Rakitis

Rakitis, often referred to as rickets in many languages, is a disorder of growing bones in children characterized by defective mineralization of the growth plates. This leads to soft, weakened bones and a range of skeletal deformities. Common signs include bowing of the legs, delayed growth, dental problems, muscle weakness, and a waddling gait. In infants, features such as rachitic rosary (enlarged rib joints) and frontal bossing may be observed. The condition results from insufficient mineralization of bone matrix due to deficiencies of vitamin D, calcium, or phosphate, or from disorders that disrupt vitamin D metabolism or absorption.

Most cases worldwide stem from vitamin D deficiency, caused by limited sun exposure, inadequate dietary intake, malabsorption, or maternal vitamin D deficiency during pregnancy. Other etiologies include chronic kidney disease, certain inherited phosphate-wasting disorders, nutritional deficiencies, and medication effects that affect mineral metabolism. Genetic forms of rachitis can also occur, involving abnormalities in phosphate handling or vitamin D signaling.

Diagnosis combines clinical assessment, radiographic findings, and laboratory testing. X-rays may show metaphyseal cupping and fraying. Laboratory studies often reveal low calcium and phosphate, elevated alkaline phosphatase, secondary hyperparathyroidism, and reduced 25-hydroxyvitamin D levels. Management focuses on correcting the underlying nutrient deficiency and addressing contributing factors. Treatment typically includes vitamin D supplementation (often cholecalciferol or ergocalciferol), ensuring adequate calcium and phosphate intake, and promoting safe sunlight exposure. Severe cases may require additional phosphate supplementation or management of renal causes. With appropriate therapy, children can experience improvement in bone mineralization and growth, though established deformities may persist. Prevention emphasizes adequate vitamin D intake through diet, fortification, and sensible sun exposure, particularly in at-risk populations.