• Aarskog Syndrome
• Abdominal Hernia
• Abdominal Muscle Strain
• Abscessed Tooth
• Acanthosis Nigricans

• Acetaminophen Poisoning
• Achalasia
• Achilles Tendinopathy
• Achilles Tendon Rupture
• Achondroplasia

• Acne
• Acromegaly
• ACTH
• Actinic Keratosis
• Actinomycosis

• Acute Abdomen
• Acute Cerebellar Ataxia
• Acute Colonic Pseudo-Obstruction
• Acute Compartment Syndrome
• Acute Coronary Syndrome

• Acute Interstitial Nephritis
• Acute Lymphoblastic Leukemia
• Acute Myelogenous Leukemia
• Acute Necrotizing Ulcerative Gingivitis
• Acute Renal Failure

• Acute Respiratory Distress Syndrome
• Acute Silicosis
• Acute Tubular Necrosis
• Addictions +
  • Alcoholism
  • Compulsive Gambling
  • Delirium Tremens
  • Drug Addictions
  • Narcotic Abuse
  • Opioid Abuse
  • Prescription Drug Addiction
• Addison's Disease

• Adenovirus infection
• Adjustment Disorder
• Adrenal Cancer
• Adrenal Crisis
• Adrenal Gland Tumor

• Adrenalin
• Adult Macular Degeneration
• Age-Related Hearing Loss
• Aging Skin
• Agoraphobia

• AIDS / HIV
• Albinism
• Alcoholism
• Aldosterone
• Alexic Anomia

• Allergic Bronchopulmonary Aspergillosis (ABPA)
• Allergic Contact Dermatitis
• Allergic Rhinitis
• Allergies +
  • Anaphylatic Shock
  • Food Allergies
  • Hay Fever
  • Insect Allergies
• Aluminum Toxicity

• Alzheimer's Disease
• Amenorrhea
• Amoebic Dysentery
• Amyloidosis
• Amyotrophic Lateral Sclerosis

• Anal Abscess
• Anal Atresia
• Anal Cancer
• Anal Fissure
• Anaphylatic Shock

• Anemia +
  • Aplastic Anemia
  • Autoimmune Hemolytic Anemia
  • Sickle Cell Anemia
  • Thalassemia
• Anemia of Chronic Disease
• Angina
• Angiodysplasia of the Colon
• Angioedema

• Angle-Closure Glaucoma
• Animal Bites
• Ankle Sprain
• Ankylosing Spondylitis
• Anorexia Nervosa

• Anovulation
• Anoxic Brain Injury
• Anserine Tendinobursitis Syndrome
• Anterior Cruciate Ligament Injury
• Anthrax

• Antibiotic-associated Colitis—C difficile
• Antisocial Personality Disorder
• Anxiety
• Aortic Aneurysm
• Aortic Coarctation

• Aortic Dissection
• Aortic Insufficiency
• Aortic Regurgitation
• Aortic Stenosis
• Aphasia

• Aphasia-associated Anomia
• Aphonia
• Aplastic Anemia
• Apoplexy
• Appendicitis

• Apraxia
• Arnold-Chiari Syndrome
• Arrhenoblastoma
• Arrhythmia +
  • Atrial Flutter
  • Bradycardia
  • Sick Sinus Syndrome
  • Tachycardia
  • Ventricular Fibrillation
  • Ventricular Premature Beats
  • Ventricular Tachycardia
• Arrhythmias

• Arsenic Toxicity
• Arteriovenous Malformations of the Brain
• Arthritis +
  • Gout
  • Infectious Arthritis
  • Osteoarthritis
• Asbestosis
• Ascariasis

• Ascites
• Aseptic Meningitis
• Aseptic Necrosis of the Hip
• Asperger's Syndrome
• Aspergillosis

• Aspiration Pneumonia
• Asthma
• Asthma—Child
• Astigmatism
• Astrocytoma

• Atelectasis
• Atherosclerosis
• Athlete's Foot
• Atopic Dermatitis
• Atrial Fibrillation

• Atrial Flutter
• Atrial Septal Defect
• Atrioventricular Septal Defect
• Atrophic Vaginitis
• Attention Deficit Hyperactivity Disorder (ADHD)

• Atypical Pneumonia
• Auditory Neuropathy
• Autism
• Autoimmune Hemolytic Anemia
• Avian Influenza