Iatrogenic Cushing's syndrome in an HIV-infected patient treated with inhaled corticosteroids (fluticasone propionate) and low dose ritonavir enhanced PI containing regimen

What we have to know about corticosteroids use during Sars-Cov-2 infection

PURPOSE

Glucocorticoids (GCs), alone or associated to other drugs, were widely used in the management of patients affected by severe acute respiratory syndrome caused by SARS-CoV-2 infection, during the recent COVID-19 outbreak. This review summarizes the available data on HPA axis impairment in GC-treated SARS-CoV-2 patients, focusing on the risk of adrenal insufficiency and on potential drug interactions during concomitant treatments.

METHODS

Literature on the impact of GCs therapy on HPA axis and on the consequences of coadministration of GCs and other drugs in SARS-CoV-2 patients has been reviewed.

RESULTS

GC treatment can cause symptoms of hypercortisolism, especially in patients with individual hypersensibility, or hypoadrenalism after drug withdrawal, due to hypothalamic-pituitary-adrenal (HPA) axis suppression, with consequences in terms of increased morbidity and mortality risk. On the other hand, in SARS-CoV-2-infected patient's cortisol secretion could be insufficient also due to critical illness-related corticosteroid insufficiency (CIRCI). In addition, in this clinical context, the co-administration of antiretroviral drugs and corticosteroids may trigger drug-drug interaction and enhance the exposure to the latter ones, metabolized through the CYP450 CYP3A pathway, severely impacting on HPA axis.

CONCLUSION

Physicians involved in the management of patients affected by COVID-19 should be aware of the need of an appropriate GC dose tapering, and of potential interaction of GCs with antiviral therapy and drugs used to treat associated co-morbidities.

A review of medications used to control and improve the signs and symptoms of COVID-19 patients

In December 2019, an unprecedented outbreak of pneumonia associated with a novel coronavirus disease 2019 (COVID-19) emerged in Wuhan City, Hubei province, China. The virus that caused the disease was officially named by the World Health Organization (WHO) as the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). According to the high transmission rate of SARS-CoV-2, it became a global pandemic and public health emergency within few months. Since SARS-CoV-2 is genetically 80% homologous with the SARS-CoVs family, it is hypothesized that medications developed for the treatment of SARS-CoVs may be useful in the control and management of SARS-CoV-2. In this regard, some medication being tested in clinical trials and in vitro studies include anti-viral RNA polymerase inhibitors, HIV-protease inhibitors, anti-inflammatory agents, angiotensin converting enzyme type 2 (ACE 2) blockers, and some other novel medications. In this communication, we reviewed the general characteristics of medications, medical usage, mechanism of action, as well as SARS-CoV-2 related trials.

Risk and Cost Associated With Drug-Drug Interactions Among Aging HIV Patients Receiving Combined Antiretroviral Therapy in France

Background

We aimed to describe the frequency, risk factors, and costs attributable to drug–drug interactions (DDIs) among an aging French HIV population.

Methods

We conducted a retrospective cohort study using French nationwide health care e-records: the SNIIRAM database. People living with HIV (PLWH) aged >65 years and receiving combined antiretroviral treatment (cART) during 2016 were included. A DDI was defined as “These drugs should not be co-administered,” represented by a red symbol on the University of Liverpool website. Attributable DDIs’ cost was defined as the difference between individuals with and without DDIs regarding all reimbursed health care acts.

Results

Overall, 9076 PLWH met the study criteria. Their baseline characteristics were: mean age, 71.3 ± 4.9 years; 25% female; median HIV duration (interquartile range [IQR]), 16.2 (9.5–20.3) years; median comorbidities (IQR), 2 (1–3). During 2016, they received a median (IQR) of 14 (9–21) comedications (non-cART), and 1529 individuals had at least 1 DDI (16.8%; 95% confidence interval [CI], 16.1–17.6). In multivariate analysis, raltegravir or dolutegravir plus 2 nucleoside reverse-transcriptase inhibitors (NRTIs) significantly and independently reduced the risk of DDIs (adjusted odds ratio [aOR], 0.02; 95% CI, 0.005–0.050; P < .0001) compared with non-nucleoside reverse-transcriptase inhibitor plus 2 NRTIs, whereas cART with boosted agents (protease inhibitors or elvitegravir) significantly increased the risk (aOR, 4.12; 95% CI, 3.34–5.10; P < .0001). Compared with propensity score–matched PLWH without DDIs, the presence of DDIs was associated with a $2693 additional cost per year (P < .0001).

Conclusions

The presence of DDIs is frequent and significantly increases health care costs in the aging population of PLWH.

Iatrogenic Cushing syndrome and adrenal insufficiency during concomitant therapy with ritonavir and fluticasone

Ritonavir is a potent inhibitor of the cytochrome P450 enzyme CYP3A4 and is subject to multiple drug–drug interactions. This becomes especially important when the patient is also taking medications metabolized through CYP3A pathway as increased and potentially toxic drug levels may ensue. Herein we present one such interaction wherein a 57 year old gentleman with human immunodeficiency virus (HIV) infection on highly active antiretroviral therapy that included ritonavir, had addition of fluticasone inhaler to his medication repertoire for treatment of chronic obstructive pulmonary disease. This resulted in severe osteoporosis, iatrogenic Cushing syndrome and adrenal insufficiency due to the potentiated systemic glucocorticoid effect of inhaled fluticasone by ritonavir. This case emphasizes the need for pharmacovigilance when managing patients on complex drug regimens for physicians treating HIV infected patients.

Osteoporosis in the at-risk asthmatic

The effect of inhaled glucocorticosteroids (ICS) on bone metabolism and subsequent osteoporosis is controversial. Explanations for this controversy include various study designs, duration of use, outcome measures, and population demographics of research studies with intranasal or inhalational ICS. Patients with poorly controlled asthma are at greatest risk of osteoporosis because they are commonly treated with intermittent or continuous systemic corticosteroids (SCS) or high-dose ICS. A 45-year-old Caucasian woman presents with moderate-to-severe asthma with frequent albuterol use and nighttime awakenings at least once weekly. She is on fluticasone/salmeterol 500/50 μg one inhalation twice daily and montelukast 10 mg/day. She requires prednisone 15 mg three times per day for 5 days up to three times a year. Is this patient at greater risk of osteopenia, characterized by a T-score between -1.0 and -2.5, and subsequent osteoporosis and an increased risk of fractures? If she has osteopenia, should she be treated with a bisphosphonate? The risk of osteoporosis and fracture increases significantly with frequent administration of SCS, and patients on such medications should undergo preventative measures and treatment. This study discuses factors that contribute to an increased risk of osteoporosis/osteopenia in patients with asthma and suggests recommendations based on the current literature.

Influence of low-dose ritonavir with and without darunavir on the pharmacokinetics and pharmacodynamics of inhaled beclomethasone

OBJECTIVE

To identify an alternative inhaled corticosteroid to fluticasone propionate that can be safely coadministered with HIV protease inhibitors, the safety and pharmacokinetics of beclomethasone dipropionate (BDP) and its active metabolite, beclomethasone 17-monopropionate (17-BMP), in combination with ritonavir (RTV) and darunavir/ritonavir (DRV/r) were assessed.

DESIGN

Open-label, prospective, randomized pharmacokinetic and pharmacodynamic study in healthy volunteers.

METHODS

Thirty healthy volunteers received inhaled 160 μg bid BDP for 14 days and were then randomized (1:1:1) into 3 groups: group 1 (control) remained on BDP alone for 28 days, group 2 received 100 mg bid BDP + RTV for 28 days, and group 3 received 600/100 mg bid BDP + DRV/r for 28 days. Pharmacokinetic sampling for 17-BMP was performed on days 14 and 28, and pharmacokinetic parameter values were compared within patients and between groups. Cortisol stimulation testing was also performed on days 1, 14, 28, and 42 and compared within and between groups.

RESULTS

Geometric mean ratios (day 28:day 14) (90% confidence interval) for 17-BMP area under the concentration-time curve in groups 1, 2, and 3, respectively, were 0.93 (0.81 to 1.06, P = 0.27), 2.08 (1.52 to 2.65, P = 0.006), and 0.89 (0.68 to 1.09, P = 0.61). There were no significant reductions in serum cortisol levels within or between groups (P > 0.05).

CONCLUSIONS

DRV/r did not increase 17-BMP exposure, whereas RTV alone produced a statistically significant but clinically inconsequential 2-fold increase in 17-BMP exposure. Adrenal suppression was not observed in any of the study groups. These data suggest that BDP can be safely coadministered with DRV/r and likely other RTV-boosted protease inhibitors.

Inhaled corticosteroid use in HIV-positive individuals taking protease inhibitors: a review of pharmacokinetics, case reports and clinical management

As a consequence of inhibition of the hepatic cytochrome P450 3A4 isozyme, treatment with HIV protease inhibitors can result in significant drug-drug interactions. One noteworthy interaction is between protease inhibitors and inhaled or intranasal corticosteroids. This interaction can result in adrenal insufficiency and iatrogenic Cushing's syndrome (with symptoms such as rapid weight gain, obesity, facial hirsutism and swelling), as well as hypertension, osteoporosis and decreased CD4 cell count. In this paper, we review and unite pharmacokinetic data, case reports and current research regarding this drug-drug interaction in order to suggest options for the clinical management of HIV-positive patients requiring treatment with protease inhibitors and inhaled or intranasal corticosteroids.

Inhaled fluticasone causes iatrogenic cushing's syndrome in patients treated with Ritonavir

INTRODUCTION

Ritonavir, a protease inhibitor (PI), is commonly used in the treatment of HIV-1 infection. It is a potent inhibitor of the hepatic cytochrome P450 superfamily. Therefore, its usage with other PI medications leads to significant increases in the levels of the latter PI, which allows a reduction in pill burden. Intranasal and inhaled corticosteroids are widely used for the treatment of allergic rhinitis and asthma. Inhaled steroids do not usually lead to systemic adverse events, since their plasma concentrations are quite low due to extensive first-pass metabolism and clearance by CYP3A4. However, the coadministration of Ritonavir with inhaled (or intranasal) corticosteroids may result in an increase in the plasma corticosteroid levels due to the potent CYP3A4 inhibition by Ritonavir. This may cause Cushing's syndrome (laboratory and clinical) with adrenal suppression.

METHODS

Plasma cortisol and urinary-free cortisol levels were determined using immunoassays. In the Synacthen test, plasma cortisol levels were measured at time 0 as well as at times 60, 120, and 150 minutes following an intramuscular injection of 0.25 mg Synacthen.

RESULTS

We present here three HIV-1 female patients aged 12, 55 and 65 years who developed iatrogenic Cushing's syndrome with adrenal suppression following the coadministration of Ritonavir and inhaled Fluticasone, both at the standard recommended doses.

CONCLUSIONS

The coadministration of Ritonavir and Fluticasone at the recommended doses caused, in our three patients, iatrogenic Cushing's syndrome with adrenal suppression. We suggest that this adverse event is underdiagnosed and high clinical suspicion is needed for early diagnosis and prenention of Addisonian crises. Thus, Fluticasone treatment should be avoided in patients who are treated with Ritonavir. Alternative therapeutic options for asthma control such as oral Montelukast or bronchodilators alone should be considered.

Ritonavir-boosted protease inhibitors in HIV therapy

The advent of combination antiretroviral therapy has led to significant improvement in the care of HIV-infected patients. Originally designed as a protease inhibitor (PI), ritonavir is currently exclusively used as a pharmacokinetic enhancer of other protease inhibitors, predominantly due to ritonavir's potent inhibition of the cytochrome P450 3A4 isoenzyme. Ritonavir-boosting of PIs decrease pill burden and frequency of dosing. Boosted PIs are recommended for first-line therapy in treatment and play a key role in the management of treatment-experienced patients. Potential problems associated with PIs include metabolic abnormalities (e.g. dyslipidemia), increased cardiovascular risk, and drug interactions.

Exogenous Cushing's syndrome due to topical corticosteroid application: case report and review literature

Prolonged use of topical corticosteroids causes systemic adverse effects including Cushing's syndrome and hypothalamic-pituitary-adrenal (HPA) axis suppression, which is less common than that of the oral or parenteral route. At least 43 cases with iatrogenic Cushing syndrome from very potent topical steroid usage (Clobetasol) in children and adult have been published over the last 35 years particularly in developing countries. In children group (n = 22), most are infants with diaper dermatitis and two cases who had started topical application at a very early age and died from severe disseminated CMV infection. For the adult group (n = 21), the most common purpose of steroid use was for treatment of Psoriasis. The recovery period of HPA axis suppression was 3.49 ± 2.92 and 3.84 ± 2.51 months in children and adult, respectively. We report on an 8-month-old female infant who developed Cushing's syndrome and adrenal insufficiency after diaper dermatitis treatment through the misuse of Clobetasol without doctor's prescription. Physiologic dose of hydrocortisone was prescribed to prevent an adrenal crisis for 3 months and discontinued when HPA axis recovery was confirmed by normal morning cortisol and ACTH levels.

Iatrogenic Cushing's syndrome in HIV-infected patients receiving ritonavir and inhaled fluticasone: description of 4 new cases and review of the literature

Protease inhibitors boosted with ritonavir can lead to drug-drug interactions, particularly with inhaled corticosteroids such as fluticasone, because of the potent inhibition of cytochrome P450-3A4 activity. We report 4 cases of iatrogenic Cushing's syndrome after concomitant administration of inhaled fluticasone and antiretroviral therapy including a protease inhibitor boosted with ritonavir. Although typical manifestations were present, diagnosis of Cushing's syndrome was delayed because the patients were suspected to have antiretroviral therapy-associated lipodystrophy, which shares common clinical features with Cushing's syndrome. Biochemical tests confirmed iatrogenic Cushing's syndrome and clinical symptoms resolved after stopping ritonavir or fluticasone. The differences between the clinical symptoms of Cushing's syndrome and lipodystrophy are discussed as well as their frequency in the cases reported in the literature. The recommendation that concomitant administration of inhaled or intranasal fluticasone and ritonavir be prohibited must be implemented among practitioners who treat HIV-infected patients, and if long-term inhaled steroids are required, other drugs should be preferred.

Influence of antiretroviral drugs on the pharmacokinetics of prednisolone in HIV-infected individuals

BACKGROUND

Corticosteroids are cytochrome P450 3A4 substrates, which have been associated with toxicities in patients receiving cytochrome P450 3A4 inhibitors such as human immunodeficiency virus protease inhibitors. In a study in healthy volunteers, ritonavir significantly increased prednisolone exposure.

METHODS

We investigated the influence of antiretroviral (ARV) medications on prednisolone pharmacokinetics in 3 groups of 10 human immunodeficiency virus-infected subjects. One group received lopinavir/ritonavir, and another efavirenz, as part of their ARV regimen; a third group did not receive ARV medications. Each subject received a single 20-mg prednisone dose followed by serial blood sampling for prednisolone. Prednisolone pharmacokinetics were compared among the groups.

RESULTS

Area under the concentration-time curve was significantly lower in efavirenz recipients versus subjects receiving lopinavir/ritonavir (geometric mean ratio = 0.60, P = 0.01). Average prednisolone area under the concentration-time curve was higher in subjects taking lopinavir/ritonavir versus subjects not on ARVs; however, this difference was not significant (P > 0.05).

CONCLUSIONS

These data indicate that prednisolone concentrations may fluctuate widely when human immunodeficiency virus-positive individuals established on efavirenz therapy change to lopinavir/ritonavir or vice versa.

[Antiretroviral drug toxicity in human immunodeficiency virus infected children]

Paediatric Human Immunodeficiency Virus infection (HIV) nowadays is a chronic disease with an excellent long term prognosis, but lifelong combined antiretroviral treatment is required. However, an improved quality of life in this population is limited by adverse drug effects. The highest risk of treatment toxicity is developing a complete metabolic syndrome including: Hyperlipemia, lipodystrophy, insulin resistance, lactic acidosis, osteopenia, hypertension, and specific system and organ toxicity, such as the kidney, liver, CNS or bone marrow. The risk of cardiovascular disease adult life and also definitive bone mass damage are the most significant metabolic costs that have to paid for increased survival. Most of these toxicities were able to be adequately treated but, pharmacological interferences, patient intolerance and the high number of drugs are the problems that limit the adherence to treatment, which is essential for a good therapeutical efficacy. In this article, we present four HIV paediatric patients who presented with almost the whole range of metabolic toxicities, and a practical overview of therapeutical management.

Exogenous Cushing syndrome with inhaled fluticasone in a child receiving lopinavir/ritonavir

OBJECTIVE

To describe a case of Cushing syndrome in a child during concurrent use of inhaled fluticasone propionate, nasal mometasone, and a highly active antiretroviral regimen including lopinavir/ritonavir.

CASE SUMMARY

A 9-year-old boy with HIV infection and asthma developed moon facies, increased facial hair, and increased weight after fluticasone propionate inhalation (1 puff; 220 microg) therapy was begun. His antiretroviral regimen contained the protease inhibitor combination lopinavir/ritonavir at a dose of 216/54 mg twice daily, and he had been stable for the previous 5 years. He had also been receiving intranasal mometasone for 11 months for the management of allergic rhinitis. Serum cortisol and adrenocorticotropic hormone levels were consistent with adrenal suppression. These physical findings and symptoms and laboratory values normalized after discontinuation of the fluticasone propionate. The Naranjo probability scale indicated that a probable interaction occurred between lopinavir/ritonavir and fluticasone propionate, leading to subsequent adrenal suppression.

DISCUSSION

Protease inhibitors are associated with numerous drug interactions due to inhibition of the CYP3A4 isoenzyme. Pharmaceutical agents used to treat comorbidities in HIV-infected individuals often can interact with protease inhibitors, leading to toxic drug concentrations or untoward effects. Inhaled corticosteroids such as fluticasone propionate are often necessary to treat asthma in young children and are metabolized by CYP3A4. Interactions between protease inhibitors and inhaled fluticasone propionate have been reported in the adult population, but reports are limited in the pediatric literature.

CONCLUSIONS

This case raises awareness of the interaction between fluticasone propionate and lopinavir/ritonavir and adverse effects in children receiving both medications.

[Treatment of iatrogenic Cushing syndrome: questions of glucocorticoid withdrawal]

Iatrogenic Cushing's syndrome is the most common form of hypercortisolism. Glucocorticoids are widely used for the treatment of various diseases, often in high doses that may lead to the development of severe hypercortisolism. Iatrogenic hypercortisolism is unique, as the application of exogenous glucocorticoids leads to the simultaneous presence of symptoms specific for hypercortisolism and the suppression of the endogenous hypothalamic-pituitary-adrenal axis. The principal question of its therapy is related to the problem of glucocorticoid withdrawal. There is considerable interindividual variability in the suppression and recovery of the hypothalamic-pituitary-adrenal axis, therefore, glucocorticoid withdrawal and substitution can only be conducted in a stepwise manner with careful clinical follow-up and regular laboratory examinations regarding endogenous hypothalamic-pituitary-adrenal axis activity. Three major complications which can be associated with glucocorticoid withdrawal are: i. reactivation of the underlying disease, ii. secondary adrenal insufficiency, iii. steroid withdrawal syndrome. Here, the authors summarize the most important aspects of this area based on their clinical experience and the available literature data.

Ritonavir-fluticasone interaction causing Cushing syndrome in HIV-infected children and adolescents

BACKGROUND

Ritonavir, a potent inhibitor of CYP3A4 enzyme, can lead to high systemic concentrations of fluticasone when these 2 drugs are coadministered. Exogenous Cushing syndrome (CS) in HIV-infected patients receiving ritonavir and fluticasone has been reported frequently in adults but not in children. Three patients, all receiving ritonavir-fluticasone, developed weight gain and altered fat distribution concerning for either lipodystrophy or CS.

METHODS

Three patients were initially identified by their clinicians as having weight gain and altered fat distribution concerning for either lipodystrophy or CS. All 3 patients were receiving fluticasone and ritonavir, leading to concern about a potential medication interaction. After suspecting exogenous CS, all patient medication lists were reviewed to identify all children prescribed ritonavir-fluticasone. Blood adrenocorticotropic hormone (ACTH) and cortisol were obtained during routine clinic visits. Medication history, laboratory data and physical examination findings were abstracted from medical records.

RESULTS

Seventeen (9%) of 189 patients in this pediatric HIV clinic had been prescribed ritonavir-fluticasone. Of 7 patients still taking ritonavir-fluticasone, CS features were present in 4 (57%) patients, including the 3 patients initially suspected of CS or lipodystrophy. Five (71%) patients, including all 4 with CS features, had low serum concentrations: median cortisol <0.2 microg/dL (normal, <0.2 microg/dL). Three of these 5 had ACTH measured, all of which were low: median ACTH 3.0 pmol/L (range, 2.2-<5.0 pmol/L). One patient taking ritonavir-fluticasone had suppressed cortisol but no CS features. The 2 patients with normal serum cortisol and ACTH values had persistent HIV viremia and were suspected of medication nonadherence. Clinical and laboratory abnormalities generally normalized in affected patients within 3 months after discontinuation of fluticasone alone (2) and ritonavir-fluticasone (3).

CONCLUSIONS

Pediatric HIV physicians frequently prescribe fluticasone and ritonavir together. The combination can cause CS and adrenal suppression in children, potentially leading to misdiagnosis of lipodystrophy syndrome and to increased risk of adrenal crisis during acute illness. Alternatives to fluticasone should be used for treating children receiving ritonavir.

Antiretroviral therapy 2006: Pharmacology, applications, and special situations

As we approach the completion of the first 25 years of the human immunodeficiency virus (HIV) epidemic, there have been dramatic improvements in the care of patients with HIV infection. These have prolonged life and decreased morbidity. There are twenty currently available antiretrovirals approved in the United States for the treatment of this infection. The medications, including their pharmacokinetic properties, side effects, and dosing are reviewed. In addition, the current approach to the use of these medicines is discussed. We have included a section addressing common comorbid conditions including hepatitis B and C along with tuberculosis.

Cushing syndrome with secondary adrenal insufficiency from concomitant therapy with ritonavir and fluticasone

We present 2 cases of Cushing syndrome with secondary adrenal insufficiency from concomitant use of ritonavir and inhaled corticosteroids in children with human immunodeficiency virus infection. These cases highlight the need for special consideration when treatment with an inhaled/intranasal corticosteroid is indicated in children receiving antiretroviral therapy.

Therapeutic drug monitoring of atazanavir: surveillance of pharmacotherapy in the clinic

BACKGROUND

Therapeutic failure with antiretroviral therapy (ART) is a substantial issue where viral rebound, viral resistance and drug-related toxicity remain serious concerns. Drug exposure-response relationships have been described for the protease inhibitors, pharmacokinetic variability is substantial for this class of drugs and drug interactions can also alter ART exposure. Given this background we established a therapeutic drug monitoring (TDM) service to monitor atazanavir (ATV) plasma concentrations early after the therapy was made available to treatment-experienced people infected with HIV who were managed in a clinical setting.

METHODS

This was a prospective observational study which evaluated plasma samples from 110 highly treatment-experienced people with HIV using TDM and applied pharmacokinetic analysis over a five month period.

RESULTS

ATV trough concentrations exhibited substantial intersubject variability (<25-2108 microg l(-1)). A substantial number of subjects (50%,13/26) who received ATV400 mg daily had low exposure to ATV. Serum bilirubin concentrations correlated significantly with higher ATV trough concentrations (rho = 0.803; P < 0.001) and 55% (29/53) of subjects who received ATV300/100 mg RTV daily had plasma concentrations above a proposed target concentration associated with elevated bilirubin concentrations. This study confirmed low ATV exposure in eight subjects with HIV receiving ATV 400 mg daily. Reasons for low ATV exposure in this cohort include administration of interacting drugs, including a possible interaction with ritonavir, fluticasone and ATV, impaired ATV absorption secondary to suspected achlorhydria and potential interactions with colchicine and nandrolone. Viral load remained undetectable in most of these subjects with low ATV exposure.

CONCLUSIONS

TDM and targeted pharmacokinetic studies should be viewed as fundamental tools in the development and clinical application of ART, to improve pharmacotherapy for people with HIV.

The risk/benefit of inhaled corticosteroids in chronic obstructive pulmonary disease

Although inhaled corticosteroids have a well defined role in asthma therapy, their use remains controversial in nonasthmatic, smoking-related chronic obstructive pulmonary disease (COPD). Some studies have shown an effect of inhaled corticosteroids on airway inflammation in COPD, but the clinical relevance of these results is unknown. Data from five long-term, large studies, provide evidence that prolonged treatment with inhaled corticosteroids does not modify the rate of decline of forced expiratory volume in one second (FEV1) in patients with COPD and no reversibility to short-acting beta(2)-agonists. FEV1 was slightly improved over the first six months of treatment and lower reactivity in response to methacholine challenge has been observed. Improvement of respiratory symptoms and health status were also reported. A reduction of exacerbations rate was observed in two studies. No survival benefit was demonstrated. Two recent reports suggest that long term use of inhaled corticosteroids in COPD patients improves quality-adjusted life expectancy and is cost-effective. Combination therapy with inhaled corticosteroids and long-acting beta(2)-agonists have proven benefit in four long term large studies compared to placebo for FEV1, exacerbation rate, symptoms and health status. However, only two studies found that combination therapy was more effective than long-acting beta(2)-agonists alone for symptoms and health status improvement. The long term safety of inhaled corticosteroids is not known in COPD patients but topical adverse effects, and systemic effects such as a decrease of bone density of lumbar spine and femur and cutaneous adverse effects, have been reported after three years of treatment. However, three recent observational studies found a slight increase in the risk of fractures (hip, upper extremities and vertebral) in association with high doses of inhaled corticotherapy.

Prednisolone Pharmacokinetics in the Presence and Absence of Ritonavir After Oral Prednisone Administration to Healthy Volunteers

Corticosteroid therapy has been associated with bone toxicities (eg, osteonecrosis) and Cushing syndrome in HIV-infected patients; this may be partially attributable to a pharmacokinetic drug interaction between HIV protease inhibitors and corticosteroids. The purpose of this study was to characterize the influence of low-dose ritonavir on prednisolone pharmacokinetics in healthy subjects. Ten HIV-seronegative volunteers were given single oral doses of prednisone, 20 mg, before (baseline) and after receiving ritonavir, 200 mg, twice daily for 4 and 14 days. After each prednisone dose, serial blood samples were collected and prednisolone concentrations were determined; pharmacokinetic parameter values were compared between the groups. Geometric mean ratios (GMRs, 90% confidence interval [CI]) of the prednisolone area under the plasma concentration versus time curve (AUC0-infinity) after 4 and 14 days of ritonavir versus baseline were 1.41 (90% CI: 1.08 to 1.74) and 1.30 (90% CI: 1.09 to 1.49), respectively (P = 0.002 and P = 0.004, respectively). GMRs of prednisolone apparent oral clearance (Cl/F) were 0.71 (09% CI: 0.57 to 0.93) and 0.77 (90% CI: 0.67 to 0.92) after 4 and 14 days of ritonavir versus baseline, respectively (P = 0.0004 and P = 0.0003, respectively). Ritonavir significantly increased the systemic exposure of prednisolone in healthy subjects. Results from this investigation suggest that corticosteroid exposure is likely elevated in HIV-infected patients receiving protease inhibitors.

Iatrogenic Cushing's syndrome with osteoporosis and secondary adrenal failure in human immunodeficiency virus-infected patients receiving inhaled corticosteroids and ritonavir-boosted protease inhibitors: six cases

Ritonavir, a protease inhibitor (PI), is a potent inhibitor of cytochrome P450 3A4. This pharmacological effect, even at low doses (</=200 mg/d), is used to "boost" levels of other PIs in the treatment of HIV infection and facilitate once or twice daily dosing with reduced pill burden. Six patients with preexisting HIV-lipodystrophy developed symptomatic Cushing's syndrome when treated with inhaled fluticasone at varying doses for asthma while concurrently treated with low-dose ritonavir-boosted PI antiretroviral therapy (ART) regimens for HIV infection. There was evidence of adrenal suppression in all patients on stimulation studies. After the withdrawal of inhaled fluticasone, four patients became symptomatic of hypocortisolism, and three required oral corticosteroid support for several months. Other complications included evidence of osteoporosis (n = 3), crush fractures (n = 1), and exacerbation of preexisting type 2 diabetes mellitus (n = 1). In part, the diagnosis of fluticasone-induced Cushing's syndrome was delayed because all patients had preexisting body composition changes of ART-associated lipodystrophy, masking the Cushing's features. Practitioners should be aware of the impact on the adrenal axis of coadministration of PI-based ART regimens with inhaled corticosteroids and the potential for exacerbating or even inducing other metabolic conditions, such as osteoporosis or diabetes.

Exogenous Cushing's syndrome and glucocorticoid withdrawal

Glucocorticoid therapy in various forms is extremely common for a wide range of inflammatory, autoimmune, and neoplastic disorders. It is therefore important for the physician to be aware of the possibility of both iatrogenic and factitious Cushing's syndrome. Although most common with oral therapy, it is also important to be alert to the fact that all forms of glucocorticoid delivery have the potential to cause Cushing's syndrome. Withdrawal from chronic glucocorticoid therapy presents significant challenges. These include the possibility of adrenal insufficiency after discontinuation of steroid therapy, recurrence of underlying disease as the glucocorticoid is being withdrawn, and the possibility of steroid withdrawal symptoms. Nonetheless, with patience and persistence, a reasonable approach to withdrawal of glucocorticoid therapy can be achieved.

Quantitative, Highly Sensitive Liquid Chromatography–Tandem Mass Spectrometry Method for Detection of Synthetic Corticosteroids

Background: Measurements of serum or urine concentrations of synthetic glucocorticoids are useful for assessing suspected iatrogenic hypothalamic-pituitary-adrenal axis suppression and Cushing syndrome. We have developed a liquid chromatography–tandem mass spectrometry (LC-MS/MS) assay for the simultaneous quantitative analysis of beclomethasone dipropionate, betamethasone, budesonide, dexamethasone, fludrocortisone, flunisolide, fluorometholone, fluticasone propionate, megestrol acetate, methylprednisolone, prednisolone, prednisone, triamcinolone, and triamcinolone acetonide.

Methods: Stable isotopes of cortisol-9,11,12,12-d4 and triamcinolone-d1 acetonide-d6 were added as internal standards to calibrators, controls, and unknown samples. After acetonitrile precipitation, these samples were extracted with methylene chloride, and the extracts were washed and dried. Reconstituted extract (15 μL) was injected on a reversed-phase column and analyzed by LC-MS/MS in positive-ion mode. Assay precision, accuracy, linearity, and sample stability were determined by use of enriched samples. Clinical validation included analysis of 8 serum and 20 urine samples from patients with undetectable cortisol concentrations and analysis of different types of tablets.

Results: Functional assay sensitivity was as low as 0.6–1.6 nmol/L for all compounds except for triamcinolone (7.6 nmol/L). Interassay CVs were 3.0–20% for concentrations of 0.6–364 nmol/L for all analytes. Recoveries of all analytes (except triamcinolone in serum) were 82–138% at 19.2–693 nmol/L. All but one of the serum and urine samples from patients who were tested because of suppressed cortisol concentrations contained at least one synthetic steroid. Tablet analysis recovered 75% of the synthetic steroids in suspected drugs.

Conclusions: LC-MS/MS allows simultaneous quantitative detection of various synthetic steroids in serum, plasma, urine, and tablets. This provides a valuable tool for evaluating the clinical effects of topical and systemic synthetic corticosteroids.

Antiretrovirals, Part 1: Overview, History, and Focus on Protease Inhibitors

This column is the first in a series on HIV/AIDS antiretroviral drugs. This first review summarizes the history of HIV/AIDS and the development of highly active antiretroviral therapy (HAART) and highlights why it is important for non-HIV specialists to know about these drugs. There are four broad classes of HIV medications used in varying combinations in HAART: the protease inhibitors, nucleoside analogue reverse transcriptase inhibitors, the non-nucleoside reverse transcriptase inhibitors, and cell membrane fusion inhibitors. This paper reviews the mechanism of action, side effects, toxicities, and drug interactions of the protease inhibitors.

A review of low-dose ritonavir in protease inhibitor combination therapy

The pharmacokinetics of protease inhibitors center around the microsomal enzyme cytochrome P-450 3A4. As a potent inhibitor of this enzyme, ritonavir can increase the bioavailability and half-life of coadministered protease inhibitors. Evidence suggests that increased exposure to protease inhibitors is clinically relevant. Antiretroviral treatment with low-dose ritonavir-boosted lopinavir, indinavir, and saquinavir has durable virological activity and shows impressive immune reconstitution. Although tolerable in most cases, gastrointestinal side effects, hepatotoxicity, and blood lipid abnormalities remain relevant issues. Additional study will elucidate the advantages and disadvantages of twice-daily, low-dose ritonavir-boosted regimens and determine whether once-daily regimens based on this principle will have a lasting role in clinical practice.

Adverse skin reactions to inhaled corticosteroids

Inhaled corticosteroids are considered to be the therapy of choice in the treatment of asthma and allergic rhinitis. However, various cutaneous adverse reactions have been described and are probably present in approximately half of patients. Some of these reactions are related to the daily dosage of steroids or the duration of treatment, for example: thinning of the skin, easy bruising, acne or peri-oral dermatitis, mucocutaneous infection and, especially, candidiasis. Other cutaneous side effects are independent of the dose, such as allergic reactions and a few other rare side effects. Adverse effects could be prevented by monitoring the daily dosage and the family history of the patients, and by following advice provided on the use of inhaled corticosteroids. Specific treatments for infection, acne or allergy can cure these side effects. However, cutaneous side effects can become unpleasant for the patient and temporarily withdrawing therapy has proven to be extremely effective.