review and recommendations for avoiding adverse drug interactions

BACKGROUND

Adverse drug interactions are major causes of morbidity, hospitalizations, and mortality. The greatest risk of drug interactions occurs through in the cytochrome system. CYP3A4, the most prevalent cytochrome, accounts for 30-50% of drugs metabolized through type I enzymes.

MATERIALS AND METHODS

Palliative patients received medications for symptoms and co-morbidities, many of which are substrate, inhibitors, or promoters of CYP3A4 activity and expression. A literature review on CYP3A4 was performed pertinent to palliative medicine.

DISCUSSION

In this state of the art review, we discuss the CYP3A4 genetics, and kinetics and common medications, which are substrates or inhibitor/promoters of CYP3A4.

CONCLUSION

We made some recommendations for drug choices to avoid clinically important drug interaction.

Different responses to dexamethasone and prednisolone in the same depressed patients

RATIONALE

Patients with major depression show hypothalamic-pituitary-adrenal (HPA) axis hyperactivity, but the mechanisms underlying this abnormality are still unclear.

OBJECTIVES

We have compared two synthetic glucorticoids, dexamethasone and prednisolone, in their ability to suppress the hypothalamic-pituitary-adrenal (HPA) axis in depressed patients. Dexamethasone probes glucocorticoid receptor (GR) function, while prednisolone probes both GR and mineralocorticoid receptor (MR) function.

MATERIALS AND METHODS

We used a single-blind, repeated-measure design. We administered placebo, prednisolone (5 mg) or dexamethasone (0.5 mg), at 22:00, to 18 severe, treatment-resistant depressed inpatients (15 of them with a history of childhood trauma) and 14 healthy volunteers. On the following days, we collected salivary cortisol from 9:00 to 22:00.

RESULTS

Depressed patients had higher salivary cortisol levels compared with controls, at baseline and after both prednisolone and dexamethasone (p<0.001). Consistent with previous studies, depressed inpatients showed impaired suppression by dexamethasone: based on the analysis of the areas under the curve (AUCs), suppression by dexamethasone (0.5 mg) was -85% in controls vs -46% in depressed patients (p=0.018). However, the same depressed patients showed normal suppression by prednisolone (5 mg): suppression was -41% in controls and -36% in depressed patients (p=0.6).

CONCLUSIONS

We suggest that the additional effects of prednisolone on the MR explain the different responses to these glucocorticoids in the same depressed patients.

Perioperative management of immunosuppression

Current immunosuppressive regimens typically consist of two phases: induction phase (medications given at the time of the initial transplant) and maintenance therapy. Induction medications are given to decrease the occurrence of early acute rejection, avoid or minimise corticosteroids, and potentially induce long-term favourable immunoregulatory effects. As tolerance remains an elusive goal, life-long maintenance immunosuppression is required after all solid-organ transplantations. The various agents used in these two phases of immunosuppression are reviewed in this article. The similarities and differences between the agents within each class, with respect to efficacy and tolerability, are discussed.

Dexamethasone in adults with community-acquired bacterial meningitis

Bacterial meningitis in adults is a severe disease with high fatality and morbidity rates. Experimental studies have shown that the inflammatory response in the subarachnoid space is associated with an unfavourable outcome. In these experiments, corticosteroids, and in particular dexamethasone, were able to reduce the inflammatory cascades in the subarachnoid space. The use of corticosteroids as adjunctive therapy in adults with bacterial meningitis has been evaluated in six studies, performed over a time period of 40 years. Most studies on adjunctive dexamethasone therapy in adults with bacterial meningitis were limited by methodological flaws. In 2002, a study with sufficient statistical power to show significant differences was published. This European Dexamethasone Study showed that adjunctive dexamethasone therapy reduced the rate of unfavourable outcomes in adults with bacterial meningitis from 25% to 15%. In this study, adjunctive treatment with dexamethasone was given before or with the first dose of antibacterials, without serious adverse effects. A quantitative review showed a consistent beneficial effect of dexamethasone on mortality and a borderline statistical beneficial effect on neurological sequelae. On the basis of the available evidence, adjunctive dexamethasone therapy should be initiated before or with the first dose of antibacterials and continued for 4 days in all adults with suspected or proven bacterial meningitis, regardless of bacterial aetiology. In patients with both meningitis and septic shock, dexamethasone therapy cannot be unequivocally recommended, but the use of lower doses seems reasonable at present. Since prompt use of dexamethasone and appropriate antibacterials improves the prognosis of adults with bacterial meningitis, hospitals will require protocols to include dexamethasone with the initial antibacterial therapy.

Therapeutic efficacy of intra-cochlear administration of methylprednisolone after acoustic trauma caused by gunshot noise in guinea pigs

The therapeutic efficacy of cochlear infusion of methylprednisolone (MP) after an impulse noise trauma (170dB SPL peak) was evaluated in guinea pigs. The compound action potential threshold shifts were measured over a 14 days recovery period after the gunshot exposure. For each animal, one of the cochlea was perfused directly into the scala tympani with MP during 7 days via a mini-osmotic pump, whereas the other cochlea was not pump-implanted. The functional study of hearing was supplemented by histological analysis. Forty eight hours after the trauma, significant differences between auditory threshold shifts in the implanted and non-implanted ears were observed for frequencies above 8kHz. At day 7, the difference was significant for only one frequency and no difference was observed after 14 days recovery. Cochleograms showed that the hair cell losses were significantly lower in the MP treated ears. This work indicates that direct infusion of MP into perilymphatic space accelerates hearing recovery, reduces hair cell losses after impulse noise trauma but does not limit permanent threshold shifts.

Therapeutic doses of glucocorticoids: implications for oral medicine

Glucocorticoids can cause adverse systemic side-effects ranging from iatrogenic Cushing's syndrome during treatment, to hypothalamic-pituitary-adrenal axis suppression and clinically significant adrenal insufficiency when the agents are discontinued. While the oral route of administration is most often implicated, it is now becoming more apparent that inhaled and topical administration also can cause these effects. Given the high therapeutic value of glucocorticoids, the ability to prescribe these agents while maintaining a low risk-to-benefit ratio for patients is critical. The aim of this review is to provide oral healthcare practitioners with a practical guide to commonly used glucocorticoids, their adverse effects, and perioperative use.

Suppressor function of umbilical cord blood-derived CD4+CD25+ T-regulatory cells exposed to graft-versus-host disease drugs

BACKGROUND

This study examines the effects of the most commonly used graft-versus-host disease (GVHD) prophylactic drugs on inducing apoptosis and suppressor cell function of human umbilical cord blood (UCB) CD4+25+ Treg and CD4+25- cells.

METHODS

Cyclosporin A (CSA), methylprednisolone (MP), methotrexate (MTX), and mycophenolic acid (MPA) were added to the final 6 days of expansion cultures of Treg or CD4+25- T-cells isolated from the same donor and each concurrently cultured under the same conditions. Cell viability was measured for CD4+25+ as compared to CD4+25- T-cells and Treg function was assessed. The effects of these immunosuppressive drugs, Treg cells, or both also were tested in a primary allogeneic mixed lymphocyte response (MLR) response.

RESULTS

The cell viability percentages were lower for CD4+25- cells than for Treg cells when MP, MTX, or MPA was added for the last 6 days of an expansion culture. Under these interleukin (IL)-2 based expansion conditions, CSA had no effect. The addition of any of the four GVHD prophylactic agents to the expansion phase of culture did not reduce the MLR suppressive capacity of Treg cells. Overall MLR suppression was increased when Treg cells were added along with CSA and MP to a primary MLR culture, whereas MTX modestly reduced Treg suppression.

CONCLUSION

These data indicate a general resistance of expanded UCB Treg cells to GVHD immune suppressive agents and support trials to test UCB Treg infusions under the cover of GVHD prophylactic drugs in hematopoietic cell transplantation.

Glucocorticosteroids in football: use and misuse

BACKGROUND AND OBJECTIVES

Glucocorticosteroids are widely used in medicine and have shown unchallenged therapeutic potential in several chronic inflammatory and other diseases. They are also widely used in sports medicine for the treatment of conditions such as asthma and acute injuries. In fact, as banned substances, most requests for therapeutic use exemption concern glucocorticosteroids. Nevertheless, their beneficial effect in certain conditions in sports, where inflammation is only a secondary reaction, remains to be validated. This paper aimed to provide a comprehensive review of the literature covering the therapeutic use of glucocorticosteroids since 1977 in conditions ranging from chronic rheumatic illness to peritendinous or intra-articular injection in acute injuries.

METHODS

Search of the medical literature published between 1977 and 2006 using PubMed. Articles relevant to the question "When and if at all is the use of glucocorticosteroids justified in football?" were selected and analysed.

RESULTS AND CONCLUSIONS

The findings clearly point out that, despite the common use of glucocorticosteroids in acute injuries in sports, there is actually limited evidence of the true benefits of such a practice. Physicians must take the possible adverse effects into consideration. In an athlete with clinically verified asthma, inhalational glucocorticosteroids remain first line therapy. Finally, for the purposes of education and prevention of misuse, it should be stressed that a measurable performance enhancing effect of glucocorticoids could not be proved on the basis of the results of the scientific studies to date.

Transcriptional profiling of mesenchymal stromal cells from young and old rats in response to Dexamethasone

Background

Marrow-derived stromal cells (MSCs) maintain the capability of self-renewal and differentiation into multiple lineages in adult life. Age-related changes are recognized by a decline in the stemness potential that result in reduced regeneration potential of the skeleton. To explore the molecular events that underline skeletal physiology during aging we catalogued the profile of gene expression in ex vivo cultured MSCs derived from 3 and 15 month old rats. The ex vivo cultured cells were analyzed following challenge with or without Dexamethasone (Dex). RNA retrieved from these cells was analyzed using Affymetrix Gene Chips to compare the effect of Dex on gene expression in both age groups.

Results

The molecular mechanisms that underline skeletal senescence were studied by gene expression analysis of RNA harvested from MSCs. The analysis resulted in complex profiles of gene expression of various differentiation pathways. We revealed changes of lineage-specific gene expression; in general the pattern of expression included repression of proliferation and induction of differentiation. The functional analysis of genes clustered were related to major pathways; an increase in bone remodeling, osteogenesis and muscle formation, coupled with a decrease in adipogenesis. We demonstrated a Dex-related decrease in immune response and in genes that regulate bone resorption and an increase in osteoblastic differentiation. Myogenic-related genes and genes that regulate cell cycle were induced by Dex. While Dex repressed genes related to adipogenesis and catabolism, this decrease was complementary to an increase in expression of genes related to osteogenesis.

Conclusion

This study summarizes the genes expressed in the ex vivo cultured mesenchymal cells and their response to Dex. Functional clustering highlights the complexity of gene expression in MSCs and will advance the understanding of major pathways that trigger the natural changes underlining physiological aging. The high throughput analysis shed light on the anabolic effect of Dex and the relationship between osteogenesis, myogenesis and adipogenesis in the bone marrow cells.

Radiation Oncology Emergencies

Radiation therapy is an important and effective treatment modality when used in the management of oncologic emergencies. For any patient who has MSCC, ISCM, SVC syndrome, or life-threatening hemoptysis/obstruction, optimal management hinges on efficient multidisciplinary evaluation and communication to arrive at a treatment plan tailored to the individual patient. Optimal management may include steroids, surgery, chemotherapy, or bronchoscopic intervention. When radiation therapy is used, the total dose and fractionation schedule should be tailored to the disease setting and life expectancy of the patient.

Interleukin-10, T-lymphocytes, and cardiac output in children after ventricular septal defect repair: a pilot study

OBJECTIVE

To evaluate the acute inflammatory response and cardiac output in children after surgery for ventricular septal defect.

DESIGN AND SETTING

Prospective, observational study in a level III multidisciplinary neonatal and pediatric intensive care unit.

PATIENTS

Ten children undergoing open-heart surgery for ventricular septal defect.

INTERVENTIONS

All children received methylprednisolone (30 mg/kg) in cardiopulmonary bypass (CPB) prime.

MEASUREMENTS AND RESULTS

Before and after cardiopulmonary bypass, plasma interleukin-10 and tumor necrosis factor alpha were measured by enzyme-linked immunosorbent assay, and lymphocyte subsets in peripheral blood by flow cytometry. Relative values (post-/pre-CPB) of interleukin-10 and tumor necrosis factor alpha were calculated. The cardiac index (CI) was measured continuously beat-to-beat by a pulse contour analysis (PiCCO). Children above the cutoff value (median cardiac index value 3.0 l min(-1) m(-2)) were designated as the normal CI group and those below this value as the low CI group. In the normal CI group the relative values of interleukin-10 remained almost seven times higher than pre-CPB values at 24 h while in the low CI group they decreased almost to pre-CPB values. Furthermore, the normal CI group, but not the low CI group, exhibited more than threefold decrease in T-lymphocytes (lymphocyte T-cells, T-helper cells, and cytotoxic T-cells) 24 h after CPB.

CONCLUSIONS

Children operated on for ventricular septal defect developed either a normal or low CI. The higher relative values of interleukin-10 and lower counts of lymphocyte T-cells, T-helper and cytotoxic T-cells differentiated the normal CI group from the low CI group at 24 h after cardiopulmonary bypass.

Anesthetic management of patients with ornithine transcarbamylase deficiency

Ornithine transcarbamylase deficiency (OTCD) is the most common inborn error of the urea cycle. Several specific factors require care during anesthesia in patients with this condition to avoid metabolic decompensation with acute hyperammonemia and encephalopathy. We report monozygous twins with severe neonatal-onset OTCD undergoing general anesthesia twice each, with midazolam, s-ketamine, fentanyl and isoflurane in combination with surgical field infiltration with ropivacaine. Alternative pathway medication and high-caloric diet with 10% glucose solutions were continuously administered during the perioperative course. Both children were extubated within 10 min of the final suture, and their neurological state remained unchanged. Perioperatively, blood ammonia levels remained within the normal range.

[Adrenal cortex and steroids. Supplementary therapy in the perioperative phase]

Since the publication of two case reports that are considered to represent the first clinical demonstration of iatrogenic adrenal insufficiency, it has been the generally accepted practice to cover steroid-treated patients undergoing surgery with glucocorticoids in the perioperative period. Both the inclusion criteria for the patients and the extent of the substitution pattern have been selected on an empirical rather than on a rational basis. Scientific advances over the past 50 years in the knowledge of the hypothalamic-pituitary-adrenal system's physiology and the molecular mechanism of action of its biologically active components are, for the most part, not reflected in current clinical practice and instead seem to be ignored. Clinical and experimental evidence suggests, however, that even glucocorticoid-treated patients undergoing surgery do not require maximum stress doses of hydrocortisone, which should be reserved for the treatment of sepsis. With regard to the broad spectrum of efficacy of glucocorticoids and their side effects, revision and modification of the historical regimen appear prudent.

[Experiences with intraoperative application of prednisolone during Isshiki type I thyroplasty]

Laryngeal edema is considered a postoperative problem in phonosurgery. In a prospective study we examined if a single intraoperative application of prednisolone can decrease the incidence of postoperative laryngeal edema after Isshiki type I thyroplasty. We examined ten patients undergoing unilateral type I thyroplasty [seven men and three women, age range: 19-60 years (average: 48 years)]. In six patients we administered 250 mg prednisolone i.v. during surgery. In four patients no steroids were given at all. On the 1st and 2nd postoperative day, the larynx was examined in a clinical setting. Five of six patients who received intraoperative steroid medication had no postoperative laryngeal edema. Only in one of those patients we examined a small edema of the arytenoid region. In all four patients without steroid medication a postoperative edema of the ipsilateral arytenoid hump was seen. Thus, intraoperative intravenous steroid administration seems to prevent, or at least reduce, postoperative laryngeal edema. Only in one of those patients we examined a small edema of the arytenoid region.