Melanie Philippon

Ketoconazole in Cushing's Disease: Is It Worth a Try?

BACKGROUND The use of ketoconazole has been recently questioned after warnings from the European Medicine Agencies and the Food and Drug Administration due to potential hepatotoxicity. However, ketoconazole is frequently used as a drug to lower circulating cortisol levels. Several pharmacological agents have recently been approved for the treatment of Cushings disease (CD) despite limited efficacy or significant side effects. Ketoconazole has been used worldwide for more than 30 years in CD, but in the absence of a large-scale study, its efficacy and tolerance are still under debate. PATIENTS AND METHODS We conducted a French retrospective multicenter study reviewing data from patients treated by ketoconazole as a single agent for CD, with the aim of clarifying efficacy and tolerance to better determine the benefit/risk balance. RESULTS Data from 200 patients were included in this study. At the last follow-up, 49.3% of patients had normal urinary free cortisol (UFC) levels, 25.6% had at least a 50% decrease, and 25.4% had unchanged UFC levels. The median final dose of ketoconazole was 600 mg/d. Forty patients (20%) received ketoconazole as a presurgical treatment; 40% to 50% of these patients showed improvement of hypertension, hypokalemia, and diabetes, and 48.7% had normal UFC before surgery. Overall, 41 patients (20.5%) stopped the treatment due to poor tolerance. Mild (<5N, inferior to 5-fold normal values) and major (>5N, superior to 5-fold normal values) increases in liver enzymes were observed in 13.5% and 2.5% of patients, respectively. No fatal hepatitis was observed. CONCLUSIONS Ketoconazole is an effective drug with acceptable side effects. It should be used under close liver enzyme monitoring. Hepatotoxicity is usually mild and resolves after drug withdrawal.

Preoperative imaging for focused parathyroidectomy: making a good strategy even better

OBJECTIVE Surgical treatment for primary hyperparathyroidism (pHPT) has undergone a major paradigm shift during the last decades from bilateral cervicotomy with four-gland neck exploration to image-guided focused approaches. The primary objective of the present study was to compare the performances of parathyroid scintigraphy (PS), parathyroid ultrasonography (US), and the combination of both procedures for guiding a focused approach on the basis of modified interpretation criteria. METHODS Data from 199 patients operated for apparent sporadic pHPT and evaluated with US and PS using dual-isotope (123)I/(99m)Tc-sestamibi planar pinhole and single-photon emission computed tomography (SPECT) acqusitions were evaluated. RESULTS A total of 127 patients underwent a focused approach and the remainder had bilateral cervicotomy. In 42 cases, a focused approach was not performed due to the absence of concordant results between US and PS for a single-gland abnormality. Four patients had persistent disease and three had recurrent disease. A localizing preoperative PS had a sensitivity of 93.3%, positive predictive value of 85.8%, negative predictive value of 73.0%, and accuracy of 83.4% for predicting uniglandular disease. Additional SPECT images accurately localize posterior adenomas that are often missed by US. Compared with PS, US had a lower sensitivity (P<0.01). Our imaging protocol also enabled diagnosis of multiglandular disease in 60.6%. CONCLUSIONS PS using a highly sensitive dual-tracer subtraction method is the most accurate technique for directing a focused approach. PS could be sufficient for directing a focused approach in the presence of a negative US in two major circumstances: posterior locations due to acquired ectopia that could be missed by US, and previous history of thyroidectomy due to interpretation difficulties.

Bilateral neck exploration in patients with primary hyperparathyroidism and discordant imaging results: a single-centre study

INTRODUCTION Focused parathyroidectomy is the treatment of choice for patients with concordant positive imaging. Bilateral cervical exploration is performed for cases with discordant imaging, yet more than 70% of those cases are the result of a single-gland disease. As focused parathyroidectomy is generally costless and harmless, for cases with discordant imaging, we tried to determine whether preoperative characteristics can lead to a diagnosis of single-gland disease. METHODS This study included 182 patients treated for primary hyperparathyroidism by bilateral exploration from 2009 to 2012 at La Timone Hospital, Marseille, France. We classified patients based on preoperative images and pathological results (single-gland or multiglandular disease). We then compared the demographical, laboratory and imaging results. We also asked a senior nuclear medicine practitioner who was blind to the ultrasound and pathological results to perform a second reading. RESULTS Of the total number of patients, 15.4% had negative, 54.4% discordant and 30.2% concordant imaging. After reviewing the scintigraphy results, 8% of the cases with discordant imaging would have been classified as concordant with ultrasound. Subtraction scintigraphy obtained better results than dual-phase scintigraphy (concordance with ultrasound in 50 vs 31% with classical scintigraphy). For the cases of discordant imaging, no predictive factors of single-gland disease could be identified. Ultrasound and scintigraphy were similarly effective in determining the correct location of the abnormal gland. CONCLUSION Discordant results of preoperative imaging modalities do not discriminate between uniglandular and multiglandular diseases in hyperparathyroidism. Diagnostic differentiation between the different causes of hyperparathyroidism requires improvements in imaging techniques and might benefit from subtraction scintigraphy.

Heterozygous LHX3 mutations may lead to a mild phenotype of combined pituitary hormone deficiency

LHX3 is an LIM domain transcription factor involved in the early steps of pituitary ontogenesis. We report here functional studies of three allelic variants, including the first heterozygous variant of LHX3 NM_178138.5(LHX3):c.587T>C (p.(Leu196Pro)) that may be responsible for a milder phenotype of hypopituitarism. Our functional studies showed that NM_178138.5(LHX3):c.587T>C (p.(Leu196Pro)) was not able to activate target promoters in vitro, as it did not bind DNA, and likely affected LHX3 function via a mechanism of haplo-insufficiency. Our study demonstrates the possibility that patients with a heterozygous variant of LHX3 may have pituitary deficiencies, with a milder phenotype than patients with homozygous variants. It is thus of vital to propose an optimal follow-up of such patients, who, until now, were considered as not being at risk of presenting pituitary deficiency. The second variant NM_178138.5(LHX3):c.622C>G (p.(Arg208Gly)), present in a homozygous state, displayed decreased transactivating ability without loss of binding capacity in vitro, concordant with in silico analysis; it should thus be considered to affect LHX3 function. In contrast, the NM_178138.5(LHX3):c.929G>C (p.(Arg310Pro)) variant, in a heterozygous state, also predicted as deleterious in silico, proved functionally active in vitro, and should thus still be classified as a variant of unknown significance. Our study emphasizes the need for functional studies due to the limits of software-based predictions of new variants, and the possible association of a pituitary phenotype to heterozygous LHX3 variants.