THERE COULD BE a link between children having low vitamin D and contracting tuberculosis.

That’s according to new research that will be presented at the annual meeting of the European Society of Paediatric Infectious Diseases (ESPID) in Dublin, Ireland this week.

Re-emerging disease

Tuberculosis is a re-emerging disease in industrialised countries. A resurgence of cases has been reported in major European cities, such as Birmingham and London in the UK, Florence in Italy, Barcelona in Spain, and Brussels in Belgium.

Recently a role for vitamin D in the immune response to tuberculosis infection has been speculated.

This new study is the first study in children with a matched control group. Vitamin D levels in children with latent and active tuberculosis were evaluated and compared to healthy controls of the same age and ethnic background.

The study includes three paediatric hospitals, two in the UK and one in Italy.

The study population included 996 children screened for tuberculosis, all of whom had their vitamin D levels measured.

Of those:

• 44 children (4 per cent) had active tuberculosis
• 138 (14 per cent) had latent tuberculosis
• 814 (82 per cent) were controls.

Findings

The researchers showed that almost half (47 per cent) of the children studied had either insufficient or deficient vitamin D status, which increased to 58 per cent in the latent tuberculosis and to 75 per cent in the active tuberculosis groups.

Children with latent tuberculosis were 61 per cent more likely to have vitamin D deficiency compared to controls.

Children with active tuberculosis were 4.6 times more likely to have vitamin D deficiency compared with controls.

About two-thirds of the children studies were of African, Asian or Hispanic ethnicity, all known to be at high risk for vitamin D deficiency. Similar proportions of children with these ethnicities were in each of the three hospital study groups.

Vitamin D deficiency occurred also in the Caucasian group. It was deficient in 33 per cent of Caucasian children and insufficient in 37 per cent, and normal in 30 per cent.

The data also showed that 80 per cent of children tested in the UK had low vitamin D status compared to 44 per cent of children tested in Italy.

Dr Elisabetta Venturini says:

This difference could be mainly explained by lower sun exposure in UK with respect to Italy and probably also by the different diet within the two countries. Italy’s more Mediterranean diet is more rich in vitamin D. However, the fact that almost half the children in Italy had low vitamin D status, despite good sun exposure, should increase the awareness of this problem also in countries known to be at low risk for vitamin D deficiency.

Vitamin D supplements

Only one third of the children with low vitamin D status received vitamin D supplements.

Dr Nuria Martinez-Alier said that more definitive trials are needed.

She added that there is a need for clear evidence-based guidelines for children with low vitamin D status and tuberculosis.

The study is by Dr Elisabetta Venturini and Dr Maurizio de Martino, Anna Meyer Children’s University Hospital of Florence, Florence, Italy, Dr Vas Novelli, Great Ormond Street Hospital for Children NHS Trust, London, United Kingdom, and Dr Nuria Martinez-Alier, Evelina London Children’s Hospital, London, United Kingdom and colleagues.

Read: TB hasn’t gone away – it’s a silent killer>