Patient's question:
My baby is now 4 months and 20 days old. He always shakes his head, especially before and after sleeping. At first, we didn't think it was serious, but later, when he was playing, he was shaking violently, and that's when we realized something was wrong. We took him to the hospital, and the doctor said it might be rickets. We had an X-ray of his wrist, and the result was rickets (active phase)! Our child is very (now 21 pounds), and he was born weighing 5 pounds and 6 ounces! Is he growing too fast? We are very worried. We don't know if it can be treated, and whether it will affect his future growth. How can we prevent it in daily life?Doctor's answer:
Rickets is a common systemic disease in infancy, primarily caused by vitamin D deficiency, leading to calcium and phosphorus metabolic disorders and impaired calcification of osteoid tissue. In severe cases, it can cause skeletal deformities. Parents should take early measures to prevent the occurrence of rickets. The condition is most prevalent in patients aged 6 to 24 months.Possible rickets!
Diagnosis:
(1) General symptoms: Early signs include sleeplessness, night sweats, irritability, restlessness. As the condition progresses, symptoms may include generalized muscle weakness, hepatosplenomegaly, protruding abdomen, excessive sweating, anemia, and delayed development.
(2) Head: Softened skull, common in infants under 6 months. Applying finger pressure to the center of the parietal or occipital bone produces a bouncy, ball-like elasticity. Square skull, large anterior fontanelle with delayed closure (can persist until over 2 years of age). Delayed teething, with no milk teeth by 10 months, and weak enamel.
(3) Chest: Enlargement at the junction of ribs and costal cartilage, known as "costal beads." Pigeon chest, where the sternum protrudes forward, and the anteroposterior diameter of the chest cavity increases. Harrison groove, an indentation along the diaphragmatic attachment of the chest wall.
(4) Spine: Often hyperkyphotic (backward curvature), occasionally scoliotic.
(5) Limbs: Enlarged distal epiphyses of the ulna and radius, forming blunt, rounded bumps known as "rachitic bracelets." Lower limbs may bend, resulting in X-shaped legs, O-shaped legs, or saber legs.
Why are infants prone to rickets?
· Insufficient sunlight exposure Vitamin D is synthesized from 7-dehydrocholesterol in the skin under ultraviolet light. Insufficient sunlight exposure can lead to a deficiency in vitamin D.
· Inadequate intake Breast milk and other dairy products contain limited vitamin D. If infants do not supplement with vitamin D-rich foods in time, they are prone to rickets.
· Rapid growth Infants grow quickly, requiring a large amount of vitamin D.
· Chronic wasting diseases Conditions like chronic diarrhea, liver and biliary diseases, and kidney disorders can impair vitamin D synthesis and calcium absorption.
Key symptoms of infantile rickets:
· Neurological and mental symptoms In the early stages, infants may sweat excessively on the head during feeding and sleep, leading to localized irritation and head shaking. Frequent head shaking can cause hair loss on the occipital bone due to friction. Additionally, infants may be restless and prone to waking during sleep.
· Skeletal changes Infants aged 3–6 months may exhibit softened skulls, where pressing the central part of the parietal or occipital bone causes it to indent but rebounds when pressure is released, resembling a ball. In infants over 6 months, the distal ends of forearm and lower leg bones may show thickened bone formations, resembling bracelets. Infants over 8–9 months may develop a square skull due to excessive bone tissue accumulation under the periosteum of the frontal and parietal bones. Some infants experience delayed teething. Others may develop pigeon chest due to rib retraction, pushing the sternum outward, or funnel chest if the xiphoid processs inwards. After walking, lower limb weight-bearing can lead to O-shaped or X-shaped legs due to softened bones. Additionally, infants may have relaxed muscles and a frog-like abdomen.
Preventing rickets hinges on adequate vitamin D supplementation. The best approach is sunlight exposure, as infantile rickets is not just about calcium deficiency but also a lack of "sunlight." Ultraviolet light converts 7-dehydrocholesterol in the skin to vitamin D, promoting calcium absorption and strengthening bones. The specifics depend on the season. Due to sensitive infant skin, protection is essential. In summer, shade or umbrellas can be used, or exposure during sunrise and sunset. In spring and autumn, children should be taken outdoors frequently. In winter, outdoor activities and sunlight exposure are recommended, preferably around midday. Additionally, vitamin D supplements (400 IU/day) can be given. Premature infants should start supplementation 2 weeks after birth, while full-term infants can begin after the first month. From birth to 3 months, 800 IU/day can be used, then reduced to 400 IU/day. Calcium powder should also be added. After 2 years, as growth slows and outdoor activity increases, vitamin D supplements are generally no longer needed.