Comparison of the performance of IFA, CFA, and ELISA assays for the serodiagnosis of acute Q fever by quality assessment

The indirect immunofluorescence assay (IFA) is considered the reference method for diagnosing Q fever, but serology is also performed by complement fixation assay (CFA) or enzyme-linked immunosorbent assay (ELISA). However, comparability between these assays is not clear, and therefore a quality assessment was performed. A total of 25 serum samples from negative controls, Q fever patients, and a serial diluted high-positive sample were analyzed in 10 Dutch laboratories. Six laboratories performed CFA, 5 performed IFA, and 5 performed ELISAs. Three international reference laboratories from Australia, France, and the USA also participated in this study. Qualitative values between laboratories using the same methods were within close range, and all 3 methods correctly identified acute Q fever patients. The IFA, ELISA, and CFA are all suitable serodiagnostic assays to diagnose acute Q fever, but the IFA remains an important tool in the follow-up of patients and in identifying patients at risk for developing chronic Q fever.

The value of antibiotic prophylaxis during extracorporeal shock wave lithotripsy in the prevention of urinary tract infections in patients with urine proven sterile prior to treatment

INTRODUCTION

There are controversies in the literature regarding the need for and duration of antibiotic prophylaxis in patients treated with extracorporeal shock wave lithotripsy (ESWL) who have a negative urine culture before treatment. In order to determine the efficacy of antibiotic prophylaxis in ESWL treatment of patients with proven sterile urine, a randomized trial was performed.

METHODS

Patients were randomized for placebo and 1 or 7 days antibiotic prophylaxis (cefuroxime or ciprofloxacin), starting 30 min before ESWL. Post-ESWL studies (immediately and 2 and 6 weeks after ESWL) included patient history, urine culture and Gram stain.

RESULTS

After 2 weeks 20% of the patients and after 6 weeks 23% of the patients had bacteriuria, but there was no statistical significance between patients treated with placebo or those receiving prophylactic treatment. Only 2-3% of the patients (in the prophylaxis and placebo group) had clinical and bacteriological signs of a urinary tract infection, either 2 or 6 weeks after ESWL, possibly caused by re-infection, however, since bacteria were found in none of the urine samples collected directly after ESWL. There was no beneficial effect of antibiotic prophylaxis, in the prevention of urinary tract infections in patients with a nephrostomy catheter or dilatation at the site of treatment.

CONCLUSION

We conclude that in patients with urine proven sterile prior to ESWL there is no need for antibiotic prophylaxis.

Clinical and epidemiological investigations of Acinetobacter genomospecies 3 in a neonatal intensive care unit

A prospective study of Acinetobacter isolates from a neonatal intensive care unit was performed for 24 months. Fifty-six isolates were obtained from 21 patients, and another eight were obtained from environmental specimens. Infection due to Acinetobacter organisms was established for 16 patients, 6 with septicemia, 9 with pneumonia, and 1 with a wound infection. Further investigations were performed with 38 representative isolates. Twenty-nine isolates were identified as unnamed DNA-DNA hybridization group (genomospecies) 3, three were identified as genomospecies 2 (Acinetobacter baumannii), one was identified as genomospecies 5 (Acinetobacter junii), three were identified as genomospecies 14, and two were unclassified. Eight distinguishable protein profiles, coded I through VIII, were found by cell envelope protein electrophoresis. Profile V, a common profile, was observed for 17 isolates that had been recovered from 11 patients and 1 dust specimen. These isolates, all of which belonged to genomospecies 3, had similar antibiograms and biotypes. This study has revealed that genomospecies 3 can be associated with infection and be spread in hospitals.

A scheme for daily monitoring of oral mucositis in allogeneic BMT recipients

A system was developed for scoring oral mucositis in order to investigate its connection with fever and bacteraemia due to 'viridans' streptococci. A series of 42 allogeneic bone marrow transplant recipients given demethoxydaunorubicin and total body irradiation for conditioning therapy were monitored daily for the presence of lesions, erythema, oral oedema, pain and dysphagia, each of which was graded numerically at four levels. These values were added together to yield a daily mucositis score (DMS) with a scale of 0-15. Mucositis developed shortly after transplant and progressed within a few days to grade III (WHO grade 3-4) in the majority of patients. Bacteraemia due to 'viridans' streptococci was documented in 64% of cases and the organisms were first detected as fever developed and mucositis approached its peak. The WHO scheme defined mucositis as either absent or grade 3-4 corresponding to a DMS of 4 or 5, whereas a grading system based on the most pronounced sign or symptom resulted in three grades of severity which corresponded to a DMS of less than or equal to 4, 5-9 and greater than or equal to 10 respectively. However, only the DMS permitted monitoring of mucositis through all its stages of development. The scheme therefore offers the potential for exploring causal relationships between mucosal damage, granulocytopenia, fever and bacteraemia and can be included as an independent measure in studies of prevention and therapy of complications related to mucositis.

Amplification of Borrelia burgdorferi DNA in skin biopsies from patients with Lyme disease

To determine whether the polymerase chain reaction could contribute to a better diagnosis of Lyme disease, skin biopsy samples from patients suffering from erythema chronicum migrans or acrodermatitis chronica atrophicans were tested for the presence of Borrelia burgdorferi by a polymerase chain reaction assay, which was specific for European strains. The spirochete could not be detected microscopically in any of the 15 biopsy samples obtained from nine patients. However, B. burgdorferi could be isolated from seven of eight of these samples, which indicated the presence of spirochetes. Using a nested polymerase chain reaction, we were able to detect B. burgdorferi-specific sequences in 12 of the 15 biopsy samples. Biopsy samples from three of four patients with erythema chronicum migrans and four of five patients with acrodermatitis chronica atrophicans were found to be positive for B. burgdorferi. The spirochete could be isolated from the biopsy sample, from a patient with erythema chronicum migrans who tested negative, which suggests a false-negative polymerase chain reaction result probably on account of the low number of spirochetes present in the lesion. The positive polymerase chain reaction for lesions from patients with acrodermatis chronica atrophicans supports the concept that B. burgdorferi can persist in the skin over a long period of time. From these results, it was concluded that the polymerase chain reaction is a valuable technique for the diagnosis of Lyme disease.