Persistence of Antibiotics in Blood of Patients With Acute Renal Failure. I. Tetracycline and Chlortetracycline*†

The management of patients with severe renal disease is frequently complicated by infections; these commonly involve the urinary tract, but in- fections elsewhere are not unusual. Overwhelm- ing infection, particularly with gram-negative bacteria, is often associated with shock and anuria (2) and antibiotic therapy is an integral part of the management in such cases. The persistence of a drug in the blood, once it is absorbed or after it is given systemically, depends on many factors which include: removal by the kidneys, binding to plasma proteins, sequestration in various organs and body compartments, excretion into the bile and feces, detoxification and degradation mecha- nisms and the inherent stability of the substance; most important for nearly all antibiotics, however, is their removal by the kidneys. Knowledge con- cerning the fate of antibiotics in patients with im- paired renal function is, therefore, necessary for planning therapy so that it will insure adequate blood and tissue levels without undue retention that may be harmful.