Fluoroquinolones are a group of antimicrobial agents which are widely used in human and veterinary medicine. These drugs may cause interactions with other compounds. The paper describes the latest views concerning interactions between fluoroquinolones and metal cations. Simultaneous administration of fluoroquinolones with 2- and 3-valent cations causes a significant decrease in the bioavailability of these drugs due to the effect of chelating cations by carboxylate and the carbonyl group of fluoroquinolone. These interactions may result in an inefficient antimicrobial therapy and, in order to prevent this occurring, spaced dosing of fluoroquinolones and a formulation containing metal cations is recommended.
Since the discovery of Helicobacter pylori and the subsequent establishment of its key role in gastritis and peptic ulcer disease in humans, many studies have been undertaken to determine the occurrence of helicobacter in various animal species. As a result, new species of Helicobacter, including Helicobacter heilmannii, have been discovered. Helicobacter heilmannii prevalence in humans is lower than 1%. Helicobacter heilmannii has recently been distinguished into four subspecies (types). Helicobacter heilmannii has also been discovered in the stomachs of dogs, cats and pigs. Candidatus Helicobacter suis, a new species of helicobacter, was found in pigs having 80% of gastric mucosa specimens with ulcerative lesions. A homology of 99.5% has been ascertained in the 16S rRNA gene sequence between Candidatus Helicobacter suis and Helicobacter heilmannii type 1. At present the most important studies in Helicobacter infections in pigs are those relating to the possibility of the animals being naturally infected with Helicobacter pylori and, as a result, transmitting Candidatus Helicobacter suis infections to humans.