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The last decades showed a resurgence of rickets and osteomalacia in the developed countries. In this report, we present two cases of dietary rickets in Indian teenage brothers who migrated to Europe. Supplementation of calcium and vitamin D3 to their diet resulted in rapid relief of musculoskeletal symptoms.

Objective: To determine the frequency of nutritional rickets in children hospitalized with severe pneumonia., Method: This study was carried out at the department of paediatric medicine at National Institute of Child Health Karachi. It is a case series done over a period of six months from 15th November 2008 to 15th may 2009. Patients admitted (n=137) with severe pneumonia were included in the study and were investigated for presence of rickets with serum calcium, phosphorus and alkaline phosphatase. Those having low to normal calcium low phosphorus and raised alkaline phosphatase were labeled as having rickets. All data collected were entered on Performa. Children with familial, vitamin D dependent/resistant rickets, secondary rickets, and cerebral palsy or on anti convulsant therapy were excluded from this study., Results: Out of 137 patients, with severe pneumonia, 83 were male and 54 female. Frequency of nutritional rickets in children with severe pneumonia was observed in 101(74%) cases. Rickets was more common in 2 to 12 months of age, i.e., 79.8% (67/84) and in those children who were breast fed (85.3% vs. 40%). Frequency was higher in those children who were not exposed to sunlight., Conclusion: Pneumonia is a very common presentation of rickets. This study suggests that rickets may be more common in children who are breast fed and those who have less exposure to sunlight.

Reports of vitamin D-deficiency rickets and its associated morbidity continue among inadequately supplemented, dark-skinned breastfed infants. Despite the new vitamin D dietary guidelines, there remain significant numbers of unsupplemented breastfed infants. Here we report a case of subclinical vitamin D-deficiency rickets. This patient had biochemical and radiographic but not clinical evidence for rickets. We propose a new step of screening high-risk infants for subclinical rickets using wrist films paired with 25-hydroxyvitamin D levels.

Hereditary hypophosphatemic rickets with hypercalciuria (HHRH) is a new autosomal form of hypophosphatemic rickets, recently described. This disease is characterized, and differs from other forms of hereditary hypophosphatemic rickets and/or osteomalacia by increased serum levels of 1,25-dihydroxyvitamin D, hypercalciuria and complete remission of the disease on phosphate therapy alone. However, only another probable Israeli kindred, and seemingly a few sporadic cases from Europe, North America and Japan have been reported in the literature. We describe here a new kindred of Jewish Yemenite origin (unrelated to other Israeli families) with typical HHRH. Two additional members of this family suffer from a milder asymptomatic form of the disease, which presents as absorptive hypercalciuria without signs or symptoms of bone disease. It seems to us that HHRH is underdiagnosed, due to its similarity to other hypophosphatemic syndromes in clinical, radiological and most biochemical parameters. Therefore, it is recommended that urinary calcium excretion and serum 1,25-dihydroxyvitamin D concentrations be measured in every patient with hypophosphatemic rickets/and or osteomalacia before the initiation of any therapy. The correct diagnosis of HHRN is of immense therapeutic implications. Phosphate therapy alone could cause a complete remission in HHRH, while the addition of active vitamin D metabolites, as is recommended in hypophosphatemic vitamin D resistant rickets, could cause deterioration in the patient's condition.

We characterized the bone disease of transilial biopsy specimens from children with hereditary hypophosphatemic rickets with hypercalciuria (HHRH) and genetically related asymptomatic hypercalciuric subjects. All HHRH patients showed irregular mineralization fronts, markedly elevated osteoid surface and seam width, increased number of osteoid lamellae, and prolonged mineralization lag time. These findings are consistent with a mineralization defect and indicate unambiguously that the bone disease in HHRH is osteomalacia. The only abnormality seen in the asymptomatic hypercalciuric subjects was slightly extended osteoid surface. Parametric and nonparametric statistical analyses performed on a pooled sample of HHRH patients and asymptomatic hypercalciuric subjects revealed a very high inverse correlation and a tight linear relationship between serum phosphorus and osteoid parameters. Serum 1,25-dihydroxyvitamin D, which is low in other forms of hereditary hypophosphatemia and osteomalacia, is elevated in HHRH and correlated positively with osteoid parameters and the mineralization lag time. Serum alkaline phosphatase showed similar relationships. These results as well as the clinical, biochemical, and radiological remission of bone disease consequent to phosphate therapy strongly suggest that in HHRH 1) hypophosphatemia alone is sufficient to cause osteomalacia; and 2) the elevation of 1,25-dihydroxyvitamin D reflects the degree of the primary renal phosphate leak, but is not involved in the pathogenesis of the bone disease.

An unusual case of rickets associated with hypercalciuria is described. In addition to proteinuria, the patient had phosphaturia, aminoaciduria, renal glucosuria and impaired renal concentration but no renal tubular acidosis. Studies did not support the diagnosis of primary hyperparathyroidism. The findings in the patient were very similar to those in 4 previously reported cases and are suggestive of a new combination of multiple renal tubular defects.

A 14-year-old Turkish boy had severe rickets that had been clinically evident since he was 2 years of age. When he was 5 years of age, he had normal serum calcium and phosphorus levels and increased alkaline phosphatase activity. Treatment with modest dosages of vitamin D (5000 U/d for 3 weeks) resulted in hypercalcemia. At 10 years of age, high-dose vitamin D (40,000 U/d) plus phosphorus (1.1 g/d) therapy for 20 days resulted in symptomatic nephrolithiasis. When, 14 years of age, he had normocalcemia, hypophosphatemia, increased alkaline phosphatase activity, and normal circulating parathyroid hormone concentration. Levels of 25-hydroxyvitamin D were normal but those of 1,25-dihydroxyvitamin D were markedly increased. Rickets and osteopenia were evident on radiographs, and osteomalacia was present on trabecular bone obtained at biopsy. Balance study results showed increased intestinal absorption of calcium and phosphorus, hypercalciuria, and increased urinary phosphorus excretion. This patient manifests an unusual form of hypophosphatemic rickets in which hypercalciuria is a cardinal feature. In contrast with most varieties of hypophosphatemia, this disorder is characterized by appropriately increased production of 1,25-dihydroxyvitamin D in response to hypophosphatemia. It is recommended that urinary calcium excretion be assessed in all patients with hypophosphatemic rickets so that appropriate therapy will be instituted.

To compare the effects of hydrochlorothiazide (HCTZ) alone and in combination with amiloride on urinary calcium excretion we performed 14 acute studies on 7 patients with vitamin-D-induced calciuria. Each patient was studied first with HCTZ alone, and 1-32 weeks later with the same or lower dose of HCTZ combined with amiloride. Administration of HCTZ alone did not change UCaV during the 1st day of therapy, and caused a significant reduction from 44.4 +/- 28.8 to 26.0 +/- 14.4 mg/m2/24 h (p less than 0.02) on the 4th day. In contrast, combined diuretic regimen caused a significant reduction in UCaV from 36.0 +/- 16.7 to 23.6 +/- 14.4 mg/m2/24 h (p less than 0.02) on the 1st day and further reduction to 13.3 +/- 6.9 mg/m2/24 h (p less than 0.01) on the 4th day. UCaV on the 4th day was significantly lower with the HCTZ-amiloride combination (p less than 0.05). The combined therapy caused a greater reduction in FECa/FENa than HCTZ alone on the 1st day (p less than 0.02) and on the 4th day (p less than 0.01). HCTZ-induced hyperkaluria, hypokalemia and alkalosis were prevented by the addition of amiloride. In another patient, low-dose HCTZ-amiloride had a maximal dissociative effect on FECa/FENa and was more effective than HCTZ given alone in a double dose. 3 patients were treated with the low-dose HCTZ-amiloride regimen for a total of 23 months. UCaV was kept persistently low.(ABSTRACT TRUNCATED AT 250 WORDS)

In 100 infants with nutritional rickets, i.e., responsive to vitamin D therapy, we found a close inverse relationship between serum phosphorus, on the one hand, and serum alkaline phosphatase and the presence of radiological signs of rickets, on the other. There was no correlation between serum calcium and the severity of bone lesions. It is concluded that hypophosphatemia but not hypocalcemia is typical of rickets. Since hypophosphatemia and rickets can be produced experimentally by phosphate deficiency alone, we suggest our infants can be divided into two groups, one with true vitamin D deficiency that leads to hypocalcemia and no or mild bone lesions, and one with primary phosphate deficiency, resulting perhaps from a defect in phosphate transport, which leads to rickets and hypophosphatemia.