The civil war in Syria in recent years has caused an enormous refugee crisis [1]. Nearly 4 million people have entered Turkey. Over 90% of whom are Syrian refugees. There are 142 thousand Iraqi refugees in Turkey [2]. In our country, routine use of a daily 400 IU vitamin D supplement is recommended for infants. Vitamin D has been provided free of charge to all infants during their first year since 2005 [3]. Syrians and Iraqi refugees benefit from health services free of charge if they register. This study aimed to investigate the presence of nutritional rickets in Syrian and Iraqi refugee infants who presented to our hospital.

In this study, results of 25(OH)D vitamin levels assessment were extracted from records of Syrian and Iraqi refugee children aged from 1 to 24 months who presented to our hospital in 2017. 25(OH)D levels were examined in 77 children (54 Syrian and 23 Iraqi) for various reasons. Vitamin levels of 25(OH)D were classified as <12 ng/mL, deficiency; 12-20 ng/mL, insufficiency; and >20 ng/mL, normal [4]. Serum calcium, phosphorus, alkaline phosphatase (ALP), parathyroid hormone (PTH) of all patients were evaluated. Nutritional rickets was diagnosed with inadequate vitamin D and/or calcium levels with elevated ALP and PTH, and radiological findings of rickets [5]. Postero-anterior radiographs of left wrist or knee were done. Widening, fraying and cupping of the distal radial, ulnar and femur metaphyses were considered compatible with the radiographic findings of rickets. The demographic and laboratory findings of these children are given in Table I. The present study was approved by the Ethics Committee of our institution.

TABLE I	Clinical and Biochemical Findings in Syrian and Iraqi Refugee Children (N=77)

Infectious diseases were found in nine patients with rickets, and one child was diagnosed with type 1 diabetes mellitus. Dilated cardiomyopathy secondary to rickets was detected in one patient. The cardiac function had improved five months after treatment. Guillain-Barre　syndrome was diagnosed in one patient on evaluation of recent-onset quadriparesis. Her calcium and potassium levels were normal.

After the diagnosis of nutritional rickets, a daily oral 2000-5000 IU vitamin D treatment was started in 20 patients [6]. Stoss therapy was implemented at a dose of 150,000 IU orally in two patients. One of them had dilated cardiomyopathy with severe findings and another one had problem with compliance with the daily regimen.

Rickets treatment was completed in 11 patients. Other 11 patients with rickets did not follow up. 10 patients who completed rickets therapy had normal calcium, phosphorus, alkaline phosphatase, parathormone and vitamin D levels after treatment. Alkaline phosphatase level of PFIC-2 patient regressed to 607 IU/L but did not normalize.

Vitamin D plays an important role in cellular and humoral immunity [7]. In the present study, 41% of patients with rickets had concomitant infectious diseases of which, and nearly 80% had lower respiratory tract infection. Several studies have revealed an association between vitamin D deficiency and the development of autoimmune disorders, including multiple sclerosis, Guillaine Barre syndrome, type-1 diabetes mellitus [8-10]. However, there is no conclusive evidence that low vitamin D levels are causally associated with autoimmune diseases.

Thirteen refugee children with rickets were hospitalized and 12 of them were younger than one year. The most common complaint in children aged 1-2 years was genu varum. These findings may suggest that rickets may be the cause of these clinical illnessess or may worsen the clinical findings in these children. Increased sun exposure and intake of vitamin D fortified foods and calcium-rich foods such as milk and dairy products should be encouraged to prevent rickets in refugee children.

In conclusion, most of the patients with rickets had presented to hospital with severe clinical findings or deformity. These results seem to be only the tip of iceberg concerning vitamin D in refugee children. Moreover, stoss therapy might be considered in refugee children with rickets due to the problem about adherence to a daily regimen.

Contributors: EAA: primary responsibility for protocol development, data collecting, enrollment, outcome assessment, preliminary data analysis and writing the manuscript; HY: participated in the development of the protocol and analytical framework for the study and patient screening; EP: supervised the design and execution of the study; SS: conceptualized and designed the study, coordinated, and critically reviewed the manuscript for important intellectual content. All authors read and approved the final manuscript.　

Funding: None; Competing interest: None stated.

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