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

Metabolomics studies in cushing's syndrome: recent developments and perspectives

INTRODUCTION

Exogenous Cushing's syndrome is the result of long-term exposure to glucocorticoids, while endogenous Cushing's syndrome occurs due to excessive production of glucocorticoids within the body. Cushing's syndrome remains a diagnostic challenge for the treating physician.Mass spectrometry, with its better resolution, detectability, and specificity, paved the way to understanding the cellular and molecular mechanisms involved in several diseases that facilitated the evolution of biomarkers and personalized medicine, which can be applicable to manage Cushing's syndrome as well.

AREAS COVERED

There are only a few reports of mass spectrometry-based metabolomic approaches to endogenous Cushing's syndrome of certain etiologies. However, the application of this approach in the diagnosis of exogenous Cushing has not been explored much. This review attempts to discuss the application of the mass spectrometry-based metabolomic approach in the evaluation of Cushing's syndrome.

EXPERT OPINION

Global metabolomics has the potential to discover altered metabolites and associated signaling and metabolic pathways, which may serve as potential biomarkers that would help in developing tools to accelerate precision medicine. Multi-omics approaches will provide innovative solutions to develop molecular tests for multi-molecule panel assays.

Drug-Drug Interactions With Over-The-Counter Medicines: Mind the Unprescribed

BACKGROUND

This review provides a summary of the currently available clinical data on drug-drug interactions (DDIs) involving over-the-counter (OTC) medicines. It aims to educate and increase awareness among health care providers and to support decisions in daily practice.

METHODS

An extensive literature search was performed using bibliographic databases available through PubMed.gov. An initial structured search was performed using the keywords "drug-drug-interaction AND (over-the-counter OR OTC)," without further restrictions except for the language. The initial results were screened for all described DDIs involving OTC drugs, and further information was gathered specifically on these drugs using dedicated database searches and references found in the bibliography from the initial hits.

RESULTS

From more than 1200 initial hits (1972-June 2021), 408 relevant publications were screened for DDIs involving OTC drugs, leading to 2 major findings: first, certain types of drug regimens are more prone to DDIs or have more serious DDI-related consequences, such as antiretroviral, anti-infective, and oral anticancer therapies. Second, although most DDIs involve OTC drugs as the perpetrators, some prescription drugs (statins or phosphodiesterase-5 inhibitors) that currently have OTC status can be identified as the victims in DDIs. The following groups were identified to be frequently involved in DDIs: nonsteroidal anti-inflammatory drugs, food supplements, antacids, proton-pump inhibitors, H2 antihistamines, laxatives, antidiarrheal drugs, and herbal drugs.

CONCLUSIONS

The most significant finding was the lack of high-quality evidence for commonly acknowledged interactions. High-quality interaction studies involving different phenotypes in drug metabolism (cytochrome P450) and distribution (transporters) are urgently needed. This should include modern and critical drugs, such as oral anticancer medications and direct oral anticoagulants.

Iatrogenic Cushing's syndrome due to drug interaction between glucocorticoids and the ritonavir or cobicistat containing HIV therapies

Ritonavir and cobicistat, used as pharmacokinetic enhancers in combination with some antiretrovirals (ARVs) for the treatment of HIV, are potent inhibitors of the CYP3A4 isoenzyme. Most glucocorticoids are metabolised via the CYP3A4 pathway and iatrogenic Cushing's syndrome (ICS), with possible secondary adrenal insufficiency (SAI), is a recognised complication following co-administration with ritonavir or cobicistat. A structured approach for identifying and managing potentially affected individuals has not been established.We systematically identified patients with ICS/SAI and found substantial heterogeneity in clinical practice across three large London HIV centres. While this significant drug interaction and its complications are now well-recognised, it is apparent that there is no standardised approach to management or guidance for the general physician. Here we describe the management of ICS/SAI in our current practice, review the available evidence and suggest practice recommendations.

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.

Endocrinopathies in children infected with human immunodeficiency virus

Endocrine changes (including adrenal insufficiency, disorders of growth and puberty, thyroid dysfunction, metabolic abnormalities and osteopenia) accompany human immunodeficiency virus (HIV) infection in pediatric patients. The cause of these changes is multifactorial and includes direct viral effects of HIV, and effects of antiretroviral therapy. These effects may be of particular importance in childhood given the critical developmental processes that occur during this time period and the likelihood of prolonged exposure to the virus and medications.

Metabolic considerations of drugs in the treatment of allergic diseases

INTRODUCTION

The clinical management of allergic diseases involves a number of drugs, most of which are extensively metabolized. This review aims to analyze the metabolism and the clinical implications of altered metabolism for these drugs.

AREAS COVERED

The authors present an overview of current knowledge of the metabolism of: antihistamine drugs, glucocorticoids, inhaled β-2 bronchodilators, anticholinergics and other drugs used in allergic diseases, such as cromoglycate, omalizumab, montelukast and epinephrine. Polymorphic drug metabolism is relevant for chlorpheniramine, loratadine and montelukast. Inhibition of drug metabolism is relevant for loratadine, methylprednisolone, fluticasone, mometasone, triamcinolone or prednisolone. Polymorphic pre-systemic metabolism may be relevant to budesonide, fluticasone, beclomethasone, mometasone or salmeterol. The authors also discuss the current information on gene variations according to the 1,000 genomes catalog and other databases. Finally, the authors review the clinical implications of these variations with a particular regard to drugs used in the management of allergic diseases.

EXPERT OPINION

Most drugs used in allergic diseases are extensively metabolized. Drug interaction or adverse reactions related to altered metabolism are relevant issues that should be considered in the management of allergic diseases. However, much additional research is required before defining pharmacogenomic biomarkers for the management of drugs used in allergic diseases.

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.

[AIDS Study Group/Spanish AIDS Plan consensus document on antiretroviral therapy in adults with human immunodeficiency virus infection (updated January 2010)]

OBJECTIVE

This consensus document is an update of antiretroviral therapy recommendations for adult patients with human immunodeficiency virus infection.

METHODS

To formulate these recommendations a panel made up of members of the Grupo de Estudio de Sida (Gesida, AIDS Study Group) and the Plan Nacional sobre el Sida (PNS, Spanish AIDS Plan) reviewed the advances in the current understanding of the pathophysiology of human immunodeficiency virus (HIV) infection, the efficacy and safety of clinical trials, and cohort and pharmacokinetic studies published in biomedical journals or presented at scientific meetings. Three levels of evidence were defined according to the data source: randomized studies (level A), cohort or case-control studies (level B), and expert opinion (level C). The decision to recommend, consider or not to recommend ART was established in each situation.

RESULTS

Currently, the treatment of choice for chronic HIV infection is the combination of three drugs of two different classes, including 2 nucleosides or nucleotide analogs (NRTI) plus 1 non-nucleoside (NNRTI) or 1 boosted protease inhibitor (PI/r), but other combinations are possible. Initiation of ART is recommended in patients with symptomatic HIV infection. In asymptomatic patients, initiation of ART is recommended on the basis of CD4 lymphocyte counts, plasma viral load and patient co-morbidities, as follows: 1) therapy should be started in patients with CD4 counts below 350 cells/microl; 2) When CD4 counts are between 350 and 500 cells/microl, therapy should be started in case of cirrhosis, chronic hepatitis C, high cardiovascular risk, HIV nephropathy, HIV viral load above 100,000 copies/ml, proportion of CD4 cells under 14%, and in people aged over 55; 3) Therapy should be deferred when CD4 are above 500 cells/microl, but could be considered if any of previous considerations concurs. Treatment should be initiated in case of hepatitis B requiring treatment and should be considered for reduce sexual transmission. The objective of ART is to achieve an undetectable viral load. Adherence to therapy plays an essential role in maintaining antiviral response. Therapeutic options are limited after ART failures but undetectable viral loads maybe possible with the new drugs even in highly drug experienced patients. Genotype studies are useful in these situations. Drug toxicity of ART therapy is losing importance as benefits exceed adverse effects. Criteria for antiretroviral treatment in acute infection, pregnancy and post-exposure prophylaxis are mentioned as well as the management of HIV co-infection with hepatitis B or C.

CONCLUSIONS

CD4 cells counts, viral load and patient co-morbidities are the most important reference factors to consider when initiating ART in asymptomatic patients. The large number of available drugs, the increased sensitivity of tests to monitor viral load, and the ability to determine viral resistance is leading to a more individualized therapy approach in order to achieve undetectable viral load under any circumstances.

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.