Intravenous streptomycin use in a patient infected with high-level, gentamicin-resistant Streptococcus faecalis

OBJECTIVE: To report a case of intravenous streptomycin sulfate use in a patient infected with high-level, gentamicin-resistant Streptococcus faecalis. CASE SUMMARY: A 37-year-old woman with a history of schizoaffective disorder, diabetes insipidus possibly induced by lithium, chronic renal insufficiency, and anemia presented with a two-day history of decreased responsiveness, decreased verbalization, and tremulousness. Her hospital course was complicated by polymicrobial sepsis (S. faecalis, coagulase-negative staphylococci, Citrobacter diversus, Enterobacter aerogenes, and unidentified gram-negative bacilli #2) requiring vancomycin and gentamicin therapy. Gentamicin was discontinued after two doses because she developed acute-on-chronic renal insufficiency. Subsequent susceptibility data showed the enterococcus to be highly resistant to gentamicin. The patient deteriorated clinically when treated only with vancomycin. She remained septic with a blood pressure of 80/40 mm Hg; streptomycin was added to her regimen. We were concerned that streptomycin concentrations obtained following intramuscular administration would not be adequate because of possible hypoperfusion. Based on limited published literature, streptomycin was administered intravenously via a central intravenous catheter. DISCUSSION: A review of high-level aminoglycoside-resistant S. faecalis and treatment with intravenous streptomycin therapy are discussed. The availability and monitoring of streptomycin therapy are also described. CONCLUSIONS: Streptomycin is an antimicrobial agent that must be used with vancomycin in serious infections to eradicate high-level, gentamicin-resistant S. faecalis. Its unique administration and monitoring concerns require individual patient assessment.