Drug resistance in intestinal tuberculosis: A reason to worry?

Emergence of drug resistance in intestinal tuberculosis (ITB) makes the treatment of this condition challenging. While there is growing evidence of multiple and extensive drug resistance in pulmonary and glandular tuberculosis (TB), literature regarding susceptibility and resistance patterns in ITB is scarce. The aim of the current paper was to study the prevalence of drug resistance in patients with ITB.

Among patients presenting to a tertiary care hospital in Mumbai between 2008 and 2016, records of all patients with ITB, whose mucosal biopsy (obtained at ileocolonoscopy) tissue culture was positive for Mycobacterium tuberculosis and in whom drug sensitivity testing was performed, were retrospectively analyzed. Sensitivity and resistance to single or multiple anti-TB drugs were noted.

A total of 43 patients were included, of whom 10 (23.2%) patients were diagnosed to have resistance to at least one first-line anti-TB drug. Resistance to isoniazid was the most common (nine patients), followed by rifampicin (six), pyrazinamide (five), streptomycin and ethionamide (four each), ethambutol, moxifloxacin and ofloxacin (three each), and p-amino salicylic acid (one). Six patients (13.9%) had multidrug-resistant TB and needed second-line anti-TB therapy as per drug sensitivity pattern. There was no patient with extensive drug-resistant TB.

Twenty-three percent of our patients with ITB tested for drug resistance had drug resistance, 13.9% being multidrug resistant and needing second-line anti-TB therapy.