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An unusual case of anti-Borrelia burgdorferi immunoglobulin G seroconversion caused by administration of intravenous gammaglobulins V. Luyasu1, S. Mullier1, O. Bauraind2 and M. Dupuis3 1 Service de Biopathologie et laboratoire de re´fe´rence Borreliose de Lyme, 2Service de Pe´diatrie and 3Service de Neurologie, Clinique Saint-Pierre, Groupe de Recherche et d’Information sur la maladie de Lyme (RILY), Avenue Reine Fabiola 9, Ottignies 1340, Belgium
Tel: þ032/10 437160
Fax: þ032/10 437188 E-mail:
[email protected]
Administration of gammaglobulins to individuals without specific anti-Borrelia burgdorferi antibodies may lead to immunoglobulin G (IgG) conversion as detected by enzyme-linked immunosorbent assay (ELISA). In some cases however, complementary techniques such as Western blot or avidity will be of prime importance in distinguishing the start of an infection from the passive immunization induced by the gammaglobulins. In all cases, the key element before reaching conclusions in relation to any of these investigations remains the confrontation between the clinical context and the biological findings. This is the scenario that has been followed in our observation. Clin Microbiol Infect 2001; 7: 697–699
CL INIC AL CON T E X T A 5-year-old child was admitted to the hospital presumptive with a diagnosis of meningitis. Over the previous 10 days, he had been suffering from pain in the legs, and during the last 48 h he had been vomiting, had experienced slight photophobia, had shown difficulty in walking, and had been in pain but not febrile. The parents reported no diarrhea and no gastroenteritis. Clinical examination revealed painful mobility of the neck. Seventy-two hours after admission, the child lost the osteotendinous reflex and developed speech difficulty. Lyme neuroborreliosis was suspected even though there was neither history of a tick bite nor erythema migrans over the previous months. The overall investigations for blood tests did not present anything particular. Prior to lumbar puncture, the brain and full spine magnetic resonance imaging with gadolinium was normal. The cerebrospinal fluid (CSF) results were as follows: leukocytes, 5/mm3; erythrocytes, 1/mm3; bacterial culture, sterile. Testing for anti-Borrelia burgdorferi IgG and IgM antibodies in the CSF was negative with both ELISA and Western blot. However, ELISA for IgM antibody was positive in the first serum sample (Table 1). A search for B. burgdorferi DNA in the CSF using the polymerase chain reaction (PCR) was negative. The CSF had an increased total protein of 227 mg/dL (normal value 0–45 mg/dL) and an increase in quantitative IgG and IgM proteins at 27 mg/dL (normal value 0–4 mg/dL), and 4.80 mg/ dL (normal value 0–0.80 mg/dL), respectively. The glucose was slightly increased to 70 mg/dL (normal value 45–65 mg/dL)
and the lactic acid was normal at 2.1 mmol/L (normal value 1.1–2.4 mmol/L). To identify the potential cross-reactions, which may cause false-positive IgM with ELISA, we undertook in-depth study for syphilis and brucellosis and for infection with Epstein–Barr virus and Chlamydia. All these investigations were negative. Agarose electrophoresis of CSF performed simultaneously with the serum sample did not reveal any oligoclonal IgG pattern suggestive of intrathecal synthesis of IgG antibody. Electromyography (EMG) showed that the nerve conduction velocities in the legs were clearly slowed down (32–37 m/s; normal value >45 m/s) while the latencies of both external popliteal sciatic nerves were strongly increased (8.9 and 10.5 ms; normal value 32 mg/L) and one strain had both mefE and ermB (MIC >32 mg/L). Thirteen strains were penicillin susceptible (MICs 0.06 mg/L), six strains were penicillin intermediate (MICs 0.125–1.0 mg/L) and seven were penicillin
Spar
resistant (MICs 2.0–4.0 mg/L). Telithromycin MICs ranged from 0.002–2.0 mg/L, with an MIC50 of 0.016 mg/L and an MIC90 of 0.25 mg/L. Enzymatic mechanisms of quinolone resistance are presented in Table 1. As can be seen, increased quinolone MICs were associated with mutations in the quinolone-resistance-determining region (QRDR) of ParC, GyrA, ParE and/or GyrB. Twenty-five strains had mutations in ParC at S79-F or Y, D83N or G, R95-C, or K137-N, with 10 having double mutations in ParC. Twenty-one strains had mutations in GyrA at S81-A, C, F, or Y; E85-K; or S114-G, with one having a double mutation in GyrA. Nineteen strains had single mutations in ParE at D435-N or I460-V. Only one strain had a mutation in
ß 2001 Copyright by the European Society of Clinical Microbiology and Infectious Diseases, CMI, 7, 697–711
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GyrB at E474-K. Nineteen strains had a total of three or four mutations in the QRDRs of ParC, GyrA, ParE and GyrB (Table 1). In the presence of reserpine 12 strains had lower ciprofloxacin MICs (4–16-fold); two strains had lower levofloxacin MICs (four-fold); one had lower moxifloxacin MICs (four-fold). Three strains had lower MICs to two agents and one strain to three agents in the presence of reserpine. Against 26 strains with significantly raised quinolone MICs and with known quinolone-resistance mechanisms, sometimes comprising more than four mutations, telithromycin yielded low MICs for all except one strain (2.0 mg/L). The latter strain carried an ermB gene. With the introduction and widespread use of broad-spectrum quinolones, such as gatifloxacin, moxifloxacin and gemifloxacin, there is a likelihood that quinolone resistance will become more widespread in pneumococci. Although many quinoloneresistant strains were penicillin susceptible, multiple resistance to penicillin G, clarithromycin and quinolones was sometimes seen in our study; this phenomenon has also been reported by other workers [10–12]. The results of this study indicate that telithromycin was still active in vitro against the great majority of these strains, and may reflect a therapeutic alternative if these strains become more prevalent.
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ACK NOW L EDGME N T This study was supported by a grant from Hoechst Marion Roussel Aventis Anti-infectives, Romainville, France.
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R EFER E NCE S 1. Appelbaum PC. Antimicrobial resistance in Streptococcus pneumoniae – an overview. Clin Infect Dis 1992; 15: 77–83. 2. Friedland IR, McCracken GH, Jr. Management of infections caused by antibiotic-resistant Streptococcus pneumoniae. N Engl J Med 1994; 331: 377–82. 3. Jacobs MR. Treatment and diagnosis of infections caused by drugresistant Streptococcus pneumoniae. Clin Infect Dis 1992; 15: 119–27. 4. Jacobs MR, Appelbaum PC. Antibiotic-resistant pneumococci. Rev Med Microbiol 1995; 6: 77–93. 5. Jacobs MR, Bajaksouzian S, Zilles A, Lin G, Pankuch GA, Appelbaum PC. Susceptibilities of Streptococcus pneumoniae and
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Haemophilus influenzae to 10 oral antimicrobial agents based on pharmacodynamic parameters. US surveillance study. Antimicrob Agents Chemother 1999; 43: 1901–8. McDougal LK, Facklam R, Reeves M et al. Analysis of multiple antimicrobial-resistant isolates of Streptococcus peumoniae from the United States. Antimicrob Agents Chemother 1992; 36: 2176–84. Munoz R, Musser JM, Crain M et al. Geographic distribution of penicillin-resistant clones of Streptococcus pneumoniae: characterization by penicillin-binding protein profile, surface protein A typing, and multilocus enzyme analysis. Clin Infect Dis 1992; 15: 112–18. Davies TA, Kelly LM, Pankuch GA, Credito KL, Jacobs MR, Appelbaum PC. Antipneumococcal activities of gemifloxacin compared to those of nine other agents. Antimicrob Agents Chemother 2000; 44: 304–10. Davies TA, Pankuch GA, Dewasse BE, Jacobs MR, Appelbaum PC. In vitro development of resistance to five quinolones and amoxicillin/clavulanate in Streptococcus pneumoniae. Antimicrob Agents Chemother 1999; 43: 1177–82. Ho P-L, Que T-L, Chang DN-C, Ng T-K, Chow K-C, Seto W-H. Emergence of fluoroquinolone resistance among multiply resistant strains of Streptococcus pneumoniae in Hong Kong. Antimicrob Agents Chemother 1999; 43: 1310–13. Chen DK, McGeer A, de Azavedo JC, Low DE. Decreased susceptibility of Streptococcus pneumoniae to fluoroquinolones in Canada. N Engl J Med 1999; 341: 233–9. Lin˜ ares J, de la Campa AG, Pallares R. Fluoroquinolone resistance in Streptococcus pneumoniae. N Engl J Med 1999; 341: 1546–7. Pankuch GA, Visalli MA, Jacobs MR, Appelbaum PC. Susceptibilities of penicillin- and erythromycin-susceptible and -resistant pneumococci to HMR 3647 (RU 66647), a new ketolide, compared with susceptibilities to 17 other agents. Antimicrob Agents Chemother 1998; 42: 624–30. National Committee for Clinical Laboratory Standards. Methods for Dilution Antimicrobial Susceptibility Tests for Bacteria that Grow Aerobically, 3rd edn. Approved Standard NCCLS Publication No M7-A4; Villanova, PA: National Committee for Clinical Laboratory Standards, 1997. Pankuch GA, Juneman SA, Davies TA, Jacobs MR, Appelbaum PC. In vitro selection of resistance to four b-lactams and azithromycin in Streptococcus pneumoniae. Antimicrob Agents Chemother 1998; 42: 2914–18. Pan XS, Ambler J, Mehtar S, Fisher LM. Involvement of topoisomerase IV and DNA gyrase as ciprofloxacin targets in Streptococcus pneumoniae. Antimicrob Agents Chemother 1996; 40: 2321–6. Brenwald NP, Gill MJ, Wise R. Prevalence of a putative efflux mechanism among fluoroquinolone-resistant clinical isolates of Streptococcus pneumoniae. Antimicrob Agents Chemother 1998; 42: 2032–5.
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706 Clinical Microbiology and Infection, Volume 7 Number 12, December 2001
Pseudomonas aeruginosa: antibiotic susceptibility and genotypic characterization of strains isolated in the intensive care unit X. Bertrand1, M. Thouverez1, C. Patry2, P. Balvay3 and D. Talon1 1
Service d’Hygie`ne Hospitalie`re et d’Epide´ miologie Mole´ culaire, 2Service de Re´ animation Chirurgicale and 3Service de Re´ animation Me´ dicale, Centre Hospitalier Universitaire Jean Minjoz, 25030 Besanc¸on, France
Tel: þ33 3 81 66 82 86
Fax: þ33 3 81 66 89 14
E-mail:
[email protected]
A prospective study was carried out to assess the incidence and the local antibiotic susceptibility of Pseudomonas aeruginosa in intensive care units (ICUs) and to characterize cross-transmission by using pulsed-field gel electrophoresis as an epidemiologic tool. For this purpose, we screened surveillance cultures and routine clinical cultures from patients admitted to two adult ICUs during a 2-year period. Antibiotic susceptibility was determined by a disk diffusion method. The overall incidence of P. aeruginosa was 19.1 cases per 100 patients. Our findings concerning the antibiotic resistance of clinical isolates were concordant with those of other studies. Genotyping revealed that approximately 53.5% of P. aeruginosa colonization was acquired via cross-transmission; the other cases probably originated from endogenous sources. Cross-colonization seems to make a large contribution to the spread of P. aeruginosa in ICUs. Accepted 31 July 2001
Clin Microbiol Infect 2001; 7: 706–708
Pseudomonas aeruginosa, a common hospital-acquired pathogen, is very important because of the number of infections caused and their gravity [1,2]. Intensive care units (ICUs) are settings of high endemicity for this pathogen, which commonly causes bronchopulmonary infections, and less frequently urinary tract infections, infections of surgical wounds, and bacteremia [3–6]. Nowadays, endemic nosocomial infections are thought to originate mainly from patients’ endogenous flora [7,8]. We carried out a prospective study to assess the incidence and the local antibiotic susceptibility of P. aeruginosa in ICUs and to characterize cross-transmission by using pulsed-field gel electrophoresis (PFGE) as an epidemiologic tool. We studied two separate adult units: the medical and surgical ICUs at the University Hospital, Besanc¸on. Each unit has 15 beds. These two units admit a total of 800 patients per year, giving a mean of 9500 patient-days per year. All patients admitted to these two ICUs between 1 January 1998 and 31 December 1999 were included in a prospective study and were tested for P. aeruginosa. Routine clinical specimens and surveillance specimens (rectal swabs, nasal swabs and tracheal aspiration) were screened for P. aeruginosa. Surveillance samples were collected from each patient on the day of admission and then once a week for the duration of hospitalization in the ICU. The disk diffusion method was used to determine the antibiotic susceptibility of the isolates, which were classified as susceptible, intermediate or resistant according to the criteria of
the Antibiogram Committee of the French Society for Microbiology [9]. P. aeruginosa colonization (identified by clinical or surveillance culture) was considered to be ICU acquired if P. aeruginosa was not detected in any specimen during the first 48 h following admission to the ICU. Endogenous colonization was defined as colonization occurring with a strain of P. aeruginosa that had not previously been isolated from another patient. Exogenous colonization or cross-colonization was defined as colonization by a strain of P. aeruginosa with a PFGE pattern identical or very similar to that of isolates from another patient present in one of the ICUs. The genetic similarity of strains was investigated by PFGE (CHEF DRIII, Bio-Rad, Ivry sur Seine, France) using DraI (Boehringer, Mannheim, Germany) as previously described [10]. Samples of SmaI-restricted DNA of Staphylococcus aureus NCTC 8325 were included in each run as an internal reference. The banding patterns were analyzed by scanning photographic negatives. GelCompar software (version 4.1) was used for cluster analysis (Applied Maths, Kortrijk, Belgium). Each strain was first compared with all other strains, and the Dice correlation coefficient was used to calculate similarity. The strains were then grouped and the UPGMA clustering algorithm was used to depict the groups as a dendrogram. Major restriction patterns were defined as those differing by more than three fragments, with a similarity index
