Brain abscess in immunocompetent adult patients

Community-Acquired Solitary Brain Abscesses Caused by Hypervirulent Klebsiella pneumoniae in a Healthy Adult

A 42-year-old man was admitted to the emergency room complaining of fever and headache. His cerebrospinal fluid showed a cloudy appearance, and his white blood cell count was elevated at 2460/mm3, with a predominance of neutrophils (81%), and abnormal protein and glucose levels (510.7 mg/dL and 5 mg/dL, respectively). A lobulated lesion with rim enhancement, suggestive of abscess, was detected through magnetic resonance imaging. Klebsiella pneumoniae was detected in nasopharyngeal swab and blood cultures. The capsular serotype of K. pneumoniae was K2 and the sequence type determined by multilocus sequence typing was 23. The hypervirulent phenotype was associated with multiple virulent genes, including rmpA, rmpA2, entB, ybtS, kfu, iucA, iutA, iroB mrkD, allS, peg-344, peg-589, and peg-1631. After six weeks of receiving appropriate antibiotics and exhibiting clinical resolution of the brain abscesses, the patient was discharged. We present the first reported case of a healthy community-dwelling adult with solitary brain abscesses, and no other invasive abscesses, related to hypervirulent K. pneumoniae.

Peculiar Case of Brain Abscess Caused by Propionibacterium acnes in an Immunocompetent Individual Without Prior Neurosurgical Intervention: A Case Report and Literature Review

Propionibacterium acnes (P. acnes) is a slow-growing, anaerobic, gram-positive bacillus that commonly colonizes the skin and is a rare cause of CNS infections. It was previously viewed as a culture contaminant but is now recognized to infrequently cause indolent cases of CNS infections. It is even more rarely associated with abscesses in patients without a prior history of neurosurgical intervention. Due to being a slow-growing bacteria, P. acnes is frequently discovered to be the causative organism after 16S rRNA sequencing. In this case, the culture was positive. There are only five other reported cases of patients with a P. acnes abscess without prior neurosurgical intervention. Here we present the sixth case of an immunocompetent young male who was found to have a P. acnes brain abscess.

Fatal Orbital Cellulitis With Intracranial Abscess: A Case Report

Orbital cellulitis is a sight- and life-threatening condition. Prompt diagnosis and immediate intervention are required. We report a case of fatal odontogenic orbital cellulitis complicated with intracranial abscesses in a 55-year-old gentleman. The patient presented with painful swelling of the left eye associated with reduced eye movement, blurry vision, and a headache. There was generalized periodontitis. Initial imaging was suggestive of left eye orbital cellulitis with intracranial abscess, and intensive systemic antibiotic therapy was initiated. After six weeks of antibiotic therapy, there was an improvement in ocular signs and symptoms. However, the patient developed signs of meningism with a persistent fever. Serial brain imaging demonstrated worsening intracranial abscesses. The patient died eight weeks after the initial onset of presentation. This case emphasized that brain abscesses could be a fatal complication of odontogenic orbital cellulitis. A high index of suspicion is important in diagnosing orbital cellulitis and its complications. Early consideration of surgical intervention is necessary in cases not responding to antibiotic therapy.

Proposal of a Method for Transferring High-Quality Scientific Literature Data to Virtual Patient Cases Using Categorical Data Generated by Bernoulli-Distributed Random Values: Development and Prototypical Implementation

BACKGROUND

Teaching medicine is a complex task because medical teachers are also involved in clinical practice and research and the availability of cases with rare diseases is very restricted. Automatic creation of virtual patient cases would be a great benefit, saving time and providing a wider choice of virtual patient cases for student training.

OBJECTIVE

This study explored whether the medical literature provides usable quantifiable information on rare diseases. The study implemented a computerized method that simulates basic clinical patient cases utilizing probabilities of symptom occurrence for a disease.

METHODS

Medical literature was searched for suitable rare diseases and the required information on the respective probabilities of specific symptoms. We developed a statistical script that delivers basic virtual patient cases with random symptom complexes generated by Bernoulli experiments, according to probabilities reported in the literature. The number of runs and thus the number of patient cases generated are arbitrary.

RESULTS

We illustrated the function of our generator with the exemplary diagnosis "brain abscess" with the related symptoms "headache, mental status change, focal neurologic deficit, fever, seizure, nausea and vomiting, nuchal rigidity, and papilledema" and the respective probabilities from the literature. With a growing number of repetitions of the Bernoulli experiment, the relative frequencies of occurrence increasingly converged with the probabilities from the literature. For example, the relative frequency for headache after 10.000 repetitions was 0.7267 and, after rounding, equaled the mean value of the probability range of 0.73 reported in the literature. The same applied to the other symptoms.

CONCLUSIONS

The medical literature provides specific information on characteristics of rare diseases that can be transferred to probabilities. The results of our computerized method suggest that automated creation of virtual patient cases based on these probabilities is possible. With additional information provided in the literature, an extension of the generator can be implemented in further research.

Spontaneous empyema and brain abscess in an intensive care population: clinical presentation, microbiology, and factors associated with outcome

BACKGROUND

Data on critically ill patients with spontaneous empyema or brain abscess are limited. The aim was to evaluate clinical presentations, factors, and microbiological findings associated with the outcome in patients treated in a Neurocritical Care Unit.

METHODS

In this retrospective study, we analyzed 45 out of 101 screened patients with spontaneous epidural or subdural empyema and/or brain abscess treated at a tertiary care center between January 2012 and December 2019. Patients with postoperative infections or spinal abscess were excluded. Medical records were reviewed for baseline characteristics, origin of infection, laboratory and microbiology findings, and treatment characteristics. The outcome was determined using the Glasgow outcome scale extended (GOSE).

RESULTS

Favorable outcome (GOSE 5-8) was achieved in 38 of 45 patients (84%). Four patients died (9%), three remained severely disabled (7%). Unfavorable outcome was associated with a decreased level of consciousness at admission (Glasgow coma scale < 9) (43% versus 3%; p = 0.009), need of vasopressors (71% versus 11%; p = 0.002), sepsis (43% versus 8%; p = 0.013), higher age (65.1 ± 15.7 versus 46.9 ± 17.5 years; p = 0.014), shorter time between symptoms onset and ICU admission (5 ± 2.4 days versus 11.6 ± 16.8 days; p = 0.013), and higher median C-reactive protein (CRP) serum levels (206 mg/l, range 15-259 mg/l versus 17.5 mg/l, range 3.3-72.7 mg/l; p = 0.036). With antibiotics adapted according to culture sensitivities in the first 2 weeks, neuroimaging revealed a progression of empyema or abscess in 45% of the cases.

CONCLUSION

Favorable outcome can be achieved in a considerable proportion of an intensive care population with spontaneous empyema or brain abscess. Sepsis and more frequent need for vasopressors, associated with unfavorable outcome, indicate a fulminant course of a not only cerebral but systemic infection. Change of antibiotic therapy according to microbiological findings in the first 2 weeks should be exercised with great caution.

Streptococcus constellatus causing concomitant extra and intracranial abscesses complicated with sagittal sinus thrombosis

Streptococcus constellatus is a gram-positive coccus member of the Streptococcus anginosus group (SAG). It can be found in the oral flora, and may cause abscess more commonly in the gastrointestinal tract, lungs, and heart. Brain abscesses are severe neurological infections with high mortality rates. Streptococcus species other than S. pneumoniae are rare causes of brain abscesses. This case report highlights a severe case of extra and intracranial abscesses due to S. constellatus in an immunocompetent host.

Intramedullary spinal cord abscess with brain abscess due to subacute infective endocarditis

BACKGROUND

Intramedullary spinal cord abscesses (ISCA) are rare, even more so in association with brain abscesses. Infective endocarditis is an uncommon cause of ISCA. In this case study, we report a patient with intramedullary abscesses and multiple brain abscesses due to subacute infective endocarditis.

CASE PRESENTATION

A 54-year-old man presented with a 7-day history of head and neck pain and numbness in both lower limbs. Intramedullary abscess combined with multiple brain abscesses was diagnosed based on blood culture, head and spinal magnetic resonance imaging (MRI), contrast-enhanced MRI, and magnetic resonance spectroscopy. Echocardiography revealed vegetations on the mitral valve and severe mitral regurgitation, which the authors believe was caused by subacute infective endocarditis. With ceftriaxone combined with linezolid anti-infective therapy, the patient's symptoms and imaging was improved during follow-up.

CONCLUSIONS

This case hopes to raise the vigilance of clinicians for ISCA. When considering a patient with an ISCA, it is necessary to complete blood culture, MRI of the brain and spinal cord, and echocardiography to further identify whether the patient also has a brain abscess and whether the cause is infective endocarditis.

Outcome of medical treatment of otogenic brain abcess without therapeutic drainage: A case of central vertigo

Otogenic brain abscess is a severe infection that must be treated as early as possible. Rare cases with a high mortality rate can be reduced by recognizing the red flags of a brain abscess, such as headaches, mental status changes, fever, and focal neurological deficits. Those could be supported by modern diagnostic management and adequate antibiotic therapy that was able to penetrate the central nervous system and abscesses. We report a case of a cerebellar abscess of the 49-year-old man with the chief complaint of vertigo. It was accompanied by chronic progressive headache, fever, bidirectional nystagmus, abnormal Romberg test, and abnormal cerebellar signs. Magnetic resonance imaging (MRI) of the head with contrast showed a right cerebellar abscess with an infectious source of otitis media and mastoiditis. The MRI evaluation showed improvement after admistered metronidazole 500 mg every 6 hours (week 22) and cefixime 200 mg every 12 hours (week 13). Long-term antibiotic treatment can be an alternative if surgery cannot be performed. However, surgery is still considered if there is no good clinical response during medical therapy.

Robot-assisted stereotactic multiple brain abscesses' puncture: technical case report

We report a case of multiple brain abscesses' puncture, employing the ROSA™ Brain surgical robot (Zimmer Biomet) and the O-arm® O2 Imaging System (Medtronic). A 51-year-old man was diagnosed with multiple supratentorial ring enhancing cystic lesions consistent with brain abscesses. A neurological deterioration occurred despite broad spectrum antibiotic therapy, due to mass effect of the abscesses. Stereotactic aspiration was performed using the described technique, allowing a single stage puncture of the cerebral lesions. In this case, the robot-assisted and image-guided procedure permitted an accurate, quick, and efficient targeting of the multiple abscesses for drainage.

Orbital abscess: 20 years' experience at a tertiary eye care center

PURPOSE

To study the clinical, microbiological profile and management outcomes of orbital abscess at a tertiary care center in South India.

MATERIAL AND METHOD

In a retrospective interventional case series, we reviewed all patients diagnosed with orbital cellulitis from 2000-2020. The data analyzed included demographic profile, clinical and radiological features, microbiological profile, and management outcome.

RESULTS

A total of 921 cases of orbital and periorbital infections were reviewed. Seventy-two cases were diagnosed as orbital cellulitis. Thirty-four cases (47.22%) had radiological evidence of orbital abscess. The median age was 20.63 years. Three patients (8.82%) were neonates. A male preponderance was noted (23, 67.65%). Sinusitis (10, 29.41%) and diabetes (5, 14.7%), were the most common predisposing factors. Optic neuropathy was seen in 15 (44.11%) patients, cavernous sinus thrombosis in two patients (5.88%), and septicemia in one patient (2.94%) Multiple orbital abscesses were noted in 7 (20.59%) cases. All patients underwent surgical drainage. Methicillin-sensitive Staphylococcus aureus was the most common organism isolated in 14 patients (41.18%). Vision improvement or stabilization was seen in all except 3 (8.82%).

CONCLUSION

Orbital abscess is a potential sight-threatening orbital infection. The infective process can spread and ascend up to involve cavernous sinus thereby becoming life-threatening. A timely diagnosis and intervention can halt the disease process and help restore vision in many cases.

Spontaneous Propionibacterium Acnes abscess with intraventricular rupture in an immunocompetent adult without prior neurosurgical intervention

Previously viewed as a culture contaminant, Propionibacterium Acnes can cause infection following neurosurgical intervention. Its role in brain abscess in the immunocompetent, surgically naïve population has been infrequently reported. Herein, we describe an immunocompetent 55-year-old man with no risk factors found to have a thalamic abscess with intraventricular rupture.

Post-herpetic encephalitis cerebral abscess: Viral reactivation or latency site within central nervous system?

Herpetic encephalitis results from central nervous system invasion by herpes simplex virus. We report the case of a man who developed a cerebral abscess fifteen months after initial Herpetic encephalitis. Retrospectively, antiviral should not have been associated with antibiotics during abscess episode, as transcriptomic analysis reported no viral reactivation.

Overview of Brain-to-Gut Axis Exposed to Chronic CNS Bacterial Infection(s) and a Predictive Urinary Metabolic Profile of a Brain Infected by Mycobacterium tuberculosis

A new paradigm in neuroscience has recently emerged - the brain-gut axis (BGA). The contemporary focus in this paradigm has been gut → brain ("bottom-up"), in which the gut-microbiome, and its perturbations, affects one's psychological state-of-mind and behavior, and is pivotal in neurodegenerative disorders. The emerging brain → gut ("top-down") concept, the subject of this review, proposes that dysfunctional brain health can alter the gut-microbiome. Feedback of this alternative bidirectional highway subsequently aggravates the neurological pathology. This paradigm shift, however, focuses upon non-communicable neurological diseases (progressive neuroinflammation). What of infectious diseases, in which pathogenic bacteria penetrate the blood-brain barrier and interact with the brain, and what is this effect on the BGA in bacterial infection(s) that cause chronic neuroinflammation? Persistent immune activity in the CNS due to chronic neuroinflammation can lead to irreversible neurodegeneration and neuronal death. The properties of cerebrospinal fluid (CSF), such as immunological markers, are used to diagnose brain disorders. But what of metabolic markers for such purposes? If a BGA exists, then chronic CNS bacterial infection(s) should theoretically be reflected in the urine. The premise here is that chronic CNS bacterial infection(s) will affect the gut-microbiome and that perturbed metabolism in both the CNS and gut will release metabolites into the blood that are filtered (kidneys) and excreted in the urine. Here we assess the literature on the effects of chronic neuroinflammatory diseases on the gut-microbiome caused by bacterial infection(s) of the CNS, in the context of information attained via metabolomics-based studies of urine. Furthermore, we take a severe chronic neuroinflammatory infectious disease - tuberculous meningitis (TBM), caused by Mycobacterium tuberculosis, and examine three previously validated CSF immunological biomarkers - vascular endothelial growth factor, interferon-gamma and myeloperoxidase - in terms of the expected changes in normal brain metabolism. We then model the downstream metabolic effects expected, predicting pivotal altered metabolic pathways that would be reflected in the urinary profiles of TBM subjects. Our cascading metabolic model should be adjustable to account for other types of CNS bacterial infection(s) associated with chronic neuroinflammation, typically prevalent, and difficult to distinguish from TBM, in the resource-constrained settings of poor communities.