Oedema as a risk factor for multiple episodes of cellulitis

Oedema as a risk factor for multiple episodes of cellulitis/erysipelas of the lower leg: a series with community follow-up.

1: Br J Dermatol. 2006 Nov;155(5):947-50.

Cox NH.

Dermatology Department, Cumberland Infirmary, Carlisle CA2 7HY, U.K.

Background

Cellulitis of the lower leg is a common problem with considerable morbidity. Risk factors are well identified but the relationship between consequences of cellulitis and further episodes is less well understood.

Objectives

To review risk factors, treatment and complications in patients with lower leg cellulitis, to determine the frequency of long-term complications and of further episodes, and any relationship between them, and to consider the likely impact of preventive strategies based on these results.

Methods

Patients with ascending, presumed streptococcal, cellulitis of the lower leg were identified retrospectively from hospital coding. Hospital records, together with questionnaires to both general practitioners and patients, were used to record subsequent complications and identifiable risk factors for further episodes.

Results

Of 171 patients, 81 (47%) had recurrent episodes and 79 (46%) had chronic oedema. The concurrence of these two factors was strongly correlated (P <>

Conclusions

This study demonstrates that the true frequency of postcellulitic oedema, as well as that of further episodes, is probably underestimated. Furthermore, there is a strong association between these factors, each of which is both a risk factor for, and a consequence of, each other, and for which intervention (reduction of oedema or more prolonged antibiotic therapy) may reduce the risk of recurrent infection. By contrast, self-reporting of toeweb maceration is low, so attempts to reduce the risk of recurrent cellulitis by treatment of tinea pedis or bacterial intertrigo may fail.

British Journal of Dermatology

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Lower limb cellulitis: features associated with length of hospital stay.

1: J Infect. 2006 Jan;52(1):23-9.

Department of Infectious Diseases, Christchurch Hospital, Private Bag 4710, Christchurch, New Zealand.

AIMS:

This study aimed to identify features associated with length of hospital stay (LOHS), length of intravenous antibiotic therapy (LIVAT) and six-week outcomes for patients with lower limb cellulitis, and to test the Eron/Passos classification of cellulitis in the New Zealand system.

METHODS:

Eighty-five variables were collected prospectively from a cohort of 51 inpatients admitted to Christchurch hospital. The primary end-point for analysis was LOHS. LIVAT and six-week outcomes were secondary end-points.

RESULTS:

On univariate analysis use of diuretics, living alone, cellulitis acuity, a creatinine concentration of >0.1 mmol/l, poor mobility, pulse >90 bpm, age >70 years, oedema extent, chronic oedema, ulceration, neutrophil count >10x10(9)/l, erythema area >1000 cm2 and haemoglobin concentration less than normal were significantly (P= or <0.05) or ="3">7 days was associated with use of diuretics, living alone, age >70 years, more oedema, erythema area >1000 cm2, haemoglobin less than normal, ulceration, creatinine >0.1 mmol/l and poor mobility. The presence of a discharge was associated with LIVAT. Multivariate analysis accounted for 48% of the variance in LOHS and 16% for LIVAT. Use of diuretics, neutrophil count >10x10(9)/l and oedema score were independently associated with LOHS, with oedema score associated with short stay and diuretic use with long stay. The Eron/Passos system was not helpful so a new scoring system was devised which successfully classified patients into length of stay groups.

CONCLUSIONS:

The clinical features analysed accounted for half of the variance in LOHS. An important reason may be physician discretion. If so, our scoring system based on these results could be used in a clinical pathway to improve patient care. This tool would need to be evaluated prospectively.

Keywords: Lower limb cellulitis; Length of hospital stay

Journal of Infections

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Risk factors for acute cellulitis of the lower limb: a prospective case-control study.

Bjornsdottir S,
Gottfredsson M,
Thorisdottir AS,
Gunnarsson GB,
Rikardsdottir H,
Kristjansson M,
Hilmarsdottir I.

Department of Medicine, Division of Infectious Diseases, Landspitali University Hospital, Reykjavik, Iceland.

BACKGROUND:

Acute bacterial cellulitis is a potentially serious infection that commonly recurs. The identification of preventable risk factors could reduce infection-related morbidity and cost and improve patient management. The aim of this study was to identify the risk factors associated with lower-limb cellulitis, including both analysis of risk factors associated with cellulitis in either limb and risk factors in a single limb associated with cellulitis in the same limb. We placed particular emphasis on dermatophytic infections of the foot and bacterial infection and colonization of the toe webs.

METHODS:

We conducted a prospective case-control study of 100 subjects with cellulitis and 200 control subjects, matched for age and sex, who were admitted to a university hospital during the period October 2000-February 2004. Data were obtained with a questionnaire and from examination of lower limbs and microbiological analyses of samples from the feet.

RESULTS:

The median age of the participants was 66.5 years (interquartile range, 48.8-77.0). The following risk factors were strongly and independently associated with cellulitis: previous history of cellulitis (OR, 31.04; 95% CI, 4.15-232.20), the presence of Staphylococcus aureus and/or beta -hemolytic streptococci in the toe webs (OR, 28.97; 95% CI, 5.47-153.48), presence of leg erosions or ulcers (OR, 11.80; 95% CI, 2.47-56.33), and prior saphenectomy (OR, 8.49; 95% CI, 1.62-44.52). Tinea pedis interdigitalis was associated with cellulitis only when toe web bacteria were excluded from the analysis (OR, 3.86; 95% CI, 1.32-11.27).

CONCLUSIONS:

Risk factors for acute bacterial cellulitis in hospitalized patients include predisposing factors and the presence of sites of pathogen entry on legs and toe webs. These findings indicate that improved awareness and management of toe web intertrigo, which may harbor bacterial pathogens, and other skin lesions might reduce the incidence of cellulitis.

University of Chicago Press

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Chronic dermatomycoses of the foot as risk factors for acute bacterial cellulitis of the leg: a case-control study.

Roujeau JC,
Sigurgeirsson B,
Korting HC,
Kerl H,
Paul C.

Service de Dermatologie, Hopital Henri-Mondor, Creteil, France. jean-claude.roujeau@hmn.ap-hop-paris.fr

OBJECTIVE:

To assess the role of foot dermatomycosis (tinea pedis and onychomycosis) and other candidate risk factors in the development of acute bacterial cellulitis of the leg.

METHODS:

A case-control study, including 243 patients (cases) with acute bacterial cellulitis of the leg and 467 controls, 2 per case, individually matched for gender, age (+/-5 years), hospital and admission date (+/-2 months).

RESULTS:

Overall, mycology-proven foot dermatomycosis was a significant risk factor for acute bacterial cellulitis (odds ratio, OR: 2.4; p < p =" 0.005)">

CONCLUSIONS:

Tinea pedis and onychomycosis were found to be significant risk factors for acute bacterial cellulitis of the leg that are readily amenable to treatment with effective pharmacological therapy. Copyright (c) 2004 S. Karger AG, Basel.

Full Text Article

Bacteremia and Multifocal Cellulitis due to Helicobacter canis

Bacteremia and Multifocal Cellulitis due to Helicobacter canis: First Case in an Immunocompetent Patient

Corinne Leemann, Eleonora Gambillara, Guy Prod'hom, Katia Jaton, Renato Panizzon, Jacques Bille, Patrick Francioli, Gilbert Greub, Emmanuel Laffitte, and Philip E. Tarr*

Infectious Diseases Service, Dermatology Service, University Hospital of Lausanne, Switzerland; Microbiology Institute, University of Lausanne, Switzerland

* To whom correspondence should be addressed. Email: philip.tarr@chuv.ch

Abstract

Bacteremia due to Helicobacter canis has been reported in a patient with X-linked hypogammaglobulinemia. Here we report the first human case of H. canis bacteremia in an immunocompetent host. Identification of the organism was made by genetic and phylogenetic analysis of the complete 16S rRNA sequence

American Society for Microbiology

Related Article

Helicobacter sp. Flexispira Bacteremia in an Immunocompetent Young Adult

Anne Iten,1, Susanne Graf,2, Martin Egger,2,§ Martin Täuber,1,2 and Joerg Graf2,*
University Hospital Insel,1 and Institute for Infectious Diseases, University of Berne,2 CH-3010 Berne, Switzerland
Received 11 September 2000/Returned for modification 29 November 2000/Accepted 28 January 2001

Abstract

A young immunocompetent patient was admitted for a febrile illness with malaise, arthralgias, painful leg swelling, and polyserositis. Shortly prior to becoming ill, the patient had traveled to the Northern African desert. The symptoms disappeared during treatment with antibiotics (doxycycline and ceftriaxone) but recurred twice after stopping therapy. A motile gram-negative fusiform rod was isolated from a blood culture taken on the first admission. Analysis of the 16S rRNA gene of the blood culture isolate revealed close similarity with Helicobacter sp. flexispira taxon 8 (99.9% identity), a species that was previously reported as "Flexispira rappini." This is the first reported case of a recurrent Helicobacter sp. flexispira bacteremia in an adult, immunocompetent patient.

Introduction

In recent years, several new members of the genus Helicobacter have been isolated from numerous human and animal sources. Members of the genus Helicobacter include Helicobacter pylori, the organism associated with atrophic gastritis and duodenal and gastric ulcers, as well as other, less-common organisms such as H. bilis (4), H. canis (21), H. acinonyx (21), and H. trogontum (14). Previously, a group of organisms closely related to the Helicobacter spp. was called provisionally "Flexispira rappini" (3, 16, 21, 25). These bacteria are gram negative, microaerophilic, and fusiform shaped, with periplasmic fibers and bipolar tufts of sheathed flagella (3; J. H. Bryner, 4th Int. Workshop Campylobacter Infections, p. 440-442, 1987; J. H. Bryner, 14th Int. Cong. Microbiol., 1986). In a recent study, the phylogenetic relationship of the strains that comprise the group "F. rappini" was determined and 10 different taxa were identified that were grouped with various Helicobacter species (3). The study proposed that the "F. rappini" strains should be referred to as Helicobacter sp. and the appropriate flexispira taxon number, for example, Helicobacter sp. flexispira taxon 1 (3).

Strains of Helicobacter sp. flexispira have been isolated from various animal sources, including aborted sheep fetuses (8), intestinal mucosae of laboratory mice (18), and stools of puppies (2, 17). The organism also has been rarely recovered from human clinical specimens. The initial report of Helicobacter sp. flexispira isolates from humans described two men with a mild chronic diarrhea, in whom stool cultures were positive for Helicobacter sp. flexispira (17). A case of Helicobacter sp. flexispira bacteremia has been described in a child with pneumonia (22). Two cases of recurrent Helicobacter sp. flexispira bacteremia have been reported: one in an adult patient undergoing hemodialysis (20) and another one in a patient with X-linked agammaglobulinemia (27). These three isolates belonged to the Helicobacter sp. flexispira taxon 8 (3). Other Helicobacter species, such as H. cinaedi and H. fennelliae, have been occasionally recovered from the blood of adult patients, mostly patients with human immunodeficiency virus (HIV) infection who presented with cellulitis (7, 13, 19, 24). One recent investigation isolated H. cinaedi from an immunocompetent patient with septic arthritis and bacteremia (10). In the present report, we describe the first immunocompetent adult with recurrent Helicobacter sp. flexispira taxon 8 bacteremia.

Case Report

A 36-year-old female patient presented at the emergency department with a history of several days of fever and general malaise. She had abdominal pain, but no diarrhea. Except for a past history of malaria tropica 4 years earlier, she was in good health. One week before the current illness, she had returned after a 2-week period of travel in the Algerian desert, where she had observed a skin lesion on the lower limb compatible with the prick of an insect but was otherwise healthy. Laboratory investigations in the emergency department yielded a hemoglobin level of 140 g/liter, a leukocyte count of 11.4 × 109/liter (82.5% neutrophils with a left shift), and a platelet count of 190 × 109/liter. The C-reactive protein level was 15 mg/liter. Blood smears for malaria were negative, and no Plasmodium falciparum antigens were detected. A chest X-ray was normal. The patient was discharged.

The following day, the patient was admitted because of sweats, chills, fever, diffuse arthralgias, and painful legs. Physical examination showed a maximal temperature of 39.2°C and swelling of the legs. Abdominal examination showed no organomegaly. There was no lymphadenopathy. Laboratory investigations revealed a hemoglobin level of 135 g/liter, a leukocyte count of 18.7 × 109/liter (neutrophils at 88.0% with a left shift), and a platelet count of 183 × 109/liter. The C-reactive protein level was 183 mg/liter, and the creatinine kinase level was normal. A total of seven blood cultures were drawn on admission and during the next few days. All but the first blood culture remained sterile. Initial identification of the positive blood culture indicated a Campylobacter-like organism. Urine culture and microbiological examination of the stool (bacteria, parasites) were negative. Serologic tests were positive for past infections with Epstein-Barr virus and hepatitis A and were negative for HIV and H. pylori. The serology result for Campylobacter spp. was borderline positive.

The patient was treated empirically with ceftriaxone (2 g/day) and doxycycline (200 mg/day) intravenously. On day 9, a chest X-ray showed bilateral pleural effusion. The cultures of this exudate remained sterile. Echocardiography on day 10 showed pericardial effusion that was not hemodynamically relevant. An abdominal computed tomography scan was normal. The patient improved slowly with resolution of fever, pleuritis, and pericarditis. Ceftriaxone was stopped on day 16 because of a possible allergy (fever and rash), and doxycycline was stopped on day 23. The patient was discharged on day 24.

The patient was seen again in the outpatient clinic 14 days later. She was asymptomatic; her blood counts and C-reactive protein levels were normal, and a chest X-ray showed no abnormalities.

Nine days later, the patient was readmitted to the hospital because of recurrent fever and dyspnea. Laboratory tests showed a hemoglobin level of 131 g/liter, a leukocyte count of 14.9 × 109/liter (neutrophils at 85.3% with a left shift), a platelet count of 380 × 109/liter, and an increased C-reactive protein level of 136 mg/liter. Several blood cultures remained negative. A relapse of the pericardial and bilateral pleural effusions was documented. The pleural exudate cultures remained sterile for bacteria, mycobacteria, and fungi. Antinuclear antibodies and rheumatoid factors were negative, and protein electrophoresis was normal. Empirical intravenous antibiotic therapy was begun on the day of admission with levofloxacin (1,000 mg/day), to which doxycycline (200 mg/day) was added 2 days later. The patient improved rapidly with disappearance of pleural and pericardial effusion and normalization of laboratory tests. Levofloxacin was continued for a total of 9 days and doxycycline for a total of 6 weeks.

Two weeks after stopping doxycycline, the patient noted again sweats, fever, and dyspnea. Physical examination was normal. Blood tests showed an increased C-reactive protein level (142 mg/liter). Blood cultures remained negative. Echocardiography and a chest X-ray showed mild pericardial and pleural effusions. The patient was treated symptomatically without antibiotics. The patient recovered completely with no further recurrences of her symptoms during an 11-month follow-up period.

Materials and Methods

Blood cultures. Several blood samples of 10 ml each were obtained by venipuncture. Blood samples were inoculated into BacT/Alert FAN aerobe and anaerobic blood culture bottles. The vials were monitored with the BacT/Alert automatic blood culture system and routinely incubated for 5 days at 37°C. According our routine protocol for positive cultures, gram-stained smears and subcultures on chocolate and blood agar were done with the broth of vials with positive growth.

Growth conditions and microscopic examination. Gram staining and dark-field microscopy of a wet-mount preparation were performed by standard methods. Subcultures were performed on Columbia sheep blood, chocolate, and anaerobe blood agars and incubated at 37°C in 5% CO2. The same media, as well as a Preston agar plate for the cultivation of Campylobacter species, were incubated in a microaerophilic atmosphere (CampyGen; Oxoid). In addition BSK II (for the cultivation of Borrelia and Spirochaeta species) and Korthof medium (for the cultivation of Leptospira species) were inoculated with several drops of blood culture broth. These media were incubated aerobically at 37°C.

Electron microscopy. The bacteria were lifted off the agar and gently suspended in phosphate-buffered saline (PBS; 145 mM NaCl, 7.5 mM Na2HPO4, 3.2 mM NaH2PO4 [pH 7.1]). Two volumes of a 4% formaldehyde solution was added, and the sample was incubated at room temperature for 1 h. The sample was centrifuged at 5,000 × g for 10 min at 4°C and gently resuspended in PBS. The suspension was placed on a Formvar-coated grid for 2 min, and the cells adhering to the grid were stained with 1% uranyl acetate. The grids were examined with a Phillips EM300 electron microscope.

Biochemical characterization. Catalase production was tested with 3% hydrogen peroxide. Oxidase activity was tested with the Pyo-Test (Medical Wire & Equipment Co.).

Chromosomal DNA isolation. Chromosomal DNA was isolated with the QiaAmp DNA Minikit according to the manufacturer's instructions (Qiagen AG, Basel, Switzerland). Specifically, cells were recovered from the agar plates and resuspended in 180 µl of the buffer ATL. The sample was digested with proteinase K (Qiagen AG) overnight at 56°C and subsequently with RNase A (Boehringer Mannheim AG, Rotkreuz, Switzerland). The DNA was eluted from the columns twice with 200 µl of double-distilled water. The eluates were pooled and stored at 20°C until use.

PCR amplification and DNA sequence analysis of the 16S rRNA gene. PCR amplification of the 16S rRNA gene was done using the eubacterium-specific primer 27f (5'-AGAGTTTGATCMTGGCTCAG) and the universal primer 1492r (5'-TACGGYTACCTTGTTACGACTT [9]). Each reaction contained 200 ng of DNA, 200 µM concentrations of each deoxynucleoside triphosphate, 0.5 µM concentrations of each primer, 2 µM MgSO4, and 1 U of Vent DNA polymerase (NEB, Inc., Beverly, Mass.) in a final volume of 100 µl. The amplification conditions were as follows: (i) 5 min at 95°C; (ii) 30 cycles of 1 min at 95°C, 1 min at 50°C, and 1.5 min at 75°C; and (iii) 5 min at 75°C (modified from Haygood and Davidson [6]). The PCR products were sequenced using the following primers: 27f, 519r, 530f, 907r, 926f, and 1492r (9). From each colony type, two DNA preparations and four PCR amplifications were done to sequence both strands. The PCR products were sequenced at the central sequencing facility of the Department of Clinical Research of the University of Berne.

The sequences were compiled using SeqMan II (DNASTAR, Inc., Madison, Wis.). The consensus sequence was compared to the databases using BLAST 2.0 (1) and the Ribosomal Database Project II (12). The sequences of IMM 687835 and of related bacteria were aligned with MegAlign (DNASTAR). Phylogenetic trees were calculated and constructed using TreeCon (23). The distance estimation was done using three different algorithims: Jukes and Canters, Jin and Nei (with a = 0.5, 1, or 2), and Galtier and Gouy. The relationship of the strains was calculated using either neighbor-joining or cluster analysis using UPGMA. For each calculation, bootstrap analysis was done by resampling the data set 1,000 times. The secondary structure of the 16S rRNA was predicted using GeneQuest (DNASTAR).

Nucleotide sequence accession number. The nucleotide sequence of the 16S rRNA gene of IMM 687835 was deposited in GenBank under accession no. AF302762.

Results

Blood cultures. The strain was recovered from the initial aerobic blood culture taken prior to antibiotic therapy. The bottle gave a positive signal after 2 days of incubation. Gram staining of this blood culture showed a curved, gram-negative organism. The blood culture was subcultured on Columbia sheep blood and Preston agar because, initially, a Campylobacter-like organism was suspected.

Growth requirements and microscopic examination. The initial subcultures grew very slowly, only after 16 days colonies were visible. Best growth was observed on anaerobic blood agar.

Good results were also obtained in the BSK II broth where the organism could be propagated most easily. In later subcultures, growth was already visible after 2 days of incubation at 37°C in a microaerophilic atmosphere. No growth was observed on Preston agar, in the Korthof medium, or on agar media incubated in 5% CO2. Two colony morphologies on anaerobic blood agar were observed: one was convex and undulate, and the other was flat and spreading. Colonies were alpha- or slightly beta-hemolytic. A particular smell was noted that was reminiscent of chlorine.

Gram staining showed a slender, fusiform gram-negative rod. In the dark-field preparation, living bacteria showed a twisting motion. Electron microscopy revealed a thin, curved, fusiform bacterium up to 4 µm long, with bipolar sheathed flagella; interestingly, no periplasmic fibers were observed (Fig. 1).

Phenotypic characterization. The isolate was positive for oxidase and negative for the production of catalase. Further biochemical characterization could not be performed because the growth rate of the organism was too slow.

16S rRNA gene sequence analysis. The DNA sequence of the 16S rRNA gene was identical for both colony morphologies, indicating that the different colonies types were variants of the same strain. Using BLAST 2.0 (1) and the Ribosomal Database Project II (12), the 16S rRNA gene sequence of the isolate was compared to the databases. This revealed that this strain was most similar to Helicobacter sp. flexispira taxon 8. The next-closest species, according to the 16S rRNA gene sequence, was a strain of H. cinaedi, followed by H. bilis. Alignment of the 16S rRNA genes revealed the presence of a 217-bp insert after nucleotide 156. Similar intervening sequences (IVS) at the same location in the 16S rRNA gene have been described in H. bilis (4), in H. canis (11), in H. cinaedi (26), in some "F. rappini" strains (4), and in a recently described new Helicobacter species (5). The IVS from IMM 687835 was most similar to the IVS from an H. cinaedi strain, CCUG 33887 (AF207738). The next most closely related IVS were from H. bilis. The IVS were shown to be highly variable in length and in base composition (4) and may alter the phylogenetic relationship between strains (15). Thus, we excluded the IVS from the 16S rRNA gene sequence for the subsequent phylogenetic analysis.

The phylogenetic relationship of IMM 687835 with other Helicobacter species was determined using TreeCon (23). The distance estimation was calculated using three different algorithms, and the phylogenetic relationship was determined either by neighbor-joining or clustering analysis. In all cases, IMM 687835 clustered with Helicobacter sp. flexispira taxon 8 strains (Fig. 2). Two nucleotide differences of 1,399 nucleotides were detected between IMM 687835 and the Helicobacter sp. flexispira taxon 8 strains ATCC 49317 (accession no. AF047851) and H1353 (accession no. AF118017). IMM 687835 was contained in a cluster that included four Helicobacter sp. flexispira taxon 8 strains and two H. cinaedi strains that had been isolated from dog feces (boot strap value of 64%). The type strain of H. cinaedi formed a cluster with H. westmeadii (bootstrap value of 100%) that was distinct from the Helicobacter sp. flexispira taxon 8 cluster. The further taxonomic characterization of the strains contained within the Helicobacter sp. flexispira taxon 8 cluster needs to be addressed in a study that includes numerous isolates of closely related species and employs several different methodologies (3, 26). The sequence similarity and the consistent placement in the phylogenetic trees indicate that the isolate described in our study is Helicobacter sp. flexispira taxon 8.

Discussion

In this report, we provide the first description of recurrent bacteremia with Helicobacter sp. flexispira taxon 8 in a young, healthy, immunocompetent woman without obvious risk factors. The bacteremia was associated with severe malaise, high fevers, arthralgias, painful leg swelling, and pericardial and pleural effusions. This is also the first patient with a Helicobacter sp. flexispira infection in whom polyserositis (pericardial and pleural effusion) has been observed. One previously described patient with agammaglobulinemia presented with persistent septicemia and leg swelling. Interestingly, the present patient also presented initially with bilateral painful leg swelling. The two other reported patients, a man undergoing hemodialysis and an otherwise healthy child, had evidence of lung infections as the most prominent organ involvement. In our patient, pulmonary involvement was limited to pleural effusions.
Response to antibiotic therapy was slow, and the patient had two episodes of relapsing symptoms after stopping antibiotic therapy, including recurrence of the pleural and pericardial effusions. The reason for the relapsing course is not known. During both relapses the blood cultures remained negative, and the second relapse was not treated with antibiotics and subsided spontaneously. The patient has since remained well. It is conceivable that relapsing symptoms were mediated by immunological phenomena. Alternatively, low-level recurrence of the bacteremia from an unrecognized persistant focus of infection may have escaped detection by blood cultures, since the organism is difficult to isolate (2, 20).

The susceptibility of our strain was not tested because of slow growth and lack of standardized procedures for this organism. Previous studies have reported that the organism is susceptible to doxycycline, ceftriaxone, and ciprofloxacine (20, 22). Our patient was thus treated with three antibiotics, all of which appear to be active in vitro against Helicobacter sp. flexispira taxon 8 strains. In contrast, in the agammaglobulinemic patient bacteremia persisted for months despite treatment with multiple antibiotics (including doxycycline, quinolones, and beta-lactams) and only cleared after prolonged therapy with imipenem and gentamicin. This may indicate that therapy for bacteremia is more difficult in immunocompromised patients.

The identification of Helicobacter sp. flexispira taxon 8 was difficult. As already described, the culture of Helicobacter sp. flexispira is fastidious. Because of the characteristic motility of these organisms, dark-field or phase-contrast microscopy of a wet-mount preparation can provide first clues as to its nature and help select the strategy to conclusively identify the pathogen. We and others used 16S rRNA gene sequencing. Phylogenetic analysis, independent of the algorithm used, grouped our isolate with Helicobacter sp. flexispira taxon 8. Interestingly, electron microscopy of our isolate did not reveal the typical flexispira morphology. No periplasmic fibers and no tufts of polar flagella were detected. Instead IMM 687835 had single bipolar flagella. This morphology is similar to that of an unpublished Helicobacter sp. flexispira taxon 8 strain, MIT 97-5078C, that was isolated from mice (F. E. Dewhirst, personal communication). This suggests that, although Helicobacter sp. flexispira taxon 8 has very similar 16S rRNA gene sequences, its morphology as determined by electron microscopy can vary.

Helicobacter sp. flexispira is considered a natural inhabitant of the intestinal mucosa of animals (18). In the present case, the source of the infection could not be identified. It is conceivable that the patient acquired the organism while traveling in the North-African desert. While an insect bite was reported by the patient, other sources of infection could not be excluded. In other patients, animal contacts have been implicated in the acquisition of Helicobacter sp. flexispira taxon 8 strains (17).

The present report indicates that immunocompetent adults can be infected with Helicobacter sp. flexispira taxon 8 and develop a prolonged and relapsing febrile illness with involvement of multiple organs.

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