Rifampicin-soaked silver polyester versus expanded polytetrafluoro-ethylene grafts for in situ replacement of infected grafts in a porcine randomised controlled trial.

BACKGROUND: To compare the efficacy of in situ replacement with rifampicin-soaked silver-coated polyester (RSSCP) to that of expanded polytetrafluoroethylene (ePTFE) graft replacements in a porcine model for early aortic prosthetic vascular graft infection (PVGI). MATERIAL AND METHODS: Sixty pigs received polyester or silver-coated grafts with an 8 mm diameter implanted end-to-end in the infrarenal aorta, and the grafts were inoculated with approximately 10(6)Staphylococcus aureus. All developed S. aureus PVGI. Two weeks later, the 52 surviving pigs were randomised to undergo in situ graft replacement with ePTFE or RSSCP grafts followed by oral administration of 300 mg rifampicin and 750 mg ciprofloxacin twice a day, postoperatively. After three weeks, all pigs were sacrificed. In situ perigraft swabs and graft material were analysed for S. aureus quantitatively. RESULTS: Only one out of 25 RSSCP grafts were infected with S. aureus, whereas 15 of 27 ePTFE grafts were infected after 3 weeks (OR = 0.022, 95% CI: 0.002, 0.219, P = 0.001). CONCLUSIONS: In situ replacement with RSSCP grafts and oral rifampicin plus ciprofloxacin is more efficiency in eradicating S. aureus PVGI than ePTFE grafts treated with same oral antibiotics in a porcine aortic PVGI model.

Prevention of primary vascular graft infection with silver-coated polyester graft in a porcine model.

OBJECTIVES: To evaluate the efficacy of a silver-coated vascular polyester graft in the prevention of graft infection after inoculation with Staphylococcus aureus in a porcine model. MATERIAL AND METHODS: Eighty-four pigs were randomly selected 1:1 to receive a silver-coated or non-silver-coated 8-mm-wide polyester graft implanted end-to-end in the infrarenal aorta. At the end of implantation, 10(6) colony forming units (CFUs) S. aureus in 0.3ml suspension were inoculated directly on the graft surface. Blood samples assayed for white blood corpuscles (WBCs) and C-reactive protein (CRP) were taken before implantation and on the postoperative days 2, 5, 7, 11 and 14. Two weeks after implantation, the perigraft swabs were analysed for S. aureus or contaminants. CFUs of S. aureus were quantified and logarithmised. Student's t-tests, repeated measurement analysis of variance (ANOVA) and chi-square test were employed to compare the two grafts. RESULTS: All pigs developed graft infection. There were no statistically significant differences between the silver-coated and non-silver-coated grafts in the quantity of S. aureus, macroscopic signs of infection and postoperative changes in the temperature, WBC and CRP. CONCLUSIONS: Silver-coated polyester grafts failed to prevent graft infections after inoculation with 10(6)S. aureus in 0.3ml suspension in a porcine model.

Lemierre's syndrome and other disseminated Fusobacterium necrophorum infections in Denmark: a prospective epidemiological and clinical survey.

In a 3-year prospective study, all cases of disseminated Fusobacterium necrophorum infections found in Denmark from 1998 to 2001 were analysed, with the aim of describing the epidemiology and clinical features of the variants of Lemierre's syndrome and disseminated non-head-and-neck-associated F. necrophorum infections. Fifty-eight cases of Lemierre's syndrome were reported in previously healthy persons, with an incidence of 14.4 cases per million per year in youngsters aged 15-24 years old. There was no increase during the study period. Lemierre's syndrome originating from an oropharyngeal infection was seen in 37 youngsters. An otogenic variant of Lemierre's syndrome was seen in 5 children with dissemination to nearby regions, and other variants of Lemierre's syndrome, e.g. from the sinuses and teeth, were seen in 16 adults. Patients often had metastatic infections already on admission and needed prolonged hospitalisation. The overall mortality of Lemierre's syndrome was 9%. Forty-two elderly patients had disseminated F. necrophorum infections originating from foci in lower parts of the body. They frequently had predisposing diseases, e.g. abdominal or urogenital cancers, which contributed to the high mortality of 26%. This study shows that the incidence of Lemierre's syndrome is higher than that previously found and has a characteristic age distribution. Early suspicion of the diagnosis, several weeks of antibiotic therapy, often combined with surgical drainage, is mandatory to lower the mortality. In disseminated non-head-and-neck-associated F. necrophorum infections, underlying cancers must be considered.

Laparoscopic diagnosis and treatment of aortic vascular prosthetic graft infections in a porcine model.

OBJECTIVES: To study the feasibility and efficacy of experimental laparoscopy in the diagnosis of aortic graft infection in pigs. MATERIAL AND METHODS: Eight pigs had an aortic tube graft implanted and inoculated with either 5 x 10(4) or 10(6) CFU of Staphylococcus aureus ATCC 29213. Laparoscopy was performed after a median of 20 days with debridement and sampling for bacterial culture. Thereafter, the grafts were locally soaked in rifampicin and postoperatively, the pigs received rifampicin and ciprofloxacin orally for two weeks and were then sacrificed. RESULTS: All pigs developed graft infection. One pig died from severe clostridial septicaemia before laparoscopy could be performed. The remaining pigs had all samples for bacterial culture taken by laparoscopy from the inflamed tissue. The temperature dropped significantly after laparoscopy, and no macroscopic signs of infection presented at autopsy. However, only culture from one pig was without S. aureus at autopsy. CONCLUSIONS: Laparoscopy is a potential diagnostic tool for aortic graft infection and also affords the opportunity to carry out bacteriological sampling and local antibiotic treatment. The efficacy of laparoscopic treatment needs further evaluation.

Diagnosis of Chlamydia trachomatis infections in a sexually transmitted disease clinic: evaluation of a urine sample tested by enzyme immunoassay and polymerase chain reaction in comparison with a cervical and/or a urethral swab tested by culture and polymerase chain reaction.

OBJECTIVE: To evaluate the value of a urine sample for diagnosing Chlamydia trachomatis infection in an STD clinic in a prospective study of samples collected from 410 consecutive STD patients (167 female and 243 male). METHODS: Urine samples were tested by enzyme immunoassay (EIA) and polymerase chain reaction (PCR) in comparison with cervical and/or urethral swabs tested by PCR and cell culture. A questionnaire was completed for a total of 320 patients concerning symptoms, and determining whether they were controls, contacts or were being tested subsequent to legal abortion. RESULTS: The overall prevalence of C. trachomatis infection was 11.5%. At least 40% of patients were asymptomatic. Of the C. trachomatis-positive patients, 85% were diagnosed by testing urine, compared to 91% by testing swabs. For urine tests, the sensitivities of PCR were 66.7% and 71.9% for female and male patients, respectively, and the sensitivities of EIA were 40.0% and 62.5%, or 46.7% and 71.9%, for female and male patients, respectively, by including a 30% gray zone below the cut-off value. For swabs, the sensitivities of PCR were 93.3% and 87.5% for female and male patients, respectively, and equal to the sensitivities of culture. In total, 3.3% of controls and 35% of contacts were found to be C. trachomatis positive. CONCLUSION: The use of urine samples for the diagnosis of C. trachomatis infections was effective, but urine samples should be additional to conventional swab(s) instead of replacing. Partner notification and a confirmation of cure is recommended.

Human necrobacillosis, with emphasis on Lemierre's syndrome.

Lemierre's syndrome is the classical presentation of human necrobacillosis. It is characterized by a primary infection in the head in a young, previously healthy person who subsequently develops persistent high fever and disseminated metastatic abscesses, frequently including a septic thrombophlebitis of the internal jugular vein. The main pathogen is Fusobacterium necrophorum, an obligate anaerobic, pleomorphic, gram-negative rod. Clinical microbiologists have a key role in alerting clinicians and advising proper antibiotic treatment when the characteristic microscopic morphology of the pleomorphic F. necrophorum is seen in Gram stains from positive anaerobic cultures of blood and pus. Early diagnosis and prolonged appropriate antibiotic treatment with good anaerobic coverage are crucial to reduce morbidity and mortality. F. necrophorum also causes human necrobacillosis with foci caudal to the head, mainly in elderly patients with high mortality related to age and predisposing diseases, such as cancers of the primary focus.

Incidence and clinical epidemiology of necrobacillosis, including Lemierre's syndrome, in Denmark 1990-1995.

To establish the incidence and describe the clinical epidemiology of necrobacillosis and Lemierre's syndrome in Denmark, the clinical records of all laboratory-recorded cases of septicaemia due to Fusobacterium necrophorum biovar A, B, and C were reviewed retrospectively during a 6-year period. The incidence of necrobacillosis and Lemierre's syndrome was 1.5 and 0.8 per million persons per year, respectively, showing a tendency to increase during the period. Fusobacterium necrophorum was grown after three days' incubation, but the characteristic pleomorphic fusiform morphology was often disregarded as an important help in diagnosing necrobacillosis. The 24 patients with Lemierre's syndrome were all young and previously healthy, and none died, but pre-hospital delay was associated with a significantly higher morbidity and risk of metastatic infections. The remaining 25 patients with necrobacillosis had a high mortality, 24%, which was correlated with age and predisposing diseases, especially cancers. These findings stress the importance of a quicker clinical and microbiological diagnosis in cases of Lemierre's syndrome, and of screening for cancer in the remaining cases of necrobacillosis.

Pneumococcal endocarditis is not just a disease of the past: an analysis of 16 cases diagnosed in Denmark 1986-1997.

To remind clinicians and clinical microbiologists of the clinical features and therapeutic aspects of pneumococcal endocarditis, patients with pneumococcal endocarditis from 1986 to 1997 were identified via an enquiry to clinical microbiologists across Denmark. For all patients records were reviewed to confirm the diagnosis of pneumococcal endocarditis, and the clinical course, therapy and outcome were analysed. 16 patients with definitive pneumococcal endocarditis were found. All pneumococcal isolates were sensitive to penicillin. 15 patients had no previously known cardiac valvular disease, 10 patients had X-ray-proven pneumonia and 5 had meningitis. The aortic valve was affected in 13 patients, of whom 12 developed aortic insufficiency and 11 cardiac failure. Of 7 patients who underwent surgery, 6 needed immediate cardiac valve replacement. The 30-day case fatality rate was 19% (95% confidence limits 4-46%). Pneumococcal endocarditis must be considered when treating patients with pneumococcaemia. The most important clue to the diagnosis is a significant murmur and development of heart failure. Evaluation by transoesophageal echocardiography is helpful in determining the diagnosis and assessing the need for surgical intervention. With appropriate antibiotic therapy, close observation and cardiac valve replacement if necessary, the prognosis is better than recorded in earlier studies.

Mycoplasma in urine and blood following catheterisation of patients undergoing vascular surgery.

OBJECTIVES: The purpose of this investigation was to determine if mycoplasmas enter the bloodstream after urinary tract catheterisation in patients undergoing vascular surgery in order to evaluate the efficiency of the routine prophylactic antibiotic treatment. DESIGN: Prospective study. MATERIALS AND METHODS: A total of 100 patients (63 men and 37 women) undergoing elective vascular surgery had urine and blood cultures performed for mycoplasmas. Blood cultures were taken preoperatively after urinary tract catheterisation and the urine was collected during catheterisation. The median age of the patients was 67 years (range 42-87). RESULTS: A total of 12 (12%), 5 men and 7 women, had a positive urine culture for mycoplasmas (One patient had Mycoplasma hominis and 11 had Ureaplasma urealyticum isolated). Their median age was 60 years (range 42-76). No blood cultures were positive for Mycoplasma. CONCLUSIONS: Mycoplasmas do not enter the blood-stream after catheterization in sufficient amounts and sufficiently often to be detected by blood-cultures in this small patient sample. The number of vascular patients harbouring mycoplasmas in the urine was low and we found no indication for changes in the prophylactic antibiotic treatment based on these findings.

Subcutaneous lesions and bacteraemia due to Stenotrophomonas maltophilia in three leukaemic patients with neutropenia.

Subcutaneous lesions were seen in three of 13 neutropenia patients who had Stenotrophomonas (Xanthomonas) maltophilia bacteraemia. The characteristic clinical presentation resembled leukaemic infiltrates, and were different from deep ulcers or subcutaneous nodules caused by Pseudomonas aeruginosa. The three patients had acute leukaemia and were treated with intensive combination chemotherapy. All had previously been treated with broad-spectrum antibiotics, and each patient recovered after proper combination antibiotic treatment given according to sensitivity testing.

High rate of nasopharyngeal carriage of potential pathogens among children in Greenland: results of a clinical survey of middle-ear disease.

Nasopharyngeal and middle-ear colonization with bacteria and viruses, including Mycoplasma pneumoniae and chlamydiae, was investigated in a survey of 54 children with acute otitis media (AOM) and 201 control children without AOM in Greenland. In total, 98% with AOM and 91% without AOM carried potentially pathogenic bacteria in the nasopharynx. Two or more potentially pathogenic species were carried by 78% with AOM and 57% without AOM. Haemophilus influenzae was found in 92% and 77%, respectively, but only Streptococcus pneumoniae was found significantly more often in the nasopharynx of children with AOM than in age-matched controls (P < .03). The two species were found in 22 of 24 ear-discharge specimens. Nine children (three with AOM) had chlamydiae in the nasopharynx, and seven of them reported rhinitis. Enteroviruses or rhinoviruses were detected in 23 nasopharyngeal specimens from 39 children with AOM, in 13 such specimens from 39 children without AOM (P = .040), and in 4 of 14 ear-discharge specimens. The potentially pathogenic load in the nasopharynx was massive, suggesting an association with the high prevalence of otitis media among children in Greenland.

[Vibrio vulnificus infections in Denmark during the summer of 1994]. / Vibrio vulnificus-infektioner i Danmark sommeren 1994.

The clinical manifestations and epidemiological data of 11 patients infected with Vibrio vulnificus found in Denmark during the unusually warm summer of 1994 are reported. All patients had been exposed to seawater prior to illness, but none had consumed seafood. Nine patients, including four with bacteraemia, developed skin manifestations of various degrees of severity. One patient died of septic shock despite surgery and treatment with relevant antibiotics. Four patients contracted the disease while fishing. High seawater temperature increases the risk of V. vulnificus infections even in temperate climates such as the Danish. Exposure to seawater, including handling of fresh seafood, during warm periods carries a risk of infection with V. vulnificus.

Vascular graft infections with Mycoplasma: an overlooked risk factor?

Vascular graft infection is one of the most serious complications in vascular surgery. It is associated with mortality rates ranging from 25% to 75% and with morbidity in the form of amputation in approximately 30% of patients. Staphylococcus aureus is the leading pathogen. With conventional laboratory techniques, the percentage of culture-negative yet grossly infected vascular grafts seems to be increasing and is not adequately explained by the prior use of antibiotics. We have recently reported the first case of aortic graft infection with Mycoplasma. We therefore suggest the hypothesis that the large number of culture-negative yet grossly infected vascular grafts may be due to Mycoplasma infection not detected with conventional laboratory technique.

Ceftriaxone/metronidazole is more effective than ampicillin/netilmicin/metronidazole in the treatment of bacterial peritonitis.

In a prospective, open, controlled clinical study, 190 consecutive patients who were thought to have bacterial peritonitis before operation, were randomised to antibiotic treatment during and after operation with either ceftriaxone 1 g plus metronidazole 1.5 g once daily (n = 94) or ampicillin 2 g plus netilmicin 150 mg twice daily plus metronidazole 1.5 g once daily (n = 96). Incisional and deep surgical wound infections, postoperative pneumonia and urinary tract infection as well as deaths caused by infection were recorded. Ceftriaxone-metronidazole was significantly more effective than ampicillin-netilmicin-metronidazole, 6/94 wound related infections (6%) compared to 18/96 (19%) (p = 0.02). In patients with peritonitis caused by a perforated colon or appendix the rates of clinical failure were 6% and 28%, respectively. We consider ceftriaxone plus metronidazole an efficient and easily administered antibiotic regimen in patients with bacterial peritonitis, and both the wide range of activity against Gram-negative aerobic rods and the long half life of ceftriaxone seem to be beneficial.

Ceftriaxone vs. ampicillin + metronidazole as prophylaxis against infections after clean-contaminated abdominal surgery.

In a prospective, controlled, double-blind study, 496 patients undergoing abdominal surgery were given antibiotic prophylaxis with a single dose of either ceftriaxone or ampicillin + metronidazole. No significant intergroup difference was found between the respective overall rates of infectious complications (3.2% and 4.9%). Analysis of the microbiologic findings showed incisional wound infections, mainly caused by gram-negative rods, to be more common in the ampicillin-metronidazole group, whereas deep wound infections were more frequent in the ceftriaxone group. It is concluded that ceftriaxone seems to be more efficient than ampicillin-metronidazole as prophylaxis against incisional wound infection, but should preferably be supplemented with an antianaerobic agent to prevent deep wound infections.

[Clostridium septicum and colonic cancer]. / Clostridium septicum og cancer coli.

During the period 1980-1987, Clostridium septicum was identified at Statens Seruminstitut, from anaerobic blood cultures in six patients. Five of the patients had cancer of the colon or rectum (c. coli) and one had cancer of the ovary. Correspondingly great incidence of solid tumours, particularly c. coli with C. septicum infection without preceding trauma or compromizing of immunity has been reported in the literature. Meticulous bacteriological identification should be undertaken on anaerobic culture as the finding of C. septicum in the blood should instigate investigation for c. coli or another form of solid tumour if no other explanation for the infection is available.

Prophylactic antibiotics in amputation of the lower extremity for ischemia. A placebo-controlled, randomized trial of cefoxitin.

Of 152 patients who were scheduled for an amputation for ischemia, seventy-seven were randomly assigned to perioperative prophylaxis with cefoxitin (Mefoxin) and seventy-five patients, to injections of a placebo. The patients were followed for twenty-one days or, in the case of wound complications, to the end of treatment. An infected wound occurred in 38.7 per cent of the patients in the placebo group and 16.9 per cent of those in the antibiotic group (p less than 0.005). Clostridial infection occurred in eight patients in the placebo group and in none in the antibiotic group (p = 0.003). Three of the patients with clostridial infection died of gas gangrene. A multivariate analysis showed that the absence of antibiotic prophylaxis increased the risk of infection by a factor of 3.3 (p = 0.004) and increased the need for reamputation by a factor of 4.5 (p = 0.003). We concluded that amputation patients should have prophylaxis with a broad-spectrum antibiotic given perioperatively.

A new familial skeletal dysplasia with severely retarded ossification and abnormal modeling of bones especially of the epiphyses, the hands, and feet.

Three brothers with a constitutional skeletal dysplasia characterized by an excessively retarded ossification, principally of the epiphyses, the pelvis, the hands and the feet, are reported. In the hands and feet the retarded ossification is combined with an abnormal modeling of the bones. All the children appeared normal at birth. At the time of examination a moderate degree of dwarfism could be predicted. There was no mental retardation. All laboratory investigations including chromosomal analyses and examination for acid mucopolysaccharides in the urine were normal. Parental consanguinity suggest an autosomal recessive inheritance. There is no resemblance of this disorder to any of the hitherto described groups of constitutional diseases of bones.