Internal Medicine Acronyms

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Internal Medicine Alphabet – A

S. No	Acronyms	Full Form	Short Explanation	Practical Example
A001	AAA	Abdominal Aortic Aneurysm	Localized dilation of abdominal aorta, risk of rupture.	CT scan confirms AAA in patient with sudden abdominal pain.
A002	AAT	Alpha-1 Antitrypsin	Protein preventing lung/liver damage; deficiency causes emphysema.	Screen AAT deficiency in young COPD patient.
A003	ABG	Arterial Blood Gas	Measures oxygen, CO₂, and pH in arterial blood.	ICU patient requires ABG to guide ventilation.
A004	ABI	Ankle-Brachial Index	Compares ankle and arm BP to assess PAD.	ABI <0.9 indicates peripheral arterial disease.
A005	ACE	Angiotensin-Converting Enzyme	Converts angiotensin I → II; regulates BP.	Prescribe ACE inhibitor in hypertension.
A006	ACL	Anterior Cruciate Ligament	Major stabilizing knee ligament.	MRI ordered for ACL tear in athlete.
A007	ACS	Acute Coronary Syndrome	Reduced blood flow in coronary arteries.	STEMI is a form of ACS.
A008	ACTH	Adrenocorticotropic Hormone	Stimulates cortisol release from adrenal glands.	ACTH test diagnoses adrenal insufficiency.
A009	ADH	Antidiuretic Hormone	Regulates water balance via kidney reabsorption.	SIADH causes hyponatremia.
A010	AF	Atrial Fibrillation	Irregular atrial rhythm, increases stroke risk.	Patient started on anticoagulants for AF.
A011	AFP	Alpha-Fetoprotein	Tumor marker for liver/testicular cancers.	Elevated AFP in hepatocellular carcinoma.
A012	AIDS	Acquired Immunodeficiency Syndrome	Advanced HIV with immune suppression.	PCP pneumonia common in AIDS.
A013	AKI	Acute Kidney Injury	Sudden loss of kidney function.	AKI due to dehydration improved with IV fluids.
A014	ALP	Alkaline Phosphatase	Enzyme elevated in bone and liver disease.	Raised ALP in cholestasis.
A015	ALT	Alanine Aminotransferase	Marker of hepatocellular injury.	ALT elevated in hepatitis.
A016	AMA	Against Medical Advice	Patient refuses care and leaves hospital.	Chest pain patient leaves AMA.
A017	ANA	Antinuclear Antibody	Autoantibody in autoimmune disease.	Positive ANA in lupus diagnosis.
A018	ANCA	Antineutrophil Cytoplasmic Antibody	Autoantibody in vasculitis.	Positive ANCA in GPA vasculitis.
A019	ANC	Absolute Neutrophil Count	Measures neutrophils; low = infection risk.	ANC <500 in chemo patient = neutropenia.
A020	ARDS	Acute Respiratory Distress Syndrome	Severe hypoxemia requiring ventilation.	ARDS develops in septic patient.
A021	ARF	Acute Renal Failure	Sudden kidney function loss.	ARF after drug toxicity.
A022	AS	Aortic Stenosis	Narrowing of aortic valve → obstruction.	Systolic murmur suggests AS.
A023	AST	Aspartate Aminotransferase	Enzyme elevated in liver/muscle injury.	AST high in alcoholic hepatitis.
A024	ATN	Acute Tubular Necrosis	Renal tubular cell death from ischemia/toxins.	ATN common in septic shock.
A025	AV	Arteriovenous	Relating to arteries and veins.	AV fistula used in dialysis.
A026	AVM	Arteriovenous Malformation	Abnormal artery-vein connection.	Brain AVM causes seizures.
A027	AVN	Avascular Necrosis	Bone death due to poor blood supply.	AVN of femoral head in steroid user.
A028	AVR	Aortic Valve Replacement	Surgery for severe aortic valve disease.	AVR done in critical AS.
A029	AVRT	Atrioventricular Reentrant Tachycardia	Reentry arrhythmia using accessory pathway.	Seen in WPW syndrome.
A030	AVNRT	Atrioventricular Nodal Reentrant Tachycardia	Supraventricular tachycardia mechanism.	AVNRT terminated by adenosine.
A031	APL	Acute Promyelocytic Leukemia	Subtype of AML, t(15;17).	Treat with ATRA.
A032	AML	Acute Myeloid Leukemia	Cancer of myeloid lineage.	AML presents with pancytopenia.
A033	ALL	Acute Lymphoblastic Leukemia	Lymphoid precursor malignancy.	Common childhood leukemia.
A034	AMI	Acute Myocardial Infarction	Heart attack due to ischemia.	STEMI confirmed with troponin rise.
A035	ASA	Acetylsalicylic Acid (Aspirin)	Antiplatelet drug.	ASA used in ACS management.
A036	ASTH	Asthma	Chronic airway inflammation.	Patient uses inhaler for asthma.
A037	ASO	Antistreptolysin O	Antibody against strep infection.	Elevated ASO in rheumatic fever.
A038	AVB	Atrioventricular Block	Impaired conduction at AV node.	ECG shows AV block.
A039	AUB	Abnormal Uterine Bleeding	Irregular menstrual bleeding.	Workup for AUB with ultrasound.
A040	ACD	Anemia of Chronic Disease	Hypoproliferative anemia due to inflammation.	Seen in CKD patients.
A041	AIHA	Autoimmune Hemolytic Anemia	Antibody-mediated RBC destruction.	Positive Coombs test in AIHA.
A042	ARF2	Acute Rheumatic Fever	Post-strep immune reaction.	ARF presents with arthritis, carditis.
A043	AVH	Acute Viral Hepatitis	Sudden liver inflammation due to virus.	ALT/AST elevated in hepatitis B.
A044	ABE	Acute Bacterial Endocarditis	Infection of heart valves.	Staphylococcus aureus causes ABE.
A045	APD	Acute Pancreatitis	Inflammation of pancreas.	Alcohol-induced APD.
A046	APACHE	Acute Physiology and Chronic Health Evaluation	ICU severity scoring system.	APACHE score predicts ICU mortality.
A047	AIMS	Abnormal Involuntary Movement Scale	Tool to measure tardive dyskinesia.	Used in antipsychotic monitoring.
A048	AR	Aortic Regurgitation	Backflow of blood through aortic valve.	Diastolic murmur in AR.
A049	AI	Aortic Insufficiency	Same as AR.	AI noted on echocardiogram.
A050	ANP	Atrial Natriuretic Peptide	Hormone regulating fluid balance.	Elevated ANP in heart failure.
A051	ABPM	Ambulatory Blood Pressure Monitoring	24-hour blood pressure tracking.	ABPM used in white coat hypertension.
A052	AED	Automated External Defibrillator	Portable device to deliver shocks in cardiac arrest.	AED used in airport for VF arrest.
A053	AHI	Apnea-Hypopnea Index	Sleep apnea severity measure.	AHI >30 indicates severe OSA.
A054	ALI	Acute Lung Injury	Non-cardiogenic pulmonary edema.	Trauma patient develops ALI.
A055	AGA	Appropriate for Gestational Age	Neonatal growth classification.	Baby born AGA at 38 weeks.
A056	ATD	Antithyroid Drugs	Medications for hyperthyroidism.	Methimazole is an ATD.
A057	AIT	Amiodarone-Induced Thyrotoxicosis	Thyroid dysfunction from amiodarone.	Monitor TSH in long-term amiodarone use.
A058	ARPKD	Autosomal Recessive Polycystic Kidney Disease	Genetic cystic kidney disease in children.	Infant with enlarged kidneys and ARPKD.
A059	ADPKD	Autosomal Dominant Polycystic Kidney Disease	Adult-onset cystic kidney disorder.	Hematuria in patient with ADPKD.
A060	ACR	Albumin-to-Creatinine Ratio	Measure of albuminuria in diabetes.	ACR >30 mg/g indicates microalbuminuria.
A061	ADA	Adenosine Deaminase	Enzyme marker for TB pleural effusion.	High ADA in pleural fluid suggests TB.
A062	ALD	Alcoholic Liver Disease	Spectrum of liver injury from alcohol.	Ascites in patient with ALD.
A063	AP	Angina Pectoris	Chest pain due to myocardial ischemia.	Stable AP relieved by rest.
A064	ADL	Activities of Daily Living	Functional assessment in geriatrics.	ADL score used in nursing homes.
A065	AFI	Amniotic Fluid Index	Measure of amniotic fluid by ultrasound.	Low AFI in oligohydramnios.
A066	AMR	Antimicrobial Resistance	Pathogen resistance to antibiotics.	MRSA is an AMR example.
A067	ASTS	American Society of Transplant Surgeons	Organization for transplant surgeons.	ASTS guidelines followed in liver transplant.
A068	ASCT	Autologous Stem Cell Transplant	Procedure using patient’s stem cells.	ASCT in multiple myeloma.
A069	allo-SCT	Allogeneic Stem Cell Transplant	Stem cell transplant from donor.	Used in leukemia treatment.
A070	AFB	Acid-Fast Bacilli	Staining test for TB.	AFB positive sputum confirms TB.
A071	AG	Anion Gap	Difference in measured cations and anions.	High AG in metabolic acidosis.
A072	APLA	Antiphospholipid Antibody	Autoantibody causing clotting tendency.	APLA syndrome leads to miscarriages.
A073	APS	Antiphospholipid Syndrome	Hypercoagulable state due to APLA.	Recurrent DVTs in APS.
A074	ASD	Atrial Septal Defect	Hole in atrial septum causing shunt.	ASD detected by echocardiogram.
A075	ASD2	Autism Spectrum Disorder	Neurodevelopmental disorder.	Child with ASD shows impaired social skills.
A076	ASR	Acute Stress Reaction	Short-term response to stress.	Trauma victim shows ASR.
A077	AVF	Arteriovenous Fistula	Surgical connection for dialysis.	AVF created in CKD patient.
A078	AHI2	Apnea-Hypopnea Index	Sleep apnea measurement.	AHI used in CPAP initiation.
A079	ATLS	Advanced Trauma Life Support	Training protocol for trauma care.	ER doctor certified in ATLS.
A080	ACLF	Acute-on-Chronic Liver Failure	Acute insult in chronic liver disease.	ACLF triggered by infection.
A081	ANUG	Acute Necrotizing Ulcerative Gingivitis	Severe gum infection.	HIV patient develops ANUG.
A082	APLAS	Antiphospholipid Antibody Syndrome	Same as APS.	Miscarriages due to APLAS.
A083	APPT	Activated Partial Thromboplastin Time	Coagulation test.	Prolonged APTT in hemophilia.
A084	ATRA	All-Trans Retinoic Acid	Drug for APL treatment.	ATRA started in APL patient.
A085	ATG	Antithymocyte Globulin	Immunosuppressive therapy.	ATG given in aplastic anemia.
A086	ARNI	Angiotensin Receptor Neprilysin Inhibitor	Heart failure drug class.	Sacubitril/valsartan is an ARNI.
A087	ARV	Antiretroviral	HIV treatment drugs.	ARV regimen given to HIV patient.
A088	ART	Antiretroviral Therapy	Combination HIV treatment.	ART started after HIV diagnosis.
A089	ABVD	Adriamycin, Bleomycin, Vinblastine, Dacarbazine	Chemo regimen for Hodgkin’s lymphoma.	ABVD is first-line for Hodgkin’s.
A090	AML-M3	Acute Myeloid Leukemia M3 (APL)	Subtype of AML responsive to ATRA.	AML-M3 treated with ATRA.
A091	ANLL	Acute Non-Lymphocytic Leukemia	Older term for AML.	Bone marrow biopsy confirms ANLL.
A092	ALL2	Acute Lymphocytic Leukemia	Another term for ALL.	Child with ALL on chemo.
A093	AICD	Automatic Implantable Cardioverter-Defibrillator	Device to treat arrhythmias.	AICD implanted after VF arrest.
A094	ASA2	American Society of Anesthesiology Score	Pre-op risk classification.	ASA II = mild systemic disease.
A095	ASR2	Acute Sinusitis Rhinosinusitis	Sinus infection.	Patient treated for ASR.
A096	AOM	Acute Otitis Media	Middle ear infection.	Child with ear pain and fever.
A097	AGE	Acute Gastroenteritis	Sudden vomiting and diarrhea.	AGE caused by norovirus.
A098	ABSSSI	Acute Bacterial Skin and Skin Structure Infection	Severe skin infection.	MRSA causes ABSSSI.
A099	AGC	Atypical Glandular Cells	Pap smear finding.	AGC requires colposcopy.
A100	ASCUS	Atypical Squamous Cells of Undetermined Significance	Cervical cytology abnormality.	ASCUS requires HPV testing.
A101	ACHE	Acetylcholinesterase	Enzyme breaking down acetylcholine.	ACHE inhibitors used in Alzheimer’s.
A102	ADP	Adenosine Diphosphate	Molecule in platelet activation.	ADP blockers (clopidogrel) used in ACS.
A103	ATP	Adenosine Triphosphate	Cellular energy molecule.	ATP used in metabolic pathways.
A104	ATPase	Adenosine Triphosphatase	Enzyme regulating ion gradients.	Na/K ATPase maintains resting potential.
A105	ACTH stim test	ACTH Stimulation Test	Test of adrenal reserve.	Used to diagnose Addison’s disease.
A106	ADEM	Acute Disseminated Encephalomyelitis	Demyelinating disease post-infection.	ADEM seen in children post-viral illness.
A107	ALS	Amyotrophic Lateral Sclerosis	Neurodegenerative disease of motor neurons.	ALS presents with progressive weakness.
A108	AMR2	Acute Mixed Rejection	Transplant rejection type.	AMR managed with immunosuppression.
A109	ATD2	Antitubercular Drugs	Drugs for TB treatment.	INH, Rifampin are ATD.
A110	ATS	American Thoracic Society	Lung health organization.	ATS guidelines for COPD.
A111	ASV	Antisnake Venom	Antitoxin for snake bites.	ASV administered in cobra bite.
A112	APLA2	Antiphospholipid Antibody	Autoantibody.	APLA linked with miscarriages.
A113	AACE	American Association of Clinical Endocrinologists	Professional body for endocrinologists.	AACE guidelines followed in diabetes.
A114	ADA2	American Diabetes Association	Body issuing diabetes care standards.	ADA criteria for diabetes diagnosis.
A115	ADA-SCID	Adenosine Deaminase Severe Combined Immunodeficiency	Genetic immune deficiency.	ADA-SCID treated with gene therapy.
A116	AATD	Alpha-1 Antitrypsin Deficiency	Genetic deficiency.	AATD patient develops emphysema.
A117	AGN	Acute Glomerulonephritis	Kidney inflammation.	AGN after strep throat.
A118	AHFS	American Hospital Formulary Service	Drug reference source.	AHFS used in hospital pharmacy.
A119	AION	Anterior Ischemic Optic Neuropathy	Sudden optic nerve infarct.	AION causes acute vision loss.
A120	AMI2	Acute Mesenteric Ischemia	Ischemia of intestines.	AMI presents with severe abdominal pain.
A121	AMP	Adenosine Monophosphate	Nucleotide in metabolism.	AMP kinase regulates metabolism.
A122	AMR3	Antibody-Mediated Rejection	Transplant rejection.	AMR confirmed with biopsy.
A123	AMS	Altered Mental Status	Change in consciousness.	AMS in hypoglycemia.
A124	ANA2	Antinuclear Antibody	Autoantibody.	ANA positive in lupus.
A125	ANF	Atrial Natriuretic Factor	Same as ANP.	ANF elevated in CHF.
A126	AOT	Acute Obstructive Tracheitis	Severe airway infection.	AOT in children post-viral illness.
A127	APS2	Autoimmune Polyendocrine Syndrome	Multiple endocrine autoimmune disorders.	APS includes Addison’s and thyroiditis.
A128	APH	Antepartum Hemorrhage	Bleeding before delivery.	APH seen in placenta previa.
A129	ARB	Angiotensin Receptor Blocker	Antihypertensive drug.	ARB used in hypertension.
A130	ARDSnet	ARDS Network	Clinical trial group for ARDS.	ARDSnet protocol guides ventilation.
A131	ARC	AIDS-Related Complex	Symptomatic stage of HIV.	ARC precedes AIDS.
A132	ARF3	Acute Respiratory Failure	Failure of lungs to oxygenate.	ARF needs ventilation.
A133	ARR	Aldosterone-to-Renin Ratio	Screen for hyperaldosteronism.	High ARR in Conn’s syndrome.
A134	ASAT	Aspartate Aminotransferase	Liver enzyme.	AST also known as ASAT.
A135	ASHD	Arteriosclerotic Heart Disease	Old term for coronary artery disease.	ASHD diagnosed via angiogram.
A136	ASI	Ankle Systolic Index	Similar to ABI.	ASI <0.9 in PAD.
A137	ASLV	Anteroseptal Left Ventricular	ECG localization term.	ASLV MI seen in V1–V4.
A138	ASP	Aspiration Pneumonia	Pneumonia from inhaled contents.	ASP seen in stroke patient.
A139	AST2	Aspartate Aminotransferase	Enzyme.	AST high in cirrhosis.
A140	ATA	American Thyroid Association	Professional body.	ATA guidelines for thyroid cancer.
A141	ATLS2	Advanced Trauma Life Support	Trauma training.	ATLS protocols followed.
A142	ATN2	Acute Tubular Necrosis	Kidney injury.	ATN after ischemia.
A143	ATR	Atrial Tachycardia	Supraventricular arrhythmia.	ATR diagnosed on ECG.
A144	ATV	Atazanavir	Antiretroviral drug.	ATV used in HIV therapy.
A145	AUGIB	Acute Upper GI Bleed	Hematemesis and melena.	AUGIB from peptic ulcer.
A146	AVF2	Arteriovenous Fistula	Dialysis access.	AVF created surgically.
A147	AVN2	Avascular Necrosis	Bone necrosis.	AVN of hip seen on MRI.
A148	AVSD	Atrioventricular Septal Defect	Congenital heart defect.	AVSD in Down syndrome.
A149	AVWS	Acquired von Willebrand Syndrome	Bleeding disorder.	AVWS in aortic stenosis.
A150	AZT	Zidovudine (Azidothymidine)	Antiretroviral drug.	AZT used in HIV therapy.
A151	Aβ	Amyloid Beta	Protein in Alzheimer’s disease.	Aβ plaques in brain autopsy.
A152	ABPA	Allergic Bronchopulmonary Aspergillosis	Hypersensitivity reaction in asthma.	ABPA diagnosed in asthmatic with high IgE.
A153	ACDF	Anterior Cervical Discectomy and Fusion	Spine surgery.	ACDF done for cervical myelopathy.
A154	ACEi	Angiotensin-Converting Enzyme Inhibitor	BP-lowering drug.	ACEi prescribed for heart failure.
A155	ACh	Acetylcholine	Neurotransmitter.	ACh reduced in Alzheimer’s.
A156	AChR	Acetylcholine Receptor	Autoantibody target in myasthenia gravis.	Positive AChR antibody test.
A157	ACNES	Abdominal Cutaneous Nerve Entrapment Syndrome	Cause of abdominal wall pain.	ACNES mimics appendicitis.
A158	ACS2	Acute Coronary Syndrome	Cardiac ischemia spectrum.	ACS confirmed by troponin.
A159	ACTA	Arterial Compliance Test for Aorta	Vascular test.	ACTA used in research.
A160	ADA3	Adenosine Deaminase	Enzyme.	ADA high in TB.
A161	ADHF	Acute Decompensated Heart Failure	Sudden worsening of CHF.	Dyspnea in ADHF.
A162	ADR	Adverse Drug Reaction	Harmful drug effect.	Rash due to penicillin ADR.
A163	AED2	Antiepileptic Drug	Drug for seizure control.	AED prescribed in epilepsy.
A164	AFO	Ankle-Foot Orthosis	Brace for foot drop.	AFO used in stroke rehab.
A165	AGI	Acute Gastrointestinal Infection	GI infection with diarrhea.	AGI due to salmonella.
A166	AGN2	Acute Glomerulonephritis	Kidney disease.	AGN post-strep.
A167	AHE	Acute Hepatic Encephalopathy	Brain dysfunction from liver failure.	AHE treated with lactulose.
A168	AHF	Acute Heart Failure	Sudden cardiac decompensation.	AHF needs IV diuretics.
A169	AHU	Acute Hematuria	Sudden appearance of blood in urine.	AHU caused by kidney stones.
A170	AI2	Adrenal Insufficiency	Cortisol deficiency.	AI confirmed with cortisol test.
A171	AIDP	Acute Inflammatory Demyelinating Polyneuropathy	Guillain-Barré syndrome subtype.	AIDP causes paralysis.
A172	AIM	Acute Intermittent Porphyria	Rare metabolic disorder.	AIM causes abdominal pain and neuropathy.
A173	AION2	Arteritic Ischemic Optic Neuropathy	Optic nerve infarct due to GCA.	AION seen in temporal arteritis.
A174	ALCL	Anaplastic Large Cell Lymphoma	T-cell lymphoma.	ALCL diagnosed on biopsy.
A175	ALF	Acute Liver Failure	Sudden liver dysfunction.	ALF due to acetaminophen overdose.
A176	ALLHAT	Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial	Major clinical trial.	ALLHAT studied BP meds.
A177	ALRI	Acute Lower Respiratory Infection	Chest infection.	ALRI includes pneumonia.
A178	AMAN	Acute Motor Axonal Neuropathy	GBS subtype.	AMAN seen after Campylobacter infection.
A179	AMC	Absolute Monocyte Count	Blood test parameter.	AMC elevated in infection.
A180	AML2	Acute Megakaryoblastic Leukemia	Rare AML subtype.	AML2 in Down syndrome.
A181	AMN	Adrenomyeloneuropathy	X-linked disorder.	AMN affects adrenal and spinal cord.
A182	AMPK	AMP-Activated Protein Kinase	Energy sensor enzyme.	AMPK activated in exercise.
A183	AMS2	Acute Mountain Sickness	Hypoxia-related illness.	AMS at high altitude.
A184	ANA3	Anti-Nuclear Antibody	Autoantibody.	ANA positive in lupus.
A185	ANP2	Atrial Natriuretic Peptide	Hormone.	ANP elevated in CHF.
A186	ANS	Autonomic Nervous System	Controls involuntary functions.	ANS dysfunction causes orthostatic hypotension.
A187	AO	Aortic Occlusion	Blockage of aorta.	AO seen in trauma.
A188	AODM	Adult-Onset Diabetes Mellitus	Old term for T2DM.	AODM patient starts metformin.
A189	AOSD	Adult-Onset Still’s Disease	Rare inflammatory disorder.	AOSD presents with fever and rash.
A190	APA	Adenoma Producing Aldosterone	Cause of primary aldosteronism.	APA detected on adrenal CT.
A191	APC	Activated Protein C	Anticoagulant protein.	APC deficiency causes thrombosis.
A192	APGAR	Appearance, Pulse, Grimace, Activity, Respiration	Newborn scoring system.	APGAR score taken at 1 and 5 minutes.
A193	APE	Acute Pulmonary Embolism	Clot in pulmonary artery.	APE confirmed with CT angiogram.
A194	APL2	Antiphospholipid Antibody	Autoantibody.	APL positive in clotting disorder.
A195	APRI	AST to Platelet Ratio Index	Fibrosis marker in hepatitis.	APRI >1 indicates cirrhosis.
A196	ARDS2	Acute Respiratory Distress Syndrome	Severe hypoxemia.	ARDS post-sepsis.
A197	ARF4	Acute Renal Failure	Kidney injury.	ARF after contrast exposure.
A198	ARR2	Aldosterone-to-Renin Ratio	Screening test.	ARR high in Conn’s.
A199	ASAT2	Aspartate Aminotransferase	Liver enzyme.	ASAT elevated in hepatitis.
A200	AST3	Aspartate Aminotransferase	Marker of hepatocellular injury.	AST high in alcoholic liver disease.