Teicoplanin is an antibiotic belonging to the class of glycopeptides, in use since 1986. Like its older classmate vancomycin, it inhibits protein synthesis by interfering with the synthesis of peptidoglycan, and is active on Gram-positive bacteria such as Staphilococcus spp (including MRSA), Streptococcus spp and Enterococcus spp (both faecalis and faecium). Teicoplanin is characterized by poor gastrointestinal absorption, which requires intramuscular or intravenous administration; has a binding to plasma proteins greater than 90%; and a high volume of distribution. It reaches high levels in deep tissues (bone, abdomen, lung, kidney, heart) on the contrary it has poor penetration at the central nervous system level; it is approved for the treatment of skin and soft tissue infections, osteo-articular infections, pneumonia, endocarditis, complicated urinary tract infections, peritonitis and bacteremia associated with the aforementioned clinical conditions. Furthermore, teicoplanin has a markedly long half-life (between 30 and 180h) which allows it to be administered even every 48-72h. Dose and duration of treatment should be adjusted according to the location and severity of the infection and based on patient characteristics such as renal function. The possibility of carrying out therapeutic drug monitoring (TDM) allows maintaining plasma levels adequate for the treatment of deep infections (e.g. \>20 mg/l for endocarditis) and avoiding overdose. Thanks to the possibility of administering teicoplanin on a three-weekly schedule, patient access to hospital is further reduced. The investigators therefore propose a retrospective study to evaluate the clinical effectiveness of teicoplanin therapy according to a three-weekly scheme by comparing its use in the treatment of deep infections (deep seated infections - DSIs) and superficial infections (non-deep seated infections - NDSIs).