vancomysiini

Vancomysiini, known in English as vancomycin, is a glycopeptide antibiotic used to treat serious infections caused by Gram-positive bacteria. It binds to the D-alanyl-D-alanine terminus of peptidoglycan precursors, inhibiting transglycosylation and cell wall synthesis, which leads to bactericidal activity against susceptible organisms. It is generally not active against most Gram-negative bacteria due to the outer membrane barrier.

Indications include serious infections caused by methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus species, and certain enterococci when alternatives are unsuitable or ineffective. It is commonly used for endocarditis, osteomyelitis, septicemia, pneumonia, and complicated skin and soft tissue infections. For Clostridioides difficile infection, oral vancomycin is used for colonic disease, as it is not well absorbed from the gut when given orally.

Pharmacokinetics and administration: vancomycin is given intravenously for systemic infections and orally for intestinal infections. It has poor oral absorption when given systemically, and is primarily eliminated by the kidneys, necessitating dose adjustments in renal impairment. Therapeutic drug monitoring of trough levels is often employed to balance efficacy and toxicity, with target concentrations varying by infection type.

Adverse effects and safety: potential nephrotoxicity and ototoxicity are concerns, particularly with high trough levels or concurrent nephrotoxic drugs. Red man syndrome can occur with rapid infusion and is mitigated by slower administration. Phlebitis at the infusion site and rare hypersensitivity reactions may also occur.

Resistance: resistance can occur, most notably in enterococci (vancomycin-resistant enterococci, VRE) due to alterations of the drug's target, reducing binding and effectiveness.

History: vancomycin was discovered in the 1950s from Streptomyces orientalis and introduced clinically in the late 1950s. It remains a critical option for certain resistant Gram-positive infections, with stewardship to preserve its effectiveness.