diversity in vim-2-encoding class 1 integrons and occasional blashv2a carriage in isolates of a...

Acknowledgements

This study was partially presented at the 47th Interscience

Conference of Antimicrobial Agents and Chemotherapy

(ICAAC), 17–20 September 2007, Chicago, IL, USA. The

authors thank the following individuals for assistance in test-

ing and/or manuscript preparation: L. M. Deshpande, H. S.

Sader, and T. R. Fritsche.

Transparency Declaration

The authors have no conflict of interest to declare.

References

1. Walsh TR, Toleman MA, Poirel L et al. Metallo-b-lactamases: the

quiet before the storm? Clin Microbiol Rev 2005; 18: 306–325.

2. Queenan AM, Bush K. Carbapenemases: the versatile b-lactamases.

Clin Microbiol Rev 2007; 20: 440–458.

3. Koh TH, Wang GC, Sng LH. IMP-1 and a novel metallo-b-lactamase,

VIM-6, in fluorescent pseudomonads isolated in Singapore. Antimicrob

Agents Chemother 2004; 48: 2334–2336.

4. Clinical and Laboratory Standards Institute. Methods for dilution antimi-

crobial susceptibility tests for bacteria that grow aerobically; approved stan-

dard, seventh edition. M7-A7. Wayne, PA: CLSI, 2006.

5. Clinical and Laboratory Standards Institute. Performance standards for

antimicrobial susceptibility testing, 18th informational supplement. M100-

S18. Wayne, PA: CLSI, 2008.

6. Mendes RE, Kiyota KA, Monteiro J et al. Rapid detection and

identification of metallo-b-lactamase-encoding genes by multiplex

real-time PCR assay and melt curve analysis. J Clin Microbiol 2007; 45:

544–547.

7. Castanheira M, Toleman MA, Jones RN et al. Molecular characteriza-

tion of a b-lactamase gene, blaGIM-1, encoding a new subclass of

metallo-b-lactamase. Antimicrob Agents Chemother 2004; 48: 4654–4661.

8. Tenover FC, Arbeit RD, Goering RV et al. Interpreting chromosomal

DNA restriction patterns produced by pulsed-field gel electrophore-

sis: criteria for bacterial strain typing. J Clin Microbiol 1995; 33: 2233–

2239.

9. Sambrook J, MacCallum P, Russell D. Molecular cloning: a laboratory

manual, 3rd edn. Cold Spring Harbor, NY: Cold Spring Harbor Labo-

ratory Press, 2001.

Diversity in VIM-2-encoding class 1

integrons and occasional blaSHV2a carriage

in isolates of a persistent, multidrug-

resistant Pseudomonas aeruginosa clone

from Tunis

S. Hammami1, V. Gautier2, R. Ghozzi1, A. Da Costa2,

S. Ben-Redjeb1 and G. Arlet2,3

1) Laboratoire de Recherche ‘Resistance aux Antimicrobiens’, LR99ES09,

Departement de Microbiologie, Faculte de Medecine de Tunis, Tunis,

Tunisia, 2) Laboratoire de Bacteriologie, UPRES EA 2392, Faculte de Med-

ecine Pierre et Marie Curie, Universite Paris VI and 3) Service de Bacteri-

ologie-Hygiene, Hopital Tenon, Assistance Publique-Hopitaux de Paris,

Paris, France

Abstract

From 2002 to 2006, 35 of 73 multidrug-resistant Pseudomonas

aeruginosa isolates from different wards at Charles Nicolle hospi-

tal of Tunis were positive for class B carbapenemase (using the

imipenem–EDTA test), owing to a blaVIM-2 gene cassette in a

class 1 integron. Twenty-three isolates additionally produced the

extended-spectrum b-lactamase SHV2a. DNA sequences imme-

diately surrounding blaSHV2a shared extensive identity with a

Klebsiella pneumoniae plasmid sequence. Despite belonging to the

same chromosomal type, as shown by pulsed-field gel electro-

phoresis (PFGE), the VIM-2 producing P. aeruginosa isolates

prevalent at Charles Nicolle hospital displayed a diversity of

VIM-2-carrying integrons.

Keywords: Carbapenem resistance, Pseudomonas aeruginosa,

SHV-2a extended-spectrum b-lactamase, VIM-2 metallo-b-

lactamase

Original Submission: 17 March 2009; Revised

Submission: 29 July 2009; Accepted: 30 July 2009

Editor: P. Tassios

Article published online: 17 August 2009

Clin Microbiol Infect 2010; 16: 189–193

10.1111/j.1469-0691.2009.03023.x

Corresponding author and reprint requests: G. Arlet, Service

de Bacteriologie, Hopital Tenon, 4 rue de la Chine, 75970 Paris

Cedex 20, France

E-mail: [email protected]

Carbapenems are among the drugs of choice for the

treatment of infections due to multidrug-resistant (MDR)

Pseudomonas aeruginosa. However, their efficacy is being

increasingly compromised by the emergence of P. aeruginosa

strains producing metallo-b-lactamases (MBLs) [1], which are

implicated in large outbreaks, as described in Greece, Italy,

Canada, Korea and Kenya [2–6]. We report the first molec-

ular characterization of Tunisian MBL-producing P. aeruginosa

isolates, some of which were also extended-spectrum

b-lactamase producers.

CMI Research Notes 189

ª2009 The Authors

Journal Compilation ª2009 European Society of Clinical Microbiology and Infectious Diseases, CMI, 16, 179–199

A total of 73 MDR P. aeruginosa isolates (defined as being

resistant to at least three different families of antibiotics)

were collected at Charles Nicolle hospital of Tunis. Among

these isolates, 35 were positive according to the EDTA disk

synergy test (AB Biodisk, Solna, Sweden), suggesting the

presence of a class B enzyme. The frequency of MBL-produc-

ing P. aeruginosa among imipenem-resistant isolates was sta-

ble between 2002 and 2004, but increased dramatically from

2005: 1% (1/99) in 2002, 1% (1/111) in 2003, 1% (1/85) in

2004, 25% (16/65) in 2005, and 28% (16/57) in 2006. This is

consistent with the worldwide increase in the frequency of

MBL producers among P. aeruginosa clinical isolates, particu-

larly in Europe [1–4,7,8]. MICs of ticarcillin, ticarcillin–clavul-

anic acid (2 mg/L), aztreonam, ceftazidime, imipenem,

meropenem and rifampin were determined using the dilution

method on Mueller–Hinton agar, according to CLSI guide-

lines [9]. The MIC determinations showed high levels of

resistance to all b-lactams (Table 1).

In order to determine whether the MBL-producing iso-

lates were clonally related, pulsed-field gel electrophoresis

(PFGE) of SpeI-digested genomic DNA samples was per-

formed with a CHEF-DRIII apparatus (Bio-Rad Laboratories,

Hercules, CA, USA). PFGE patterns were interpreted

according to the criteria of van Belkum et al. [10]. The distri-

bution of the PFGE patterns is shown in Table 1. Only one

PFGE type was found, suggesting a clonal outbreak, including

three subtypes differing from each other by one to four

bands.

PCR amplification with primers for blaTEM, blaSHV, blaCTX-M,

blaIMP, blaVIM and blaVIM-2 (Table S1) was performed to further

investigate the presence of b-lactamase genes. Sequencing of

the amplified fragments confirmed the presence of blaVIM-2 in

all isolates. Many studies have reported that VIM-2 is the most

prevalent type of MBL in various Mediterranean countries,

i.e. Italy, Greece and France [1–3,7], but this is the first report

of the VIM-2 MBL in P. aeruginosa from Tunisia and the second

from the African continent [6].

PCR and sequencing revealed that SHV-2a was the only

class A enzyme present in our set of isolates (Table 1).

SHV-2a has been previously described in a clinical isolate of

TABLE 1. Characteristics of blaVIM-2-producing Pseudomonas aeruginosa isolates

MIC (mg/L)

Isolate

Age(years)/Sex Ward

Date(day/month/year) Specimen Imp Mem Tic Tcc Azt Caz Rif SHV-2

Gene cassettearray of class 1integrons containingan MBL gene PFGE

10 50/M ENT 09/08/2005 Pus >2048 128 >2048 >1024 64 64 256 + blaVIM-2–arr6 A212 50/M ICU 04/07/2005 Blood >2048 2048 >2048 >1024 64 512 512 + blaVIM-2–arr6 A220 45/F Surgery 24/04/2006 Catheter >2048 128 >2048 >1024 64 64 512 + blaVIM-2–arr6 A221 50/F Surgery 10/05/2006 Catheter >2048 128 2048 >1024 64 64 512 + blaVIM-2–arr6 A222 41/M Surgery 20/05/2006 Blood >2048 64 >2048 >1024 128 256 512 + blaVIM-2–arr6 A225 45/M Surgery 02/06/2006 Blood >2048 128 >2048 >1024 128 512 1024 + blaVIM-2–arr6 A226 31/M Surgery 10/06/2006 Catheter >2048 16 >2048 >1024 128 512 1024 + blaVIM-2–arr6 A227 45/M Surgery 10/06/2006 BS >2048 32 >2048 >1024 128 64 512 + blaVIM-2–arr6 A228 45/M Surgery 12/06/2006 Urine >2048 64 2048 512 128 32 512 + blaVIM-2–arr6 A229 23/M Surgery 24/06/2006 Urine >2048 1024 >2048 >1024 128 64 1024 + blaVIM-2–arr6 A230 40/F Surgery 03/07/2006 Pus >2048 128 >2048 >1024 128 64 512 + blaVIM-2–arr6 A231 65/M Surgery 03/08/2006 Catheter >2048 32 2048 1024 128 64 512 + blaVIM-2–arr6 A232 65/M Surgery 12/08/2006 Blood >2048 32 >2048 >1024 64 256 512 + blaVIM-2–arr6 A234 45/M Surgery 04/07/2006 Blood 2048 64 >2048 >1024 128 512 512 + blaVIM-2–arr6 A235 43/F Surgery 14/10/2006 BS >2048 64 >2048 >1024 256 512 1024 + blaVIM-2–arr6 A21 1/M Paediatrics 12/11/2002 Urine >2048 256 2048 >1024 64 512 <32 ) blaVIM-2–aacA7–aacA4 A12 2/M Paediatrics 03/03/2003 Urine >2048 128 2048 >1024 64 256 128 ) blaVIM-2–aacA7–aacA4 A1

11 59/M Pneumology 19/08/2005 BS >2048 128 2048 512 16 16 <32 + blaVIM-2–aacA7–aacA4 A313 59/M ICU 14/04/2005 Blood >2048 64 >2048 >1024 64 512 <32 ) blaVIM-2–aacA7–aacA4 A314 42/F ICU 23/05/2005 BS >2048 256 >2048 >1024 64 512 <32 ) blaVIM-2–aacA7–aacA4 A315 50/M ICU 07/07/2005 Catheter >2048 256 2048 >1024 64 64 <32 ) blaVIM-2–aacA7–aacA4 A317 28/M ICU 23/07/2005 Pus >2048 2048 2048 >1024 32 64 <32 ) blaVIM-2–aacA7–aacA4 A318 65/M Surgery 01/07/2005 BS >2048 2048 >2048 >1024 64 256 <32 ) blaVIM-2–aacA7–aacA4 A319 23/M ICU 01/07/2005 Blood >2048 256 >2048 >1024 64 512 <32 ) blaVIM-2–aacA7–aacA4 A323 61/M ICU 24/05/2006 Blood >2048 64 >2048 >1024 128 512 <32 ) blaVIM-2–aacA7–aacA4 A324 61/M ICU 23/05/2006 BS >2048 64 >2048 >1024 128 512 <32 ) blaVIM-2–aacA7–aacA4 A33 60/M Surgery 09/11/2004 Pus >2048 256 >2048 512 64 256 256 + blaVIM-2–aadB–arr6 A24 56/F Surgery 07/03/2005 BS >2048 128 >2048 >1024 64 256 512 + blaVIM-2–aadB–arr6 A26 69/F Surgery 24/06/2005 Blood >2048 2048 2048 512 256 64 512 + blaVIM-2–aadB–arr6 A27 52/M ICU 30/06/2005 Blood >2048 2048 >2048 >1024 64 64 256 + blaVIM-2–aadB–arr6 A2

16 55/F Surgery 30/06/2005 Blood >2048 2048 >2048 >1024 128 128 512 + blaVIM-2–aadB–arr6 A233 74/M Surgery 09/10/2006 BS >2048 64 >2048 >1024 128 512 512 + blaVIM-2–aadB–arr6 A25 39/F ICU 22/09/2005 Catheter 2048 256 >2048 >1024 64 64 <32 ) blaVIM-2–aacA7 A38 79/M ICU 04/08/2005 Catheter >2048 1024 >2048 >1024 64 512 <32 + blaVIM-2–aacA7 A39 79/M ICU 05/08/2005 Catheter 2048 128 >2048 >1024 64 512 <32 ) blaVIM-2–aacA7 A3

BS, bronchial secretions; ICU, intensive-care unit; MBL, metallo-b-lactamase; PFGE, pulsed-field gel electrophoresis; Imp, imipenem; Mem, meropenem; Tic, ticarcillin; Tcc,ticarcillin–clavulanic acid; Azt, aztreonam; Caz, ceftazidime; Rif, rifampin.

190 Clinical Microbiology and Infection, Volume 16 Number 2, February 2010 CMI

ª2009 The Authors


P. aeruginosa recovered from a French patient hospitalized in

Tunisia [11]. The coexistence of class A and class B enzymes

in the same isolate has been described in Klebsiella pneumo-

niae isolates from Tunisia [12]. Many studies have described

the association between members of these two classes of

enzymes: VIM-1 and SHV-5 [13] and VIM-4 and SHV-12 [14]

in Enterobacteriaceae, and PER-1 and VIM-2 in P. aeruginosa

[15,16].

To analyse the genetic support of these b-lactamase genes,

conjugational transfers were performed with P. aeruginosa

PAO38 rifR or Escherichia coli J53-2 rifR as the recipient

strains, with selection on aztreonam (4 mg/L), or ticarcillin

(125 mg/L), or imipenem (2 mg/L) and rifampin (250 mg/L).

Isolates 8 and 11 (with rifampin MICs <32 mg/L), which pro-

duced both VIM-2 and SHV-2a, were tested as donor strains.

Transfer experiments were unsuccessful for both genes.

DNA fragments obtained from partially Sau3A-digested

genomic DNA of two representative isolates (1 and 4) were

ligated into the vector pACYC184 digested with BamHI. E. coli

DH10B transformants were selected on Mueller–Hinton

agar supplemented with chloramphenicol (50 mg/L) and

ticarcillin (125 mg/L). The inserted DNA fragments and the

genetic organization of blaVIM-2 and blaSHV-2a were investigated

by PCR and sequencing, using the primers listed in Table S1.

First, the cloned 5599-bp fragment from isolate 1

(D1463a) was found to carry a class 1 integron. The cassette

region contained blaVIM-2, aacA7 and aacA4 (Fig. 1a). By PCR

mapping and sequencing, the same genetic organization was

found for ten additional isolates (Table 1). In the upstream

part of this integron, an insertion sequence element, ISPa7,

was bracketed by two 17-bp inverted repeats, as described

previously in In70 [3].

On the basis of PCR mapping, all other isolates also har-

boured ISPa7, intI1, and blaVIM-2. This cassette was found in

the first position of the integron, which indicates that it was

the most recently acquired resistance gene. PCR with reverse

primers specific to the 3¢-CS of class 1 integrons gave PCR

products of various sizes. In six isolates, the blaVIM-2 gene

3'CSISPa intI1

aacA7

aadB arr6

aacA4

blaVIM-2

AM774408 (a)

(b)

AM988778

FM897214

Pseudomonas aeruginosa strain R36323 (isolate 5)

Pseudomonas aeruginosa strain D1463a (isolate 1)

Pseudomonas aeruginosa strain A8243 (isolate 16)

Pseudomonas aeruginosa strain A31857 (isolate 10) FM955585

1 kb

IS26

Tn1721

IS26

blaSHV-12

blaSHV-2a

blaSHV-2a

blaSHV-2a

deor

deor

deor

deor

orf33* Salmonella typhimurium 61/9

Pseudomonas aeruginosa

Pseudomonas aeruginosa RP-1

Klebsiella pneumoniae strain KPZU-3

Plasmid p61.9

Plasmid pPA-1 (pPL20)

Plasmid pMPA2a

Strain B2781 (isolate 4)

FJ790886

AM988779

AF074954

X84714

FIG. 1. Schematic representation of the genetic environment of blaVIM-2 (a) and blaSHV-2a (b) in clinical isolates of carbapenem-resistant Pseudo-

monas aeruginosa at the Charles Nicolle Hospital in Tunis. (a) Four different genetic organizations of integrons bearing blaVIM-2, with indication of

accession number, strain and isolate. Regions with 100% identity are shown in grey. (b) Genetic context of blaSHV-2a in P. aeruginosa strain B2781

from Tunisia (isolate 4) and comparison with previously reported relevant genetic organizations (with indication of accession number, strain, and

plasmid). Regions related to the Klebsiella pneumoniae chromosome are shown in dark grey; regions with 100% identity with genetic structures

involved in blaSHV-type mobilization are shown in light grey.


ª2009 The Authors


cassette was found to be part of an integron containing two

additional cassettes: aadB and arr6, a novel rifampin ADP ri-

bosyl transferase gene (Fig. 1a). Indeed, ARR-6 shares 75–

80% amino acid identity with ARR-2, ARR-3, ARR-4 and

ARR-5. The remaining 18 isolates displayed a novel structure

for class I integrons involving two pairs of cassettes: either

blaVIM-2 and aacA7, or blaVIM-2 and arr6 (Table 1; Fig. 1a).

These combinations of gene cassettes are different from

those reported in Kenya [6]. Analysis of integron structures

yielded identical profiles in all isolates of PFGE subtype A1

and in some isolates of subtype A3, suggesting a conserved

structure of the blaVIM-2-containing integrons. However, iso-

lates of subtype A2 were shown to contain two new integ-

ron structures.

All isolates producing ARR-6 showed high levels of resis-

tance to rifampin (MIC range 256–1024 mg/L), whereas the

MIC of rifampin was <32 mg/L for all others isolates except

one (128 mg/L) (Table 1). Using the IntlI-Vim-2-for and the

3¢CS primers and the Topo XL PCR cloning kit (Invitrogen,

Cergy-Pontoise, France), the 2-kb PCR product (obtained

from isolate 10; Table 1) was cloned into electrocompetent

E. coli TOP10. After selection on kanamycin (50 mg/L) and

ticarcillin (125 mg/L), the recombinant clone harboured

blaVIM-2 (PCR-positive) and showed a high level of resistance

to rifampin (MIC >256 mg/L).

Second, the cloned 3373-bp fragment from isolate 4

(B2781) contained an IS26 insertion element, blaSHV-2a, and

Tn1721; the sequences immediately upstream and down-

stream from blaSHV-2a showed 100% DNA identity with parts

of the plasmid pMPA2a from K. pneumoniae KpZU-3 [17]

and with the plasmid pPL20 (pPa-1) from P. aeruginosa RP-1

[11] (Fig. 1b). The more distantly related sequences down-

stream from blaSHV-2a had 100% identity with Tn1721, a

transposon often found in Enterobacteriaceae [18]. On the

basis of PCR mapping, all isolates harbouring blaSHV-2a had

this same structure.

This article describes a high frequency of VIM-2 among

MDR P. aeruginosa isolates from Tunisia, as well as the

presence of new integrons encoding a VIM-2-type MBL and

the detection of a novel gene cassette containing a rifampin

resistance gene in some of these isolates. The nucleotide

sequences have been submitted to the EMBL/GenBank under

accession numbers AM774408, AM988778, AM988779,

FM897214, and FM955585.

Acknowledgements

We thank D. Decre and S. Vimont for review and critical

reading of the manuscript.

Transparency Declaration

This work was financed by grants from the Ministry of Scien-

tific Research, Technology and Competence Development of

Tunisia and from the Universite Pierre et Marie Curie, Paris

VI, Paris, France. The authors declare that they have no

conflict of interest.

Supporting Information

Additional Supporting Information may be found in the

online version of this article:

Table S1. Primers used for the identification of b-lacta-

mases and other sequences.

Please note: Wiley-Blackwell are not responsible for the

content or functionality of any supporting materials supplied

by the authors. Any queries (other than missing material)

should be directed to the corresponding author for the article.

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2. Tsakris A, Pournaras S, Woodford N et al. Outbreak of infections

caused by Pseudomonas aeruginosa producing VIM-1 carbapenemase in

Greece. J Clin Microbiol 2000; 38: 1290–1292.

3. Toleman MA, Biedenbach D, Bennett DM, Jones RN, Walsh TR. Ital-

ian metallo-beta-lactamases: a national problem? Report from the

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ther 2005; 55: 61–70.

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DL. Molecular epidemiology of metallo-beta-lactamase-producing

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5. Lee K, Lim JB, Yum JH et al. blaVIM-2 cassette-containing novel integ-

rons in metallo-b-lactamase-producing Pseudomonas aeruginosa and

Pseudomonas putida isolates disseminated in a Korean hospital. Anti-

microb Agents Chemother 2002; 46: 1053–1058.

6. Pitout JD, Revathi G, Chow BL et al. Metallo-beta-lactamase-produc-

ing Pseudomonas aeruginosa isolated from a large tertiary centre in

Kenya. Clin Microbiol Infect 2008; 14: 755–759.

7. Poirel L, Lambert T, Turkoglu S, Ronco E, Gaillard J, Nordmann P.

Characterization of class 1 integrons from Pseudomonas aeruginosa

that contain the blaVIM-2 carbapenem-hydrolyzing beta-lactamase gene

and of two novel aminoglycoside resistance gene cassettes. Antimicrob


8. Corvec S, Poirel L, Decousser JW, Allouch PY, Drugeon H, Nord-

mann P. Emergence of carbapenem-hydrolysing metallo-b-lactamase

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10. Van Belkum A, Tassios PT, Dijkshoorn L et al. Guidelines for the

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A case of benign acute childhood

myositis associated with influenza A

(H1N1) virus infection

M. Koliou1, S. Hadjiloizou2, S. Ourani1, A. Demosthenous1,

A. Hadjidemetriou1

1) Paediatric Department, Archbishop Makarios Hospital, Nicosia, Cyprus,

2) The Cyprus Paediatric Neurology Institute (CPNI) and the Cyprus

Institute of Neurology and Genetics (CING), Nicosia, Cyprus

Abstract

Benign acute childhood myositis (BACM) is a rare transient con-

dition usually occurring at the early convalescent phase of a viral

upper respiratory tract illness, normally influenza A, and, more

frequently, influenza B infection. It is characterized by acute-

onset difficulty in walking as a result of severe bilateral calf pain

and by elevated muscle enzymes including creatinine kinase. It is

self-limiting because there is rapid full recovery usually within

1 week. We describe the first case of BACM in association with

the new pandemic influenza A (H1N1) virus infection in an 11-

year-old boy from Cyprus. The child had the typical clinical and

laboratory characteristics of this clinical syndrome. Prompt diag-

nosis of this clinical entity is essential to prevent unnecessary

investigations and therapeutic interventions and to reassure the

patient and parents of the excellent prognosis.

Original Submission: 2 October 2009; Accepted: 2 October

2009

Editor: D. Raoult

Article published online: 14 October 2009

Clin Microbiol Infect 2010; 16: 193–195

10.1111/j.1469-0691.2009.03064.x

Corresponding author and reprint requests: M. Koliou,

Paediatric Department, Archbishop Makarios Hospital, Nicosia, Cyprus

E-mail: [email protected]

Benign acute childhood myositis (BACM) is a rare, self-

limiting muscle disorder mainly affecting boys of school age.

Clinically, it is characterized by the sudden onset of calf pain

and muscle tenderness, and a refusal to walk and/or difficulty

in walking. Serum creatinine kinase (CK) is elevated in most

cases. The clinical manifestations usually follow the initial

phase of an acute upper respiratory tract illness, most

frequently associated with influenza viruses, particularly

influenza B. Therefore, most of the cases reported in the

literature have been encountered during epidemics of

influenza [1–4]. Typically, the illness lasts for brief periods of

time, usually up to 1 week, and adults are very rarely

affected [5].

During the current pandemic of influenza A (H1N1) virus

infection, various complications have been described in chil-

dren and adults, including bacterial superinfections and neu-

rological complications [6–9]. In one report of hospitalized

cases with serious pneumonia and respiratory failure from

Mexico, increased CK serum levels were detected in 62% of

patients [10]. However, there have been no reported cases

with the clinical syndrome of benign acute myositis associ-

ated with the new influenza A virus in children.

We present a case of BACM associated with the new

influenza A (H1N1) virus infection in an 11-year-old boy

from Cyprus. To the best of our knowledge, this is the first

case of this clinical syndrome being reported in association

with the current influenza A pandemic.

On 5 September 2009, a previously healthy 11-year-old

boy was admitted to the Special Ward for influenza A infec-

tion of the Paediatric Department of the Archbishop Makari-

os Hospital, the main referral hospital in Nicosia, the capital


ª2009 The Authors


diversity in vim-2-encoding class 1 integrons and occasional blashv2a carriage in isolates of a...

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