Coeliac disease as a cause of osteomalacia and rickets in the Asian immigrant population

Tumor-induced osteomalacia: a case report

Background

Tumor-induced osteomalacia is a rare, acquired paraneoplastic syndrome, including hypophosphatemia, high serum alkaline phosphatase, reduced active vitamin D, suboptimal bone mineral density, bone pain, fragility fractures, and muscle weakness.

Case presentation

We report a case of 74–year–old male of mixed ancestry with hypophosphatemia resistant to treatment despite optimal compliance, associated with profound reduction of bone mineral density and multiple nontraumatic fractures, including bilateral rib fractures, lower-thoracic (T11, T12) vertebrae, and two fractures involving the surgical and anatomical neck of the right humerus. We discuss an approach to identifying the underlying cause of hypophosphatemia associated with fragility fractures, and options for management of this rare condition.

Conclusion

Although rare, tumor-induced osteomalacia can be diagnosed if a logical stepwise approach is implemented. Surgery could be curative if the tumor is properly located and is resectable.

Routine Biochemistry in Suspected Vitamin D Deficiency

Vitamin D deficiency, which continues to be widespread amongst persons of Asian descent in the UK, is often detected from abnormal results on routine biochemistry. The aim of this study was to assess the frequency of abnormal results from routine baseline tests of serum calcium, phosphate, and alkaline phosphatase in patients who subsequently proved to have vitamin D deficiency and secondary hyperparathyroidism. A retrospective examination was undertaken to assess these baseline indices in a cohort of 84 such patients seen in Bradford-5 male; 80 of Asian descent; median age 46 years (range 16-82); serum 25-hydroxyvitamin D<10 microg/L; parathyroid hormone >54 ng/L. Calcium was normal in 55 patients (66%), phosphate in 68 (81%) and alkaline phosphatase in 24 (29%). In only 5 patients were all three indices outside the normal range. The median parathyroid hormone concentration was significantly greater in patients with abnormal routine biochemistry (145 [range 55-1662] ng/L) than in patients with normal routine biochemistry (88 [59-322] ng/L) but the median 25-hydroxyvitamin D levels did not differ (3.1 [1.3-9.9] and 3.0 [1.5-7.3] microg/L). Routine biochemistry was normal in 20% of cases. If routine biochemistry is relied upon to detect vitamin D deficiency and osteomalacia, a substantial minority of cases will be missed.

Celiac disease presenting as rickets in Saudi children

BACKGROUND AND OBJECTIVES

Rickets is commonly seen as a sign of malabsorption like celiac disease if it is not treated appropriately with vitamin D and calcium supplements. The aim of this study was to examine the frequency of diagnosis of celiac disease among children with unexplained rickets in Saudi children at a tertiary hospital setting.

DESIGN AND SETTING

Retrospective review of records of patients referred over 10 years to a pediatric gastroenterology and hepatology unit.

PATIENTS AND METHODS

The study included all patients referred for evaluation of unexplained rickets and osteomalacia and screened for celiac disease. The diagnosis of rickets was made on the basis of history, physical examination, biochemical and radiological investigations. The diagnosis of celiac disease was made based on the ESPGHAN (European Society for Pediatric Gastroenterology, Hepatology, and Nutrition) criteria.

RESULTS

Twenty-six children with a mean (SD) age of 9.5 (4.6) years (5 males, range 1-15 years) were referred for evaluation of unexplained rickets and were screened for celiac disease. The diagnosis of celiac disease based on small bowel biopsy findings was confirmed in 10 (38.4%) patients with rickets. Serological markers for celiac disease including antiendomyseal antibodies and antitissue transglutaminase antibodies were positive in all ten children.

CONCLUSION

Rickets is not an uncommon presentation of celiac disease in Saudi children and pediatricians should consider celiac disease as an underlying cause for rickets.

Routine biochemistry in suspected vitamin D deficiency

Vitamin D deficiency, which continues to be widespread amongst persons of Asian descent in the UK, is often detected from abnormal results on routine biochemistry. The aim of this study was to assess the frequency of abnormal results from routine baseline tests of serum calcium, phosphate, and alkaline phosphatase in patients who subsequently proved to have vitamin D deficiency and secondary hyperparathyroidism. A retrospective examination was undertaken to assess these baseline indices in a cohort of 84 such patients seen in Bradford-5 male; 80 of Asian descent; median age 46 years (range 16-82); serum 25-hydroxyvitamin D<10 microg/L; parathyroid hormone >54 ng/L. Calcium was normal in 55 patients (66%), phosphate in 68 (81%) and alkaline phosphatase in 24 (29%). In only 5 patients were all three indices outside the normal range. The median parathyroid hormone concentration was significantly greater in patients with abnormal routine biochemistry (145 [range 55-1662] ng/L) than in patients with normal routine biochemistry (88 [59-322] ng/L) but the median 25-hydroxyvitamin D levels did not differ (3.1 [1.3-9.9] and 3.0 [1.5-7.3] microg/L). Routine biochemistry was normal in 20% of cases. If routine biochemistry is relied upon to detect vitamin D deficiency and osteomalacia, a substantial minority of cases will be missed.

Body composition and calcium metabolism in adult treated coeliac disease

Twenty two treated adult patients with coeliac disease (aged 20-70 years) were examined. Body composition was assessed from anthropometry and directly measured by dual photon absorptiometry. Bone mineral content was measured in the spine (dual photon absorptiometry) and at two forearm sites (single photon absorptiometry). Compared with age matched healthy subjects, treated coeliac patients had lower body mass index (-5%, p less than 0.05) and lower directly measured total body fat mass (-30%, p less than 0.001). They also had decreased bone mineral content (-9 to -13%, p less than 0.01) in the spine and in the forearms. The serum concentrations of albumin, D vitamin binding protein, and iron were reduced (-6 to -22%, p less than 0.01), but otherwise blood and urine analyses were normal. We conclude that this group of treated adult coeliac patients had a reduced fat mass and bone mineral content compared with the general population.