Antibiotic resistance of probiotic organisms and safety of probiotic dairy products

Intrinsic resistances to tetracycline, vancomycin and erythromycin are common in Lactobacillus species; however, resistance to streptomycin, clindamycin, gentamicin, oxacillin and lincosamide is also reported in these species. Resistant markers tet(W), tet(M) and erm(B) have been frequently detected in the resistant strains while van(A), lnu(A) and tet(L) have also been found in some strains of Lactobacillus. Bifidobacteria are commonly resistant to tetracycline, streptomycin, erythromycin, gentamicin and clindamycin. Resistance genes van(A), tet(L) and tet(M) are often detected in Enterococcus. Reports suggest enterococci to transfer tet(M) to E. faecalis or Listeria strains and van(A) to commercial strain of Lactobacillus acidophilus. Streptococcus species are highly resistant to tetracycline, ciprofloxacin and aztreonam and tet(M) was detected in strains of dairy origin. Clinical cases of endocarditis, septicemia, bacteremia and septic arthritis due to the species of Lactobacillus, Saccharomyces, Leuconostoc, Pediococcus and Bifidobacterium have been reported in patients with some underlying medical conditions.