- Pyelonephrosis (see also Pyelitis) 590.80
- Pyelophlebitis 451.89
- Pyemia, pyemic (purulent) (see also Septicemia) 038.9
- Pygopagus 759.4
- Pykno-epilepsy, pyknolepsy (idiopathic) (see also Epilepsy) 345.0
- Pyle (-Cohn) disease (craniometaphyseal dysplasia) 756.89
- Pylephlebitis (suppurative) 572.1
- Pylethrombophlebitis 572.1
- Pylethrombosis 572.1
- Pyloritis (see also Gastritis) 535.5
- Pylorospasm (reflex) 537.81
- Pylorus, pyloric - see condition
- Pyo-oophoritis (see also Salpingo-oophoritis) 614.2
- Pyo-ovarium (see also Salpingo-oophoritis) 614.2
- Pyoarthrosis - see Pyarthrosis
- Pyocele
- Pyococcal dermatitis 686.00
- Pyococcide, skin 686.00
- Pyocolpos (see also Vaginitis) 616.10
- Pyocyaneus dermatitis 686.09
- Pyocystitis (see also Cystitis) 595.9
- Pyoderma, pyodermia 686.00