This prospective and open trial investigated whether L. reuteri could affect the duration of diarrhoea in adults with HIV infection or AIDS. One hundred patients consecutively admitted to a Romanian university hospital or a centre for HIV treatment, 19-62 years old, and with mild to moderate dehydration were included. They were randomised to the active group given L. reuteri DSM 17938 (1×10^8 CFU/day) in addition to rehydration therapy (n=50), or the control group receiving rehydration therapy but no probiotic (n=50). Patients in both groups were also treated for the diarrhoea-causing infective microorganism if such was diagnosed (bacteria, fungi or parasites), which was the case in 74% in total. 

The duration of diarrhoea was significantly shorter in the L. reuteri group compared to the control, 2.08 days and 2.92 days, respectively (p<0.001). After one day of treatment 18/50 (36%) of the patients in the L. reuteri group were free from diarrhoea vs. 6/50 (12%) in the control group (p= 0.01), on day 2 they were 68% vs. 44% (p=0.016), and on day 3 the result was 92% vs. 70%, respectively (p=0.01).

Conclusion: L. reuteri was well tolerated, and it reduced the duration of diarrhoea significantly compared to the control group. The use of L. reuteri as an adjunct to antimicrobial treatment of different gastrointestinal infective agents optimized the treatment response and reduced discomfort in these HIV/ AIDS patients.