- Aarskog\’s syndrome, Q87.19
- Abandonment
- Abasia (-astasia) (hysterical), F44.4
- Abderhalden-Kaufmann-Lignac syndrome (cystinosis), E72.04
- Abdomen, abdominal
- Abdominalgia
- Abduction contracture, hip or other joint
- Aberrant (congenital)
- Aberration
- Abetalipoproteinemia, E78.6
- Abiotrophy, R68.89
- Ablatio, ablation
- Ablepharia, ablepharon, Q10.3
- Abnormal, abnormality, abnormalities
- Abnormity (any organ or part)
- Abocclusion, M26.29
- Abolition, language, R48.8
- Aborter, habitual or recurrent
- Abortion (complete) (spontaneous), O03.9
- Abortus fever, A23.1
- Aboulomania, F60.7
- Abrami\’s disease, D59.8
- Abramov-Fiedler myocarditis (acute isolated myocarditis), I40.1
- Abrasion, T14.8
- Abrism
- Abruptio placentae, O45.9-
- Abruption, placenta
- Abscess (connective tissue) (embolic) (fistulous) (infective) (metastatic) (multiple) (pernicious) (pyogenic) (septic), L02.91
- Absence (of) (organ or part) (complete or partial)
- Absorbent system disease, I87.8
- Absorption
- Abstinence symptoms, syndrome
- Abulia, R68.89
- Abulomania, F60.7
- Abuse
- Acalculia, R48.8
- Acanthamebiasis (with), B60.10
- Acanthocephaliasis, B83.8
- Acanthocheilonemiasis, B74.4
- Acanthocytosis, E78.6
- Acantholysis, L11.9
- Acanthosis (acquired) (nigricans), L83
- Acapnia, E87.3
- Acarbia, E87.29
- Acardia, acardius, Q89.8
- Acardiacus amorphus, Q89.8
- Acardiotrophia, I51.4
- Acariasis, B88.0
- Acarodermatitis (urticarioides), B88.0
- Acarophobia, F40.218
- Acatalasemia, acatalasia, E80.3
- Acathisia (drug induced), G25.71
- Accelerated atrioventricular conduction, I45.6
- Accentuation of personality traits (type A), Z73.1
- Accessory (congenital)
- Accident
- Accidental
- Accommodation (disorder)
- Accouchement
- Accreta placenta, O43.21-
- Accretio cordis (nonrheumatic), I31.0
- Accretions, tooth, teeth, K03.6
- Acculturation difficulty, Z60.3
- Accumulation secretion, prostate, N42.89
- Acephalia, acephalism, acephalus, acephaly, Q00.0
- Acephalobrachia monster, Q89.8
- Acephalochirus monster, Q89.8
- Acephalogaster, Q89.8
- Acephalostomus monster, Q89.8
- Acephalothorax, Q89.8
- Acerophobia, F40.298
- Acetonemia, R79.89
- Acetonuria, R82.4
- Achalasia (cardia) (esophagus), K22.0
- Ache (s)
- Acheilia, Q38.6
- Achillobursitis
- Achillodynia
- Achlorhydria, achlorhydric (neurogenic), K31.83
- Achluophobia, F40.228
- Acholia, K82.8
- Acholuric jaundice (familial) (splenomegalic)
- Achondrogenesis, Q77.0
- Achondroplasia (osteosclerosis congenita), Q77.4
- Achroma, cutis, L80
- Achromat (ism), achromatopsia (acquired) (congenital), H53.51
- Achromia parasitica, B36.0
- Achromia, congenital
- Achylia gastrica, K31.89
- Acid
- Acidemia, E87.20
- Acidity, gastric (high), K30
- Acidocytopenia
- Acidocytosis, D72.10
- Acidopenia
- Acidosis (lactic), E87.20
- Aciduria
- Acladiosis (skin), B36.0
- Aclasis, diaphyseal, Q78.6
- Acleistocardia, Q21.19
- Aclusion
- Acne, L70.9
- Acnitis (primary), A18.4
- Acosta\’s disease, T70.29
- Acoustic
- Acousticophobia, F40.298
- ACPO (acute colonic pseudo-obstruction), K59.81
- Acquired
- Acrania, Q00.0
- Acroangiodermatitis, I78.9
- Acroasphyxia, chronic, I73.89
- Acrobystitis, N47.7
- Acrocephalopolysyndactyly, Q87.0
- Acrocephalosyndactyly, Q87.0
- Acrocephaly, Q75.0
- Acrochondrohyperplasia
- Acrocyanosis, I73.89
- Acrodermatitis, L30.8
- Acrodynia
- Acromegaly, acromegalia, E22.0
- Acromelalgia, I73.81
- Acromicria, acromikria, Q79.8
- Acronyx, L60.0
- Acropachy, thyroid
- Acroparesthesia (simple) (vasomotor), I73.89
- Acropathy, thyroid
- Acrophobia, F40.241
- Acroposthitis, N47.7
- Acroscleriasis, acroscleroderma, acrosclerosis
- Acrosphacelus, I96
- Acrospiroma, eccrine
- Acrostealgia
- Acrotrophodynia
- ACTH ectopic syndrome, E24.3
- Actinic
- Actinobacillosis, actinobacillus, A28.8
- Actinomyces israelii (infection)
- Actinomycetoma (foot), B47.1
- Actinomycosis, actinomycotic, A42.9
- Actinoneuritis, G62.82
- Action, heart
- Activated protein C resistance, D68.51
- Activation
- Active
- Acute
- Acyanotic heart disease (congenital), Q24.9
- Acystia, Q64.5
- Adair-Dighton syndrome (brittle bones and blue sclera, deafness), Q78.0
- Adamantinoblastoma
- Adamantinoma
- Adamantoblastoma
- Adams-Stokes disease or syndrome (-Morgagni), I45.9
- Adaption reaction
- Addiction, F19.20
- Addison-Biermer anemia (pernicious), D51.0
- Addison-Schilder complex, E71.528
- Addisonian crisis, E27.2
- Addison\’s
- Additional
- Adduction contracture, hip or other joint
- Adenitis
- Adenoacanthoma
- Adenoameloblastoma
- Adenocarcinoid (tumor)
- Adenocarcinoma
- Adenocarcinoma-in-situ
- Adenofibroma
- Adenofibrosis
- Adenoiditis (chronic), J35.02
- Adenoids
- Adenolipoma
- Adenolipomatosis, Launois-Bensaude, E88.89
- Adenolymphoma
- Adenoma
- Adenomatosis
- Adenomatous
- Adenomyoma
- Adenomyometritis, N80.00
- Adenomyosis (uterus), N80.03
- Adenopathy (lymph gland), R59.9
- Adenosalpingitis
- Adenosarcoma
- Adenosclerosis, I88.8
- Adenosis breast (sclerosing)
- Adenovirus, as cause of disease classified elsewhere, B97.0
- Adentia (complete) (partial)
- Adherent
- Adhesions, adhesive (postinfective), K66.0
- Adiaspiromycosis, B48.8
- Adie pupil or syndrome (-Holmes)
- Adiponecrosis neonatorum, P83.88
- Adiposis
- Adiposity
- Adiposogenital dystrophy, E23.6
- Adjustment
- Administration of tPA in a different facility within the last 24 hours prior to admission to current facility (rtPA), Z92.82
- Admission (for)
- Adnexitis (suppurative)
- Adolescent X-linked adrenoleukodystrophy, E71.521
- Adrenal (gland)
- Adrenalism, tuberculous, A18.7
- Adrenalitis, adrenitis, E27.8
- Adrenarche, premature, E27.0
- Adrenocortical syndrome
- Adrenogenital syndrome, E25.9
- Adrenogenitalism, congenital, E25.0
- Adrenoleukodystrophy, E71.529
- Adrenomyeloneuropathy, E71.522
- Adventitious bursa
- Adverse effect
- Advice
- Adynamia (episodica) (hereditary) (periodic), G72.3
- Aeration lung imperfect, newborn
- Aero-otitis media, T70.0
- Aerobullosis, T70.3
- Aerocele
- Aerodermectasia
- Aerodontalgia, T70.29
- Aeroembolism, T70.3
- Aerogenes capsulatus infection, A48.0
- Aerophagy, aerophagia (psychogenic), F45.8
- Aerophobia, F40.228
- Aerosinusitis, T70.1
- Aerotitis, T70.0
- Affection
- Afibrinogenemia, D68.8
- African
- After-cataract
- Aftercare, Z51.89
- Agalactia (primary), O92.3
- Agammaglobulinemia (acquired (secondary)) (nonfamilial), D80.1
- Aganglionosis (bowel) (colon), Q43.1
- Age (old)
- Agenesis
- Ageusia, R43.2
- Agitated
- Agitation, R45.1
- Aglossia (congenital), Q38.3
- Aglossia-adactylia syndrome, Q87.0
- Aglycogenosis, E74.00
- Agnosia (body image) (other senses) (tactile), R48.1
- Agoraphobia, F40.00
- Agrammatism, R48.8
- Agranulocytopenia
- Agranulocytosis (chronic) (cyclical) (genetic) (infantile) (periodic) (pernicious), D70.9
- Agraphia (absolute), R48.8
- Ague (dumb)
- Agyria, Q04.3
- Ahumada-del Castillo syndrome, E23.0
- Aichomophobia, F40.298
- AIDS (related complex), B20
- Ailment heart
- Ailurophobia, F40.218
- AIN
- Ainhum (disease), L94.6
- AIPHI (acute idiopathic pulmonary hemorrhage in infants (over 28 days old)), R04.81
- Air
- Airplane sickness, T75.3
- Akathisia (drug-induced) (treatment-induced), G25.71
- Akinesia, R29.898
- Akinetic mutism, R41.89
- Akureyri\’s disease, G93.39
- Alactasia, congenital, E73.0
- Alagille\’s syndrome, Q44.7
- Alastrim, B03
- Albers-Schönberg syndrome, Q78.2
- Albert\’s syndrome
- Albinism, albino, E70.30
- Albinismus, E70.30
- Albright syndrome (-McCune)(-Sternberg), Q78.1
- Albuminous
- Albuminuria, albuminuric (acute) (chronic) (subacute), R80.9
- Albuminurophobia, F40.298
- Alcaptonuria, E70.29
- Alcohol, alcoholic, alcohol-induced
- Alcoholism (chronic) (without remission), F10.20
- Alder (-Reilly) anomaly or syndrome (leukocyte granulation), D72.0
- Aldosteronism, E26.9
- Aldosteronoma, D44.10
- Aldrich (-Wiskott) syndrome (eczema-thrombocytopenia), D82.0
- Alektorophobia, F40.218
- Aleppo boil, B55.1
- Aleukemic
- Aleukia
- Alexia, R48.0
- Algoneurodystrophy, M89.00
- Algophobia, F40.298
- Alienation, mental
- Alkalemia, E87.3
- Alkalosis, E87.3
- Alkaptonuria, E70.29
- Allen-Masters syndrome, N83.8
- Allergy, allergic (reaction) (to), T78.40
- Allescheriasis, B48.2
- Alligator skin disease, Q80.9
- Allocheiria, allochiria, R20.8
- Almeida\’s disease
- Alopecia (hereditaria) (seborrheica), L65.9
- Alpers\’ disease, G31.81
- Alpine sickness, T70.29
- Alport syndrome, Q87.81
- ALTE in newborn and infant (apparent life threatening event), R68.13
- Alteration, Altered (of)
- Alternating
- Altitude, high (effects)
- Aluminosis (of lung), J63.0
- Alveolitis
- Alveolus, alveolar
- Alymphocytosis, D72.810
- Alymphoplasia, thymic, D82.1
- Alzheimer\’s disease or sclerosis
- Amastia (with nipple present), Q83.8
- Amathophobia, F40.228
- Amaurosis (acquired) (congenital)
- Amaurotic idiocy (infantile) (juvenile) (late), E75.4
- Amaxophobia, F40.248
- Ambiguous genitalia, Q56.4
- Amblyopia (congenital) (ex anopsia) (partial) (suppression), H53.00-
- Ameba, amebic (histolytica)
- Amebiasis, A06.9
- Ameboma (of intestine), A06.3
- Amelia, Q73.0
- Ameloblastoma
- Amelogenesis imperfecta, K00.5
- Amenorrhea, N91.2
- Amentia
- American
- Ametropia
- AMH (asymptomatic microscopic hematuria), R31.21
- Amianthosis, J61
- Amimia, R48.8
- Amino-acid disorder, E72.9
- Aminoacidopathy, E72.9
- Aminoaciduria, E72.9
- Amnes (t)ic syndrome (post-traumatic), F04
- Amnesia, R41.3
- Amnion, amniotic
- Amnionitis
- Amok, F68.8
- Amoral traits, F60.89
- Amphetamine-induced (or other stimulant)
- Ampulla
- Amputation
- Amputee (bilateral) (old), Z89.9
- Amsterdam dwarfism, Q87.19
- Amusia, R48.8
- Amyelencephalus, amyelencephaly, Q00.0
- Amyelia, Q06.0
- Amygdalitis
- Amygdalolith, J35.8
- Amyloid heart (disease), E85.4
- Amyloidosis (generalized) (primary), E85.9
- Amylopectinosis (brancher enzyme deficiency), E74.03
- Amylophagia
- Amyoplasia congenita, Q79.8
- Amyotonia, M62.89
- Amyotrophia, amyotrophy, amyotrophic, G71.8
- Anacidity, gastric, K31.83
- Anaerosis of newborn, P28.89
- Analbuminemia, E88.09
- Analgesia
- Analphalipoproteinemia, E78.6
- Anaphylactic
- Anaphylactoid shock or reaction
- Anaphylactoid syndrome of pregnancy, O88.01-
- Anaphylaxis
- Anaplasia cervix, N87.9
- Anaplasmosis [A. phagocytophilum] (transfusion transmitted), A79.82
- Anarthria, R47.1
- Anasarca, R60.1
- Anastomosis
- Anatomical narrow angle, H40.03-
- Ancylostoma, ancylostomiasis (braziliense) (caninum) (ceylanicum) (duodenale), B76.0
- Andersen\’s disease (glycogen storage), E74.09
- Anderson-Fabry disease, E75.21
- Andes disease, T70.29
- Andrews\’ disease (bacterid), L08.89
- Androblastoma
- Androgen insensitivity syndrome, E34.50
- Androgen resistance syndrome, E34.50
- Android pelvis, Q74.2
- Androphobia, F40.290
- Anectasis, pulmonary (newborn)
- Anemia (essential) (general) (hemoglobin deficiency) (infantile) (primary) (profound), D64.9
- Anemophobia, F40.228
- Anencephalus, anencephaly, Q00.0
- Anergasia
- Anesthesia, anesthetic, R20.0
- Anetoderma (maculosum) (of), L90.8
- Aneurin deficiency, E51.9
- Aneurysm (anastomotic) (artery) (cirsoid) (diffuse) (false) (fusiform) (multiple) (saccular), I72.9
- Angelman syndrome, Q93.51
- Anger, R45.4
- Angiectasis, angiectopia, I99.8
- Angiitis, I77.6
- Angina (attack) (cardiac) (chest) (heart) (pectoris) (syndrome) (vasomotor), I20.9
- Angioblastoma
- Angiocholecystitis
- Angiocholitis, K83.09
- Angiodysgenesis spinalis, G95.19
- Angiodysplasia (cecum) (colon), K55.20
- Angioedema (allergic) (any site) (with urticaria), T78.3
- Angioendothelioma
- Angioendotheliomatosis, C85.8-
- Angiofibroma
- Angiohemophilia (A) (B)
- Angioid streaks (choroid) (macula) (retina), H35.33
- Angiokeratoma
- Angioleiomyoma
- Angiolipoma
- Angioma
- Angiomatosis, Q82.8
- Angiomyolipoma
- Angiomyoliposarcoma
- Angiomyoma
- Angiomyosarcoma
- Angiomyxoma
- Angioneurosis, F45.8
- Angioneurotic edema (allergic) (any site) (with urticaria), T78.3
- Angiopathia, angiopathy, I99.9
- Angiosarcoma
- Angiosclerosis
- Angiospasm (peripheral) (traumatic) (vessel), I73.9
- Angiospastic disease or edema, I73.9
- Angiostrongyliasis
- Anguillulosis
- Angulation
- Angulus infectiosus (lips), K13.0
- Anhedonia, R45.84
- Anhidrosis, L74.4
- Anhydration, E86.0
- Anhydremia, E86.0
- Anidrosis, L74.4
- Aniridia (congenital), Q13.1
- Anisakiasis (infection) (infestation), B81.0
- Anisakis larvae infestation, B81.0
- Aniseikonia, H52.32
- Anisocoria (pupil), H57.02
- Anisocytosis, R71.8
- Anisometropia (congenital), H52.31
- Ankle
- Ankyloblepharon (eyelid) (acquired)
- Ankyloglossia, Q38.1
- Ankylosis (fibrous) (osseous) (joint), M24.60
- Ankylostoma
- Ankylostomiasis
- Ankylurethria
- Annular
- Anoctaminopathy, G71.035
- Anodontia (complete) (partial) (vera), K00.0
- Anomaly, anomalous (congenital) (unspecified type), Q89.9
- Anomia, R48.8
- Anonychia (congenital), Q84.3
- Anophthalmos, anophthalmus (congenital) (globe), Q11.1
- Anopia, anopsia, H53.46-
- Anorchia, anorchism, anorchidism, Q55.0
- Anorexia, R63.0
- Anorgasmy, psychogenic (female), F52.31
- Anosmia, R43.0
- Anosognosia, R41.89
- Anosteoplasia, Q78.9
- Anovulatory cycle, N97.0
- Anoxemia, R09.02
- Anoxia (pathological), R09.02
- Anteflexion
- Antenatal
- Antepartum
- Anterior
- Antero-occlusion, M26.220
- Anteversion
- Anthophobia, F40.228
- Anthracosilicosis, J60
- Anthracosis (lung) (occupational), J60
- Anthrax, A22.9
- Anthropoid pelvis, Q74.2
- Anthropophobia, F40.10
- Antibodies, maternal (blood group)
- Antibody
- Anticardiolipin syndrome, D68.61
- Anticoagulant, circulating (intrinsic), D68.318
- Antidiuretic hormone syndrome, E22.2
- Antimonial cholera
- Antiphospholipid
- Antisocial personality, F60.2
- Antithrombinemia
- Antithromboplastinemia, D68.318
- Antithromboplastinogenemia, D68.318
- Antitoxin complication or reaction
- Antlophobia, F40.228
- Antritis, J32.0
- Antrum, antral
- Anuria, R34
- Anus, anal
- Anusitis, K62.89
- Anxiety, F41.9
- Aorta, aortic
- Aortectasia
- Aortitis (nonsyphilitic) (calcific), I77.6
- Apathetic thyroid storm
- Apathy, R45.3
- Apeirophobia, F40.228
- Apepsia, K30
- Aperistalsis, esophagus, K22.0
- Apertognathia, M26.29
- Apert\’s syndrome, Q87.0
- Aphagia, R13.0
- Aphakia (acquired) (postoperative), H27.0-
- Aphasia (amnestic) (global) (nominal) (semantic) (syntactic), R47.01
- Aphonia (organic), R49.1
- Aphthae, aphthous
- Apical
- Apiphobia, F40.218
- Aplasia
- Apnea, apneic (of) (spells), R06.81
- Apneumatosis, newborn, P28.0
- Apocrine metaplasia (breast)
- Apophysitis (bone)
- Apoplectiform convulsions (cerebral ischemia), I67.82
- Apoplexia, apoplexy, apoplectic
- Appearance
- Appendage
- Appendicitis (pneumococcal) (retrocecal), K37
- Appendicopathia oxyurica, B80
- Appendix, appendicular
- Appetite
- Apple peel syndrome, Q41.1
- Apprehension state, F41.1
- Apprehensiveness, abnormal, F41.9
- Approximal wear, K03.0
- Apraxia (classic) (ideational) (ideokinetic) (ideomotor) (motor) (verbal), R48.2
- Aptyalism, K11.7
- Apudoma
- Aqueous misdirection, H40.83-
- Arabicum elephantiasis
- Arachnitis
- Arachnodactyly
- Arachnoiditis (acute) (adhesive) (basal) (brain) (cerebrospinal)
- Arachnophobia, F40.210
- Arboencephalitis, Australian, A83.4
- Arborization block (heart), I45.5
- ARC (AIDS-related complex), B20
- Arc-welder\’s lung, J63.4
- Arch
- Arches
- Arcuate uterus, Q51.810
- Arcuatus uterus, Q51.810
- Arcus senilis (cornea)
- Areflexia, R29.2
- Areola
- Argentaffinoma
- Argininemia, E72.21
- Arginosuccinic aciduria, E72.22
- Argyll Robertson phenomenon, pupil or syndrome (syphilitic), A52.19
- Argyria, argyriasis
- Argyrosis, conjunctival, H11.13-
- Arhinencephaly, Q04.1
- Ariboflavinosis, E53.0
- Arm
- Arnold-Chiari disease, obstruction or syndrome (type II), Q07.00
- Aromatic amino-acid metabolism disorder, E70.9
- Arousals, confusional, G47.51
- Arrest, arrested
- Arrhenoblastoma
- Arrhythmia (auricle)(cardiac)(juvenile)(nodal)(reflex)(supraventricular)(transitory)(ventricle), I49.9
- Arrillaga-Ayerza syndrome (pulmonary sclerosis with pulmonary hypertension), I27.0
- Arsenical pigmentation, L81.8
- Arsenism
- Arterial
- Arteriofibrosis
- Arteriolar sclerosis
- Arteriolith
- Arteriolitis, I77.6
- Arteriolosclerosis
- Arterionephrosclerosis
- Arteriopathy, I77.9
- Arteriosclerosis, arteriosclerotic (diffuse) (obliterans) (of) (senile) (with calcification), I70.90
- Arteriospasm, I73.9
- Arteriovenous
- Arteritis, I77.6
- Artery, arterial
- Arthralgia (allergic)
- Arthritis, arthritic (acute) (chronic) (nonpyogenic) (subacute), M19.90
- Arthrocele
- Arthrodesis status, Z98.1
- Arthrodynia
- Arthrodysplasia, Q74.9
- Arthrofibrosis, joint
- Arthrogryposis (congenital), Q68.8
- Arthrokatadysis, M24.7
- Arthropathy, M12.9
- Arthropyosis
- Arthrosis (deformans) (degenerative) (localized), M19.90
- Arthus\’ phenomenon or reaction, T78.41
- Articular
- Articulation, reverse (teeth), M26.24
- Artificial
- Arytenoid
- Asbestosis (occupational), J61
- ASC-H (atypical squamous cells cannot exclude high grade squamous intraepithelial lesion on cytologic smear)
- ASC-US (atypical squamous cells of undetermined significance on cytologic smear)
- Ascariasis, B77.9
- Ascaridosis, ascaridiasis
- Ascaris (infection) (infestation) (lumbricoides)
- Ascending
- Aschoff\’s bodies
- Ascites (abdominal), R18.8
- Aseptic
- Asherman\’s syndrome, N85.6
- Asialia, K11.7
- Asiatic cholera
- Asimultagnosia (simultanagnosia), R48.3
- Askin\’s tumor
- Asocial personality, F60.2
- Asomatognosia, R41.4
- Aspartylglucosaminuria, E77.1
- Asperger\’s disease or syndrome, F84.5
- Aspergilloma
- Aspergillosis (with pneumonia), B44.9
- Aspergillus (flavus) (fumigatus) (infection) (terreus)
- Aspermatogenesis
- Aspermia (testis)
- Asphyxia, asphyxiation (by), R09.01
- Aspiration
- Asplenia (congenital), Q89.01
- Assam fever, B55.0
- Assault, sexual
- Assmann\’s focus NEC, A15.0
- Astasia (-abasia) (hysterical), F44.4
- Asteatosis cutis, L85.3
- Astereognosia, astereognosis, R48.1
- Asterixis, R27.8
- Asteroid hyalitis
- Asthenia, asthenic, R53.1
- Asthenopia
- Asthenospermia
- Asthma, asthmatic (bronchial) (catarrh) (spasmodic), J45.909
- Astigmatism (compound) (congenital), H52.20-
- Astraphobia, F40.220
- Astroblastoma
- Astrocytoma (cystic)
- Astroglioma
- Asymbolia, R48.8
- Asymmetry
- Asynergia, asynergy, R27.8
- Asystole (heart)
- At risk
- Ataxia, ataxy, ataxic, R27.0
- Ataxia-telangiectasia (Louis-Bar), G11.3
- Atelectasis (massive) (partial) (pressure) (pulmonary), J98.11
- Atelocardia, Q24.9
- Atelomyelia, Q06.1
- Atheroembolism
- Atheroma, atheromatous, I70.90
- Atheromatosis
- Atherosclerosis
- Athetosis (acquired), R25.8
- Athlete\’s
- Athrepsia, E41
- Athyrea (acquired)
- Atonia, atony, atonic
- Atopy
- Atransferrinemia, congenital, E88.09
- Atresia, atretic
- Atrichia, atrichosis
- Atrophia
- Atrophie blanche (en plaque) (de Milian), L95.0
- Atrophoderma, atrophodermia (of), L90.9
- Atrophy, atrophic (of)
- Attack, attacks
- Attention (to)
- Attrition
- Atypical, atypism
- Auditory
- Aujeszky\’s disease, B33.8
- Aurantiasis, cutis, E67.1
- Auricle, auricular
- Auriculotemporal syndrome, G50.8
- Austin Flint murmur (aortic insufficiency), I35.1
- Australian
- Autism, autistic (childhood) (infantile), F84.0
- Autodigestion, R68.89
- Autoerythrocyte sensitization (syndrome), D69.2
- Autographism, L50.3
- Autoimmune
- Autointoxication, R68.89
- Automatism, G93.89
- Autonomic, autonomous
- Autosensitivity, erythrocyte, D69.2
- Autosensitization, cutaneous, L30.2
- Autosome
- Autotopagnosia, R48.1
- Autotoxemia, R68.89
- Autumn
- Avellis\’ syndrome, G46.8
- Aversion
- Aviator\’s
- Avitaminosis (multiple), E56.9
- AVNRT (atrioventricular nodal re-entrant tachycardia), I47.1
- AVRT (atrioventricular nodal re-entrant tachycardia), I47.1
- Avulsion (traumatic)
- Awareness of heart beat, R00.2
- Axenfeld\’s
- Axilla, axillary
- Axonotmesis
- Ayerza\’s disease or syndrome (pulmonary artery sclerosis with pulmonary hypertension), I27.0
- Azoospermia (organic), N46.01
- Azotemia, R79.89
- Aztec ear, Q17.3
- Azygos