- Amoral trends 301.7
- Amotio retinae (see also Detachment, retina) 361.9
- Ampulla
- Amputation
- Amputee (bilateral) (old) - see also Absence, by site, acquired V49.70
- Amusia 784.69
- Amyelencephalus 740.0
- Amyelia 742.59
- Amygdalitis - see Tonsillitis
- Amygdalolith 474.8
- Amyloid disease or degeneration 277.30
- Amyloidosis (familial) (general) (generalized) (genetic) (primary) 277.39
- Amylopectinosis (brancher enzyme deficiency) 271.0
- Amylophagia 307.52
- Amyoplasia, congenita 756.89
- Amyotonia 728.2
- Amyotrophia, amyotrophy, amyotrophic 728.2
- Anacidity, gastric 536.0
- Anaerosis of newborn 770.88
- Analbuminemia 273.8
- Analgesia (see also Anesthesia) 782.0
- Analphalipoproteinemia 272.5