[Antimicrobial prophylaxis in radical prostatectomy : single dose versus 1-day treatment]

An adequate protocol for antimicrobial prophylaxis (AMP) in radical prostatectomy (RP) has not been established. We retrospectively compared the occurrence of perioperative infection following RP between two different AMP protocols. This study included 340 cases with prostate cancer who underwent RP at our institution between January 2005 and December 2008. The 1-day group consisting of 93 cases received a second generation cephem, cefotiam, intravenously during and after the operation on the operative day. The single dose group consisting of 247 cases received cefotiam during the operation only. The incidence of surgical site infection (SSI) and remote infection (RI) was retrospectively investigated. There was no significant difference in the rate of SSI and RI occurrence between the 1-day group (2.2, 0%) and single dose group (3.6, 0.4%) (p = 0.52). The single dose protocol of AMP seems sufficient for prevention of perioperative infection in RP.

[Two cases of emphysematous pyelonephritis successfully treated by transurethral catheterization]

Cases 1 and 2 were a 84-year-old, 64-year-old female relatively. Case 2 had a history of uncontrolled diabetes mellitus. Both cases were referred to our hospital with a chief complaint of high fever. Initial diagnosis was acute pyelonephritis based on the findings of pyuria and right costovertebral angle knock pain. Abdominal computed tomography (CT) scan revealed a gas shadow in the right renal pelvis and calyx with right ureteral stone. The definitive diagnosis was emphysematous pyelonephritis (EPN). We selected transureteral catheterization into the right ureter immediately. Escherichia coli was identified from urine culture. Conservative therapy with antibiotics was also effective and general condition improved. Herein we discussed the etiology, symptomatology, choice of treatment and prognosis of emphysematous pyelonephritis. Recently CT is an effective imaging method for diagnosis at an early stage. Antibiotics therapy combined with transureteral drainage of gas-forming urolithiasis is effective as the initial conservative therapy.

[Risk factors for surgical site infection in radical cystectomy: efficacy of buried suture by absorbable thread for skin closure]

We assessed the incidence, risk factors and causative organism for surgical site infection (SSI). We reviewed the clinical charts of the consecutive 100 patients who underwent radical cystectomy from December 2003 to April 2008. All patients received intravenous prophylactic antimicrobial agent, 1 gram of cefotium hydrochloride before surgery followed by the same agent twice a day through postoperative day 3. Skin closures were carried out by interrupted sutures employing a 3-0 nylon for the first 50 patients (interrupted group), and by buried suture employing 3-0 or 4-0 braided polyglactin for the last 50 patients (buried group). SSI occurred in 13 cases (26%) with interrupted group including 8 patients with ureterocutaneoustomy and 5 patients with orthotopic ileal neobladder reconstruction. On the other hand, SSI was found in 1 patient (2%) in the buried group for whom ileal neobladder reconstruction was carried out (P= 0.021). Superficial inflectional SSI was found in 6 patients (5 patients in the interrupted group, patient in the buried group) and deep incisional SSI occurred in 5 patients in the interrupted group only. The most frequently isolated organism was Enterococcus faecalis. Univariate analysis revealed that body mass index (BMI) and the skin closure methods were significant risk factors for SSI (P<0.001, P=0.021, respectively). These 2 risk factors for SSI were also significant in multivariate analysis (P=0.003, P=0.037, respectively). These results suggested that BMI and the skin closure methods are independent risk factors in radical cystectomy. Furthermore, it may be possible to reduce the incidence of SSI by performing the buried suture for the skin closure.

Development of breakpoints of cephems for intraabdominal infections based on pharmacokinetics and pharmacodynamics in the peritoneal fluid of patients

We developed breakpoints for cephem antibacterial agents for intraabdominal infections based on pharmacokinetics (PK) and pharmacodynamics (PD) at the target site. Cefepime (CFPM), cefotiam (CTM), cefozopran (CZOP), and flomoxef (FMOX) were each administered to 8-10 patients before abdominal surgery, and venous blood and peritoneal fluid (PF) samples were obtained. The drug concentrations in plasma and PF were determined and analyzed using population pharmacokinetic modeling. Using the pharmacokinetic model parameters, a Monte Carlo simulation was conducted to estimate the probabilities of attaining the bacteriostatic and bactericidal targets (40% and 70% of the time above the minimum inhibitory concentration (T > MIC), respectively) in PF. The bacteriostatic and bactericidal breakpoints were determined as the highest MIC values at which the bacteriostatic and bactericidal probabilities in PF were > or =80%, which values varied with drug and dosing regimen. Site-specific PK-PD-based breakpoints for CFPM, CTM, CZOP, and FMOX are proposed, and should help us to select appropriate cephems and design their dosing regimens for intraabdominal infections.

The significance of the intraoperative repeated dosing of antimicrobials for preventing surgical wound infection in colorectal surgery

PURPOSE

It is widely accepted that antimicrobial prophylaxis is useful for the prevention of surgical wound infection, especially in colorectal surgery. While many reports support the finding that the first dose should be administered immediately before surgery, there is less evidence concerning the ideal timing for the second dose. The purpose of this study is to examine the significance of intraoperative repeated dosing.

METHODS

A surgical series of 131 patients with primary colorectal cancer was retrospectively analyzed for 14 parameters, including the protocols of antimicrobial administration to determine the clinical risk factors for surgical wound infection.

RESULTS

The overall surgical wound infection rate of the 131 patients was 16.0% (21/131). When the operation finished within 4 h after the first dose (n = 29), wound infection was observed in only one patient (3.4%). In a prolonged operation exceeding 4 h after the first dose, the surgical wound infection rates were 8.5% and 26.5%, respectively, for those with (n = 47) and without (n = 49) intraoperative repeated dosing, which were significantly different based on both a univariate analysis (P = 0.031) and a multivariate analysis (P = 0.0079).

CONCLUSION

Intraoperative repeated antimicrobial dosing is therefore recommended to prevent the surgical wound infection for prolonged colorectal surgery.

Camel bite: an unusual type of head injury in an infant

Small children are predisposed for animal bite wounds in the craniofacial region, because the likelihood of sustaining trunk and extremity injuries increases with height. The clinical picture of animal bite wounds is highly variable. Depending on the dental anatomy of the biting animal, such wounds may range from sharp stitch wounds to extensive lacerations with or without tissue loss. The ears and nose are injured most often because of their exposed location. Nevertheless, depressed skull fractures with injury to the dura and to the brain parenchyma are extremely rare. This case presentation describes the rare case of a craniocerebral camel bite wound (Lackmann stage IV B) in a 3-year-old girl that required immediate neurosurgical management. The neurosurgical management, choice of antibiotic, postoperative treatment, and clinical course are discussed, and background information on camel bite injuries is given.

[Efficacy of cefotiam hexetil in acute maxillary sinusitis, with a short five day vs ten day treatment]

OBJECTIVE

The aim of this multicentric, randomized, double blind study with direct individual benefit, was to compare two therapeutic regimens of cefotiam hexetil administration, 5 days vs 10 days, in acute maxillary sinusitis.

METHOD

The study was conducted in ambulatory patients treated by general practitioners according to AFSAPS (French agency for sanitary safety) guidelines for treatment of acute maxillary sinusitis. Five hundred and fifty three GPs included 1042 patients presenting with acute maxillary sinusitis in the study from December 2000 to July 2001. Patients were randomly treated with cefotiam hexetil 200 mg bid over a 5 day period followed by 5 days of placebo, or with cefotiam hexetil 200 mg bid over a 10 day period.

RESULTS

No significant difference was noted in each treatment group. Radiography performed in 72.2% of included patients confirmed the diagnosis in 78.8% of the cases. No significant difference occurred in the number and percentage of cured patients. In the ITT analysis (1018 patients) the clinical cure rates were respectively 85.5% and 85.3% in the 5 day and in the 10 day treatment groups, In the PP analysis (800 patients) the clinical cure rates were respectively 88.6% in each group. The low incidence of adverse effects (3.36%) was confirmed in both groups.

CONCLUSION

A 5 day course of cefotiam hexetil 200 mg bid is as effective as a 10 day course in the treatment of acute maxillary sinusitis in adults.

[Prophylactic antibiotics in lumbar disc surgery: analysis of 1,030 procedures]

OBJECTIVE

The purpose of this study was to investigate the efficacy of perioperative antibiotic administration in the prophylaxis of wound infection in lumbar disc surgery.

METHODS

In 1989, 541 conventional lumbar discectomies were performed to treat nucleus pulposus prolapse in 533 patients at the neurosurgical department of the Benjamin-Franklin-Hospital (Free University of Berlin). Each patient received 2 g of the antibiotic Cefotiam intravenously at induction of anesthesia. During the previous year no antibiotic was administered in 636 similar operations (in 628 Patients). Acquisition of data was performed retrospectively. After statistical stratification there remained 492 procedures in 461 patients in the prophylaxis group and 538 procedures in 475 patients in the control group. Regarding patients age, duration of the surgical procedure and distribution of individual surgeons there were no significant differences between these two groups.

RESULTS

The rate of infection was 0.2 % (n=1) in operations performed after antibiotic administration versus 2.8 % (n=15) in procedures without antibiotic prophylaxis. This difference is statistically significant (p < 0.0001).

CONCLUSION

In accordance with the reviewed literature, this study confirms that one preoperative intravenous ('single shot') administration of Cefotiam is effective in decreasing the rate of postoperative wound infections in lumbar disc surgery.

[A questionnaire survey on the theory of postoperative infection prophylaxis in otorhinolaryngology]

A questionnaire survey on postoperative infection prophylaxis was conducted to achieve the consensus on the perioperative antimicrobial use among otolaryngologists in Japan during the period of time from April to July 2000. Fifty-two out of 84 otolaryngologists replied, and the following consensus was obtained. An antimicrobial prophylaxis (AMP) agent should be chosen based on their efficacy against the pathogens expected to be contaminants, such as Staphylococcus spp., Pseudomonas aeruginosa and Bacteroides fragilis group; Use an AMP agent that achieves a bactericidal concentrations in both the serum and operating site. Use an AMP agent that has little unfavourable side effects. Newer agents should be considered as therapeutics for postoperative infections. Therapeutic antimicrobial agents having no cross-resistance to the AMP agents should be used, if postoperative infection is suspected or developed. The most commonly used agent for clean operations is cefazolin (CEZ), followed by cefotiam (CTM) and piperacillin (PIPC), in this order. For clean-contaminated operations, the most commonly used agent is CEZ, followed by flomoxef (FMOX) and CTM.

[A questionnaire survey on antimicrobial chemotherapy for acute peritonitis]

A questionnaire survey on antimicrobial chemotherapy for acute peritonitis was conducted to obtain the consensus among abdominal surgeons in Japan in the period from January to March 2002. Forty-one of the 58 surgeons replied, and the following consensus was obtained. Antibiotics should be given as soon as possible the diagnosis of infection in the abdominal cavity is established. When the perforated viscus is demonstrated at operation, giving antibiotic should be reconfirmed whether it covers organisms in the perforated site or not. The ascites obtained at operation should be sent for bacterial culture. When postoperative course is eventful, considering WBC, body temperature and CRP, the drainage fluid should be sent for culture on 4 to 7 days postoperatively. Most commonly used antibiotic for perforation of duodenal ulcer is cefotiam, and it is given 4.1 +/- 1.2 days postoperatively. Target organisms at the perforation of the lower digestive tract were E. coli, Bacteroides spp., Klebsiella pneumoniae and Enterobacter spp. Carbapenems were likely given agents for the perforation of the colon, and they were given 5.0 +/- 1.4 days postoperatively.

[Efficacy and safety of two cephalosporins in the perioperative prophylaxis in patients undergoing abdominal or vaginal hysterectomies or gynaecological laparotomies: a prospective randomized study]

The aim of this study was to compare efficacy and safety of perioperative antibiotic prophylaxis in patients undergoing abdominal or vaginal hysterectomy or gynaecological laparotomy to improve the prevention of surgical wound infections. One hundred and ninety-nine patients were prospectively randomized into two groups: the first group (n = 100) received perioperative prophylaxis using 1 g cefotiam (Spizef) and 0.5 g metronidazole (Clont) intravenously 30 min before surgery, whereas the second group (n = 99) was treated with 2 g cefoxitin (Mefoxitin) intravenously, also 30 min before surgery. The efficacy of the perioperative antibiotic prophylaxis was assessed clinically and on the basis of laboratory parameters. No wound infections were observed in 97 patients (97%) of the cefotiam-treated group and in 94 patients (94%) of the cefoxitin-treated group. No systemic postoperative infections were observed in 81% of the patients treated with cefotiam combined with metronidazole and in 85% of the patients treated with cefoxitin. The good tolerability of the drugs administered was proven in 98% of the patients treated with cefotiam and metronidazole and in 97% of the patients treated with cefoxitin. In both groups 3 patients developed nausea and/or vomiting, respectively, due to the antibiotic prophylaxis. A low infection rate after gynaecological surgery was observed. Cefotiam as a low dosage combined with metronidazole was as effective as cefoxitin. Cephalosporins of the second generation in combination with metronidazole can, therefore, be considered effective and safe drugs in the prevention of postsurgical infections.

Prospective randomized study of antibiotic prophylaxis for nonlaparotomy surgery in benign conditions

BACKGROUND

Although postoperative infections continue to be a major problem in gynecologic surgery, there is still no consensus on the efficacy of antibiotic prophylaxis.

METHODS

This prospective randomized trial was conducted to investigate the prevention of major operating site infections after nonlaparotomy surgery, with treatment regimens as follows: the first group of patients received 2 g of intravenous cefotiam dihydrochloride (CTM) on the induction of anesthesia, while the second group received 100 mg of oral cefpodoxime proxetil (CPDX- PR) twice daily, from day 0 to day 2.

RESULTS

Nineteen of the 207 patients enrolled developed postoperative infections diagnosed by our simple criteria for postoperative infection. The frequency of febrile morbidity was not significantly less in patients who received CTM (9 cases; 8.6%) as compared with those in the CPDX-PR group (10 cases; 9.8%) (p = 0.56).

CONCLUSION

The administration of oral CPDX-PR (100 mg, twice daily, for 3 days) appears to be a safe, cost-saving, convenient prophylaxis which reduces overall expense.

[Clinical efficacy of sulbactam/ampicillin in comparison with cefotiam in the treatment of elderly patients with pneumonia]

Clinical efficacy and safety of pareteral sulbactam/ampicillin (SBT/ABPC) was compared with cefotiam (CTM) in a randomized clinical trial of pneumonia in the elderly at 13 National Hospitals of Kyushu island. 37 patients received SBT/ABPC 3 g i.v., b.i.d., and 31 patients received CTM 1 g i.v., b.i.d. for 7 to 14 days. 1. 68 patients (37 for SBT/ABPC and 31 for CTM) were evaluated for safety. No statistical differences were noted in the patients' backgrounds of either group. 2. The clinical efficacy of SBT/ABPC was 96.3% (26/27 cases) while CTM was 75.2% (17/23 cases). This was found to be statistically significant (Fisher's exact test: p < 0.05). 3. 100% of evaluated cases (10 for SBT/ABPC and 4 for CTM) showed bacterial elimination. 4. No side effects were observed in the study. 5. Abnormal laboratory findings were noted in 10.8% (4/37 cases) for SBT/ABPC and 3.2% (1/31 cases) for CTM. The major adverse events were mild elevation of GOT, GPT and A1-P for SBT/ABPC, and mild platelets overproduction for CTM. No statistical differences were noted in both groups. These results are consistent with SBT/ABPC as a highly effective antibiotic in the treatment of elderly patients with pneumonia.

Severe respiratory distress following sodium oleate ingestion

CASE REPORT

Oleic acid and oleate are pulmonary toxins used to create laboratory models of acute respiratory distress syndrome, but there is little information on human toxicity. We report the intentional ingestion of 50 mL sodium oleate 20% by a 22-year-old woman with no symptoms for the first 2 days after ingestion. Her respiratory status deteriorated rapidly on day 3 progressing to acute respiratory distress syndrome (PaO2/FIO2 < 100 mm Hg) on day 4. Treatment with high-dose steroids and intensive respiratory support including high-frequency jet ventilation were associated with gradual but complete recovery by day 39. The delayed onset of symptoms suggested that the lung injury was due to the systemic circulation of oleate to the lungs rather than to direct aspiration. In oral poisoning by sodium oleate, the lung is the first and most lethally affected target organ in humans. This case demonstrates that ingestion of a relatively small amount of sodium oleate can cause delayed, progressively severe, lung injury.

Risk factors and prevention of early infection after implantation or revision of transjugular intrahepatic portosystemic shunts: results of a randomized study

The aim of this study was to evaluate the efficacy of a single dose of a second-generation cephalosporine to prevent postinterventional infection and to identify risk factors for postinterventional infection in patients receiving implantation or revision of a transjugular intrahepatic portosystemic shunt (TIPS). Eighty-four patients (105 transjugular interventions) were randomized receiving no antibiotic treatment (46 interventions) or 2 g cefotiam (56 interventions) given at the beginning of the procedure. Patients with overt infection or those receiving antibiotic treatment in the preceding two weeks were excluded. Groups were comparable with respect to biographic and medical data. Postinterventional infection was defined as an increase in WBC count (> or =15,000/microl), fever (> or =38.5 degrees C), or a positive blood culture. Infection occurred in 17% of the patients. Patients not receiving cefotiam had a slightly higher incidence of infection (20%) than patients treated with cefotiam (14%, NS). Multivariate analysis demonstrated prognostic relevance for multiple stenting and periprocedural use of a central venous line. The clinical outcome of the patients was unaffected by cefotiam treatment. In conclusion, a single dose of intrainterventional cefotiam does not prevent postinterventional infection. This may be due to the antimicrobial spectrum and short half-time of cefotiam. Strict adherence to aseptic conditions during intervention and early removal of central venous lines may reduce the rate of post interventional infection considerably. Antibiotic prophylaxis with cefotiam does not seem to be useful since it will not influence outcome and costs.

Antibacterial activity of peritoneal exudate in patients treated with 2 g cefotiam for surgical anti-microbial prophylaxis

The objective of this study was to investigate the presence of antibacterial activity in peritoneal exudate (PE) of patients treated with cefotiam (CFT). CFT (2 g) was administered as a 'single-shot' antimicrobial prophylaxis to 6 patients at the beginning of colorectal resection. Samples of PE were collected from each patient on days 1, 2 and 3 after surgery. CFT was detectable in the samples of day 1 for 5 of the 6 patients. The influence of PE on antibacterial activity of the antimicrobial drug was evaluated carrying out the MICs of CFT against Escherichia coli K-12, E. coli (ATCC 10798), Klebsiella pneumoniae (ATCC 1003), Proteus rettgeri (Sanelli) and Staphylococcus aureus (ATCC 29213) with and without the addition of PE. The presence of PE enhanced the antimicrobial activity of CFT against gram-negative strains, but not against S. aureus (ATCC 29213). These results suggest the presence of substances in PE that possess endogenous antibacterial activity. Thus, antimicrobial activity in PE cannot be predicted by evaluating pathogen sensitivity in vitro only.

[Combination use of second generation cephem and isepamicin for the treatment of post-surgical infection of the lower digestive tract]

Effects of combination use of a second generation cephem and an aminoglycoside antibiotic isepamicin (ISP), for the treatment of post-surgical infections of the lower digestive tract were examined from a laboratory and clinical perspective. Thirty-three out of total 35 cases were included in the analysis of the test, while the other 2 cases did not meet the criteria for analysis. ISP was administered in combination with one of the second generation cephems among cefotiam (CTM), cefmetazole (CMZ), or cefuroxime (CXM) for 26 cases of wound infection and 7 cases of peritonitis. The overall efficacy rate was 88%; 92% in wound infection and 71% in peritonitis individually. There was no significant difference in efficacy among different groups. Bacteriological study showed the combination use of any one of the second generation cephems and ISP was very effective in all 14 cases of infections with a single species of bacterium, the efficacy rate was 100%. It was also effective in 9 out of 10 cases with mixed infections of 2 species of bacteria (90%), but effectiveness was diminished in only 6 out of 9 cases with mixed infections of 3 species (67%). Sixty-nine strains were isolated from the 35 cases, more than half of which (44 strains) were Gram-negative; 14 strains of E. coli (20%), 13 strains of E. faecalis (13%) and 6 strains of P. aeruginosa (9%). The MIC50 and MIC90 were, respectively, 1.56 micrograms/ml and 100 micrograms/ml for ISP, 6.25 micrograms/ml and 100 micrograms/ml for CTM, 12.5 micrograms/ml and 100 micrograms/ml for CMZ, and 25 micrograms/ml and 100 micrograms/ml for CXM. The MICs in any combination uses decreased synergistically according to ISP concentration. Adverse events were observed in 3 out of 35 cases, but they were not severe. The results indicated that the combination use of a second generation cephem and ISP was useful and should be one of the choices for the treatment of post-operative infections of the lower digestive tract.

[Incidence of inflammatory placental changes in threatened premature labor with and without additional antibiotic therapy]

Considering the causal association of silent intrauterine infection and prematurity we investigated the possible effect of adjuvant antibiotic treatment of women with preterm labour on the appearance of inflammatory placental lesions. 140 patients with preterm labour in the 30 + 2 week of gestation (median; range: 17 + 2-34 + 6) without premature rupture of the membranes and detection of facultative-pathogenic micro-organisms in the vagina and/or in the canal of the cervix were enrolled in the study. 74 women were treated vaginally (polyvidone-iodine) in addition to intravenous tocolysis, 66 women were given ampicillin, cefotiam or erythromycin intravenously. After delivery the placentas were examined histologically and the frequency of inflammatory lesions was evaluated by use of 4 scores of classification. For statistical analysis the Fisher Exact- and the Wilcoxon Rank Sum Test were used. We found no differences concerning amnamnestic and perinatal parameters comparing the 2 groups of patients. With only one of the histological scores used (according to Salafia et al. [18]) we found a higher frequency of inflammatory placental lesion in the antibiotic treated group (12/66) in comparison to the vaginal treated group (4/74). Fifty patients of the antibiotics' group received the antibiotic during the last 10 days before birth. No differences in the frequency of inflammatory placental lesions were detectable in these patients when compared with the local treated group. However, we found a lower prolongation of gestation (calculated from the day of admission to the day of delivery, median: 7; range: 1-92 days) and a lower gestational age at delivery (median: 33 + 0; range: 22 + 2-39 + 6 weeks) in the patients receiving antibiotics during the last 10 days before birth in comparison to the local treated women (22; 1-138 days and 35 + 0; 23 + 4-41 + 5 weeks, respectively). There is the same incidence of inflammatory placental lesions in patients with preterm labour and facultative-pathogenic micro-organisms in the vagina and/or in the canal of the cervix who received adjuvant antibiotic treatment during pregnancy compared with patients who were treated vaginally with polyvidone-iodine.

Low-dose, single-shot perioperative antibiotic prophylaxis in colorectal surgery

Reductions of frequency of administration and dosage of antibiotic agents used in colorectal surgery may lower costs and the occurrence of adverse side effects. In a prospective randomized trial we evaluated two single-short regimens, a low dose of 1 g cefotiam against a standard dose of 2 g cefotiam, both in combination with 500 mg metronidazole. The low-dose group had twice the number of patients with wound sepsis (4 of 30) than the group receiving the standard antibiotic regimen (2 of 30). Two hours after infusion, the antibiotic concentrations in samples of serum, subcutaneous fatty tissue, and colonic wall of those patients receiving 1 g cefotiam were < 1 mg/l. The concentrations after administration of 2 g cefotiam were higher, as expected, and without any adverse side effects. In conclusion, we prefer infection prophylaxis by the standard dose of 2 g cefotiam plus 500 mg metronidazole in colorectal surgery.

[Puerperal ovarian vein thrombosis in a 14-year-old patient after cesarean section for twin pregnancy]

A case of ovarian venous thrombosis in the puerperal period after caesarean section (twin pregnancy) of a 14 year old patient is reported. After removal of the attacked vein, ovary, and fallopian tube antibiotics and heparin were given. The uterus could be maintained. The problems of diagnosis and treatment were discussed.

Synergistic enhancement of in vitro antimicrobial activity of cefmetazole and cefotiam, cefamandole or cefoperazone in combination against methicillin-sensitive and -resistant Staphylococcus aureus. II. Effect of inoculum size

The inoculum effect was studied on the activity of cefmetazole and cefotiam, cefamandole or cefoperazone alone and in combination against 9 strains of methicillin-sensitive Staphylococcus aureus (MSSA) and 20 strains of methicillin-resistant Staphylococcus aureus (MRSA) by means of the checkerboard titration method with Mueller-Hinton agar plate using 10(6) and 10(8) CFU/ml. The antimicrobial activity against MSSA and MRSA was potentiated synergistically in combination of cefmetazole and these cephalosporins either with inoculum size 10(6) or 10(8) CFU/ml. At a concentration of cephalosporins < or = 6.25 micrograms/ml, the combination effect of cefmetazole and cefotiam or cefamandole against MRSA was more potent than that of cefmetazole and cefoperazone. With a higher inoculum size the effect was reduced. Under these conditions with a low dose level of drugs, the enhancement of the activity of cefmetazole by cefotiam was least influenced by inoculum size among cephalosporins studied.

Synergistic enhancement of in vitro antimicrobial activity of cefmetazole and cefazolin, cefotiam, cefamandole or cefoperazone in combination against methicillin-sensitive and -resistant Staphylococcus aureus. I. Effect of NaCl

The in vitro antimicrobial activity of cephamycin, e.g. cefmetazole and cephalosporin, such as cefazolin, cefotiam, cefamandole and cefoperazone, alone and in combination, was studied employing 9 strains of methicillin-sensitive Staphylococcus aureus (MSSA) and 30 strains of methicillin-resistant Staphylococcus aureus (MRSA). Using the checkerboard agar dilution method, strong synergism was demonstrable in a majority of MSSA and MRSA strains for cefmetazole combined with these cephalosporins, with the minimum fractional inhibitory concentration index < or = 0.5. In the presence of a concentration < or = 6.25 micrograms/ml of these cephalosporins in Mueller-Hinton agar medium, the activity of cefmetazole against MRSA was most prominently potentiated by cefotiam, followed by cefamandole, cefazolin and cefoperazone. At a concentration of 12.5 micrograms/ml, cefotiam and cefamandole showed a similar effect in potentiation of cefmetazole activity. In hypertonic agar medium containing 4% NaCl, these synergistic combination effects were reduced. However, the activity of cefmetazole and cefamandole in combination under these conditions was influenced to a lesser extent and more potent than that of other combinations.

[Transperitoneal resorption of cefotiam in CAPD patients with and without peritonitis]

BACKGROUND

Cephalosporins of the second generation have been repeatedly recommended for the treatment of peritonitis associated with continuous ambulatory peritoneal dialysis (CAPD), because they are effective against most of the clinically relevant bacteria. In this study, we tested cefotiam, a member of this group of antibiotics, for its suitability in this indication, and determined the intraperitoneal dosage needed to achieve effective serum levels.

PATIENTS AND METHODS

IN 10 CAPD-patients with and 10 without peritonitis, cefotiam was added to the dialysis bags (2 l) over a period of seven days. Prior to initiating antibiotic treatment, a sample of dialysis fluid was submitted to bacteriological and cytological examination. During the treatment period, the bags were changed four times a day. In the first three patients 0.5 g cefotiam/bag was administered. Two to four days after initiating treatment, these patients developed nausea and occasional vomiting. Thereupon, all the other patients were given a dose of 0.5 cefotiam/bag only on the first day--a loading dose--followed by 0.25 g/bag for the next six days. Samples of blood and dialysate were obtained after 24, 48, 72, 96, 120, 144 and 168 hours. The cefotiam concentration was determined by the agar diffusion technique. Side effects were checked by clinical observation and measurement of GOT, GOP, alkaline phosphatase, gamma GT, Na, K, and creatinine together with a blood count at the beginning and end of the trial.

RESULTS

Among the peritonitis patients, Staphylococcus epidermidis and Staphylococcus pyogenes aureus were each found in four, and Pseudomonas aeruginosa in two patients. In all patients effective serum levels were reached after one day of treatment. In the following period, these levels were maintained. Serum concentrations were higher in patients with than in those without peritonitis (18 to 21 micrograms/ml and 11 to 16 micrograms/ml, respectively). The first three patients had toxic cefotiam levels of about 30 micrograms/ml. All the cases of staphylococcus-induced peritonitis were cured with this therapeutic regimen, while those with Pseudomonas aeruginosa peritonitis required additional treatment with tobramycin. Neither clinical nor chemical side effects were observed.

CONCLUSION

Using the regimen described, cefotiam is an effective and safe first-line antibiotic for the treatment of CAPD-related peritonitis.

[Puerperium after threatened premature labor--effects of infection screening in pregnancy]

Subclinical intrauterine infection is one of the causes of preterm birth. Adjuvant antibiotic treatment can improve the prolongative effects of tocolysis in patients with preterm labour. This study was conducted to evaluate the effectiveness of screening for infection and of antibiotic treatment in reducing postpartal infectious complications in patients with so called idiopathic preterm labour being treated with tocolysis intravenously. At the time of admission, we obtained cervical swabs of 138 patients for bacteriological investigation. 23 of the 37 patients with pathologic cervical colonisation were treated with antibiotics in addition to tocolysis. In women in preterm labour with pathologic cervical microbial colonisation, the frequencies of infectious complications in the puerperium were markedly increased compared to women without cervical colonisation. Adjuvant antibiotic therapy during pregnancy significantly reduced such complications. Additional antibiotic treatment of patients in idiopathic preterm labour with indicators of silent intrauterine infection seems beneficial not only for prolongation of gestation, but also for the reduction of postpartal infectious morbidity.

[Antibiotic prophylaxis for transurethral resection of the prostate--comparison of oral administration therapy with intravenous administration therapy]

To compare the prophylactic effect of oral and intravenous antibiotics against postoperative fever and urinary tract infection (UTI) after transurethral resection of the prostate (TUR-P), we conducted a multi-center prospective randomized study. The incidence of pyrexia over 38 degrees C was defined as the primary endpoint. One hundred and fifty patients with sterile urine before TUR-P were entered into this study. The patients were allocated randomly into the two arms; arm A cefotiam 4 g a day for 7 days, arm B tosufloxacin 300 mg a day for 7 days, based on the stratification into the 4 groups determined with/without preoperative indwelling catheters and with/without the history of preoperative UTI. Of these patients, 143 were eligible. We divided 124 patients without preoperative UTI and without indwelling catheters as the "low risk group", and the other 19 patients with preoperative UTI and/or with indwelling catheters as the "high risk group". In the low risk group, 9 patients out of 63 (14.3%) in arm A and 6 out of 61 (9.8%) in arm B had pyrexia during 7 postoperative days. The incidence of fever in arm B was 4.4% less than that in arm A and the 95% confidence limit was from -7% to 16%. In the high risk group, 4 out of 11 (36.4%) patients in arm A and none of 8 in arm B had fever but the difference was not significant. The incidence of post operative UTI in the low risk group on the 4 to 5, 9 to 12, 23 to 26 and 37 to 40 postoperative days was 8.3, 16.4, 25.0 and 23.9% in arm A and 6.7, 16.7, 29.6 and 36.7% in arm B, respectively. The prophylactic effect of oral administration of tosufloxacin is equivalent to that of the intravenous administration of cefotiam. The use of oral antibiotics is beneficial to reducing the cost of medication.

Antibiotic prophylaxis with two doses of cephalosporin in patients managed with internal fixation for a fracture of the hip

A prospective, randomized, double-blind study was performed to evaluate the effects of antibiotic prophylaxis on the development of a wound infection in 239 patients who had immediate stabilization of a fracture of the proximal part of the femur with a dynamic hip screw. The effects of two perioperative doses of cefotiam, given twelve hours apart, were compared with those of two doses of a placebo. Sixteen perioperative risk factors were evaluated to determine whether it was possible to identify patients who were at risk for a wound infection. All patients were followed for a minimum of six weeks. Antibiotic prophylaxis significantly reduced the prevalence of wound infection (p < 0.05): the rate of major wound infection decreased from 5 to 1 per cent and the rate of minor wound infection, from 11 to 4 per cent. The most powerful predictors of major wound infection were the duration of the operation, the interval between the accident and admission to the hospital, and the duration of postoperative urinary catheterization. The preoperative level of serum albumin and the absolute lymphocyte count were significant predictors (p < 0.05) of minor wound infection and systemic infection, respectively.

Synthesis of antibiotic-loaded hydroxyapatite beads and in vitro drug release testing

Various forms of hydroxyapatite (HAP) materials have been developed for use as bone grafts. Since the risk of local infection is associated with surgery, it seems reasonable to incorporate drugs such as antibiotics into implant materials. We therefore investigated the characteristics of drug incorporation into a spherical porous HAP bead (diameter = 8.48 mm, bulk porosity = 0.439) and its in vitro release behavior. Cefotiam (CTM) was used as a model antibiotic. Because of nonuniform pore distribution in the bead, distribution of CTM was estimated from the amounts of CTM experimentally determined at three different sites: the surface, halfway to the center, and the center of the beads. The results indicated that 90% of the drug was incorporated in the concentric outer 0.387 (radius = 1) section of the bead. CTM was released with a short lag time when the dry HAP bead was placed in water. Incorporation of CTM with egg phosphatidylcholine eliminated initial lag time and decreased the release rate of the drug from the bead. The lipid load was useful in controlling the release of CTM from the beads. In addition, to protect relatively unstable drugs from humidity and avoid contamination of drug-incorporated HAP beads an apparatus was designed with which the beads could be enclosed in vials in vacuo and under aseptic conditions on a bench-scale basis.

[Bacteriological evaluations of combination therapies with minocycline and beta-lactams for methicillin-resistant Staphylococcus aureus. I. Cefotiam plus minocycline]

Since methicillin-resistant Staphylococcus aureus (MRSA) is resistant to multiple antibiotics, only a limited number of antibacterial agents shows efficacy against this bacteria. Therefore, combination therapy is often attempted for MRSA infections. Most of the MRSA strains recently isolated, however, have been found to show very high resistance, and some of the antibiotics which had previously been effective have been failing to produce good responses in increasing numbers of patients. Thus, the drugs used for combination therapy in MRSA infections need to be reevaluated. We assessed the bacteriological efficacy of cefotiam (CTM) plus minocycline (MINO) therapy against MRSA in an in vitro system (CTM shows relatively strong antibacterial activities against MRSA with moderate resistance, and MINO shows strong antibacterial activities against highly resistant MRSA. 1. Against MINO-susceptible MRSA strains, CTM + MINO demonstrated potent antibacterial activities at MINO concentrations of MIC or sub-MIC levels, irrespective of the MIC of CTM against MRSA strains being tested. 2. Against MINO-resistant MRSA strains (strains for which MICs of MINO exceeded the upper limit of the clinically expected plasma MINO level), CTM + MINO showed no significant antibacterial activity. These results suggested that the effect of this combination was dependent on the antibacterial activity of MINO. Therefore, the usefulness of this combination in patients with MRSA infections can be predicted based on susceptibilities of involved strains to MINO. 3. The potent antibacterial effect of this combination against MINO-susceptible MRSA strains was considered to be the result of damage to the cellular membrane by MINO and the subsequent antibiotic effect of CTM.(ABSTRACT TRUNCATED AT 250 WORDS)

[Evaluation of the so-called basic cephalosporins using the serum bactericidal test]

The serum bactericidal activity (SBA) was studied one hour and four hours after intravenous administration of 1 g and 2 g cefotiam, 1.5 g cefuroxime and 2 g cefazolin to six volunteers. The 136 clinical isolates tested included Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Haemophilus influenzae. One hour after administration no significant differences in the activity against staphylococci were noted in the antibiotics tested. Four hours after administration of cefazolin 96% of the Staphylococcus aureus strains were killed at a serum dilution of 1:8, whereas only one strain was killed by cefuroxime and none by cefotiam under the same conditions. The highest SBA-titers against Haemophilus influenzae were achieved with cefotiam at a dosage of 2 g. SBA-titers against Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were higher after administration of 1 g cefotiam than after administration of 1.5 g cefuroxime and 2 g cefazolin, respectively.

Intra-operative antibiotic prophylaxis in neurosurgery. A prospective, randomized, controlled study on cefotiam

In this prospective, randomized and controlled study the effect of cefotiam for the prevention of wound infections following trepanations was investigated. The main interest was centered on the rate of post-operative bone flap infections requiring operative revision. Administration of cefotiam was randomized for patients undergoing major craniotomies. The antibiotic was administered intravenously in a single dose of 2 g with induction of anaesthesia. Only clean or clean contaminated cases were included. Excluded were contaminated cases, operations with a transnasal-transsphenoidal approach, shunt-operations and patients with any other preoperative infection or antibiotic therapy. Outpatients were excluded due to difficulties in obtaining sufficient clinical information. From originally 918 consecutive patients operated on 711 fulfilled the entry criteria. With regard to age, sex, diagnosis and the site of te trepanation, control patients (n = 355) and cefotiam treated patients (n = 356) were shown to be comparable. In the various subgroups formed for different primary diagnoses, concomitant steroidal therapy and concomitant severe internal medical diseases cefotiam treated patients and controls were comparable as well. A highly significant difference for bone flap infection could be shown with 0.3% in the cefotiam group versus 5.1% in the control group (p less than 0.001). The overall rate of post-operative deep wound infections including meningitis and abscesses was also significantly (p less than 0.005) different with 3.1% in the cefotiam versus 9.0% in the control group. Thus it was concluded that a single dose of cefotiam significantly reduces post-operative deep wound infection.

[Excretion of beta-lactam antibiotics in human parotid saliva]

We investigated the penetration of beta-lactam antibiotics into parotid saliva after intravenous administration. Neither mezlocillin nor oxacillin could be detected in parotid saliva, but cefotaxime (CTX) and cefotiam (CTM) penetrated parotid saliva very well. While salivary CTM concentrations reached peak values (9.52 +/- 3.4 mg/l) within 30 min of the end of infusion, the highest CTX concentrations in parotid saliva (5.84 +/- 2.6 mg/l) were observed after 90 min. After 300 min the salivary CTM levels were below the limit of detection, while the mean CTX concentration even 360 min after the end of infusion was 2.27 +/- 1.23 mg/l. Both CTX and CTM achieve salivary concentrations that are inhibitory against the prevailing pathogens causing suppurative parotitis, and thus promise to be effective for the treatment of this disease. Furthermore, the excretion of comparatively high concentrations of both drugs into the mouth achieves a selective decontamination of the mucosal surfaces of the upper aerodigestive tract so that they are suitable for perioperative prophylaxis in head and neck surgery.

[Clinical evaluation of the combination of carumonam and cefotiam in the treatment of complicated urinary tract infection]

The combination of carumonam (CRMN) and cefotiam (CTM), expected to have a broader spectrum of coverage in connection with urinary tract infections, was evaluated for its effectiveness and safety at the Department of Urology, Osaka University Hospital and 17 affiliated hospitals. CRMN and CTM were given together to 109 patients with complicated urinary tract infections (UTI), of whom 65 cases satisfied the "Criteria of UTI Committee for the Evaluation of Drug Efficacy in the UTI (3rd Ed.)", which was modified by adopting the midstream urine data for women. CRMN and CTM were administered by drip or one-shot infusion at a total daily dose of 4 g (equally mixed 1 g plus 1 g each, twice a day) for 5 consecutive days or longer. The overall clinical efficacy rate in the 65 cases of complicated UTI was 72%, estimated by the criteria cited above. The efficacy rate according to the infection type groupings was 72% for the 29 patients in the 1st group, 100% for the 1 patient in the 2nd group, 100% for the 7 patients in the 3rd group, 83% for the 6 patients in the 4th group, 50% for the 14 patients in the 5th group and 75% for the 8 patients in the 6th group. The disappearance rate of both urinary Gram positive cocci and Gram negative bacilli was 83.3%. Fifteen strains appeared after the treatment, only 4 of which were Gram positive cocci. Among the 109 patients treated with CRMN+CTM, no subjective side effects were recorded and the abnormalized laboratory findings observed were: eosinophilia in one patient, increases in both GPT and GOT in one patient, and lowered creatinine clearance in one patient. With a broader spectrum and safe regimen, the combination of CRMN/CTM is recommended as the first choice against complicated UTI.

Skin tissue fluid levels of cefotiam in healthy man following oral cefotiam hexetil

Cefotiam hexetil is a pro-drug of cefotiam available for oral administration. To evaluate cefotiam concentrations at the active site in skin and soft-tissue infections, drug levels in skin suction blister fluid (SBF), cantharides blister fluid (CBF) and serum were determined. Six healthy subjects received oral cefotiam 400 mg as cefotiam hexetil. On an other day 200 mg was injected intravenously. Following the oral dose, the bioavailability of cefotiam was 45.5%, and the maximum concentration in serum of 2.6 mg.l-1 was obtained at 2.1 h. Peak concentrations in both types of blister fluid (0.9 mg.l-1) were significantly lower than after the iv dose (SBF 1.4 mg.l-1, CBF 1.5 mg.l-1), and the peak levels occurred later (3.3 versus 1.5 h in CBF). Despite the delay, the extent of penetration was about 100% following either mode of administration (SBF, iv dose 112%, oral dose 117%). The cefotiam level in skin blister fluids declined significantly more slowly than the serum level. Following the oral dose, the mean terminal half life was serum 0.8 h, SBF 2.6 h and CBF 4.6 h. Cefotiam concentrations in the blister fluids were close to the MIC90 of Staphylococcus aureus, S. epidermis and H. influenzae and exceeded the MIC90 of Streptococci, E. coli and Proteus mirabilis. Thus, the oral administration of cefotiam 400 mg t.i.d. should be curative in the majority of bacterial infections of the skin and soft-tissues.

Activity of cefotiam in combination with beta-lactam antibiotics on enterobacterial hospital strains

By using checkerboard titrations the effect of cefotiam combined with different beta-lactam antibiotics on fifty strains of Enterobacteriaceae moderately susceptible (minimal inhibiting concentration greater than or equal to 8 mg/l) or resistant (minimal inhibiting concentration greater than or equal to 64 mg/l) to cefotiam was evaluated. The following compounds were tested: cefamandole, cefazolin, cefmenoxime, cefotaxime, cefotiam, ceftazidime, cefuroxime, mecillinam and piperacillin. The synergistic effect varied markedly. The combination cefotiam-mecillinam showed the highest rate of synergistic activity. Antagonism was found in 1% of the combinations.

[Perioperative short-term preventive antibiotics in head-neck surgery]

A prospective perioperative trial with cefotiam and metronidazol was carried out in 114 patients undergoing head and neck surgery. The patients were stratified in one group receiving a single-dose prophylaxis and a second group receiving a 24-hour prophylaxis. The postoperative complication rates were analysed depending on various risk factors and the size and duration of surgery. For operations of similar size the long term prophylaxis had no advantage over the one-dose prophylaxis. It is concluded that a one-dose prophylaxis appears sufficient in major head and neck cases.

[Staphylococcal endophthalmitis following squint surgery]

A 10-year-old boy was referred to the authors three days after bimedial faden operation (posterior fixation), with a purulent endophthalmitis in his right eye and visual acuity of LP. Systemic combined antibiotics "ad hoc", including cephalosporins and amikacin, were administered in combination with immunosuppressive doses of methylprednisolone after swabs had been taken for bacteriologic workup. Nine days after admission a pars plana vitrectomy was performed. Both the conjunctival swabs and the vitreous aspirate grew coagulase-negative, gram-positive cocci with high colony counts. Traction retinal detachment developed, and 30 days after the squint surgery lensectomy and silicone oil instillation had to be performed. Visual acuity 3 months after squint surgery was RE cc 0.2.

[Early complications following stapedectomy--surgical or conservative treatment?]

The incidence of sensorineural hearing loss after stapedectomy ranges from 0.6% to 5%. There is evidence that reparative granuloma is a major cause: most authors report that it requires urgent surgery, but this view is not universally accepted. This study analyses 14 stapedectomies that resulted in a sudden or gradual sensorineural hearing loss, often combined with vertigo, and presenting between 1 and 6 weeks after an initial hearing improvement. All patients were treated immediately with a combined infusion of an antibiotic, a corticosteroid and a plasma expander. The sensorineural hearing loss began to improve compared with pre-operative values 9 days later. Thus drug therapy might be sufficient in most cases of sensorineural hearing loss early after stapedectomy, and surgery can be restricted to patients with perilymph fistulae.

[Pharmacokinetic studies of cefotiam in late pregnancy]

Examining blood level values and urinary concentrations taken from pregnant women during the third trimester and nonpregnant female volunteers, the pharmacokinetic dates of cefotiam (a second generation's cephalosporin) have been evaluated. We used a computer program of an open two-compartment model for intravenous injection. We found an increase of some pharmacokinetic parameters (elimination half-life, distribution volume, clearance) during pregnancy. Because the serum levels were yet effective and nearly equal 6 hours after intravenous injection we state that it is not necessary to change the dosage and the application interval of cefotiam during pregnancy.

[Cefotiam concentration in the peritoneum in infants during surgery]

1. Supposing the hernia sac to be peritoneum, intraperitoneal transition of cefotiam (CTM) was examined on 57 cases of infantile inguinal hernia subdivided into 7 groups. 2. After one shot intravenous injection, CTM showed rapid transition into the blood and the peritoneal tissue and even at a dose of 40 mg/kg and 120 minutes later. CTM exhibited an excellent antibacterial activity considering of MIC80 against clinically isolated bacterial strains. 3. Healing by first intention of operative wounds was obtained in all of the cases given CTM without any case suggestive of postoperative infection. No clinical side effect was observed in any one of the cases.

[Evaluation of the efficacy of ceftriaxone in acute suppurative otitis media and acute exacerbation of chronic suppurative otitis media. A comparative study with cefotiam as the control]

In order to objectively evaluate the efficacy and the safety of ceftriaxone (CTRX) using once daily administration of 1 g to cases of acute suppurative otitis media and acute exacerbation of chronic suppurative otitis media, a group comparison study by the envelope method was conducted using cefotiam (CTM) as the control drug (2 g twice daily). The results obtained are summarized as follows. 1. Clinical efficacies evaluated by the committee were 71% in the CTRX group and 86% in the CTM group for acute suppurative otitis media, and 63% and 60%, respectively, for chronic suppurative otitis media. When all cases were considered both groups evidenced a clinical efficacy of 64%, and no significant difference was observed between the 2 groups. 2. Clinical efficacies evaluated by the physician in charge were 65% in the CTRX group and 86% in the CTM group for acute suppurative otitis media, and 72% and 60%, respectively, for chronic suppurative otitis media. When all cases were considered efficacies were, respectively, 70% and 64%, showing no significant difference between the 2 groups. 3. Bacteriological efficacies were 88% in the CTRX group and 86% in the CTM group for acute suppurative otitis media, and 74% and 62%, respectively, for chronic suppurative otitis media. With all cases bacterial eradication rates were, respectively, 76% and 67%. Bacterial eradication rates were always higher for the CTRX group than for the CTM group, but the difference was not significant between the 2 groups. 4. Against infections caused by Staphylococcus aureus alone, CTRX showed equal clinical and bacteriological efficacies to CTM. 5. As side effects, dermatitis, vomiting, and malaise were observed in 5 cases (4%) of the CTRX group and 3 cases (3%) of the CTM group. As clinical testing abnormalities, elevations of GOT, GPT, and Al-P, and thrombocytopenia were noted only in 3 cases (5%) of the CTRX group. Furthermore, all of these abnormalities were temporary and of moderate degree or mild, thus the safety of either drug was considered high. 6. Clinical utilities were 71% in the CTRX group and 86% in the CTM group for acute suppurative otitis media, and 72% and 62%, respectively, for chronic suppurative otitis media. When all cases were included, they were 72% and 66%, respectively, and there was no significant difference between the 2 groups. It is concluded from the above results that CTRX is a highly useful drug with once daily administration of 1 g in the treatment of suppurative otitis media.

Transperitoneal movement and pharmacokinetics of cefotiam and cefsulodin in patients on continuous ambulatory peritoneal dialysis

The kinetics of cefotiam and cefsulodin were studied in plasma and dialysate after intravenous and intraperitoneal administration of 1 g to patients undergoing continuous ambulatory peritoneal dialysis. Instillation of autologous hemoglobin as a marker permitted calculation of the cavity volume and, hence, the rate of transfer to and from the peritoneal cavity with time. The patients were divided into 4 groups. Groups 1 and 2 were intravenously given cefotiam (5 patients) and cefsulodin (4 patients), respectively. Groups 3 and 4 (5 patients each) were given cefsulodin intraperitoneally. Group 3 did not have peritonitis, while the patients in Group 4 were studied during peritonitis. Blood and dialysate samples were obtained at selected times during the 5-hour dwell and, for plasma, until 24 hours after drug administration. Pharmacokinetic analysis of the data showed that only 6.0 and 8.7% of the intravenous doses of cefotiam and cefsulodin, respectively, were recovered in the dialysate at the end of the dwell. The net amounts of cefsulodin lost from the dialysate after intraperitoneal administration were 81 and 84%, in Groups 3 and 4 respectively. The peritoneal transfer clearances (using a unidirectional clearance model), calculated after intravenous (17 +/- 10 ml/min, Group 2) and intraperitoneal (17 +/- 5 ml/min, Group 3) administrations were the same. Mass balance of cefsulodin in the body and in the dialysate after intraperitoneal administration indicated that a significant amount (40%, Group 3) of the dose is unaccounted for. One explanation for this imbalance is retention of the drug in the peritoneal lining. This hypothesis is supported by the retention being lower in the peritonitis patients (less than 20%, Group 4), for whom the linings are expected to be partially eroded.