A podiatrist is an expert who deals with diseases of the feet.
A doctor - or a podiatrist.
A gastroenterologist treats diseases of the stomach.
Psychiatrist treats the diseases of your mind.
Dermatologist treats your skin diseases.
Haematology treats diseases of the blood; Vascular treats diseases of the vessels.
radiologist
A Doctor Who treats children is called a paediatrician
eat my nutsack
A Doctor who treats animal diseases and injuries is a veterinary surgeon (British English) - or Vet for short.
Such a person, who just treats feet, is a Chiropodist.
Pediatrician.
medical doctors