| X linked Juvenile Retinoschisis | |
| X linked Lymphoproliferative Syndrome | |
| X- ALD | |
| X-Linked Cardioskeletal Myopathy and Neutropenia | |
| X-linked Congenital Recessive Muscle Hypotrophy with Central Nuclei | |
| X-linked Copper Deficiency | |
| X-Linked Hypophosphatemia (XLH) | |
| X-linked infantile spasm syndrome | |
| X-linked infantile spasms | |
| X-linked Mental Retardation and Macroorchidism | |
| X-Linked Mental Retardation with Hypotonia | |
| X-linked Mental Retardation-Clasped Thumb Syndrome | |
| X-linked Myotubular Myopathy | |
| X-Linked Progressive Combined Variable Immunodeficiency | |
| X-linked Recessive Centronuclear Myopathy | |
| X-linked Recessive Myotubular Myopathy | |
| X-Linked Retinoschisis | |
| X-linked Spinal and Bulbar Muscular Atrophy | |
| X-linked Spondyloepiphyseal Dysplasia | |
| X-Linked Vitamin D-Resistant Rickets | |
| X-ray, Abdominal [Medical Test] | |
| X-Ray, Arm [Medical Test] | |
| X-Ray, Back [Medical Test] | |
| X-Ray, Breast (Mammography) [Medical Test] | |
| X-Ray, Chest [Medical Test] | |
| X-ray, Dental [Medical Test] |  Top |
| X-Ray, Face [Medical Test] | |
| X-Ray, Leg [Medical Test] | |
| X-Ray, Neck [Medical Test] | |
| X-Ray, Sinus [Medical Test] | |
| X-Ray, Skull [Medical Test] | |
| X-Ray, Spine [Medical Test] | |
XA | |
| Xanthelasmoidea | |
XE | |
| Xeroderma Pigmentosum | |
| Xeroderma Pigmentosum, Variant Type, XP-V | |
| Xerodermic Idiocy | |
XL | |
| XLMR-Hypotonic Face Syndrome | |
| XLP | |
XO | |
| XO Syndrome | |
XP | |
| XP | |
XX | |
| XXXXX Syndrome | |
| XXY Syndrome | |
XY | |
| Xylose Tolerance Test [Medical Test] | |
| XYY Chromosome Pattern | |
| XYY Syndrome | |
