- AIPHI (acute idiopathic pulmonary hemorrhage in infants (over 28 days old)) 786.31
- Air
- Airplane sickness 994.6
- Akathisia, acathisia 781.0
- Akinesia algeria 352.6
- Akiyami 100.89
- Akureyri disease (epidemic neuromyasthenia) 049.8
- Alacrima (congenital) 743.65
- Alactasia (hereditary) 271.3
- Alagille syndrome 759.89
- Alalia 784.3
- Alaninemia 270.8
- Alastrim 050.1
- Albarrán's disease (colibacilluria) 791.9
- Albers-Schönberg's disease (marble bones) 756.52
- Albert's disease 726.71
- Albinism, albino (choroid) (cutaneous) (eye) (generalized) (isolated) (ocular) (oculocutaneous) (partial) 270.2
- Albinismus 270.2
- Albright (-Martin) (-Bantam) disease (pseudohypoparathyroidism) 275.49
- Albright (-McCune) (-Sternberg) syndrome (osteitis fibrosa disseminata) 756.59
- Albuminous - see Condition
- Albuminuria, albuminuric (acute) (chronic) (subacute) 791.0
