A-a gradientalveolar-arterial gradient
A-aDO2alveolar arterial O2 difference of each
A&Eaccident and emergency
A&Pauscultation and percussion
A1ATDalpha-1-antitrypsin deficiency
A2aortic component of second heart sound
AA&Oawake, alert, and oriented
AAAAbdominal Aortic Aneurysm
AACEAmerican Association of Clinical Endocrinologists
AAGautoimmune autonomic ganglionopathy
AAGSVanterior accessory great saphenous vein
AAK1AP2-associated protein kinase 1
AANAmerican Academy of Neurology
AAOAmerican Academy of Ophthalmology
AAOSAmerican Academy of Orthopaedic Surgeons
AAPAmerican Academy of Pediatrics
AAROMactive assisted range of motion
AASLDAmerican Association for the Study of Liver Disease
AASMAmerican Academy of Sleep Medicine
AASTAmerican Association for the Surgery of Trauma
AASVanterior accessory saphenous vein
AATDalpha-1 antitrypsin deficiency
AATSAmerican Association for Thoracic Surgery
AAVadeno-associated virus
ABAapplied behavior analysis
ABAS-3Adaptive Behavior Assessment System, Third Edition
ABCactive breathing control
ABICage, serum bilirubin, international normalized ratio, and serum creatinine
ABLAacute blood loss anemia
ABLLS-RAssessment of Basic Language and Learning Skills, Revised
ABParterial blood pressure
ABPAallergic bronchopulmonary aspergillosis
ABVDAdriamycin, bleomycin, vinblastine, dacarbazine
ACAdriamycin + Cyclophosphamide
ACCAmerican College of Cardiology
ACDattention concentration deficit
ACDFAnterior Cervical Decompression & Fusion
ACEAngiotensin Converting Enzyme
ACE-IAngiotensin Converting Enzyme Inhibitor
ACE2angiotensin-converting enzyme 2
ACGAmerican College of Gastroenterology
aCGHarray comparative genomic hybridization
ACIAutologous Cartilage Implantation
ACLanterior cruciate ligament
ACLRanterior cruciate ligament reconstruction
ACLSadvanced cardiac life support
ACMarrhythmogenic cardiomyopathy
ACOGAmerican College of Obstetricians and Gynecologists
ACPAmerican College of Physicians
ACRAmerican College of Radiology
ACSAmerican Cancer Society
ACTActivating Clotting Time
ACTHadrenocorticotropic hormone
ACVassist control ventilation
ACVDarteriosclerotic cardiovascular disease
ADAAmerican Diabetes Association
ADDattention deficit disorder
ADHDattention deficit hyperactivity disorder
ADHFacute diastolic heart failure
ADLactivities of daily living
ADOS-2Autism Diagnostic Observation Schedule, Second Edition
ADPKDautosomal dominant polycystic kidney disease
ADRB3β3-adrenergic receptor
AECOPDacute exacerbations of chronic obstructive pulmonary disease
AFAFPAmniotic Fluid Alpha-Fetoprotein
AFLSAssessment of Functional Living Skills
AFMAcute Flaccid Myelitis
AFSAmerican Foregut Society
AFTAutologous Fat Transfer
AFVSSafebrile, vital signs stable
AGAAmerican Gastroenterological Association
AGBAdjustable Gastric Banding
AHAAmerican Heart Association
AHFSAmerican Hospital Formulary Service
AHREatrial high-rate episodes
AHRQAgency for Healthcare Research and Quality
AIBVAvian Infectious Bronchitis Virus
AICDautomatic implantable cardioverter defibrillator
AIDPAcute Inflammatory Demyelinating Polyneuropathy
AIDSacquired immune deficiency syndrome
AIEDAutoimmune Inner Ear Disease
AIHAauto-immune haemolytic anaemia
AIIRDautoimmune inflammatory rheumatic disease
AIRacute inpatient rehabilitation
AIRFacute inpatient rehabilitation facility
AIRR-seqadaptive immune receptor repertoire sequencing
AIUMAmerican Institute of Ultrasound in Medicine
AJCCAmerican Joint Committee on Cancer
ALA-PDT5-aminolevulinic acid-mediated photodynamic therapy
ALDAssistive Listening Device
ALDHaldehyde dehydrogenase
ALIFAnterior Lumbar Interbody Fusion
ALKanaplastic lymphoma kinase
Alk phosalkaline phosphatase
ALLacute lymphocytic leukemia
ALNDaxillary lymph node dissection
ALNTAutologous Lymph Node Transfer
ALSFRSAmyotrophic Lateral Sclerosis Functional Rating Scale
ALSFRS-RRevised Amyotrophic Lateral Sclerosis Functional Rating Scale
ALTalanine aminotransferase
ALTEApparent Life-Threatening Event
AMAantimitochondrial antibody
AMANacute motor axonal neuropathy
AMC-BALAmsterdam Medical Center bioartificial liver
AMDaging macular degeneration
AMHanti-mullerian hormone
AMIacute myocardial infarction
AMLacute myelogenous leukemia
AMLSadvanced medical life support
AMMLacute myelomonocytic leukemia
AMPAmputee Mobility Predictor
ANCabsolute neutrophil count
ANEDalive no evidence of disease
ANFatrial natriuretic factor
ANOVAanalysis of variance
ANPatrial natriuretic peptide
AOBAortic Occlusion Balloon
AOCDAnemia of Chronic Disease
AODatlanto-occipital dislocation
AODMadult-onset diabetes mellitus
AOTAssisted Outpatient Treatment
AP-MSaffinity-purification mass spectrometry
APAAmerican Psychiatric Association
APAAPalkaline phosphatase monoclonal anti-alkaline phosphatase
APAPautotitrating positive airway pressure
APBabductor pollicis brevis
aPC-Ractivated protein C resistance
APCDadvanced pneumatic compression device
APDAutomated Peritoneal Dialysis
APHEarterial phase hyperenhancement
APLabductor pollicis longus
APRAbdominal Perineal Resection
APRVairway pressure release ventilation
APSantiphospholipid syndrome
aPTTactivated partial thromboplastin
AQLQAsthma Quality of Life Questionnaire
ARAGautosomal recessive agammaglobulinemia
ARBangiotensin II receptor blocker
ARCAautosomal-recessive cerebellar ataxia
ARDSacute respiratory distress syndrome
ARManorectal malformation
AROMartificial rupture of membranes
ARTassisted reproductive technology
ARVCarrhythmogenic right ventricular cardiomyopathy
ARVDArrhythmogenic Right Ventricular Dysplasia
AS-OCTanterior segment optical coherence tomography
AS-PCRallele-specific polymerase chain reaction
ASAacetylsalicylic acid (aspirin)
aSAHaneurysmal subarachnoid hemorrhage
ASAMAmerican Society of Addiction Medicine
ASAS 20/40/50/70Assessment in Ankylosing Spondylitis response criteria 20/40/50/70
ASCVDatherosclerotic cardiovascular disease
ASDAdult Spinal Deformity
ASGPRasialoglycoprotein receptor
ASGSAmerican Society of General Surgeons
ASHDarteriosclerotic heart disease
ASHFacute systolic heart failure
ASIAAmerican Spinal Injury Association
ASIA Acomplete spinal injury impairment
ASIA Bincomplete spinal injury impairment; sensory, but not motor, function is preserved below the neurologic level and extends through sacral segments S4-S5
ASIA Cincomplete spinal injury impairment; motor function is preserved below the neurologic level, and most key muscles below the neurologic level have a muscle grade of less than 3
ASIA Dincomplete spinal injury impairment; motor function is preserved below the neurologic level, and most key muscles below the neurologic level have a muscle grade that is greater than or equal to 3
ASIPPAmerican Society of Interventional Pain Physicians
ASMAAnti Smooth Muscle Antibody
ASMBSAmerican Society for Metabolic and Bariatric Surgery
ASNRAmerican Society of Neuroradiology
ASOantisense oligonucleotide
ASRAAmerican Society of Regional Anesthesia and Pain Medicine
ASRMAmerican Society for Reproductive Medicine
ASSFNAmerican Society of Stereotactic and Functional Neurosurgery
ASTaspartate aminotransferase
ASTROAmerican Society for Radiation Oncology
ASUambulatory surgery unit
ASVadaptive servo-ventilation
ASVDatrioventricular septal defect
AT/RTatypical teratoid/rhabdoid tumor
ATAantibodies to adalimumab
ATECAutism Treatment Evaluation Checklist
ATFLanterior talofibular ligament
ATGanti-thymocyte globulin
ATIantibodies to Infliximab
ATLLadult T-cell leukemia/lymphoma
ATMacute transverse myelitis
ATNacute tubular necrosis
ATOMACArizona-Texas-Oklahoma-Memphis-Arkansas Consortium
ATPadenosine triphosphate
ATRachilles tendon rupture
AUAAmerican Urological Association
AUASSAmerican Urological Association Symptom Score
AUBabnormal uterine bleeding
AUDITAlcohol Use Disorders Inventory Test
AURAcute Urinary Retention
AutoPAPautomatic titrating positive airway pressure
AVBTanterior vertebral body tethering
AVDatrioventricular dissociation
AVHAuditory/Visual Hallucination
AVIautomatic volume infusion pump
AVMarteriovenous malformation
AVNRTatrioventricular nodal reentrant tachycardia
aVRAugmented Vector Right
AVRMVRaortic valve repair or replacement mitral valve repair or replacement
AVRTatrioventricular reentrant tachycardia
AVSSafebrile, vital signs stable
AVWSacquired von Willebrand syndrome
AWMIanterior wall myocardial infarction
AWRAbdominal Wall Reconstruction
AZOORacute zonal occult outer retinopathy