A disease of infants and children that disturbs normal bone formation (ossification), leading to failure to mineralize bone. Rickets softens bone, producing osteomalacia, and permits marked bending and distortion of bones. Other features of rickets include softness of the infant’s skull (craniotabes), enlargement of the front end of the ribs (creating the ‘rachitic rosary’), thickening of the wrists and ankles, lateral curving of the spine (scoliosis), abnormal forward’backward curving of the spine (kyphosis and lumbar lordosis), and deforming and narrowing of the pelvis. As the child begins to walk, the weight on the soft shafts of the legs results in knock-knees or, more often, bowlegs. Until the first third of the 20th century, rickets was usually due to lack of direct exposure to sunlight or to lack of vitamin D, calcium, and phosphorus, but nutritional rickets has become relatively rare in industrialized nations. In developing countries, vitamin D’deficiency rickets continues to be a problem. Rickets in developed countries is usually now due to other causes, such as disorders that create vitamin D deficiency by interfering with the absorption of vitamin D through the intestines; diseases of the liver, kidney, or other organs that impair the normal metabolic conversion and activation of vitamin D; and conditions that disrupt the normal balance in the body between calcium and phosphorus.
- Rickets, celiac
Rickets caused by failure of the intestines to absorb calcium and fat from foods.
- Rickets, hypophosphatemic
A familial form of rickets characterized by hypophosphatemia (low blood phosphate level), defective intestinal absorption of phosphate, and rickets unresponsive to vitamin D. The basic problem is decreased resorption of phosphate by the tubules in the kidney. There are two different types of the disorder that are inherited in an X-linked dominant manner. Females typically […]
- Rickets, renal
Rickets-like bone malformations that are caused by prolonged inflammation of the kidneys.
- Rickets, vitamin D resistant
A rickets-like condition caused by an inborn defect of metabolism, usually in males. Vitamin D cannot be absorbed, and so does not work to treat the illness.
- Ricketts, Howard T.
American pathologist and pioneering infectious disease expert (1871-1910) who was the first to establish the identity of the infectious organism that causes Rocky Mountain spotted fever. He and others characterized the basic epidemiologic features of the disease, including the role of tick vectors. Their studies found that Rocky Mountain spotted fever is caused by a […]