Effect of bile induced pancreatitis on tobramycin excretion in pancreatic fluid

A critical review of antibiotic prophylaxis in severe acute pancreatitis

The close association between infection and poor outcome in severe pancreatitis has led many investigators to hypothesize that antibiotic prophylaxis might reduce infection and thereby reduce mortality. However, despite this possible relationship, few studies of good quality have been performed in humans. Comprehensive searches using Medline and reviewing relevant published bibliographies of English-language human and experimental literature concerning acute pancreatitis or pancreatic tissue and antibiotic therapy or pharmacokinetics were conducted. Ample experimental evidence indicates that aminoglycosides penetrate pancreatic tissue poorly and that penetration of penicillins is variable, although the relevance of this is debatable, because most tissue that requires debridement in severe pancreatitis is necrotic peripancreatic retroperitoneal fat, not the pancreas itself. Although several animal studies suggest that antibiotic prophylaxis would be beneficial in severe pancreatitis, two recent randomized studies of intravenous antibiotics in humans provide conflicting data. There are insufficient data to recommend the use of selective digestive decontamination. Some justification exists for the use of intravenous antibiotic prophylaxis in severe pancreatitis, but the data are insufficient to mandate prophylaxis or to elevate it to the standard of care. If chosen, prophylaxis with the combination of a fluoroquinolone plus metronidazole, or monotherapy with a carbapenem antibiotic, would be most appropriate. Several other questions-including the minimum degree of severity that will benefit, the validity of endpoints other than mortality, and reduction of the need for surgical drainage-require additional trials.

Antimicrobial treatment of pancreatic infection in cats

An investigation examined the efficacy of antibiotics in a novel feline model of pancreatic infection in acute pancreatitis. Acute pancreatitis was induced in cats using an established technique. In control animals (no pancreatitis) and cats with pancreatitis, Escherichia coli (10(4) in 0.1 ml) was placed in the pancreatic duct. Reoperation was performed after 24 h in six controls and six cats with pancreatitis. E. coli was cultured from the pancreas in five control animals and five cats with pancreatitis. Reoperation was performed after 1 week in ten controls, in 11 cats with pancreatitis and in nine with pancreatitis that were treated with cefotaxime (50 mg/kg intramuscularly three times daily) started 12 h after the induction of pancreatitis and administration of E. coli. Pancreatic infection developed in eight cats with pancreatitis compared with none of the cefotaxime-treated animals and none of the controls (P < 0.05). Cefotaxime reached bactericidal levels in pancreatic tissue and juice. In conclusion, ductal administration of E. coli caused pancreatic infection only in cats with acute pancreatitis. Early administration of an appropriate antibiotic was effective in treating pancreatic infection in acute pancreatitis.

Behavior of antibiotics during human necrotizing pancreatitis

The aim of the study was to verify whether antibiotics excreted by the normal pancreas are also excreted in human necrotizing pancreatitis, reaching the tissue sites of the infection. Twelve patients suffering from acute necrotizing pancreatitis were treated with imipenem-cilastatin (0.5 g), mezlocillin (2 g), gentamicin (0.08 g), amikacin (0.5 g), pefloxacin (0.4 g), and metronidazole (0.5 g). Serum and necrotic samples were collected simultaneously at different time intervals after parenteral drug administration by computed tomography-guided needle aspiration, intraoperatively, and from surgical drainages placed during surgery. Drug concentrations were determined by microbiological and high-performance liquid chromatography assays. All antibiotics reached the necrotic tissues, but with varying degrees of penetration, this being low for aminoglycosides (13%) and high in the case of pefloxacin (89%) and metronidazole (99%). The concentrations of pefloxacin (13.0 to 23 micrograms/g) and metronidazole (8.4 micrograms/g) in the necrotic samples were distinctly higher than the MICs for the organisms most commonly isolated in this disease; the concentrations in tissue of imipenem (3.35 micrograms/g) and mezlocillin (8.0 and 15.0 micrograms/g) did not always exceed the MICs for 90% of strains tested, whereas the aminoglycoside concentrations in necrotic tissue (0.5 microgram/g) were inadequate. Repeated administration of drugs (for 3, 7, 17, and 20 days) seems to enhance penetration of pefloxacin, imipenem, and metronidazole into necrotic pancreatic tissue. The choice of antibiotics in preventing infected necrosis during necrotizing pancreatitis should be based on their antimicrobial activity, penetration rate, persistence, and therapeutic concentrations in the necrotic pancreatic area. These requisites are provided by pefloxacin and metronidazole and to a variable extent by imipenem and mezlocillin.

Antibiotics in acute pancreatitis. Current status and future directions

Infectious complications currently account for 80 percent of deaths from acute pancreatitis. The adjunctive role of antibiotics in the prevention and treatment of secondary pancreatic infections has received insufficient attention. Randomized clinical studies of effective antibiotics for prophylaxis or empiric therapy of pancreatic infections do not currently exist. In their absence, it is not known whether prophylactic antibiotics are useful in patients with acute pancreatitis. Until such studies are available, if antibiotics are to be used, their choice must be based upon indirect criteria: the ability of the antibiotic to effectively penetrate pancreatic tissue and juice, knowledge of the most common pancreatic pathogens, and the ability of the antibiotic to exceed the in vitro concentration (MIC-90) in pancreatic juice for the common pathogens. Recognition of the limited state of knowledge regarding antibiotics in acute pancreatitis may stimulate future investigations.

Blood-pancreatic juice barrier to antibiotic excretion

Antibiotics were given intravenously to dogs with chronic pancreatic fistulas, and serum and pancreatic juice levels were measured. Despite adequate serum values, gentamicin, tetracycline, clindamycin, and moxalactam did not appear in the pancreatic juice, which suggested a barrier to their excretion. In contrast, chloramphenicol reached a peak concentration in the pancreatic juice that amounted to 36 percent of the peak serum value. In the pancreatic juice, ampicillin, cefoxitin, and cefamandole reached only 5 percent of the peak serum values but were still within the therapeutic range. We have concluded that there is a blood-pancreatic juice barrier to some antibiotics, which leads to selective excretion.

Secretion of beta-lactam antibiotics in pure human pancreatic juice

The secretion of cephalothin and cefoxitin in stimulated pure pancreatic juice was studied in 13 persons after intravenous administration of antibiotics. Of all these studied, three had acute relapsing pancreatitis, five chronic pancreatitis, and five were control subjects. Antibiotic levels were measured in paired pure pancreatic juice and serum samples at fixed time intervals after administration. Cephalothin was detected in very low levels (1 to 1.8 micrograms/ml) in the pure pancreatic juice of four of the six persons studied (3 micrograms/ml). Although therapeutic levels were not obtained in stimulated pure pancreatic juice with either antibiotic, additional studies evaluating antibiotic levels in unstimulated pure pancreatic juice and in pancreatic tissue would be helpful in assessing the role of antibiotic therapy in the treatment of pancreatitis.

Excretion of cephalothin and cefamandole by the normal pancreas and in acute pancreatitis in dogs

Nine mongrel dogs were studied to evaluate the excretion of cefamandole (five dogs) and cephalothin (four dogs) in the pancreatic fluid. Each dog was studied before and after the induction of pancreatitis, with 2 weeks between studies. After intravenous administration of a 25-mg/kg dose of either cephalosporin, serum and pancreatic fluid concentrations were monitored for 6 h. Both cephalothin and cefamandole were excreted in bactericidal concentrations in the normal pancreas and in acute pancreatitis. Clearance of cefamandole (290 ml/min) and cephalothin (348 ml/min) were similar pre- and postinduction of pancreatitis. Serum albumin concentration was less during the post-pancreatitis phase compared with the prepancreatitis phase. Penetration of cephalothin was reduced in pancreatitis, whereas cefamandole penetration increased in pancreatitis.