- Canavan Disease
- Cancer
- Candidiasis
- Candidiasis, Vulvovaginal
- Canker Sores
- Carbohydrate-Deficient Glycoprotein Syndrome
- Carcinoid Tumor
- Carcinoma
- Cardiomyopathy, Hypertrophic
- Carpal Tunnel Syndrome
- Cartilage Diseases
- Cat Diseases
- Cat-scratch Disease
- Cataract
- Cattle Diseases
- Celiac Disease
- Cellulitis
- Cerebellar Ataxia
- Cerebral Anoxia
- Cerebral Hemorrhage
- Cerebral Ischemia
- Cerebral Palsy
- Cerebrovascular Disorders
- Cervix Dysplasia
- Cestode infections
- Chagas Disease
- Chalazion
- Charcot-Marie Disease
- CHARGE Syndrome
- Charles Bonnet Syndrome
- Cherubism
- Chest Pain
- Chickenpox
- Chlamydia Infections
- Cholangitis
- Choledochal Cyst
- Cholelithiasis
- Cholera
- Cholesteatoma, Middle Ear
- Chondromalacia
- Chondromalacia Patellae
- Chorea
- Choroideremia
- Christmas Disease
- Chromosome 18 Abnormalities
- Churg-Strauss Syndrome
- Cleft Lip
- Clostridium Infections
- Clubfoot
- Coccidioidomycosis
- Cochlear Aqueduct
- Colonic Diseases
- Color Vision Defects
- Combat Disorders
- Charcot-Marie Disease
- CHARGE Syndrome
- Charles Bonnet Syndrome
- Cherubism
- Chest Pain
- Chickenpox
- Chlamydia Infections
- Cholangitis
- Choledochal Cyst
- Cholelithiasis
- Cholera
- Cholesteatoma, Middle Ear
- Chondromalacia
- Chondromalacia Patellae
- Chorea
- Choroideremia
- Christmas Disease
- Chromosome 18 Abnormalities
- Churg-Strauss Syndrome
- Cleft Lip
- Clostridium Infections
- Clubfoot
- Coccidioidomycosis
- Cochlear Aqueduct
- Colonic Diseases
- Color Vision Defects
- Combat Disorders
- Common Cold
- Communicative Disorders
- Compartment Syndromes
- Condylomata Acuminata
- Conjunctivitis
- Constipation
- Convulsions, Febrile
- Corneal Dystrophies
- Cornelia de Lange Syndrome
- Corticobasal Ganglionic Degeneration
- Costello Syndrome
- Coxsackievirus Infections
- Craniosynostosis
- Creutzfeldt-Jakob Syndrome
- Cri-du-Chat Syndrome
- Cross Infection
- Croup
- Cryptosporidiosis
- Cushing’s Syndrome
- Cutis Laxa
- Cyclosporiasis
- Cystic Fibrosis
- Cystinosis
- Cystitis, Interstitial
- Cytosporidiosis
- Cytomegalovirus Infections
- Common Cold
- Communicative Disorders
- Compartment Syndromes
- Condylomata Acuminata
- Conjunctivitis
- Constipation
- Convulsions, Febrile
- Corneal Dystrophies
- Cornelia de Lange Syndrome
- Corticobasal Ganglionic Degeneration
- Costello Syndrome
- Coxsackievirus Infections
- Craniosynostosis
- Creutzfeldt-Jakob Syndrome
- Cri-du-Chat Syndrome
- Cross Infection
- Croup
- Cryptosporidiosis
- Cushing’s Syndrome
- Cutis Laxa
- Cyclosporiasis
- Cystic Fibrosis
- Cystinosis
- Cystitis, Interstitial
- Cytosporidiosis
- Cytomegalovirus Infections