Iatrogenic Cushing syndrome and secondary adrenal insufficiency related to concomitant triamcinolone and ritonavir administration: a case report and review

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.

Iatrogenic Cushing's Syndrome Following Intra-Articular Triamcinolone Injection in an HIV-Infected Patient on Cobicistat Presenting as a Pulmonary Embolism: Case Report and Literature Review

Background

Iatrogenic Cushing’s syndrome (ICS) typically develops after long-term exposure to corticosteroids, but it can occur after a single dose in patients treated with cobicistat or ritonavir for HIV. We present a patient who developed ICS due to the interaction between cobicistat and triamcinolone, a review of the literature, and what to our knowledge is the first case of ICS presenting as a pulmonary embolism.

Case Presentation

A 55-year old male with a past medical history of human immunodeficiency virus, undetectable for 15 years and currently on elvitegravir/cobicistat/emtricitabine/tenofovir alafenamide, received 2 intra-articular injections of triamcinolone one month apart for a Baker’s cyst in his right knee. He used nasal fluticasone for 9 days in-between the injections. After his second knee injection, he developed easy bruising and friable skin. Over the coming months, he experienced weight gain and Cushingoid facies. Four months after the knee injections he developed a pulmonary embolism and deep vein thrombosis treated with warfarin. The Cushingoid facies prompted an evaluation and diagnosis of ICS along with hypothalamic pituitary adrenal axis suppression.

Conclusion

This case demonstrates the need to monitor patients on pharmacological boosters with any exposure to corticosteroids, whether it be injected, inhaled, topical, oral or intravenous, as it can lead to profound adrenal suppression and ICS.

Adrenal insufficiency due to ritonavir-triamcinolone drug-drug interaction without preceding Cushing's syndrome

We present the case of a 58-year-old HIV-infected patient with adrenal insufficiency after local injection of triamcinolone, most likely due to drug-drug interaction with his ritonavir-boosted antiretroviral therapy (ART). This is the first case of adrenal insufficiency occurring without prior symptoms of Cushing's syndrome in a patient on a booster-containing ART. We want to draw attention to this seemingly rare, but potentially life-threatening medical condition that can occur even in short-term use of glucocorticoids in low doses in patients on booster-containing ART and summarize some considerations for management.

Serum Triamcinolone Levels following Cervical Interlaminar Epidural Injection

Background

Cervical interlaminar epidural steroid injections (ESIs) are commonly performed procedures to treat painful cervical radiculopathy, but little is known about the systemic absorption and serum levels of steroids following injection. The primary objective of this study was to investigate the pharmacokinetics of fluoroscopy-guided cervical epidural-administered triamcinolone acetonide in a cohort of patients with cervical radicular pain seeking treatment in a pain medicine clinic.

Methods

The study cohort included eight patients undergoing a fluoroscopically guided C7-T1 interlaminar ESI at a pain medicine specialty clinic. Blood was collected prior to the ESI and on days 1, 2, 4, 6, 8, 14, 21, 28, 35, and 42 following the injection. The sample extract was analyzed by tandem mass spectrometry.

Results

The terminal elimination half-life of cervical epidural-administered triamcinolone in a noncompartmental analysis was 219 hours. In the noncompartmental analysis, peak triamcinolone concentrations of 5.4 ng/mL were detected within 22.1 hours after administration.

Conclusions

The pharmacokinetics of cervical epidural-administered triamcinolone is consistent with our previous study of lumbar ESI, demonstrating that the elimination half-life is longer than that which has been reported following intravenous triamcinolone. The elimination half-life was shorter following cervical ESI than that which has been reported following lumbar ESI.

Treatment with Synthetic Glucocorticoids and the Hypothalamus-Pituitary-Adrenal Axis

Chronic glucocorticoid (GC) treatment represents a widely-prescribed therapy for several diseases in consideration of both anti-inflammatory and immunosuppressive activity but, if used at high doses for prolonged periods, it can determine the systemic effects characteristic of Cushing's syndrome. In addition to signs and symptoms of hypercortisolism, patients on chronic GC therapy are at risk to develop tertiary adrenal insufficiency after the reduction or the withdrawal of corticosteroids or during acute stress. This effect is mediated by the negative feedback loop on the hypothalamus-pituitary-adrenal (HPA) axis, which mainly involves corticotropin-release hormone (CRH), which represents the most important driver of adrenocorticotropic hormone (ACTH) release. In fact, after withdrawal of chronic GC treatment, reactivation of CRH secretion is a necessary prerequisite for the recovery of the HPA axis. In addition to the well-known factors which regulate the degree of inhibition of the HPA during synthetic GC therapy (type of compound, method of administration, cumulative dose, duration of the treatment, concomitant drugs which can increase the bioavailability of GCs), there is a considerable variation in individual physiology, probably related to different genetic profiles which regulate GC receptor activity. This may represent an interesting basis for possible future research fields.

A review of drug-drug interactions in older HIV-infected patients

INTRODUCTION

The number of older HIV-infected people is growing due to increasing life expectancies resulting from the use of antiretroviral therapy (ART). Both HIV and aging increase the risk of other comorbidities, such as cardiovascular disease, osteoporosis, and some malignancies, leading to greater challenges in managing HIV with other conditions. This results in complex medication regimens with the potential for significant drug-drug interactions and increased morbidity and mortality. Area covered: We review the metabolic pathways of ART and other medications used to treat medical co-morbidities, highlight potential areas of concern for drug-drug interactions, and where feasible, suggest alternative approaches for treating these conditions as suggested from national guidelines or articles published in the English language. Expert commentary: There is limited evidence-based data on ART drug interactions, pharmacokinetics and pharmacodynamics in the older HIV-infected population. Choosing and maintaining effective ART regimens for older adults requires consideration of side effect profile, individual comorbidities, interactions with concurrent prescriptions and non-prescription medications and supplements, dietary patterns with respect to dosing, pill burden and ease of dosing, cost and affordability, patient preferences, social situation, and ART resistance history. Practitioners must remain vigilant for potential drug interactions and intervene when there is a potential for harm.

Aging with HIV in the ART era

In the current era of therapy for human immunodeficiency virus (HIV), life expectancy for persons living with HIV (PLWH) approaches that of the general population. This newly prolonged survival among PLWH is associated with an increased prevalence of comorbidities due to the inflammation, immune activation and immune senescence associated with HIV infection. Higher prevalence of tobacco and alcohol use, co-infection with viral hepatitis and traditional cardiovascular risk factors such as hypertension and hyperlipidemia contribute as well. In this review, we hope to describe the current comorbidities occurring among PLWH and bring increased awareness for conditions that may otherwise not be considered given the younger age at time of presentation.

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.

Current state and limitations of daily oral therapy for treatment

PURPOSE OF REVIEW

We aim to review the strengths and weaknesses of current antiretroviral therapy (ART), and describe ongoing research to address limitations to current therapy.

RECENT FINDINGS

Current ART is highly effective and well tolerated. As a result of a decrease in medication side-effects and pill burden, and the known health effects of uncontrolled viremia, ART is now recommended at all CD4 cell counts in the USA. Novel medications are being developed to further decrease side-effects and offer alternative options for patients with multiclass resistance. New combination pills will further decrease pill burden.

SUMMARY

Current treatment for HIV is characterized by highly potent oral antiretroviral medications, which are well tolerated, resulting in outstanding rates of virologic suppression in patients who are adherent to therapy. Despite the marked improvement in therapeutic options, limitations to therapy still exist including reliance on daily adherence, long-term toxicity of medications, drug-drug interactions, long-term effects of HIV even in the setting of viral suppression, high lifetime cost of treatment, and limited options for some patients with multiclass resistance. Emerging alternative treatment strategies include nucleoside reverse transcriptase inhibitor-sparing or limiting regimens and long-acting injectable combination therapy.

A Review of the Toxicity of HIV Medications II: Interactions with Drugs and Complementary and Alternative Medicine Products

For many patients today, HIV has become a chronic disease. For those patients who have access to and adhere to lifelong antiretroviral (ARV) therapy, the potential for drug-drug interactions has become a real and life-threatening concern. It is known that most ARV drug interactions occur through the cytochrome P450 (CYP) pathway. Medications for comorbid medical conditions, holistic supplements, and illicit drugs can be affected by CYP inhibitors and inducers and have the potential to cause harm and toxicity. Protease inhibitors (PIs) tend to inhibit CYP3A4, while most non-nucleoside reverse transcriptase inhibitors (NNRTIs) tend to induce the enzyme. As such, failure to adjust the dose of co-administered medications, such as statins and steroids, may lead to serious complications including rhabdomyolysis and hypercortisolism, respectively. Similarly, gastric acid blockers can decrease several ARV absorption, and warfarin doses may need to be adjusted to maintain therapeutic concentrations. Illicit drugs such as methylenedioxymethamphetamine (MDMA, "ecstasy") in combination with PIs lead to increased toxicity, while the concomitant administration of sedative drugs such as midazolam and alprazolam in patients taking PIs can result in prolonged sedation, delayed recovery, and increased length of stay. Even supplements like St. John's Wort can alter PI concentrations. In theory, any drug that is metabolized by CYP has potential for a pharmacokinetic drug-drug interaction with all PIs, cobicistat, and most NNRTIs. When adding a new medication to an ARV regimen, use of a drug-drug interaction software and/or consultation with a clinical pharmacist/pharmacologist or HIV specialist is recommended.