Peritumoral Citrobacter koseri Abscess Associated with Parasagittal Meningioma

Meningioma-associated abscess: an unusual case report and review of the literature

Central nervous system (CNS) infection and neoplasm occur most often independently. Their concomitant presentation has been noted across different CNS tumours but is considered a rare entity. The phenomenon is mostly seen in relation to direct seeding of infection via frontal air sinuses. Here, we present an unusual case of an occipital meningioma associated with intraparenchymal paratumoural abscess formation. It is also the second documented to culture methicillin-susceptible Staphylococcus aureus. We then review and surmise the relevant literature of meningioma-associated abscess. We discuss the clinical presentations, aetiology, suspected pathogenesis, management and outcomes reported.

Concomitant parasagittal meningioma and adjacent intracranial abscess of occult etiology

INTRODUCTION

Abscesses associated with tumors are a rare entity. Imaging to differentiate abscess from other entities is often non-diagnostic, and often the source of infection is unknown. We present an unusual case of peritumoral abscess infected with both gram-negative and gram-positive bacteria.

METHODS

A 70-year-old, previously healthy male presented with a 1-day history of right-sided facial weakness sparing the forehead, as well as concomitant right upper and lower extremity numbness. A homogenously enhancing mass with adjacent rim-enhancing lesion with diffusion restricting cavity seen on magnetic resonance imaging (MRI) raised the possibility of abscess.

RESULTS

Separate biopsy specimens of both the tumor and adjacent fluid collection during drainage of the collection confirmed World Health Organization (WHO) grade I meningioma and bacterial abscess containing Streptococcus constellatus, Fusobacterium species, Prevotella dentalis, and Parvimonas micra. The histologic diagnosis therefore confirmed the preoperative radiologic findings of two different but associated lesions. Investigations to determine a definitive source of infection were inconclusive, including urinalysis, blood cultures, respiratory cultures, endoscopy, and an orthopantomogram.

CONCLUSIONS

Gram-negative and gram-positive bacteria can both be culprits in the formation of peritumoral abscess. Although the source of infection is unconfirmed, the presence of oropharyngeal flora in the abscess suggests a subclinical odontogenic infection with hematogenous spread to the tumor and adjacent brain.

Abscess within a Glioblastoma: Mimicking a Matryoshka Doll

BACKGROUND

Abscess coexisting within a brain tumor is rare. Case reports in the literature primarily consist of sellar pathology and parenchymal lesions, including meningioma, glioma, and metastases. We report a case of glioblastoma with an intratumoral abscess in a middle-aged patient with no prior invasive procedure or systemic focus of infection.

CASE DESCRIPTION

A 45-year-old woman presented with new-onset generalized seizures and rapidly progressive left hemiparesis. Imaging showed a right frontal necrotic lesion with a peripherally enhancing wall and solid component posteriorly. There was no diffusion restriction within the lesion. She was afebrile, and there was no systemic focus of infection. With provisional diagnosis of malignant glioma, she underwent surgical resection of the lesion. A differential diagnosis of abscess was considered preoperatively because of the rapid increase in size of the lesion. At surgery, there was a pus-filled cavity with a few areas of grayish, soft, flimsy wall and thrombosed veins. This raised a strong suspicion of a coexisting abscess within a malignant glioma, which was confirmed by histopathologic and microbiologic examination.

CONCLUSIONS

It is important for neurosurgeons to be aware of this rare entity. The treatment protocol remains controversial and is primarily guided by expert opinion. It is important to aggressively treat the patient with antibiotics followed by adjuvant therapy for malignancy. The timing and administration of adjuvant therapy are unclear. We suggest a delay of chemotherapy until at least 4 weeks of therapy with sensitive antibiotics.

Unusual cranial infection caused by Citrobacter Koseri

A 60-year-old female had a frontal bone intraosseous meningioma resected 10 years previously. On follow up CT head, an enlarging intraosseous frontal bone lesion was noted. This was thought to be a recurrent frontal meningioma. Intraooperatively, she was found to have an abscess deep to the cranioplasty.

Brain abscess caused by Citrobacter koseri infection in an adult

Citrobacter koseri is a gram-negative bacillus that causes mostly meningitis and brain abscesses in neonates and infants. However, brain abscess caused by Citrobacter koseri infection in an adult is extremely rare, and only 2 cases have been described. Here, we reported a 73-year-old male presenting with a 3-week headache. A history of diabetes mellitus was noted. The images revealed a brain abscess in the left frontal lobe and pus culture confirmed the growth of Citrobacter koseri. The clinical symptoms improved completely postoperatively.

Abscess formation within a cerebellar metastasis: Case report and literature review

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We experienced a patient with a brain abscess within a cerebellar metastasis.

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A brain abscess within a brain neoplasm is a small entity, and only five cases harboring an abscess within a metastatic brain tumor have been reported to date.

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Surgical procedures for brain abscesses and brain tumors are completely different; however, even today, it is difficult to differentiate a brain abscess from a necrotic brain tumor in advance.

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Differentiation between the two is important due to different methods of management; preoperative assumption of the possible coexistence of both types of lesions could lead to a good outcome when we encounter a lesion which has both the imaging characteristics.

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The preferred treatment of a case with both an abscess and a brain metastasis is complete surgical removal of the tumor and targeted antibiotic therapy for the abscess. The present case highlights the importance of considering coexisting diseases prior to surgery.

Introduction

The managements of brain abscesses and brain tumors including brain metastases differ greatly, especially in terms of surgical procedures. Therefore, differentiating between the two is essential for assuring optimal treatment. However, on rare occasion, these two lesions coexist. Only five cases with both a brain tumor and an abscess have thus, far been reported. We experienced a patient with a brain abscess within a cerebellar metastasis.

Case presentation

A middle-aged man receiving treatment for bile duct cancer presented with headache and nausea. Computed tomography (CT) and magnetic resonance (MR) imaging revealed two lesions, one in each cerebellar hemisphere. Although these lesions appeared to be brain metastases, the right lesion showed high intensity on diffusion-weighted images (DWI), and magnetic resonance spectroscopy (MRS) findings suggested an abscess. Surgical puncture of the lesion identified it as a brain abscess histologically, and we thus, administered antibiotics. However, since the lesion grew, we performed a second surgery for removal, which histopathologically the lesion to be a well-differentiated adenocarcinoma. The final diagnosis was an abscess within a cerebellar metastasis.

Discussion/conclusion

Modern diagnostic tools such as DWI and MRS are reportedly reliable for differentiating brain tumors from brain abscesses, though they are not specific in cases with both lesions. The present case highlights the importance of considering coexisting diseases prior to surgery when we encounter a lesion which has the imaging characteristics of both a tumor and an abscess. The patient may have a better outcome if, preoperatively, surgeons take into consideration the possibility of the coexistence of a brain tumor and a brain abscess.

Abscess caused by Citrobacter koseri infection: three case reports and a literature review

In this report, we present 3 cases of abscess caused by Citrobacter koseri. All infected patients recovered after initial empirical antibiotic treatment and percutaneous drainage of the abscess. We reviewed the literature and found 9 adult cases of C. koseri abscess. Most of these patients recovered after timely antibiotic treatment and drainage.

Glioblastoma multiforme with an abscess: case report and literature review

An intratumoral or peritumoral microbial intracranial abscess is an infrequent diagnosis. The development of this complication may not be preceded by apparent local or general infection in all cases. To identify this diagnosis by radiological (MRI) or laboratory investigations is very intricate. Nevertheless, the recommended life-saving strategy is early surgery with resolution of both the tumor and infection. If subsequent oncological treatment is required, it has to be adjusted for prevention of re-inflammation. The described patient suffered from an intracranial abscess superimposed on a Glioblastoma Multiforme. The confirmed etiological agent was Staphylococcus aureus. The suspected route of microbial migration and colonization in this tumor was bacteremia via agents from thrombophlebitis. The patient is in a good condition following surgery, antimicrobial treatment, and radiotherapy.

Low-grade astrocytoma associated with abscess formation: case report and literature review

A rare case of low-grade astrocytoma associated with abscess formation occurred in a 52-year-old man presenting with Broca's aphasia. He underwent craniotomy and tumor removal under the impression of brain tumor with necrotic cystic change. Abscess accumulation within the intra-axial tumor was found intraoperatively. Literature related to brain abscess with brain tumor is reviewed, with an emphasis on abscesses with astrocytoma. We discuss the common brain tumors that are associated with abscess, pathogens that coexist with brain tumor, and the pathogeneses of coexisting brain abscess and tumor. It is very important to know how to differentiate between and diagnose a brain abscess and tumor, or brain abscess with tumor, preoperatively from clinical presentation and through the use of computed tomography, conventional magnetic resonance imaging, diffusion-weighted imaging or magnetic resonance spectroscopy.