Trends and challenges in tuberculosis in a medium-sized southern European setting.

Trends in tuberculosis (TB) admissions over 40 years at the Infectious Diseases Clinic of Perugia University Hospital, Perugia, Italy, show that in the last decade non-Italian TB case admissions outweighed those of Italians, with a large number of cases from Eastern Europe (25.2%) and Africa (23.4%). Non-Italians tended to be younger and were generally new pulmonary TB cases, and drug resistance was also more common. Overall, the number of multidrug-resistant cases increased. Only one case occurred in a native-born Italian, and five of seven cases had newly diagnosed TB. In low TB incidence settings such as Perugia, Italy, TB prevention and control programmes for the foreign-born need to be reinforced.

Inhibition of beta-lactamase production in gram-positive and gram-negative strains by sub-inhibitory concentrations of nalidixic acid.

We found it of interest to try to determine a microbiological parameter for the effects that sub-inhibitory doses of a chemotherapeutic agent may have on bacteria. To this end, the antibacterial activity of nalidixic acid was analyzed and our attention was directed to evidence of the production of beta-lactamase by 60 strains. The tests carried out showed that sub-inhibitory concentrations of nalidixic acid, from 2 to 64 times lower than the MIC (minimum inhibitory concentrations), were able to inhibit production of penicillinases in the 14 strains of Staphylococcus spp. tested, while only in 7 of the 21 strains of Gram-negative bacteria. Strains from our collection of beta-lactamase producing bacteria were analyzed, and our results confirmed that nalidixic acid inhibits plasmidic and chromosomic beta-lactamases.