MAGNITUDE AND DURATION OF HYPOTHALAMIC-PITUITARY-ADRENAL (HPA) AXIS' SUPPRESSION FOLLOWING AN INTRA-BURSAL INJECTION OF METILPREDNISOLONE ACETATE COMPARED TO TRIAMCINOLONE ACETILATE

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: SUN 50-71-HPA Axis
Clinical
Sunday, June 16, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board SUN-65
Federica Guaraldi*1, Milva Battaglia2, Emanuela Castiello2, Marta Leporati3, Davide Gori4, Silvia Grottoli1, Fabio Settanni1, Alessandra Sudanese2, Ezio G G M Ghigo1 and Emanuela Arvat1
1University of Turin, Turin, Italy, 2Rizzoli Orthopaedic Institute, Bologna, Italy, 3Centro Regionale Antidoping "A. Bertinaria", Orbassano (Turin), Italy, 4School of Hygiene and Preventive Medicine, Bologna, Italy
Introduction

Systemic and intra-articular corticosteroids are the gold standard treatment to relieve pain and inflammation associated to various articular disorders and orthopedic procedures. At the same time, HPA axis’ suppression is a major side effect associated to these therapies. We provide data of the first study assessing the magnitude and duration of HPA axis’ suppression following a single intra-bursal injection of two different steroids in a large, homogeneous cohort of patients, evaluated using new techniques for hormonal assays.

Materials and methods

Randomized, blind, case-control study. 40 patients affected by rotator cuff painful calcific tendonitis underwent percutaneous ultrasound-guided treatment (TPE). They were then randomly treated with an intra-bursal injection of 40 mg of metilprednisolone acetate (MA) (group A, 20 patients) or triamcinolone acetonide (TA) (group B, 20 patients). Exclusion criteria were steroid/ACTH treatment in the previous 3 months, pregnancy, lactation and severe concomitant diseases. In all patients, the morning before (T0) and 1 (T1), 7 (T2), 15 (T3), 30 (T4) and 45 (T5) days after treatment we evaluated plasmatic cortisol and ACTH (by RIA), urinary cortisol, urinary MA/TA (by LC-MS/MC).

Results: At baseline, levels of plasmatic cortisol and ACTH, and urinary cortisol were in the normal range and similar in both groups. Compared to T0, a significant (p<0.00001) and similar decrease  in levels (mean ± SD, mean difference 95% CI) of plasmatic ACTH (Group A 9.1 ± 9.1 vs 23.77 ± 11.29; 15±7 pg/ml. Group B 5.49 ± 6.96 vs 29.2 ± 16.14; 24±8 pg/ml) and cortisol (Group A 45.94 ± 50.66 vs 182.55 ± 59.67; 136±36 ng/ml. Group B 36.97 ± 52.9 vs 179.71 ± 58.41; 143±35 ng/ml) and urinary cortisol (Group A 7.23±8.1 vs ±24±11; -16.77 ±5.57 µg/die. Group B 12.83±20.88 vs 24±9; -11.17 ±8.27 µg/die) was observed at T1 in both groups (mean hormonal levels under minimal reference value in >85% of patients). Compared to baseline, no significant differences (p>0.05) were found for mean ACTH levels after T2; cortisol levels were similar to baseline after T2 in group A, and after T3 in group B, whereas mean urinary cortisol levels were still significantly (p<0.001) lower up to T4 in group B (13.88±8.79; -10.12±5.79 mcg/die) and up to T5 in group A (14.01±10.15; -9.99±5.9 mcg/die). Drugs’ urinary levels decreased sharply from T1 to T2 (MA: 23.15±14.51 vs 5.37±4.38 ng/ml. TA: 12.33 ± 7.53 vs 4.56 ± 3.08 ng/ml) and then more gradually disappeared, being still detectable in ~10% of the patients at T5.     

Conclusions: a single intra-bursal injection of 40 mg of MA/TA is sufficient to temporarily (up to 45 days) suppress HPA axis’ function, with no significant differences between the two drugs, and a trend of cortisol production converse but parallel to drug elimination. For this reason, treated patients deserve a particular attention and replacement therapy, especially under stress conditions.

Nothing to Disclose: FG, MB, EC, ML, DG, SG, FS, AS, EGGMG, EA

*Please take note of The Endocrine Society's News Embargo Policy at http://www.endo-society.org/endo2013/media.cfm