- Lemiere syndrome 451.89
- Lenegre's disease 426.0
- Lengthening, leg 736.81
- Lennox's syndrome (see also Epilepsy) 345.0
- Lennox-Gastaut syndrome 345.0
- Lens - see condition
- Lenticonus (anterior) (posterior) (congenital) 743.36
- Lenticular degeneration, progressive 275.1
- Lentiglobus (posterior) (congenital) 743.36
- Lentigo (congenital) 709.09
- Leonine leprosy 030.0
- Leontiasis
- Léopold-Lévi's syndrome (paroxysmal thyroid instability) 242.9
- Lepore hemoglobin syndrome 282.49
- Lepothrix 039.0
- Lepra 030.9
- Leprechaunism 259.8
- Lepromatous leprosy 030.0
- Leprosy 030.9
- Leptocytosis, hereditary 282.49
- Leptomeningitis (chronic) (circumscribed) (hemorrhagic) (nonsuppurative) (see also Meningitis) 322.9
- Leptomeningopathy (see also Meningitis) 322.9
