Subcategories
- Abdominal aortic aneurysm
- Abscess, Bartholin's
- Absence seizure (petit mal seizure)
- Acanthosis nigricans
- Achilles tendinitis
- Achilles tendon rupture
- Acid reflux
- Acid reflux, infant
- ACL injury
- Acne
- Acoustic neuroma
- Acromegaly
- Actinic keratosis
- Acute coronary syndrome
- Acute febrile neutrophilic dermatosis
- Acute kidney failure
- Acute liver failure
- Acute lymphocytic leukemia
- Acute myelogenous leukemia (AML)
- Acute myelogenous leukemia
- Acute radiation sickness
- Acute radiation syndrome
- ARDS
- Acute respiratory distress syndrome
- Acute sinusitis
- Alcoholism
- Addiction, alcohol
- Addiction, drug
- Addiction, gambling
- Addiction, nicotine
- Addiction, tobacco
- Addison's disease
- Adrenal insufficiency
- Adult ADHD (attention-deficit/hyperactivity disorder)
- Adenitis, mesenteric
- Adenomyosis
- Attention-deficit/hyperactivity disorder (ADHD) in children
- ADHD, Adult
- ADHD, in children
- Adhesive capsulitis
- Adjustment disorders
- Adolescent schizophrenia
- Adult Still's disease
- Age spots (liver spots)
- Age spots
- Age-related hearing loss
- Age-related macular degeneration, dry
- Age-related macular degeneration, wet
- Agnogenic myeloid metaplasia
- Agoraphobia
- AIDS/HIV
- Airplane ear
- Albinism
- Alcohol addiction
- Alcohol intolerance
- Alcohol poisoning
- Alcohol-related birth defects
- Alcohol-related neurodevelopmental disorder
- Alcoholic hepatitis
- Autonomic neuropathy
- Aldosteronoma
- Allergic angiitis
- Allergic granulomatosis
- Allergies
- Allergic reaction
- Allergic rhinitis
- Allergy
- Allergy, dust mite
- Allergy, egg
- Allergy, food
- Allergy, latex
- Allergy, milk
- Allergy, mold
- Allergy, nickel
- Allergy, peanut
- Allergy, penicillin
- Allergy, pet
- Allergy, shellfish
- Allergy, soy
- Allergy, sulfa
- Allergy, wheat
- Alopecia
- Amyotrophic lateral sclerosis
- ALS
- Alveolar osteitis
- Alzheimer's disease
- Ambiguous genitalia
- Amblyopia
- Amenorrhea
- American trypanosomiasis
- Amnesia
- Amnesia, dissociative
- Amnesia, transient global
- Amnestic syndrome
- Amyloidosis
- ANA test
- Anal cancer
- Anal fissure
- Anal itching
- Anaphylaxis
- Anaplasmosis
- Anemia
- Aplastic anemia
- Anemia, aplastic
- Anemia, Cooley's
- Anemia, iron deficiency
- Anemia, Mediterranean
- Anemia, sickle cell
- Anemia, vitamin deficiency
- Aneurysm, aortic
- Aneurysm, cerebral
- Angelman syndrome
- Angiitis
- Angiitis, allergic
- Angina
- Angina pectoris
- Angioedema and hives
- Angiofollicular lymph node hyperplasia
- Angioplasty, carotid
- Anhidrosis
- Ankle fracture
- Ankle sprain
- Ankyloglossia
- Ankylosing spondylitis
- Anorexia nervosa
- Anorgasmia in women
- Anterior cruciate ligament injury
- Anthrax
- Antibiotic-associated diarrhea
- Antiphospholipid syndrome
- Antisocial personality disorder
- Anxiety
- Anxiety disorder, generalized
- Anxiety disorder, social
- Aortic aneurysm
- Aortic calcification
- Aortic coarctation
- Aortic dissection
- Aortic valve regurgitation
- Aortic valve stenosis
- Aphasia
- Aphasia, primary progressive
- Aphthous ulcer
- Apical ballooning syndrome
- Apnea, sleep
- Apnea, sleep (central)
- Apnea, sleep (obstructive)
- Appendicitis
- Argentine hemorrhagic fever
- Arm fracture
- Arrhythmia
- Arteriosclerosis / atherosclerosis
- Arteriovenous fistula
- Arteriovenous malformation
- Arteritis, giant cell
- Arthritis
- Arthritis, basal
- Arthritis, gouty
- Arthritis, septic
- Arthritis, thumb
- Arthritis, infectious
- Arthritis, juvenile rheumatoid
- Arthritis, osteoarthritis
- Arthritis, psoriatic
- Arthritis, reactive
- Arthritis, rheumatoid
- Asbestosis
- Ascariasis
- Atrial septal defect (ASD)
- Asperger's syndrome
- Aspergillosis
- Asthma
- Asthma attack
- Asthma, childhood
- Asthma, exercise-induced
- Asthma, occupational
- Astigmatism
- Ataxia
- Atelectasis
- Athlete's foot
- Atopic dermatitis (eczema)
- Atrial fibrillation
- Atrioventricular canal defect
- Atrioventricular septal defect
- Atrophic vaginitis
- Attachment disorder
- Atypical depression
- Atypical hyperplasia of the breast
- Autism
- Autoimmune hepatitis
- Avascular necrosis
- Avian influenza
- Avoidant personality disorder
- Avulsion fracture


