Successful medical treatment of intracranial abscess caused by Brucella spp

Neurobrucellosis presenting as an infected cerebellopontine cistern epidermoid cyst

Neurobrucellosis is a rare complication of brucella infection which presents as meningitis, meningoencephalitis, subdural empyema, brain abscess, myelitis, and radiculo- neuritis. We report the first case of neurobrucellosis presenting as an infected cerebellopontine cistern epidermoid cyst in a young immunocompetent male who presented with fever and acute raised intracranial pressure. MRI brain showed an extra-axial mass in the right cerebellopontine angle cistern with peripheral rim enhancement and diffusion restriction. Emergency surgery unveiled a well-encapsulated lesion containing thick pus and keratinous material, confirming an infected epidermoid cyst. Intriguingly, the culture revealed Brucella infection, but the source of the infection remained unclear.

Treatment of a subdural empyema complicated by intracerebral abscess due to Brucella infection

A 55-year-old male presented with fever, stupor, aphasia, and left hemiparesis. A history of head trauma 3 months before was also reported. Cranial magnetic resonance imaging revealed slight contrast enhancement of lesions under the right frontal skull plate and right frontal lobe. Because of deterioration in nutritional status and intracranial hypertension, the patient was prepared for burr hole surgery. A subdural empyema (SDE) recurred after simple drainage. After detection of Brucella species in SDE, craniotomy combined with antibiotic treatment was undertaken. The patient received antibiotic therapy for 6 months (two doses of 2 g ceftriaxone, two doses of 100 mg doxycycline, and 700 mg rifapentine for 6 months) that resulted in complete cure of the infection. Thus, it was speculated that the preexisting subdural hematoma was formed after head trauma, which was followed by a hematogenous infection caused by Brucella species.

Epidemiological and clinical characteristics of neurobrucellosis case patients in Tunisia

OBJECTIVE

We aimed to identify epidemiological, clinical, therapeutic, diagnostic, and outcome characteristics of neurobrucellosis case patients in Tunisia.

PATIENTS AND METHODS

We conducted a retrospective and descriptive study over a 17-year period (January 1997-December 2013). We included all neurobrucellosis patients hospitalized in the infectious disease department of La Rabta Hospital of Tunis during the study period.

RESULTS

A total of 13 patients were included in the study: 9 men and 4 women. Mean age was 31.6 years. Six patients presented with meningitis, three with encephalitis, two with meningoencephalitis, and two with meningo-myeloradiculitis. All patients had a lumbar puncture performed. Eleven patients had an abnormal cerebrospinal fluid (CSF) (84.6%): lymphocytic pleocytosis in seven patients, high level of CSF proteins in 11, and low level of CSF glucose in seven. All patients had a positive Brucella serological test in blood. A Brucella serological test was also performed in CSF and was positive for 10 patients (77%). A total of nine patients had a cerebral CT scan and/or MRI performed and abnormalities were observed in six patients. Antibiotic therapy was prescribed to all patients: a combination of rifampicin and co-trimoxazole (n=9) or doxycycline (n=4) for an average duration of eight months. Two patients also received steroids. A positive outcome was observed in 10 patients. Three patients were lost to follow up.

CONCLUSION

Brucellosis may be severe when neurological involvement occurs. Brucellosis should be considered in the event of any neurological involvement associated with suggestive epidemiological features.

Principles of Antibiotic Penetration into Abscess Fluid

Although drainage is considered the gold standard in abscess treatment, abscesses of different sizes and locations have been successfully cured by means of antibiotic treatment alone. The penetration of an antibiotic into an encapsulated purulent lesion is limited and highly dependent on the degree of abscess maturation. In fact, in vivo pharmacokinetic data demonstrate that substantial antibiotic concentrations can be reached within abscesses in humans and animals, provided the choice of an appropriate agent and an optimal dosing regimen. However, the efficacy of antibiotics in pus may be hampered by various factors like low pH, protein binding and degradation by bacterial enzymes. This article provides a comprehensive review on conservative abscess treatment, presenting clinical data on success rates of antibiotic therapy. Antibiotic concentrations measured in abscesses of humans and animals are outlined, and theoretical considerations on the understanding of pharmacokinetics and efficacy of antibiotics in abscesses are discussed.