Brain Abscess Formation Research Articles

Brain Abscess Complicating an Intracranial Hemorrhage

Problem statement: A brain abscess presenting after an Intracranial Hemorrhage (ICH) is an extremely rare occurrence. Diagnosis in this setting is difficult, given the absence of key clinical features, such as neurologic deficit and headaches. Since a delay in the diagnosis of a brain abscess leads to poor outcomes, there should be a high index of suspicion for abscess in patients developing fever after an ICH. Approach: This is a case report describing the presentation, hospital course and management of a patient who was diagnosed with a brain abscess following an ICH. Results: A review of literature revealed only 15 such cases. The basal ganglia are the most common sites of infection. The mean interval between the ICH and the systemic infection which resulted in an abscess was 9.8 days. Time from infection to brain abscess formation was 8-140 days, with a mean of 20 days. There was a delay in diagnosis in earlier case reports. Conclusion: Although brain abscess is a rare complication after ICH, because of the high mortality and morbidity, it should be considered in patients who develop fever after ICH.

Brain Abscess Formation Accompanied by Improvement of Orbital Cellulitis

Purpose: To present a case of brain abscess formation accompanied by improvement of orbital cellulitis. Case summary: A 54-year-old male came to our clinic complaining of swelling and pain of the left periorbital area and decreased visual acuity (VA) of the left eye. Initial best-corrected visual acuity (BCVA) was 0.3 and intraocular pressure was 27 mmHg in the left eye. Eye movement in all directions was restricted and 4 mm of proptosis was observed in the left eye. An orbital CT scan demonstrated pansinusitis and orbital cellulitis of the left eye. The patient underwent endoscopic sinus surgery and was treated with systemic antibiotics. However, periorbital swelling was aggravated and another orbital CT scan was performed and analyzed. The CT scan showed localized periorbital abscess of the left eye, and the authors performed an incision and drainage (I&D) of abscess procedure. After the operation, BCVA of the left eye was recovered to 0.8 and eye movement improved and periorbital swelling decreased. However, 15 days after the I&D, the patient complained of a severe headache. Brain magnetic resonance imaging (MRI) was performed and showed an abscess of the left frontal lobe of the brain. The authors consulted with a neurosurgeon, and the patient received intravenous antibiotics and mannitol. The headache steadily decreased, and three months after the first visit, a follow-up brain MRI was performed. The MRI showed almost complete disappearance of the abscess and six months after the first visit, BCVA was recovered to 1.0 and eye movement was full in all directions. Conclusions: Although orbital cellulitis is improved by treatment of antibiotics and surgery, if the patient complains of neurologic symptoms such as headache, other complications such as brain abscess formation should be considered.

Brain Abscess Formation within an Endodermal Cyst of the Frontal Lobe: Case Report

A 38-year-old man with a right frontal lobe cyst was treated by endoscopic cystoventriculostomy in 1998. Cyst capsule histology revealed surprisingly an endodermal cyst. The patient was reoperated for cyst expansion by endoscopic re-cystoventriculostomy in 2005. In 2007, the patient suffered from brain abscess formation within the cyst which was punctured. The history was positive for a dental infection. In 2008, a recurrent brain abscess in the cyst occurred. The cyst was completely resected. There was no history of trauma or sinusitis. In all, endodermal cysts may mimic a paraxial arachnoid cyst. It may predispose for recurrent brain abscess formation - especially due to bacteraemia. This report confirms earlier presentations that endodermal cysts should be resected, and endoscopic cyst opening is not sufficient.

An unusual mechanism for brain abscess formation in a child

Intracranial infection is an uncommon but serious complication of head injury. This study describes a boy with a traumatic head injury caused by his mother's teeth stemming from a traffic accident, without initial alteration of consciousness or focal neurological signs, who subsequently developed an occipital lobe abscess 3 weeks later. Brain abscess culturing yielded human oral flora. To date, our case is the only report documenting skull fracture with subsequent brain abscess formation caused by human oral flora stemming from traumatic injury from his mother's teeth. A high index of suspicion should be maintained, and early imaging such as computed tomography should be considered for patients with symptoms of intracranial infection or who are at high risk, even after a minor head injury. Early diagnosis, appropriate antibiotic therapy based on knowledge of the causative microbes, and surgery are the major prognostic factors for brain abscess.

Brain abscess formation as a CSF shunt complication: a case report

The formation of a brain abscess as a result of a cerebrospinal fluid shunt complication is extremely rare in the literature with only 7 cases reported in the last 20 years. We report a patient that developed a brain abscess adjacent to a functioning ventricular catheter in the presence of shunt infection by another pathogen. Clinicians should consider this complication in any shunted patient with clinical features of infection and suggestive changes on imaging however subtle. Expedited standard management for the abscess and the CSF shunt infection, if present, should be employed. Removal of all non-functioning catheters should be encouraged.

Brain abscess and granuloma formation as late complications of retained ventricular catheter

This report presents a rare complication of ventriculoperitoneal shunt, delayed development of brain abscess and foreign body granuloma formation adjacent to the intraventricular catheter. Both the complications occurring in the same patient is unusual.

Complications of Carotid Blowout Syndrome in Patients with Head and Neck Cancers Treated by Covered Stents

The purpose of this study was to improve clinical assessment of carotid-blowout syndrome (CBS) in patients with head-and-neck cancers and with covered stents by evaluating immediate and delayed complications of reconstructive management. Eleven such patients were treated with self-expandable covered stents. We evaluated immediate and delayed complications by assessing clinical and imaging findings. Technical success and immediate hemostasis were achieved in all patients. Immediate complications were noted in four patients (36.4%), including thromboembolism in three patients and, in one patient, dissection of the carotid artery and type III endoleak by the overlapped self-expandable stent causing rebleeding. Delayed complications were noted in eight patients (72.7%), including six episodes of rebleeding in five patients, distal marginal stenosis in five patients, and delayed carotid thrombosis in three patients (one with brain abscess formation). We suggest close follow-up of the patients and aggressive re-intervention of their complications to improve outcomes.

Brain abscess formation at the site of intracerebral hemorrhage secondary to central nervous system vasculitis

Brain abscess is a rare but very dangerous neurosurgical lesion. Prompt diagnosis and emergency surgical evacuation are the hallmarks of therapy. Brain abscess following ischemic and hemorrhagic stroke is a rare entity. These cases are often preceded by episodes of bacteremia, sepsis, and local infection. The authors report the case of a 30-year-old woman who presented with a cerebral abscess at the site of a recent intraparenchymal hemorrhage.

Neisseria elongata endocarditis complicated by brain embolism and abscess

We report a case of Neisseria elongata endocarditis with thalamic septic embolization and subsequent brain abscess formation, which to the best of our knowledge has never been reported in the literature. The brain abscess completely resolved after a surgical repair of the infected mitral valve and an additional 4 weeks of antimicrobial therapy. Based on a review of all previous reports of N. elongata endocarditis, including ours, this will remind physicians that invasive N. elongata infections should be managed and followed up cautiously, as surgical intervention is often required.

Enterobacter sakazakii invades brain capillary endothelial cells, persists in human macrophages influencing cytokine secretion and induces severe brain pathology in the neonatal rat

Enterobacter sakazakii is an opportunistic pathogen associated with contaminated powdered infant formula and a rare cause of Gram-negative sepsis that can develop into meningitis and brain abscess formation in neonates. Bacterial pathogenesis remains to be fully elucidated. In this study, the host inflammatory response was evaluated following intracranial inoculation of Ent. sakazakii into infant rats. Infiltrating macrophages and neutrophils composed multiple inflammatory foci and contained phagocytosed bacteria. Several genotypically distinct Ent. sakazakii strains (16S cluster groups 1-4) were shown to invade rat capillary endothelial brain cells (rBCEC4) in vitro. Further, the persistence of Ent. sakazakii in macrophages varied between strains. The presence of putative sod genes and SOD activity may influence the survival of acidic conditions and macrophage oxidase and contribute to Ent. sakazakii intracellular persistence. The influence of macrophage uptake of Ent. sakazakii on immunoregulatory cytokine expression was assessed by ELISA. This demonstrated that the IL-10/IL-12 ratio is high after 24 h. This is suggestive of a type 2 immune response which is inefficient in fighting intracellular infections. These findings may help explain how the diversity in virulence traits among Ent. sakazakii isolates and an unsuccessful immune response contribute to the opportunistic nature of this infection.

Brain Abscess after Esophageal Dilatation: Case Report

Brain abscess formation is a serious disease often seen as a complication to other diseases and to procedures. A rare predisposing condition is dilatation therapy of esophageal strictures. A case of brain abscess formation after esophageal dilatations is presented. A 59-year-old woman was admitted with malaise, progressive lethargy, fever, aphasia and hemiparesis. Six days before she had been treated with esophageal dilatation for a stricture caused by accidental ingestion of caustic soda. The brain abscess was treated with surgery and antibiotics. She recovered completely. This clinical case illustrates the possible association between therapeutic esophageal dilatation and the risk of brain abscess formation.

Brain abscess following intracerebral haemorrhage

A 79-year old male patient developed a brain abscess as infective transformation of a preceding intracerebral haemorrhage after urinary tract infection. The awareness of brain abscess formation at the site of intracerebral haemorrhage is crucial for early diagnosis and treatment of this rare but potentially fatal complication.

Randomized Controlled Trial of Pyrimethamine Plus Sulfadiazine Versus Trimethoprim Plus Sulfamethoxazole for Treatment of Toxoplasmic Encephalitis in AIDS Patients

Toxoplasmic encephalitis (TE), caused by Toxoplasma gondii, is common in AIDS patients. TE can result in tissue destruction via massive inflammation and brain abscess formation. Randomized controlled trials were performed in AIDS patients to assess which drug regimen was optimally effective for the treatment of TE. AIDS patients with TE were randomly divided into 3 groups that received a 6-week course of either pyrimethamine (50 mg/day or 100 mg/day) plus sulfadiazine (4 g/day) and folinic acid (25 mg/day) or trimethoprim (10 mg/kg/day) plus sulfamethoxazole (50 mg/kg/day) (TMP-SMX), and results were evaluated with respect to clinical response, mortality, morbidity, and serious adverse events. The primary outcome was defined as death in the first 6-week period. The secondary outcome was successful treatment within 6 weeks without severe adverse events, bone marrow suppression, drug-induced rash, or any other event that caused a change in the treatment regimen. The results from this study showed that in AIDS patients, TE was most successfully treated with the combination of pyrimethamine (50 mg/day) plus sulfadiazidine (4 g/day) and folinic acid (25 mg/day); failure rates were not significantly different among the 3 treatment groups. Available data suggest that of the currently available options, treatment of TE with pyrimethamine at 50 mg/day plus sulfadiazidine at 4 g/day provides the best primary outcome for AIDS patients with TE; however, because this study was terminated prematurely, we suggest that treatment with intravenous TMP-SMX be further evaluated to determine its efficacy.

FliP influences Citrobacter koseri macrophage uptake, cytokine expression and brain abscess formation in the neonatal rat

Citrobacter koseri causes neonatal meningitis frequently complicated with multiple brain abscesses. During C. koseri central nervous system infection in the neonatal rat model, previous studies have documented many bacteria-filled macrophages within the neonatal rat brain and abscesses. Previous studies have also shown that C. koseri is taken up by, survives phagolysosomal fusion and replicates in macrophages in vitro and in vivo. In this study, in order to elucidate genetic and cellular factors contributing to C. koseri persistence, a combinatory technique of differential fluorescence induction and transposon mutagenesis was employed to isolate C. koseri genes induced while inside macrophages. Several banks of mutants were subjected to a series of enrichments to select for gfp : : transposon fusion into genes that are turned off in vitro but expressed when intracellular within macrophages. Further screening identified several mutants attenuated in their recovery from macrophages compared with the wild-type. A mutation within an Escherichia coli fliP homologue caused significant attenuation in uptake and hypervirulence in vivo, resulting in death within 24 h. Furthermore, analysis of the immunoregulatory interleukin (IL)-10/IL-12 cytokine response during infection suggested that C. koseri fliP expression may alter this response. A better understanding of the bacteria-macrophage interaction at the molecular level and its contribution to brain abscess formation will assist in developing preventative and therapeutic strategies.

Conservative management of a brain abscess in a patient with Staphylococcus lugdunensis endocarditis

Brain abscess is defined as a focal, intracerebral infection that begins as a localized area of cerebritis and develops into a collection of pus surrounded by a well-vascularized capsule. Microorganisms can gain access to the brain through several mechanisms, most commonly by direct extension of an adjacent suppurative focus (i.e. otitis media, mastoiditis, or sinusitis) or by direct penetration via an open cerebrospinal fluid leak (e.g. after cranial fracture or neurosurgical complication). Another mechanism of brain abscess formation is hematogenous bacterial spread from a distant focus of infection, such as endocarditis. Despite the presence of continuous bacteremia, brain abscess is an uncommon complication after bacterial endocarditis [1] (less than 5% of cases in most series). However, endocarditis due to Staphylococcus lugdunensis follows a more fulminant course, typically resulting in either cardiac complications or systemic emboli with metastatic foci of infection. Optimal handling of patients with bacterial infections of the central nervous system often requires surgical management; nonetheless, a subset of patients may be treated with appropriate antimicrobial therapy alone [2–4]. In this setting, the choice of antibiotic agents should be based on the results of susceptibility testing and the drug’s cerebrospinal fluid penetration. Here, we report a case of brain abscess in a patient with S. lugdunensis endocarditis involving a native bicuspid aortic valve. We also review the literature regarding the conservative management of brain abscesses in this clinical setting. A 49-year-old woman with an unremarkable medical history was admitted to our hospital with fever of 39°C, right-sided hemiparesis and aphasia. Computed tomography (CT) scan of the brain suggested an ischemic lesion of the left external capsule. S. lugdunensis was isolated from all four of the blood cultures taken upon admission. The organism was shown to be susceptible to all antibiotics tested. A transesophageal echocardiograph (TEE) confirmed the presence of large vegetations (12×4 mm) on the bicuspid aortic valve and subsequent regurgitation due to aortic valve destruction. The diagnosis of endocarditis due to S. lugdunensis involving a bicuspid aortic valve with severe aortic valve insufficiency and embolic septic cerebrovascular insult was established. Antibiotic therapy with flucloxacillin (2 g iv q4h), supplemented with gentamicin (80 mg iv tid) for the first 5 days, was started. Body temperature, neurological deficiencies and inflammatory laboratory values normalized rapidly and the patient remained hemodynamically stable. After 6 weeks of antibiotic therapy, TEE showed persistent aortic valve vegetation and an increased diastolic diameter of the left ventricle (EDVI: 63 ml/m). Valve replacement was subsequently recommended. A second CT scan (Fig. 1) performed during the pre-operative investigation revealed the presence of a small abscess (1 cm in diameter) at the level of the left insula. Given the size of the abscess, the lack of neurological symptoms and the known tendency toward development of metastatic lesion secondary to S. lugdunensis bacteremia, surgical abscess excision was deferred. Because of its optimal ability to penetrate the blood brain barrier, rifampin (600 mg orally bid) was added to the antibiotic regimen. Eur J Clin Microbiol Infect Dis (2006) 25:476–478 DOI 10.1007/s10096-006-0169-0

Metallic Foreign Body in the Cavernous Sinus Causing Delayed Formation of Brain Abscess After Missile Injury

Metallic Foreign Body in the Cavernous Sinus Causing Delayed Formation of Brain Abscess After Missile Injury

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Bilateral Osteomyelitis following frontal sinusitis is a rare complication in the antibiotic era. The main risk of a progredient course is mainly the formation of external subperiostal, epidural, subdural abscesses or brain abscesses with potentially life-threatening complications. This is a report on a patient who presented in our department with progredient cephalgia and swelling in the area around the glabella and frontal sinus. Macroscopical examination revealed septum deviation to the right side and nasal polyposis of the right nasal passage. A computed tomography of the paranasal sinuses showed subtotal soft tissue obstruction of all sinuses with the exception of the sphenoidal sinus. Bilateral osteolysis of the ventral osseous borders of the frontal sinus with accompanying osteosclerosis was also observed. The therapy consisted of radical frontal sinus surgery via Unterberger approach. This case demonstrates a rare case of bilateral frontal osteomyelitis together with the necessary diagnostic and therapeutic measures. The management consisted of the removal of all osteomyelitic bone and antibiotic therapy. Differential diagnostic procedures must be carried out in order to exclude orbital and intracranial complications. Regular follow-up examinations and a CT scan of the paranasal sinuses are part of the standard therapy.

Citrobacter koseri brain abscess in the neonatal rat: survival and replication within human and rat macrophages.

A unique feature of Citrobacter koseri is the extremely high propensity to initiate brain abscesses during neonatal meningitis. Previous clinical reports and studies on infant rats have documented many Citrobacter-filled macrophages within the ventricles and brain abscesses. It has been hypothesized that intracellular survival and replication within macrophages may be a mechanism by which C. koseri subverts the host response and elicits chronic infection, resulting in brain abscess formation. In this study, we showed that C. koseri causes meningitis and brain abscesses in the neonatal rat model, and we utilized histology and magnetic resonance imaging technology to visualize brain abscess formation. Histology and electron microscopy (EM) revealed that macrophages (and not fibroblasts, astrocytes, oligodendrocytes, or neurons) were the primary target for long-term C. koseri infection. To better understand C. koseri pathogenesis, we have characterized the interactions of C. koseri with human macrophages. We found that C. koseri survives and replicates within macrophages in vitro and that uptake of C. koseri increases in the presence of human pooled serum in a dose-dependent manner. EM studies lend support to the hypothesis that C. koseri uses morphologically different methods of uptake to enter macrophages. FcgammaRI blocking experiments show that this receptor primarily facilitates the entry of opsonized C. koseri into macrophages. Further, confocal fluorescence microscopy demonstrates that C. koseri survives phagolysosomal fusion and that more than 90% of intracellular C. koseri organisms are colocalized within phagolysosomes. The ability of C. koseri to survive phagolysosome fusion and replicate within macrophages may contribute to the establishment of chronic central nervous system infection including brain abscesses.

Diminished Virulence of an Alpha-Toxin Mutant ofStaphylococcus aureusin Experimental Brain Abscesses

Staphylococcus aureus is one of the major etiologic agents of brain abscesses in humans, occasionally leading to focal neurological deficits and even death. The objective of the present study was to identify key virulence determinants contributing to the pathogenesis of S. aureus in the brain using a murine brain abscess model. The importance of virulence factor production in disease development was demonstrated by the inability of heat-inactivated S. aureus to induce proinflammatory cytokine or chemokine expression or brain abscess formation in vivo. To directly address the contribution of virulence determinants in brain abscess development, the abilities of S. aureus strains with mutations in the global regulatory loci sarA and agr were examined. An S. aureus sarA agr double mutant exhibited reduced virulence in vivo, as demonstrated by attenuated proinflammatory cytokine and chemokine expression and bacterial replication. Subsequent studies focused on the expression of factors that are altered in the sarA agr double mutant. Evaluation of an alpha-toxin mutant revealed a phenotype similar to that of the sarA agr mutant in vivo, as evidenced by lower bacterial burdens and attenuation of cytokine and chemokine expression in the brain. This suggested that alpha-toxin is a central virulence determinant in brain abscess development. Another virulence mechanism utilized by staphylococci is intracellular survival. Cells recovered from brain abscesses were shown to harbor S. aureus intracellularly, providing a means by which the organism may establish chronic infections in the brain. Together, these data identify alpha-toxin as a key virulence determinant for the survival of S. aureus in the brain.

Detection of an intense resonance at 2.4 ppm in 1H MR spectra of patients with severe late-delayed, radiation-induced brain injuries.

Proton MRS and MRI were used to monitor the progression of severe cerebral radiation injuries in 10 patients over a period of 18 months. An unknown resonance (Px) in the 2.37-2.40 ppm region was consistently detected in the affected temporal lobes of four patients. The detection of Px was only confined to spectra with lactate (Lac) and in patients with the highest severity grading of radiation injury. The incidence of Px in Lac-positive spectra was 42.8% (15/35) and in lesions with highest injury grading was 46.8% (15/32). Lesions with Px had significantly higher Lac/creatine (Cr) ratios and more extensive mass effect changes when compared to lesions without Px. The probable identity of Px was examined in the context of anaerobic glycolysis producing pyruvate (2.37 ppm) and the model of metabolic changes in brain abscess formation implicating succinate (2.40 ppm).