- CRBSI (catheter-related bloodstream infection ) 999.31
- Creaking joint 719.60
- Creeping
- Crenated tongue 529.8
- Creotoxism 005.9
- Crepitus
- Crescent or conus choroid, congenital 743.57
- Cretin, cretinism (athyrotic) (congenital) (endemic) (metabolic) (nongoitrous) (sporadic) 243
- Cretinoid degeneration 243
- Creutzfeldt-Jakob disease (syndrome) (new variant) 046.1
- Cri-du-chat syndrome 758.31
- Crib death 798.0
- Cribriform hymen 752.49
- Crigler-Najjar disease or syndrome (congenital hyperbilirubinemia) 277.4
- Crimean hemorrhagic fever 065.0
- Criminalism 301.7
- Crisis
- Crocq's disease (acrocyanosis) 443.89
- Crohn's disease (see also Enteritis, regional) 555.9
- Cronkhite-Canada syndrome 211.3
- Crooked septum, nasal 470
- Cross
