The Analysis of 124 Cases with Primary Aldosteronism - Evaluation of the Confirmatory Tests and Post Therapeutic Renal Function -

Program: Abstracts - Orals, Featured Poster Presentations, and Posters
Session: MON 723-757-Renin-Angiotensin-Aldosterone System/Endocrine Hypertension
Bench to Bedside
Monday, June 17, 2013: 1:45 PM-3:45 PM
Expo Halls ABC (Moscone Center)

Poster Board MON-733
Takamasa Ichijo*, Eiko Yoshida, Ayumi Yoshifuji, Kaoru Yamashita, Hiromi Ouchi and Mariko Higa
Saiseikai Yokohamashi Tobu Hospital, Yokohama, Japan
It is known that relatively hyperfiltration is observed among the patients with primary aldosteronism (PA) and long-term exposure to excess aldosterone levels, independent of blood pressure (BP), could result in kidney structural damage which may not be fully reserved after treatment. Thus, we evaluate the kidney function after therapy in our series to survey how fast the kidney damage progress and if there is any difference between the adrenalectomy and mineralcorticoid receptor blockers (MRBs) administration.

We screened patients with hypertension and 124 of those showed the aldosterone-renin ratio (ARR) >20, which we considered positive. We, then, performed the confirmatory tests, such as rapid ACTH stimulating, captopril challenge, upright plus furosemide, and saline infusion tests, to those patients to diagnose PA. When any of those confirmatory tests were positive, and when surgical treatment is practicable, the diagnosis unilateral hyperaldosteronism (UHA) or bilateral hyperaldosteronism (BHA) was made by ACTH loading-adrenal venous sampling (ACTH-AVS) after CT scans. We, then, finally perform unilateral laparoscopic adrenalectomy upon AVS documented unilateral hyperaldosteronism. Otherwise, we administrated MRBs, spinorolactone or eplerenone. We then analyzed 54 cases with PA including both APA and suspicious IHA for renal function by eGFR, who were followed at least for 1 year after surgery or MRBs administration.

The mean age was 56.2±13.1 years old including 53 males and 71 females, and the mean ARR was 54.7±82.8. The rapid ACTH test showed the highest sensitivity. Twenty-seven and 59 cases out of 97 AVS performed cases showed UHA and BHA, respectively. Our ACTH-AVS results revealed the mean ARR of UHA was significantly higher than one of BHA, 74.0 ± 90.6 vs. 50.4 ± 56.6, respectively, as we reported. We next analyzed the renal function among 54 patients followed for more than a year after treatment, either adrenalectomy or MRB administration, and the median follow up term was 2 years. The mean eGFR at diagnosis was 78.4±17.9 ml/min/1.73m2, and decreased by -7.8±8.2 ml/min/1.73m2/year. The decrease of eGFR was most significant in the first year and the ratio was -12.0±9.4 ml/min/1.73m2, and the eGFR in second year was interestingly improved by +1.8±6.6 ml/min/1.73m2. We also evaluated the difference of eGFR year-decrease ratios between surgery and MRBs, and they were -8.2±10.5 and -7.6±7.6 ml/min/1.73m2, respectively, and no significance was observed.

In conclusion, our results showed the rapid ACTH test is useful for the confirmatory tests, and either adrenalectomy or MRBs administration showed significant decrease of eGFR after treatment, which ratio is much greater than healthy Japanese, reported -0.36 ml/min/1.73m2/year. Therefore, the early diagnosis and treatment is fundamentally important for PA management.

Nothing to Disclose: TI, EY, AY, KY, HO, MH

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