Vitamin D dependent rickets: Decreased sensitivity to 1,25-dihydroxyvitamin D

A patient with vitamin D dependent rickets with decreased sensitivity to 1,25-Dihydroxyvitamin D was observed. She suffered from bone pain of two years duration beginning at 12 years of age and was found to be suffering from hypocalcemia, secondary hyperparathyroidism and osteomalacia. Laboratory findings revealed normal serum 25-hydroxyvitamin D (27 ng/ml) and markedly elevated serum 1,25-dihydroxyvitamin D (131.9 pg/ml). The hypocalcemia was refractory in spite of administration of 25,000 units of vitamin D₂, but therapy with high doses of oral 1-hydroxyvitamin D₃ resulted in significant elevation of the serum calcium level. The clinical findings and course of the patient's disease were quite different from those of other patients with vitamin D dependent rickets reported by other authors.     

Vitamin D dependent rickets type II with myelofibrosis and immune dysfunction

We present a new patient with vitamin D dependent rickets type II. A 20-month-old Arabian boy whose parents are first cousins showed florid rickets, myelofibrosis and recurrent septicaemia. In addition to absent specific binding for 1,25-dihydroxyvitamin D₃ (1,25(OH)₂D₃). 25-Hydroxyvitamin D₃-24-hydroxylase activity could not be induced in cultured fibroblasts. The patient did not respond to 99 g 1,25(OH)₂D₃ per day, but skeletal and haematological abnormalities improved with daily infusion of 100 mg/kg calcium, as serum parathyroid hormone levels fell to normal values. At the age of 7 years, he died from pneumonia. The improvement of haematological abnormalities with calcium infusions but not with 1.25(OH)₂D₃ suggests a pathogenetic relationship of myelofibrosis and hyperparathyroidism. Having antilipid A IgM antibody titres up to 110.000 after Gram negative septicaemias, the patient never produced corresponding IgG antibodies. His neutrophil chemotaxis was persistently reduced to 57%±3% of age-matched controls (P<0.028). The patient showed two pathological immune functions considered to contribute to the well-known susceptibility to infection in rickets.     

Vitamin D 依赖性佝偻病一例

患儿 ,女 ,2岁 8个月 ,因生长缓慢 2年入院。 2年前出现生长缓慢 ,身高较异卵双生的妹妹明显矮小 ,身高年增长率 <4cm/年。曾诊为“佝偻病” ,给与常规剂量的VitaminD和钙剂治疗效果不佳。近 3个月 ,患儿食欲明显减退 ,不食油腻 ,无吐泻。查体 :T 36 2℃ ,R 2 8次 /min ,P 98次 /min ,Bp90 / 6 0mmHg ,身高 77 5cm ,体重 9 5kg ,智力发育正常 ,语言发育正常 ,躯干与下肢比例正常 ,肋骨串珠 ,肋缘外翻 ,手镯、脚镯 ,轻度O型腿 ,步态轻度摇曳。心肺无异常 ,腹平软 ,肝右肋下 2cm ,脾不大。神经系统检查正常。实验室检查 :X线片示骨龄延迟…     

Vitamin D,cod-liver oil,sunlight, and rickets: a historical perspective

Rickets, a disease of vitamin D deficiency, is rarely confronted by the practicing pediatrician in the United States today. At the turn of the 20th century, rickets was rampant among the poor children living in the industrialized and polluted northern cities of the United States. With the discovery of vitamin D and the delineation of the anti-rachitic properties of cod-liver oil by the 1930s, it became possible to not only treat but also eradicate rickets in the United States. Rickets was a common disease in 17th century England. Frances Glisson's treatise on rickets published in 1650, a glorious contribution to English medicine, described the clinical and anatomic features of rickets in great detail. The exact etiology of rickets had been elusive until the 1920s. During the Glissonian era, rickets was a mysterious disease. By the late 19th and early 20th century, faulty diet or faulty environment (poor hygiene, lack of fresh air and sunshine) or lack of exercise was implicated in its etiology. Animal experiments, appreciation of folklore advocating the benefits of cod-liver oil, and the geographical association of rickets to lack of sunshine were all relevant factors in the advancement of knowledge in the conquest of this malady. In this article, the history of rickets pertaining to the discovery of vitamin D, cod-liver oil, and sunlight is reviewed.     

维生素D受体基因多态性与佝偻病易感性的研究进展

维生素D缺乏性佝偻病（简称佝偻病）是由于儿童体内维生素D不足引起钙、磷代谢紊乱,使正在生长的骨骼在成骨过程中不能正常沉着钙盐而产生的一种以骨骼病变为特征的全身慢性营养性疾病。目前认为环境因素,主要包括营养因素等是其主要致病原因,但遗传因素在其发生发展中的作用正逐渐受到重视。     

维生素D受体基因多态性与维生素D缺乏性佝偻病的关系

维生素D缺乏性佝偻病(简称佝偻病)是由于儿童体内维生素D不足引起钙、磷代谢紊乱,使正在生长的骨骼在成骨过程中不能正常沉着钙盐而产生的一种以骨骼病变为特征的全身慢性营养性疾病.目前认为环境因素及营养因素等是主要致病原因,但遗传因素在其发生发展中的作用正逐渐受到重视.维生素D是人体内钙稳态和骨代谢的主要调节因子之一,其在体内的主要活性代谢产物是1,25-(OH)2D3.维生素D受体(vitamin D receptor,VDR)是介导1,25-(OH)2D3发挥生物学效应的核内生物大分子,VDR是由VDR基因编码,因此VDR基因是研究骨代谢性疾病遗传基础的候选基因之一.文章就VDR基因多态性与佝偻病遗传易感性之间的关系作一综述.     

Vitamin D receptor polymorphism in nutritional rickets

Although the pathophysiology of rickets and especially the central role of Vitamin D in this disease has been clarified since the 1920s, it is not completely understood why rickets is still prevalant in sunny countries. Furthermore, as we understand more about rickets, it appears that rickets is a heterogeneous disorder caused by vitamin D and/or Ca deficiency. Serum 25 and 1,25 OH vitamin D levels show a wide range of variation among children with rickets and the response to treatment is also variable. These observations suggest that individual susceptibility may play a role in the development of rickets. Polymorphisms in the Vitamin D receptor (VDR) gene were postulated to be associated with bone mineral density. VDR gene polymorphism could be influential in the development of rickets in some children as well. However, data in this regard are still scarce.     

Rosai-Dorfman disease: two case reports and diagnostic role of fine-needle aspiration cytology

Rosai-Dorfman disease, or sinus histiocytosis with massive lymphadenopathy (SHML), is a rare and self-limiting benign disorder that most commonly involves the cervical lymph nodes. The authors describe two cases of SHML. Fine-needle aspiration of the lymphadenopathy was performed in both patients. Immunocytochemical and histologic features, as the evidence of emperipolesis and S100 protein positivity on immunostaining, were typical of SHML. Fine-needle aspiration cytology plays an important diagnostic role in SHML and may be conclusive in a typical clinical setting. The diagnosis of SHML should be considered in the differential diagnosis of massive, painless cervical lymphadenopathy. Long-term follow-up is necessary to observe the complete regression of the massive lymphadenopathy. However, specific therapy is available and should be limited to patients with compressive symptoms or extranodal disease.     

Vitamin D deficiency rickets: single-dose therapy versus continuous therapy

This is a comparative study of massive single dose treatment (400 000 I. U. vitamin D3, divided in 2 X 200 000 I. U. on day 1 and day 3, orally) versus continuous treatment (9600 I. U. vitamin D3-drops for 18 days) of vitamin D-deficiency rickets (VDR). To estimate the effectiveness of these two kinds of treatment the serum concentrations of calcium (Ca), phosphorus (P), alkaline phosphatase (aP), calcitriol (25-OH-CC), parathyroid hormone (PTH) and calcitonin (Ct) before and during treatment (on day 3, 7, 14, 21) were studied in 10 patients, 5 in each group, with VDR. There was no difference in the course of serum concentrations of Ca, P and aP in these two treatment-groups. The elevated PTH returned more quickly to normal range in the single dose study group. Ct-serum concentrations showed too different courses in the studied patients, therefore no comparison could be made. 25-OH-CC showed a very quick increase in the single dose-group and a slower one in the continuous treatment group the climax in both groups reached a value far over the tentative range. According to these results an unequivocal better effect of one of these two compared VDR-treatments could not be seen, what means that both treatments can be recommended.     

Vitamin D deficiency rickets at birth in Kuwait

In the present study vitamin D deficiency rickets has been diagnosed within 24 hrs. of birth. Seventy five full term, otherwise healthy newborns, weighing more than 2.5 kg were born with rachitic rosary. 25-Hydroxyvitamin D was lower than normal in 56 newborns and 15 mothers. Alkaline phosphatase was higher than normal in 26 and radiological changes suggestive of rickets were seen in the wrist X ray of only 14 newborns. Hyperphosphataemia was present in all the newborns. 1,25 dihydroxyvitamin D was markedly increased in six out of ten newborns.     

Vitamin D deficiency rickets and allegations of non-accidental injury

Vitamin D deficiency rickets has long been recognized as a cause of fractures and fracture-like appearances in young children. Often seen in the early 20th century, rickets has recently been regarded as uncommon; the radiological appearances, familiar to previous generations, may not be recognized for what they are.
This article reports four children with unexplained fractures initially attributed confidently to non-accidental injury. In each case, the later evidence of vitamin D deficiency led to a reconsideration of that diagnosis.
Conclusion:  It is important to be aware of this bone disorder in the differential diagnosis of fractures, to investigate appropriately and to recognize that the radiological appearances may be misleading. A mistaken diagnosis of abuse does real harm, not least to the child itself.     

Vitamin D deficiency rickets due to soybean milk

We describe vitamin D deficiency rickets in an infant nursed with soybean milk (not specifically designed for infants) instead of cow's milk-based infant formula. Symptoms included irritability and carpopedal spasm when crying. The infant's condition improved with nutrition by vitamin-enriched cow's milk-based infant formula, oral administration 1 alpha-hydroxy vitamin D3 and exposure to sunlight. Content analysis of the milk showed very low calcium, phosphate, magnesium and vitamin D levels compared to cow's milk-based infant milk formulas. This case highlights the unsuitability of soybean milk as the sole provider of infant nutrition and demonstrates the false perception that soybean milk is a healthy food for infants. It is necessary to be cautious about not only health claims for soybean milk, but also today's health and natural food booms. Social enlightenment and correction of such misperceptions are necessary.