A safe protocol for tuberculin test assessment in a country where BCG vaccination is mandatory

Background

Tumor necrosing factor antagonists are being widely used for the treatment of juvenile idiopathic arthritis (JIA). One concern during the treatment with anti-TNF agents is the risk of activating tuberculosis (Tbc).

Aim

We evaluated JIA patients who received anti-TNF treatment, from an eastern Mediterranean country with moderate tuberculosis frequency (official notification rate is 27/100 000).

Materials and methods

Thirty-seven JIA patients under anti-TNF treatment were enrolled to the study. Chest-X rays, purified protein derivative (PPD) tests, clinical histories and physical examinations were reviewed retrospectively. If PPD was above 10 mm in a patient with one BCG vaccination, family screening, cultures and if needed thorax computerized tomography were obtained and isoniazid prophylaxis was started for a period of 9 months. All were re-evaluated within 3 month intervals.

Results

Fifteen were females, 22 were males. Mean age was 14.2 ± 5.3 years. Mean follow up after initiation of etanercept was 12.7 ± 10.9 months. Seven patients had an initial PPD score above 10 mm. All received concomitant isoniazid treatment. Except one patient with a very severe course of systemic JIA under aggressive immunosuppressive therapy, all had normal examinations and X-rays. This one patient had a consolidation and cavitation at his right superioposterior lung zones. He is on antituberculosis treatment now without any overt clinical features of Tbc.

Conclusion

With proper initial evaluation anti-TNF treatment is safe even in countries where Tbc is moderate frequency. A 9-month isoniasid treatment is suggested for children with a ppd of >10 mm.