Abstract: PUB541
Two Pearls in an Oyster: Thrombotic Microangiopathy due to Malignant Hypertension from Apparent Mineralocorticoid Excess in a Cushing Syndrome Patient with Primary Bilateral Macronodular Adrenal Hyperplasia
Session Information
Category: Trainee Case Report
- 1002 Genetic Diseases of the Kidneys: Non-Cystic
Authors
- Regis, Catarina, University of Miami, Miami, Florida, United States
- Munoz Mendoza, Jair, University of Miami, Miami, Florida, United States
Group or Team Name
- Katz Family Division of Nephrology at University of Miami
Introduction
Malignant hypertension (HTN) is characterized by severe HTN and target organ damage and can rarely cause thrombotic microangiopathy (TMA). Primary bilateral macronodular adrenal hyperplasia(PBMAH) causes Cushing’s syndrome in less than 2% of the cases, leading to difficult to control HTN. We report this unique case of a patient with malignant HTN and TMA due to apparent mineralocorticoid excess from PBMAH.
Case Description
47 year-old male, with malignant HTN for two years, uncontrolled on four antihypertensives (including diuretics) presented with fatigue, muscle weakness and unintentional weight gain (45 lbs). Physical exam remarkable for BP:160/100; weight 172lbs, moon face, central obesity with buffalo hump, supraclavicular and dorsocervical fat pads and purple abdominal striaes, proximal muscle weakness and thin/scaly skin. Primary Cushing's syndrome was suspected and confirmed with high free AM cortisol at 37mcg/dL, low ACTH at <5 p/mL.
CT abdomen revealed bilateral adrenal adenomas. Further work up: microscopic hematuria and sub-nephrotic proteinuria (1.8g/24hs), Cr 1.2mg/dL. Kidney biopsy: intracapillary thrombi; marked podocyte hypertrophy, consistent with TMA. An extensive workup ruled out the most common causes of TMA like TTP, HUS and complement deficiency. On further tests, he was diagnosed with apparent mineralocorticoid excess through the high 24h urine free cortisol/ free cortisone ratio. A bilateral adrenalectomy was performed to treat the disease and at 12-month follow up visit, BP was controlled (110/70) only on Lisinopril 10mg/day and he had lost 48lbs. Proteinuria: 203 mg/24hs
Discussion
PBMAH causes Cushing’s syndrome in less than 2% of cases. This patient also had TMA present, likely from two pathways:
1. Cushing's syndrome as a hypercoagulable state ( high factor VIII levels, decreased fibrinolysis, and abnormal Von Willebrand factor)
2. Malignant HTN causing endothelial dysfunction and thrombi formation.
Malignant HTN was secondary to the apparent mineralocorticoid excess from PBMAH. Both HTN and Cushing’s syndrome resolved after bilateral adrenalectomy.
PBMAH is a rare cause of Cushing’s syndrome and, to the best of our knowledge, this is the first case of this condition causing apparent mineralocorticoid excess leading to HTN and TMA.