Aldosteronism atau Conn’s syndrome

Clinical
Primary aldosteronism (Conn’s syndrome) is secondary to either an aldosterone-secreting neoplasm or adrenal hyperplasia. Over half of
primary aldosteronism is due to a functioning adrenocorticoid adenoma (aldosteronoma). Hyperplasia, usually bilateral, accounts for most of the rest, with a carcinoma being rare. Bilateral adenomas have been reported. Some patients with Conn’s syndrome have grossly normal-appearing glands. A pheochromocytoma and primary hyperaldosteronism have occurred simultaneously; whether this is a coincidence or an unknown interreaction is conjecture.
The mineralocorticoid aldosterone is involved in blood volume and serum potassium homeostasis,which in turn regulate aldosterone secretion by the zona glomerulosa in the adrenal cortex. Excessive secretion leads to  hypertension, hypokalemia, and suppression of plasma renin activity, a condition also known as
mineralocorticoid hypertension. This is not a simple condition; although in most patients the two stimuli for aldosterone production (potassium and angiotensin II) tend to be low, some patients have normal serum potassium levels. Familial hyperaldosteronism is described. A curious sideshow is pseudohypermineralocorticism, caused by an excess of mineralotropics other than aldosterone.
Although mineralocorticoid hypertension is not common, its significance lies in its being a potentially correctable cause of high blood pressure. One should keep in mind that aldosteronism also develops in primary renovascular hypertension but the latter entity is associated with high serum renin levels while in primary aldosteronism the renin levels are low. Hypoaldosteronism is rare. It appears to be due to inadequate stimulation of aldosterone secretion or a defect in the adrenal synthesis of aldosterone. An unusual cause of secondary hypoaldosteronism (called pseudohypoaldosteronism by some) is seen in some infants with urinary tract infection, with or without urinary tract obstruction. Clinically, hypoaldosteronism results in hypotension and hyperkalemia. Imaging has no role in its diagnosis.
Imaging A distinction between unilateral aldosteronomas, which are treated surgically, and bilateral hyperplasia, treated medically, is of obvious importance. The adrenal glands are significantly larger in patients with bilateral adrenal hyperplasia than in those with an aldosteronoma. One study achieved 100% sensitivity when a CT mean limb width of >3mm was used to diagnose bilateral adrenal hyperplasia, and 100% specificity when limb width was 5mm or greater. Unless imaging identifies a tumor, such differentiation is generally sought by bilateral adrenal venous sampling.
Aldosteronomas tend to be small; discrete nodules are difficult to visualize. Thus among 18 aldosterone-producing adrenal adenomas, 89% were detected with CT but only 28% with US. Adrenal hyperplasia in Conn’s syndrome ranges from diffuse and bilateral to nodular. Thus one or more nodule may represent either an adenoma or nodular hyperplasia. Complicating this picture is the presence of the occasional unrelated incidental adrenal tumor. Similar to Cushing adenomas, aldosteronomas contain varying amounts of lipid. As a result, some have CT attenuation values close to that of water and their CT appearance can mimic a cyst.
Calcifications develop only in an occasional benign aldosteronoma.
In 20 patients with primary hyperaldosteronism, 50% had aldosterone-producing adenomas and 50% bilateral adrenal hyperplasia; MRI detected adenomas with a sensitivity of 70% and specificity of 100%, with adenomas being iso- to hypointense relative to liver on T1- and slightly hyperintense on T2-weighted images. Of interest is that signal intensity decreased on out-of-phase chemical shift
images in 86% of adenomas and 89% of adrenal hyperplasia, indicating the presence of lipid. Iodine-131–NP-59 scintigraphy appears to be complementary to CT and MR in differentiating between adenomas and adrenal hyperplasia, being especially useful with a unilateral hyperplastic nodule. Scintigraphy visualizes these tumors as hot nodules,with an occasional warm nodule.
Bilateral adrenal venous sampling distinguishes most but not all adenomas from hyperplasia. Blood samples are obtained after stimulation with ACTH. With bilateral hyperplasia, after stimulation aldosterone levels increase in blood samples from both adrenals; on the other hand, a more marked unilateral increase is detected with an aldosteronoma.
image
Radiology images of the Conn’s syndrome. Computed tomography (CT) reveals bilateral adrenal hyperplasia.

Therapy Patients with bilateral glomerulosa hyperplasia and those amenable to glucocorticoid therapy are treated medically. Adenomas are resected, but keep in mind that hypertension persists in 30% to 50% of patients after resection even if they are biochemically cured. Such persistent postoperative hypertension suggests coexisting essential hypertension. Several patients with Conn syndrome and Cushing’s syndrome have been treated by CTguided acetic acid injected into their adrenal nodules; follow-up revealed cystic degeneration. A few aldosteronomas have also been treated by transcatheter arterial embolization with absolute ethanol.

Artikel Terkait

Aldosteronism atau Conn’s syndrome
4/ 5
Oleh

Berlangganan

Suka dengan artikel di atas? Silakan berlangganan gratis via email

This below all content of radiology information

Neuroradiology Musculoskeletal radiology MRI Musculoskeletal MRI Abnormal Mri Brain X-RAY differential diagnosis Head Neck Anatomy mnemonic CT Teleradiology Radiology News chest Radiology musculoskeletal salary pediatrics ultrasound ultrasound images job Brain tumour abdomen interventional radiology CT Abdomen with contrast DAMS Imaging Apk Android radiology ramblings residency c nature pediatric radiology random ramblings xray C T Radiology Top basics body imaging guide procedure web 2.0 Chest X Ray Interpretation Teleradiology Providers head and neck radiology video Fun b cancer chest radiology salary 1 CXR GenitoUrinary ORTHOPEDICS Sonographic Measurements Stroke Ultrasound Hepatitis dams md/ms coaching mammography radiology business tuberculosis BRAIN Clinicoradiological series FETUS GI radiology Gastrointestinal x ray Radiology 4 Radiology Conferences Radiology Images Telemedicine UPPER LIMPS Ultrasound in Emergencies dynamic MRI lifestyle radiology links renal case spine 3 tesla MRI Dams clinicoradiological series Entrepreneur Gastrointestinal Tract Images Literature Liver abscess ultrasound MD/MS coaching Radiology 40 Radiology Imaging Radiology Journal Radiology PDF Radiology mcqs Ultrasound Technique blog bone tumour cardiac CT career cerebral venous thrombosis chest xray d fracture gadolinium gastrointestinal genitourinary radiology hepatobiliary imaging lipoma medical blogs mri lower abdomen pelvis psychiatry radiation concern social networking technology training urogenital imaging weblog 3D CT Arachnoid cyst CT Cardiac Chest X Ray Diploma Guid Equipment Cost FDA Fibrous dysplasia Interventional Ultrasound Guiding Biopsi MDCT MR Pancreas MRI Vertebrae MRI Vertebrae lumbal MRI contrast MRS RTA Radiology Teaching resource TB Hip TECHNIQUE Tech Thorax X Ray Upper Ext aiims ankle sprain bowel cancer brain abscess case study computers and radiology contrast ependymoma epidermoid facebook guest post internet journal of radiology iphone kienbock disease liver liver segments ct locum tenens mri abdomen multislice CT pericallosal lipoma plain film teaching files private practice radiology humour shoulder arthrogram shoulder dislocation small bowel social media trigeminal neuralgia tuberous sclerosis venous x ray Vertebrae 3d printing 7 tesla MRI ACL reconstruction ACL tear ACLS AIIMS nov 2008 ALPSA lesion ANGIOGRAPHY ATFL B12 deficiency BLS BOLD Breast imaging Breast imaging Mammography CHF CT Paranasal CT Scanner Price CT angiography CT coronary angiography CT technology CV junction CXR teaching files Carcinoid Contrast Agent Creutzfeldt-Jakob Disease Dams MD/ms Dams grand rounds Diffusion weighted imaging Dysmenorrhea E E World Award 2011 EYE Embolization Imaging Entrepreneurship FMG India FMGE FNH Focal liver lesions ultrasound Focal nodular hyperplasia GBM GI Gall bladder Glioblastoma multiforme Glomus jugulare HEAD HEART HRCT HSG Head injury ICA dissection IRIA 2011 IUGR IVC filter Iliotibial Band Friction Syndrome Job Info Kidney Cancer LV thrombus Leptomeningeal cyst MAMOGRAPHY MCI Screening MD MPPG MR mammography MR urography MRA MRCP MRI Cervical MRI update MRI/PET MRV Mesenteric ischemia Middle East respiratory syndrome coronavirus (MERS-CoV) Motor neuron disease NECK Normal Liver US Oncology trial PDF Radiology PM and R Physician PNS Partial anomalous pulmonary venous drainage Persistent trigeminal artery Pg entrance Physiatrist Physiatry Physician Assistant Plastic Surgery Price MRI Machines 2017 Pulmonology Pulvinar sign Radiology Price List Radiology Today Radiology Updates Radiology grandrounds Radiology images of GI Tract Renal Ultrasound Retinal Surgery Rheumatology Ryles tube SKULL Seizure Sellar Masses Sleep Medicine Sports Medicine Subdural hematoma Surgery TBM TRIANGULAR FIBROCARTILAGE COMPLEX Trauma Surgery URI Ultrasound HIV Umbilical vein Update Article Upper Extremity X Ray Urology Usmle VHL Vascular Surgery Veteran Affairs X Ray Head about accessory bone acute cerebillitis acute pancreatitis aiims may 2011 aipg ankle ankle fracture apple articular cartilage aspergilloma atherosclerosis avulsion injury awards bankart lesion basilar artery thrombosis bilateral phaeochromocytoma biopsy bipolar bohler's angle bone tumours brachial plexus brain tb brainstem stroke branchial cyst breast cancer screening buford complex business today calcaneal fracture calcium scoring canned reports carcinoma esophagus carcinoma stomach cardiac ct/pet cardiac pacemaker cardiogen 82 cardiothoracic imaging catrotid artery dissection cavernoma cervical lymphnode levels chest radiographic score chest radiographs choledocolithiasis classification cloud computing cochlear implant colloid cyst communication in radiology compare case concha bullosa congenital brain anomalies congenital heart disease coronary CT coronary artery disease corpus callosum agenesis craniopharyngioma cryptococcal meningitis ct abdomen and pelvis cystic renal disease dams usmle dams visual treat deep brain stimulator dengue dengue hemorrhagic fever developmental dysplasia devices diagnostic imaging dialysis diffusion MR imaging diffusion tensor imaging diffusion tractography digital radiography distal facial neuroma dsa duplication gall bladder echinococcus echocardiography ectopic kidney elearning elevated diaphragm epilepsy esop facial neuroma fibular osteosarcoma functional mri gastrointenstinal tuberculosis germinoma gifts glioma google google plus gun shot injury haemangioblastoma health 2.0 healthcare consultancy hemangiblastoma hemophilia hippocampus hirayama disease hydatid cyst hypercoagulable hypoxic ischemic encephalopathy indian conferences inferior rectus anomaly infrared interior tomography interstitial lung disease intramedullary metastates intramedullary tuberculomas ipad ipad 2 jacoud's arthropathy kernohan's notch knee kohler's disease krukenberg tumour laceration leber's optic atrophy liver transplant lung contusion lymphatics macros marchifava bingami disease mastoiditis maxillary sinus mucocele medial malleolus ossicle medial tibial stress syndrome medical writting medicare medicolegal aspects of teleradiology migraine mortality motor area mri knee mri lumbal msk penang course mucinous cystadenoma multicentric Glioblastoma multiforme mycotic pseudoaneurysm of superficial temporal artery nephrogenic systemic fibrosis nephrology neurosurgery meets nonradiologist oesophagus olecranon spur online medical games open access opercular syndrome opinion orbit os odontoideum os radiale externum osirix osteochondritis osteochondroma osteoid osteoma outsourcing radiology ovarian tumour parameniscal cyst paranasal sinuses parotid vascular mass patellar sleeve avulsion fracture patent ductus arteriosus patent foramen ovale patient information pelvic MRI pericardial fat phaeochromocytoma pharmaceutical writting pineal tumour placenta accreta placenta increta placental insufficiency pneumococcal pneumonia polycystic kidney disease portal Hypertension posterior circulation stroke power point presentation primary complex protected health information pseudobulbar palsy pseudomyxoma peritonei publications pulmonary edema pulmonary embolism pulmonary tuberculosis rabbit ear sign rad radiographic deterioration pattern radiography radiolo radiologist blogs radiology city radiology debate radiology images of spleen radiology intervensional radiology learning radiology search engine radiology spotter radiology spotters radiolopolis raditudes rathke cleft cyst renal imaging renal sinus tumour right sided aortic arch robot round cell tumour sacral agenesis scaphoid fracture schatzki ring scientific content screening search engine secondaries secondary ossification centres silicosis social radiology soft tissue chondroma solitary pulmonary nodule spectroscopy spinal arachnoid cyst spinal cord tumours spinal osteochondroma spine tumour spinoglenoid cyst sternal tuberculosis stress fracture sacrum stroke mri sub-acute combined degeneration subclavian pseudoaneurysm subependymal giant cell astrocytoma sumer sethi swyer-james syndrome syringomyelia tb teaching video teleradiolo teleradiology business models teleradproviders teleultrasound temporal bone fracture tendoachilles testicular tumour tethered cord. MRI tibial stress fracture total knee arthroplasty total shoulder replacment trachea. tracheal diverticulum tracheal stenosis tracheomalacia traumatic lung cyst triceps tear triquetral fracture tubercular abscess tuberculoma tuberculosis elbow ultrasound image of The segments of the liver umblical artery doppler uroradiology vascular malformation vasovist venous angioma ventriculitis video ct scan video mri viral encephalitis vitamin deficiency