Severe Posaconazole-Induced Glucocorticoid Deficiency with Concurrent Pseudohyperaldosteronism: An Unfortunate Two-for-One Special

Posaconazole-induced primary adrenal insufficiency: A rare but real risk

Primary adrenal insufficiency (PAI) consists in a lack of adrenal hormones, and particularly of cortisol and aldosterone. It typically presents with fatigue, weakness, loss of appetite, increased thirst and skin hyperpigmentation. While most cases stem from an autoimmune etiology, rare instances of PAI have been attributed to infection, adrenal hemorrhage and medication disrupting steroidogenesis pathways. This report presents two patients with hematologic malignancies who developed primary glucocorticoid deficiency due to posaconazole. Both received allogeneic stem-cell transplantation and used posaconazole as antifungal prophylaxis. Both patients had low morning cortisol and elevated ACTH levels, which suggested primary adrenal insufficiency. Posaconazole, widely used for antifungal prophylaxis and long-term therapy, undoubtedly affects adrenal steroid synthesis. Thus, healthcare providers must be aware of that posaconazole may cause adrenal insufficiency, and should monitor patients taking this medication.

Characterization of the interferences of systemic azole antifungal drugs with adrenal steroid biosynthesis using H295R cells and enzyme activity assays

Azole antifungals, designed to inhibit fungal CYP51, have a liability to inhibit human CYP enzymes. Whilst drug-metabolizing CYPs are covered in preclinical safety assessment, those metabolizing endogenous bioactive molecules are usually not. Posaconazole and itraconazole were recently found to cause pseudohyperaldosteronism with hypokalemia and hypertension by inhibiting CYP11B1-dependent adrenal cortisol biosynthesis. Because this was overlooked in preclinical safety assessment, the present study tested whether applying adrenal carcinoma H295R cells could have predicted this liability and whether other systemic triazole antifungals interfere with adrenal steroidogenesis. Forskolin-stimulated H295R cells were exposed to systemic triazole antifungals that are currently used, and key adrenal steroids were quantified by UHPLC-MS/MS. To support the findings from the H295R model, activity assays for steroidogenic enzymes were performed. The analysis of the steroid profiles and product/substrate ratios predicted the CYP11B1 and CYP11B2 inhibition by posaconazole and itraconazole. Comparison of their steroid profiles allowed distinguishing their effects and suggested inhibition of adrenal androgen synthesis by posaconazole but not itraconazole, which was confirmed by CYP17A1 17,20-lyase activity measurements. In line with clinical observations, there was no evidence from these experiments for an inhibition of either CYP11B1/2 or CYP17A1 by voriconazole, fluconazole or isavuconazole. However, itraconazole and isavuconazole exerted an overall inhibition of steroidogenesis by a mechanism warranting further investigations. In conclusion, analyses of steroid profiles from the H295R assay and product/substrate ratios provide important information on the interference of a chemical with adrenal steroidogenesis and the underlying mechanism. This approach facilitates prioritization of further investigations, including enzyme expression and activity studies.

Case Report: Hypercalcemia as a manifestation of acute adrenal crisis precipitated by fluconazole use, and a review of the literature

Acute adrenal crisis classically presents with vomiting, altered sensorium, and hypotension. We describe a unique case manifesting with severe hypercalcemia. Addisonian crisis was unusually precipitated by fluconazole use. We reviewed other reported cases and discuss the possible mechanisms of hypercalcemia in adrenal insufficiency. This 67-year-old man presented with fever, cough, and vomiting for 1 week and with anorexia and confusion for 3 weeks. He was hypotensive and clinically dehydrated. Investigations revealed left-sided lung consolidation, acute renal failure, and severe non-parathyroid hormone (PTH)-mediated hypercalcemia (calcium, 3.55mol/L; PTH, 0.81pmol/L). Initial impression was pneumonia complicated by septic shock and hypercalcemia secondary to possible malignancy. He received mechanical ventilation; treatment with intravenous fluids, inotropes, and hydrocortisone for septic shock; and continuous renal replacement therapy with low-calcium dialysate. Although hypercalcemia resolved and he was weaned off inotropes, dialysis, and hydrocortisone, his confusion persisted. When hypercalcemia recurred on day 19 of admission, early morning cortisol was <8 nmol/L, with low ACTH level (3.2 ng/L). Other pituitary hormones were normal. Hypercalcemia resolved 3 days after reinstating stress doses of hydrocortisone, and his mentation normalized. On further questioning, he recently received fluconazole for a forearm abscess. He previously consumed traditional medications but stopped several years ago, which may have contained glucocorticoids. He was discharged on oral hydrocortisone. Cortisol levels improved gradually, and glucocorticoid replacement was ceased after 8 years, without any recurrence of hypercalcemia or Addisonian crisis. Both hypercalcemia and adrenal insufficiency may present with similar non-specific symptoms. It is important to consider adrenal insufficiency in hypercalcemia of unclear etiology.