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A Case of Lower Respiratory Tract Infection Caused by Neisseria weaveri and Review of the Literature
96
Case Reports
doi:10.1053/jinf.2001.0965, available online at http://www.idealibrary.com on
A Case of Lower Respiratory Tract Infection Caused by Neisseria weaveri and Review of the Literature S. Panagea*, R. Bijoux, J. E. Corkill, F. Al Rashidi and C. A. Hart Department of Medical Microbiology, University of Liverpool, Daulby Street, Liverpool L69 3GA, UK Neisseria weaveri (formerly CDC [Centers for Disease Control and Prevention] group M-5 is part of the normal canine oral flora. Infections in humans are usually associated with dog bite wounds. Very rarely the organism has been isolated from sites other than wounds, or from deep seated infections. A 60-year-old man was admitted to our hospital because of an acute exacerbation of his bronchiectasis. Gram stain of bronchial washings and expectorated sputum showed numerous polymorphs and Gram-negative bacilli. Routine bacterial culture yielded a heavy pure growth of a Gram-negative rod-shaped organism that was strongly oxidase and catalase positive, indole negative, non-motile and did not ferment carbohydrates. The organism was identified as N. weaveri by using 16S rRNA sequencing. The patient was treated with a 3 weeks course of ofloxacin and had a good response. Sputum culture after treatment yielded normal respiratory flora only. To our knowledge, this is the first reported case of lower respiratory tract infection # 2002 The British Infection Society caused by N. weaveri.
Neisseria weaveri (formerly CDC [Centers for Disease Control and Prevention] group M-5) is part of the normal canine oral flora. In humans, it has been isolated predominantly from dog bite wounds. Review of the literature revealed rare reports of isolation of N. weaveri from sites other than wounds or from deepseated infections. We report a case of a lower respiratory tract infection due to N. weaveri in a patient with bronchiectasis. The organism was isolated from the patient's bronchial washings during an acute exacerbation, and its identification was confirmed by using 16S rRNA sequencing.
Introduction Neisseria weaveri (previously named CDC [Centers for Disease Control and Prevention] group M-5) [1,2] is an aerobic Gramnegative rod that is a normal inhabitant of the oropharynx of dogs. Infections in humans are usually associated with dog bite wounds. Very rarely the organism has been isolated from sites other than wounds, or from deep seated infections. We describe a patient whose sputum and bronchial washings yielded a heavy pure growth of N. weaveri during an acute exacerbation of his bronchiectasis and present a review of the literature.
*Please address all correspondence to: S. Panagea, Department of Microbiology, Royal Liverpool University Hospital, Duncan Building, Daulby Street, Liverpool L69 3GA, UK. E-mail address: [email protected] (S. Panagea). Accepted for publication 10 January 2002.
Case Report A 60-year-old man was admitted on 12 December 2000 under the Department of Respiratory Medicine because of an acute exacerbation of bronchiectasis and deterioration of respiratory function. The patient had a 15-year history of bronchiectasis, producing at least a cupful of sputum every day. He suffered from restrictive exercise tolerance and required frequently administered antibiotics and oral steroids. In the two months preceding admission his condition had deteriorated. He suffered from fatigue, reduced exercise tolerance, weight loss and increased production of sputum, which on occasion was bloodstained. He had received three courses of antibiotics. His admission temperature was 37.5 C, blood pressure 150/100 mmHg, pulse rate 92 bpm regular, and respiratory rate 24 minÿ1 with prolonged expiration. Chest examination revealed coarse expiratory sounds throughout the lungs but nothing focal. The WBC was 13.5109 lÿ1 with 10.8109 lÿ1 neutrophils. Chest X-ray showed over-inflated lungs with extensive cystic bronchiectatic changes bilaterally and a shadowing in the right lower lobe. This raised the possibility of malignancy and the patient underwent a bronchoscopy, but no endobronchial lesions were seen. Cytological examination of the bronchial washings showed numerous polymorphs but no malignant cells. Contrast enhanced CT scan of the chest showed widespread bilateral bronchiectasis and no evidence of neoplasia. Gram stain of the bronchial washings and expectorated sputum showed numerous polymorphs, no epithelial cells and numerous Gram-negative bacilli. Auramine phenol stain and culture for mycobacteria were negative. Routine bacterial culture yielded a heavy pure growth of N. weaveri.
Case Reports The deterioration of the patient's condition, which necessitated his admission, was attributed to acute infective exacerbation of his bronchiectasis. Co-amoxiclav was commenced but was stopped due to side effects (nausea). He was then treated with a 3 weeks course of ofloxacin and had a good response. The sputum cleared and decreased in volume and his general condition improved. Sputum culture after treatment yielded normal respiratory flora only.
Isolation and Identification of N. weaveri Routine bacterial culture of patient's sputum and bronchial washings yielded a heavy pure growth of a Gram-negative rodshaped organism. Colonies on blood agar were 1±2 mm in diameter, entire, flat and non-pigmented at 24 h incubation. Growth on MacConkey agar was very poor, but the organism grew well on nutrient agar. The isolate was strongly oxidase and catalase positive, indole negative, non-motile and did not ferment carbohydrates. Identification based on phenotypic characteristics proved difficult, and the API NH and API20NE gave unacceptable profiles. Electron microscopy showed a rodshaped bacterium with no flagella. Nucleotide sequencing of the 16S rRNA gene was performed using the two universal primers (5 0 to 3 0 ) UN12 (GAC TCC TAC GGG AGG CAG CAG) and UN15 (CTG ATC CGC GAT TAC TAG CGA TTC) [3]. Partial sequencing (c. 1000 bp) of the 16S rRNA gene of the organism showed 97% homology with N. weaveri (GenBank AF395911) and 97% homology with Neisseria canis (GenBank L06170). However, identification of the organism as N. canis was discounted on morphologic criteria (N. canis is a coccus while our organism was a rod). The nucleotide sequence data reported here appear in the DDBJ/EMBL/GenBank database under accession number AF429995. The isolate was also examined for the presence of the following genes of the pathogenic Neisseria spp.: pil class I (using the primers 5 0 -ACC CTT ATC GAG CTG ATG AT-3 0 and 3 0 -TGA CGG CAG GTG CTT GGT G5 0 ), pil class II (using the primers 5 0 -TGC CCG CAT ACC AAG ACT AC-3 0 and 3 0 -CGG CAG GTA GAT GGC AAG AAT T-5 0 ), porA (primers 5 0 -TCC TTG GGA CAG CAA TAA T-3 0 and 3 0 TAG CTG ATG CGT GGA ACT-5 0 ) and IgA protease (primers 5 0 -CCG ATG ATT GAT TTT AGC GT-3 0 and 3 0 -CCA TTG GCA TCC CAA ACG AC-5 0 ) [F Al Rashidi, unpublished work], but the results were negative. Antibiotic susceptibility testing using the BSAC method showed the organism to be sensitive to penicillin, ciprofloxacin, erythromycin and gentamicin, but resistant to trimethoprim. The MIC of penicillin was 0.25 mg/l by E-test, and the chromogenic cephalosporin test for detection of -lactamase production was negative.
Discussion and Review of the Literature Neisseria weaveri is the name given in 1993 to CDC group M5 strains when on the basis of DNA hybridisation, 16S rRNA sequencing and biochemical characteristics it was elevated to the species level as a new species of the genus Neisseria [1,2]. 16S rRNA sequence analysis demonstrated that it belongs to the b-3 subgroup of proteobacteria, within the Neisseriaceae cluster [2]. It is an aerobic Gram-negative straight rod of
97
varying length, non-motile, strongly oxidase and catalase positive, and does not utilise carbohydrates. It grows well between 25 and 35 C and most strains grow at 42 C. Growth on MacConkey agar is slight and variable [1,2]. The organism is difficult to identify by conventional laboratory tests [4,5]. Neisseria weaveri is part of the normal canine oral flora. Isolation rates from the oral cavities of dogs range between 12% and 18% [1]. In humans, it has been isolated predominantly from infected dog bite wounds [1,2]. In a review of Moraxella-like organisms submitted for identification to CDC in the period from 1953 to 1980, 66 of the 74 group M-5 strains were from wounds, 53 from dog bites and none from a deep site of infection [6]. Despite its common occurrence in the oral cavities of dogs it is rather infrequently isolated from infected dog bite wounds. The prevalence of N. weaveri in infected animal bite wounds in humans has been reported as 4% in the US and 6% in France [4]. It has only rarely been recovered from human sites other than wounds. Of the 45 CDC group M-5 strains examined by Holmes et al. [1] one strain was isolated from the sputum of a diabetic patient but no other clinical information was given. In another study of 41 CDC group M-5 organisms [2], 68% were from dog bite wounds, one was an eye isolate and the only isolate from a deep-seated infection was from the peritoneal and chest fluid from a woman who had recently undergone pulmonary lobectomy. A case of septicaemia due to N. weaveri has been reported in an immunosuppressed patient with multiple myelomatosis [7]. In our patient, N. weaveri was isolated as a heavy pure growth from sputum and bronchial washings during an acute exacerbation of his bronchiectasis and it is likely that infection with this organism caused the deterioration in his chronic condition. The patient's health improved after antibiotic treatment and resultant eradication of the organism from his respiratory secretions. We do not know how the patient acquired the organism and whether he had any contact with dogs. To our knowledge, this is the first reported case of lower respiratory tract infection caused by N. weaveri.
Acknowledgements We thank Dr. P. Deegan, Consultant Physician in Respiratory Medicine at Royal Liverpool Hospital for allowing us to report on his patient.
References 1 Holmes B, Costas M, On SL, Vandamme P, Falsen E, Kersters K. Neisseria weaveri sp. nov. (formerly CDC Group M-5), from dog bite wounds of humans. Int J Syst Bacteriol 1993; 43: 687±693. 2 Andersen BM, Steigerwalt AG, O'Connor SP et al. Neisseria weaveri sp. nov., formerly CDC group M-5, a gram-negative bacterium associated with dog bite wounds. J Clin Microbiol 1993; 31: 2456±2466. 3 Mahenthiralingam E, Bischof J, Byrke SK et al. DNA-Based diagnostic approaches for identification of Burkholderia cepacia Complex, Burkholderia vietnamiensis, Burkholderia multivorans, Burkholderia stabilis, and Burkholderia cepacia genomovars I and III. J Clin Microbiol 2000; 38: 3165±3173. 4 Barnham M, Holmes B. Isolation of CDC group M-5 and Staphylococcus intermedius from infected dog bites. J Infect 1992; 25: 332±334.
98
Case Reports
5 Moss CW, Wallace PL, Hollis DG, Weaver RE. Cultural and chemical characterization of CDC groups EO-2, M-5, and M-6, Moraxella (Moraxella) species, Oligella urethralis, Acinetobacter species and Psychrobacter immobilis. J Clin Microbiol 1988; 26: 484±492. 6 Graham DR, Band JD, Thornsberry C, Hollis DG, Weaver RE. Infections caused by Moraxella, Moraxella urethralis, Moraxella-like groups
M-5 and M-6, and Kingella kingae in the United States, 1953±1980. Rev Infect Dis 1990; 12: 423±431. 7 Carlson P, Kontiainen S, Anttila P, Eerola E. Septicemia caused by Neisseria weaveri. Clin Infect Dis 1997; 24: 739.
Case Reports
doi:10.1053/jinf.2001.0965, available online at http://www.idealibrary.com on
A Case of Lower Respiratory Tract Infection Caused by Neisseria weaveri and Review of the Literature S. Panagea*, R. Bijoux, J. E. Corkill, F. Al Rashidi and C. A. Hart Department of Medical Microbiology, University of Liverpool, Daulby Street, Liverpool L69 3GA, UK Neisseria weaveri (formerly CDC [Centers for Disease Control and Prevention] group M-5 is part of the normal canine oral flora. Infections in humans are usually associated with dog bite wounds. Very rarely the organism has been isolated from sites other than wounds, or from deep seated infections. A 60-year-old man was admitted to our hospital because of an acute exacerbation of his bronchiectasis. Gram stain of bronchial washings and expectorated sputum showed numerous polymorphs and Gram-negative bacilli. Routine bacterial culture yielded a heavy pure growth of a Gram-negative rod-shaped organism that was strongly oxidase and catalase positive, indole negative, non-motile and did not ferment carbohydrates. The organism was identified as N. weaveri by using 16S rRNA sequencing. The patient was treated with a 3 weeks course of ofloxacin and had a good response. Sputum culture after treatment yielded normal respiratory flora only. To our knowledge, this is the first reported case of lower respiratory tract infection # 2002 The British Infection Society caused by N. weaveri.
Neisseria weaveri (formerly CDC [Centers for Disease Control and Prevention] group M-5) is part of the normal canine oral flora. In humans, it has been isolated predominantly from dog bite wounds. Review of the literature revealed rare reports of isolation of N. weaveri from sites other than wounds or from deepseated infections. We report a case of a lower respiratory tract infection due to N. weaveri in a patient with bronchiectasis. The organism was isolated from the patient's bronchial washings during an acute exacerbation, and its identification was confirmed by using 16S rRNA sequencing.
Introduction Neisseria weaveri (previously named CDC [Centers for Disease Control and Prevention] group M-5) [1,2] is an aerobic Gramnegative rod that is a normal inhabitant of the oropharynx of dogs. Infections in humans are usually associated with dog bite wounds. Very rarely the organism has been isolated from sites other than wounds, or from deep seated infections. We describe a patient whose sputum and bronchial washings yielded a heavy pure growth of N. weaveri during an acute exacerbation of his bronchiectasis and present a review of the literature.
*Please address all correspondence to: S. Panagea, Department of Microbiology, Royal Liverpool University Hospital, Duncan Building, Daulby Street, Liverpool L69 3GA, UK. E-mail address: [email protected] (S. Panagea). Accepted for publication 10 January 2002.
Case Report A 60-year-old man was admitted on 12 December 2000 under the Department of Respiratory Medicine because of an acute exacerbation of bronchiectasis and deterioration of respiratory function. The patient had a 15-year history of bronchiectasis, producing at least a cupful of sputum every day. He suffered from restrictive exercise tolerance and required frequently administered antibiotics and oral steroids. In the two months preceding admission his condition had deteriorated. He suffered from fatigue, reduced exercise tolerance, weight loss and increased production of sputum, which on occasion was bloodstained. He had received three courses of antibiotics. His admission temperature was 37.5 C, blood pressure 150/100 mmHg, pulse rate 92 bpm regular, and respiratory rate 24 minÿ1 with prolonged expiration. Chest examination revealed coarse expiratory sounds throughout the lungs but nothing focal. The WBC was 13.5109 lÿ1 with 10.8109 lÿ1 neutrophils. Chest X-ray showed over-inflated lungs with extensive cystic bronchiectatic changes bilaterally and a shadowing in the right lower lobe. This raised the possibility of malignancy and the patient underwent a bronchoscopy, but no endobronchial lesions were seen. Cytological examination of the bronchial washings showed numerous polymorphs but no malignant cells. Contrast enhanced CT scan of the chest showed widespread bilateral bronchiectasis and no evidence of neoplasia. Gram stain of the bronchial washings and expectorated sputum showed numerous polymorphs, no epithelial cells and numerous Gram-negative bacilli. Auramine phenol stain and culture for mycobacteria were negative. Routine bacterial culture yielded a heavy pure growth of N. weaveri.
Case Reports The deterioration of the patient's condition, which necessitated his admission, was attributed to acute infective exacerbation of his bronchiectasis. Co-amoxiclav was commenced but was stopped due to side effects (nausea). He was then treated with a 3 weeks course of ofloxacin and had a good response. The sputum cleared and decreased in volume and his general condition improved. Sputum culture after treatment yielded normal respiratory flora only.
Isolation and Identification of N. weaveri Routine bacterial culture of patient's sputum and bronchial washings yielded a heavy pure growth of a Gram-negative rodshaped organism. Colonies on blood agar were 1±2 mm in diameter, entire, flat and non-pigmented at 24 h incubation. Growth on MacConkey agar was very poor, but the organism grew well on nutrient agar. The isolate was strongly oxidase and catalase positive, indole negative, non-motile and did not ferment carbohydrates. Identification based on phenotypic characteristics proved difficult, and the API NH and API20NE gave unacceptable profiles. Electron microscopy showed a rodshaped bacterium with no flagella. Nucleotide sequencing of the 16S rRNA gene was performed using the two universal primers (5 0 to 3 0 ) UN12 (GAC TCC TAC GGG AGG CAG CAG) and UN15 (CTG ATC CGC GAT TAC TAG CGA TTC) [3]. Partial sequencing (c. 1000 bp) of the 16S rRNA gene of the organism showed 97% homology with N. weaveri (GenBank AF395911) and 97% homology with Neisseria canis (GenBank L06170). However, identification of the organism as N. canis was discounted on morphologic criteria (N. canis is a coccus while our organism was a rod). The nucleotide sequence data reported here appear in the DDBJ/EMBL/GenBank database under accession number AF429995. The isolate was also examined for the presence of the following genes of the pathogenic Neisseria spp.: pil class I (using the primers 5 0 -ACC CTT ATC GAG CTG ATG AT-3 0 and 3 0 -TGA CGG CAG GTG CTT GGT G5 0 ), pil class II (using the primers 5 0 -TGC CCG CAT ACC AAG ACT AC-3 0 and 3 0 -CGG CAG GTA GAT GGC AAG AAT T-5 0 ), porA (primers 5 0 -TCC TTG GGA CAG CAA TAA T-3 0 and 3 0 TAG CTG ATG CGT GGA ACT-5 0 ) and IgA protease (primers 5 0 -CCG ATG ATT GAT TTT AGC GT-3 0 and 3 0 -CCA TTG GCA TCC CAA ACG AC-5 0 ) [F Al Rashidi, unpublished work], but the results were negative. Antibiotic susceptibility testing using the BSAC method showed the organism to be sensitive to penicillin, ciprofloxacin, erythromycin and gentamicin, but resistant to trimethoprim. The MIC of penicillin was 0.25 mg/l by E-test, and the chromogenic cephalosporin test for detection of -lactamase production was negative.
Discussion and Review of the Literature Neisseria weaveri is the name given in 1993 to CDC group M5 strains when on the basis of DNA hybridisation, 16S rRNA sequencing and biochemical characteristics it was elevated to the species level as a new species of the genus Neisseria [1,2]. 16S rRNA sequence analysis demonstrated that it belongs to the b-3 subgroup of proteobacteria, within the Neisseriaceae cluster [2]. It is an aerobic Gram-negative straight rod of
97
varying length, non-motile, strongly oxidase and catalase positive, and does not utilise carbohydrates. It grows well between 25 and 35 C and most strains grow at 42 C. Growth on MacConkey agar is slight and variable [1,2]. The organism is difficult to identify by conventional laboratory tests [4,5]. Neisseria weaveri is part of the normal canine oral flora. Isolation rates from the oral cavities of dogs range between 12% and 18% [1]. In humans, it has been isolated predominantly from infected dog bite wounds [1,2]. In a review of Moraxella-like organisms submitted for identification to CDC in the period from 1953 to 1980, 66 of the 74 group M-5 strains were from wounds, 53 from dog bites and none from a deep site of infection [6]. Despite its common occurrence in the oral cavities of dogs it is rather infrequently isolated from infected dog bite wounds. The prevalence of N. weaveri in infected animal bite wounds in humans has been reported as 4% in the US and 6% in France [4]. It has only rarely been recovered from human sites other than wounds. Of the 45 CDC group M-5 strains examined by Holmes et al. [1] one strain was isolated from the sputum of a diabetic patient but no other clinical information was given. In another study of 41 CDC group M-5 organisms [2], 68% were from dog bite wounds, one was an eye isolate and the only isolate from a deep-seated infection was from the peritoneal and chest fluid from a woman who had recently undergone pulmonary lobectomy. A case of septicaemia due to N. weaveri has been reported in an immunosuppressed patient with multiple myelomatosis [7]. In our patient, N. weaveri was isolated as a heavy pure growth from sputum and bronchial washings during an acute exacerbation of his bronchiectasis and it is likely that infection with this organism caused the deterioration in his chronic condition. The patient's health improved after antibiotic treatment and resultant eradication of the organism from his respiratory secretions. We do not know how the patient acquired the organism and whether he had any contact with dogs. To our knowledge, this is the first reported case of lower respiratory tract infection caused by N. weaveri.
Acknowledgements We thank Dr. P. Deegan, Consultant Physician in Respiratory Medicine at Royal Liverpool Hospital for allowing us to report on his patient.
References 1 Holmes B, Costas M, On SL, Vandamme P, Falsen E, Kersters K. Neisseria weaveri sp. nov. (formerly CDC Group M-5), from dog bite wounds of humans. Int J Syst Bacteriol 1993; 43: 687±693. 2 Andersen BM, Steigerwalt AG, O'Connor SP et al. Neisseria weaveri sp. nov., formerly CDC group M-5, a gram-negative bacterium associated with dog bite wounds. J Clin Microbiol 1993; 31: 2456±2466. 3 Mahenthiralingam E, Bischof J, Byrke SK et al. DNA-Based diagnostic approaches for identification of Burkholderia cepacia Complex, Burkholderia vietnamiensis, Burkholderia multivorans, Burkholderia stabilis, and Burkholderia cepacia genomovars I and III. J Clin Microbiol 2000; 38: 3165±3173. 4 Barnham M, Holmes B. Isolation of CDC group M-5 and Staphylococcus intermedius from infected dog bites. J Infect 1992; 25: 332±334.
98
Case Reports
5 Moss CW, Wallace PL, Hollis DG, Weaver RE. Cultural and chemical characterization of CDC groups EO-2, M-5, and M-6, Moraxella (Moraxella) species, Oligella urethralis, Acinetobacter species and Psychrobacter immobilis. J Clin Microbiol 1988; 26: 484±492. 6 Graham DR, Band JD, Thornsberry C, Hollis DG, Weaver RE. Infections caused by Moraxella, Moraxella urethralis, Moraxella-like groups
M-5 and M-6, and Kingella kingae in the United States, 1953±1980. Rev Infect Dis 1990; 12: 423±431. 7 Carlson P, Kontiainen S, Anttila P, Eerola E. Septicemia caused by Neisseria weaveri. Clin Infect Dis 1997; 24: 739.