Medical Resources :: Common Diseases :: Dietary Deficiencies & Other Conditions :: Rickets

Rickets is a disease of the bones and muscles and is due to vitamin D and calcium deficiency (view photo). 1 It was first described in the 17th century 2 and causes delayed growth, weakening and bowing of weight-bearing bones, ineffective tooth enamel formation, and muscle weakness due to low levels of calcium. One of the classic physical manifestations of rickets is frontal bossing (enlarged forehead) and box-like shape of the head. Rickets is a prevalent health problem in children all over the world, not just for children living in orphanages. It is one of the top five medical issues in children living in China (malnutrition, rickets, anemia, lead poisoning, and asthma).3 Children living in orphanages do not get enough calcium and vitamin D in their diet and they lack exposure to sunlight, decreasing the skin's ability to produce adequate vitamin D.4, 5 The muscle weakness (hypotonia) due to the lack of calcium can cause the child to appear floppy.

When the child arrives in the U.S., the child may appear developmentally delayed as a result of the decreased muscle tone and weakness of the bones due to rickets. Lack of stimulation and lack of exercise can also contribute to muscle weakness, especially muscles of the abdomen (belly). When a baby lies in the supine position (lying on the back) chronically, the abdominal (belly) muscles are weak and malnutrition can cause muscle wasting. Positioning on the belly improves this condition swiftly. Improved nutrition with vitamin D and calcium supplemented foods (formula, milk, milk products, green leafy vegetables, calcium supplemented juices) and vitamins, exposure to sunlight, and exercise rapidly improves the child's muscle tone and bone strength.

An assessment of blood chemistries including calcium, phosphorus, and alkaline phosphatase should be performed at the time of the initial screening of the child at the time of the adoption. If the chemistries are abnormal (alkaline phosphatase above 500), high dose vitamin D (Drisdol)is administered for a few months. X-rays of the knees are also recommended to evaluate the child for the classic findings of rickets (metaphyseal fraying and cupping). Repeat films are done after a few months of vitamin D therapy, to demonstrate healing rickets. Bowing of the lower extremities improves over time and the appearance of the forehead is less apparent because of weight gain, muscle mass growth, and hair growth. Rickets does not affect a child's brain or intelligence. Because teeth are composed of a matrix containing calcium and phosphorus, rickets affects the teeth as well. A dentist should be consulted regarding the integrity of the primary teeth to prevent later damage to the secondary or permanent teeth.

For more information on rickets, read Rickets in Chinese Children in the Medical Resources/Dietary Deficiencies section of this site.

Bibliography

Barness LA, Curran JS. Rickets and Vitamin D Deficiency. In Nelson WE, Behrman RE, Kliegman RM, Arvin AM eds. NelsonTextbook of Pediatrics. Philadelphia: W.B Saunders.1996: 179-183.

Smerdon GT. Daniel Whistler and the English Disease/A Translation and Biographical Note. Journal of the History of Medicine and Allied Sciences. 1950; 5: 397-415.

Chen X C, Wang WG, Yan HC, Yin TA, Xu QM. Studies on Iron Deficiency Anemia, Rickets, and Zinc Deficiency and their Prevention Among Chinese Preschool Children. Progress in Food and Nutrition Science.1992; 16: 263-277.

Aronson J E. Rickets in Chinese Children. Families with Children from China/San Francisco Bay Newsletter. 1998; 3: 34, 36.

Jenista JA. Rickets in the 1990's. Adoption/Medical News.1997; III: no. 6, 1-4.

Torres C F, Forbes G B, Decancq G H. Muscle Weakness in Infants with Rickets: Distribution, Course, and Recovery. Pediatric Neurology. 1986; 2: 95-98.