- Salmonella Infections
- Salpingitis
- San Filippo Syndrome
- Sarcoidosis, Pulmonary
- Sarcoidosis
- Sarcoma
- Scabies
- Scarlet Fever
- Scheuermann’s Disease
- Schistosomiasis
- Schizophrenia
- Schmidt’s Syndrome
- Sciatica
- Scleroderma, Systemic
- Scoliosis
- Scrub Typhus
- Scurvy
- Seasonal Affective Disorder
- Self-Injurious Behavior
- Sepsis
- Severe Combined Immunodeficiency
- Sever’s Disease
- Sexually Transmitted Diseases
- Sheep and Goat Diseases
- Swine Diseases
- Syphilis, Congenital
- Shingles
- Shock
- Shprintzen Syndrome
- Shwachman Syndrome
- Shy-Drager Syndrome
- Sialorrhea
- Sinusitis
- Sjogren’s Syndrome
- Skin Diseases, Infectious
- Skin Neoplasms
- Skin Ulcer
- Sleep Disorders
- Smallpox
- Smith-Lemli-Opitz Syndrome
- Smith-Magenis Syndrome
- Soft Tissue Neoplasms
- Sotos Syndrome
- Spasmodic Dysphonia
- Spasmodic Torticollis
- Spasms, Infantile
- Speech Disorders
- Spermatic Cord Torsion
- Spina Bifida
- Spinal Cord Injuries
- Syphilis
- Syringomyelia
- Spinal Diseases
- Spinal Dysraphism
- Splenic Diseases
- Spondylitis, Ankylosing
- Sprengel’s Deformity
- Staphylococcal Infections
- Starvation
- Stein-Leventhal Syndrome
- Stevens-Johnson Syndrome
- Stickler/Marshall Syndrome
- Stiff-Man Syndrome
- Still’s Disease
- Stomatitis, Aphthous
- Strabismus
- Streptococcal Infections
- Stress
- Stress Disorders, Post-Traumatic
- Stroke
- Sturge-Weber Syndrome
- Sty
- Sudden Infant Death
- Suicide
- Supranuclear Palsy, Progressive
- Sweet’s Syndrome