Haemophilus aphrophilus discitis and vertebral osteomyelitis

Brain abscess due to Aggregatibacter aphrophilus in association with atrial septal defect：Case report and literature review

BACKGROUND

Aggregatibacter aphrophilus（A. aphrophilus）is one of the organisms of the HACEK group. Previously reported cases of brain abscesses caused by A. aphrophilus infection have occurred in children with a basis for congenital heart disease, or in adults with a basis for dental disease. Rare cases of brain abscess caused by A. aphrophilus have been reported in adults with congenital heart disease or in patients without dental disease history. Herein we present a rare case of brain abscess caused by A. aphrophilus, who was in association with atrial septal defect for more than 20 years, and had no dental disease and did not develop infective endocarditis.

CASE PRESENTATION

A 51-year-old female was admitted due to progressively worsening headache and left limb weakness for more than 10 days. She denied the history of chronic diseases such as hypertension and diabetes, and no periodontal disease. While she had a history of atrial septal defect, a form of congenital heart disease with severe pulmonary hypertension for more than 20 years. After admission, echocardiographic illustrated congenital heart disease with severe pulmonary hypertension. CT and MRI showed brain abscess. Cerebrospinal fluid (CSF) results also confirmed the presence of intracranial infection. Empirical therapy with vancomycin 1.0 g i.v q12h and meropenem 2.0 g i.v q8h was initiated from the day of admission. On the fourth day after admission, brain abscess resection and decompressive craniectomy were performed, and the pus drained on operation were cultured and Gram-negative bacilli grew, which was identified as A.aphrophilus. Vancomycin was discontinued and meropenem was continued（2.0 g i.v q8h）for 5 weeks, followed by oral levofloxacin 0.5 qd for 4 weeks of out-patient antibiotics. The patient recovered fully within 9 weeks of treatment.

CONCLUSIONS

This is the first case of A. aphrophilus to cause brain abscess in adult with a history of congenital heart disease for more than 20 years, who had no dental disease and did not develop infective endocarditis. We also highlight the value of bacterial 16 S rDNA PCR amplification and sequencing in identifying bacteria in abscesses which are culture-negative, and prompt surgical treatment，choosing effective antibiotics and appropriate course of treatment will get better clinical effect.

Aggregatibacter aphrophilus endocarditis: a case report

We present a case of endocarditis with embolic stroke and digital infarction due to the recently renamed Aggregatibacter aphrophilus. The isolation and identification of this organism can be problematic but was achieved in this case using both older phenotypic and newer genotypic methods. A benign tongue lesion is suggested as the likely portal of entry for this oropharyngeal organism. The patient made a good recovery with six weeks of intravenous ceftriaxone but will need cardiac valvular surgery at some point in the future.

Aggregatibacter aphrophilus in a patient with recurrent empyema: a case report

Introduction

Aggregatibacter aphrophilus (formerly Haemophilus aphrophilus and H. paraphrophilus) is classically associated with infective endocarditis. Other infections reported in the literature include brain abscess, bone and joint infections and endophthalmitis. There are only two cases of empyema ever reported due to this organism. We report the isolation of A. aphrophilus from pleural fluid on three separate hospital admissions in a patient with recurrent empyema.

Case presentation

A 65-year-old female patient of Caucasian origin presented with a three-week history of fever, shortness of breath and dry cough. She was found to have a pleural empyema so a chest drain was inserted and a sample of pus was sent to the microbiology laboratory. After overnight incubation, a chocolate blood agar plate incubated in 5% carbon dioxide showed a profuse growth of small, round, glistening colonies which were identified as Gram-negative coccobacilli. They were oxidase- and catalase-negative. Biochemical testing using RapID NH confirmed the identity of the organism as A. aphrophilus. It was susceptible to amoxicillin, levofloxacin and doxycycline. Our patient was treated with intravenous amoxicillin with clavulanic acid and clarithromycin followed by oral doxycycline, but was re-admitted twice over the next three months with recurrent empyema and the same organism was isolated. Each episode was managed with chest drainage and a six-week course of antibiotic--doxycycline for the second episode and amoxicillin for the third episode, after which she has remained well.

Conclusion

This is the first case report of recurrent empyema due to A. aphrophilus. Our patient had no underlying condition to explain the recurrence. Although our isolate was doxycycline susceptible, our patient had recurrent infection after treatment with this antibiotic, suggesting that this antibiotic is ineffective in treatment of deep-seated A. aphrophilus infection. This organism can be difficult to identify in the laboratory because, unlike closely related Haemophilus spp., it is oxidase-negative, catalase-negative and X and V independent.

Epidural abscess caused by Haemophilus aphrophilus misidentified as Pasteurella species

Haemophilus aphrophilus is one of the normal oropharyngeal flora and rarely implicated as a pathogen of spinal infection. A case of H. aphrophilus bacteremia complicated with epidural abscess, psoas muscle abscess, and spondylodiscitis is described in this report. The pathogen was mis-identified as Pasteurella spp. at the very start, and was confirmed by the molecular method. He was successfully treated with adequate antibiotics and surgery. The clinical features of sixteen previously reported cases of spinal infection caused by H. aphrophilus are reviewed.

Vertebral infections caused by Haemophilus aphrophilus: case report and review

OBJECTIVE

To review in detail clinical presentation, bacteriologic findings, associated conditions and treatment of Haemophilus aphrophilus vertebral osteomyelitis and to compare them to a case we report herein.

METHODS

A Medline (National Library of Medicine) search of the literature was performed by using the key words H. aphrophilus, spondylodiscitis, discitis, and vertebral osteomyelitis. The references of the case reports were examined for additional cases, especially those cited in older articles that had not been entered onto the bibliographic database.

RESULTS

A case report of spondylodiscitis due to H. aphrophilus in a 35-year-old patient with a history of dental abscess 7 months before admission is presented. The patient responded well to treatment with ceftriaxone and ciprofloxacin. To date, only 14 cases of H. aphrophilus vertebral osteomyelitis have been reported. They are usually reported in middle-aged patients, usually male. Most recent cases have been treated with fluoroquinolones. Duration of treatment usually ranges from 1 to 3 months.

CONCLUSIONS

H. aphrophilus is an uncommon cause of vertebral osteomyelitis. Patients are regularly cured by antibiotic therapy, provided that a tissue biopsy is performed in order to isolate the causative bacterium.

Haemophilus aphrophilus meningitis complicated by hydrocephalus in an immunocompetent adult

A case of meningitis due to an unusual organism, Haemophilus aphrophilus in an adult is described. In spite of rapid clearance of the organism from the cerebrospinal fluid with intravenous cefotaxime, fever persisted over 8 days of therapy and infection was complicated by hydrocephalus. H. aphrophilus meningitis is uncommon and has not been previously reported in an adult male.

Haemophilus aphrophilus bacteraemia complicated with vertebral osteomyelitis and spinal epidural abscess in a patient with liver cirrhosis

Haemophilus aphrophilus is rarely implicated as an aetiology of spinal epidural abscess. A 73-year-old woman with liver cirrhosis who developed H. aphrophilus bacteraemia complicated with vertebral osteomyelitis and spinal epidural abscess is presented. Without surgical decompression, she was successfully treated with cefotaxime for 3 weeks, followed by maintenance with ciprofloxacin for another 10 weeks. The clinical features of eight previously reported cases of vertebral osteomyelitis without epidural abscess due to H. aphrophilus are reviewed.