- Hydropyonephrosis (see also Pyelitis) 590.80
- Hydrorachis 742.53
- Hydrorrhea (nasal) 478.1
- Hydrosadenitis 705.83
- Hydrosalpinx (fallopian tube) (follicularis) 614.1
- Hydrothorax (double) (pleural) 511.8
- Hydroureter 593.5
- Hydroureteronephrosis (see also Hydronephrosis) 591
- Hydrourethra 599.84
- Hydroxykynureninuria 270.2
- Hydroxyprolinemia 270.8
- Hydroxyprolinuria 270.8
- Hygroma (congenital) (cystic) (M9173/0) 228.1
- Hymen - see condition
- Hymenolepiasis (diminuta) (infection) (infestation) (nana) 123.6
- Hymenolepsis (diminuta) (infection) (infestation) (nana) 123.6
- Hypalgesia (see also Disturbance, sensation) 782.0
- Hyper-TBG-nemia 246.8
- Hyperabduction syndrome 447.8
- Hyperacidity, gastric 536.8
- Hyperactive, hyperactivity
- Hyperacusis 388.42
