Klebsiella brain abscess in adults

Klebsiella pneumoniae invasive syndrome with pneumocephalus and extensive cerebral infarction: Case report

A 54-year-old female with diabetes was admitted with fever and altered consciousness. Laboratory tests revealed venous blood glucose level of 43.79 mmol/L. Computed tomography (CT) scans of the head, chest, and abdomen showed a right-sided pneumothorax, consolidation, and atelectasis in the right lung; a large heterogeneous density lesion with fluid and gas-fluid levels in the liver; and scattered gas shadows in both kidneys, respectively. Blood and puncture fluid cultures indicated infection with Klebsiella pneumoniae. Based on the susceptibility profiles of the isolates, imipenem was administered intravenously to treat the infection. On the third day of hospitalization, the patient's condition worsened, with head CT showing an extensive cerebral infarction and multiple gas accumulations in the right cerebral hemisphere, as well as a large-area cerebral infarction in the left parietal and occipital lobes. Ultimately, the patient died of multiple organ dysfunction on the fourth day after initial presentation. Although the Klebsiella pneumoniae isolates from the patient showed sensitivity to imipenem, this antibiotic shows poor entry into the central nervous system. The death of the patient indicates that the selection of antibiotics that can cross the blood-brain barrier may be crucial in the outcome of this type of case. Therefore, antibiotics that can penetrate the blood-brain barrier should be selected as soon as possible, and empirical treatment must be initiated immediately after clinical suspicion of invasive Klebsiella pneumoniae, even if the diagnosis has not been determined.

Surgical aspiration versus excision for intraparenchymal abscess: a systematic review and Meta-analysis

Brain abscesses are associated with considerable morbidity and mortality, requiring timely intervention to achieve favourable outcomes. With the advent of high-resolution computed tomography (CT) imaging, mortality following both aspiration and excision of brain abscesses has improved markedly. As a result, there has been a marked shift in neurosurgical practice with aspiration eclipsing excision as the favoured first-line modality for most abscesses. However, this trend lacks sufficient supporting evidence, and this systematic review and meta-analysis seeks to compare aspiration and excision in the treatment of brain abscess. Twenty-seven studies were included in the systematic review, and seven comparative papers in meta-analysis. Aspiration was the chosen technique for 67.5% of patients. Baseline characteristics from the studies included only in the systematic review demonstrated that abscesses treated by aspiration were typically larger and in a deeper location than those excised. In the meta-analysis, we initially found no significant difference in mortality, re-operation rate, or functional outcome between the two treatment modalities. However, sensitivity analysis revealed that excision results in lower re-operation rate. On average, the included studies were of poor quality with average Methodological Index for Non-Randomized Studies (MINORS) scores of 10.3/16 and 14.43/24 for non-comparative and comparative papers respectively. Our study demonstrates that excision may offer improved re-operation rate as compared to aspiration for those abscesses where there is no prior clinical indication for either modality. However, no differences were found with respect to mortality or functional outcome. Evidence from the literature was deemed low quality, emphasizing the need for further investigation in this field, specifically in the form of large, well-controlled, comparative trials.

Hydrocephalus as a delayed presentation of Klebsiella pneumoniae ventriculitis: a case report

A new hypervirulent variant of Klebsiella pneumoniae has emerged. In contrast to classic Klebsiella pneumoniae, it can cause serious and life-threatening infection. It has the ability of spreading from the gastrointestinal and genitourinary systems in non immunocompromised patients to the liver, lung, brain and the eye. High morbidity and mortality have been reported especially if there is a CNS involvement. A prompt search for a distant infective metastasis and its early treatment can improve the outcome. This is a report of a patient presenting with delayed obstructive hydrocephalus secondary to an obstructive urosepsis.

Klebsiella pneumoniae-related brain abscess and meningitis in adults: Case report

INTRODUCTION

Klebsiella pneumoniae is once thought to be a less common cause of brain abscess in adults and is mainly hospital-acquired. Community-acquired CNS infection (brain abscess and meningitis) caused by K pneumoniae without other metastatic septic abscesses is exceedingly rare. Therefore, we present a rare adult patient with invasive cerebral abscess and meningitis without other invasive abscesses related to K pneumoniae.

PATIENT CONCERNS

A 64-year-old woman experienced a sudden onset of severe continuous headache accompanied by intermittent nausea, vomiting, and fever. Meanwhile, she experienced tinnitus and had a feeling of swelling in the right ear.

DIAGNOSIS

Cranial magnetic resonance imaging revealed abnormal hyperintensity signals in the left head of the caudate nucleus. The next generation sequencing of cerebral spinal fluid showed infection with K pneumoniae. The patient was diagnosed with K pneumoniae-related brain abscesses and meningitis.

INTERVENTIONS

Antibacterial treatment was carried out for 2 months.

OUTCOMES

The patient recovered well.

CONCLUSION

Despite the progress of modern neurosurgical techniques, new antibiotics, and modern imaging techniques, brain abscesses are still a potentially fatal infection. Streptococci are common organisms that result in brain abscesses. Nevertheless, Klebsiella species, once thought to be a less common cause of brain abscess in adults, has become an increasingly important cause of brain abscess, especially in Asia.

Klebsiella oxytoca Complex: Update on Taxonomy, Antimicrobial Resistance, and Virulence

Klebsiella oxytoca is actually a complex of nine species-Klebsiella grimontii, Klebsiella huaxiensis, Klebsiella michiganensis, K. oxytoca, Klebsiella pasteurii, Klebsiella spallanzanii, and three unnamed novel species. Phenotypic tests can assign isolates to the complex, but precise species identification requires genome-based analysis. The K. oxytoca complex is a human commensal but also an opportunistic pathogen causing various infections, such as antibiotic-associated hemorrhagic colitis (AAHC), urinary tract infection, and bacteremia, and has caused outbreaks. Production of the cytotoxins tilivalline and tilimycin lead to AAHC, while many virulence factors seen in Klebsiella pneumoniae, such as capsular polysaccharides and fimbriae, have been found in the complex; however, their association with pathogenicity remains unclear. Among the 5,724 K. oxytoca clinical isolates in the SENTRY surveillance system, the rates of nonsusceptibility to carbapenems, ceftriaxone, ciprofloxacin, colistin, and tigecycline were 1.8%, 12.5%, 7.1%, 0.8%, and 0.1%, respectively. Resistance to carbapenems is increasing alarmingly. In addition to the intrinsic bla_OXY, many genes encoding β-lactamases with varying spectra of hydrolysis, including extended-spectrum β-lactamases, such as a few CTX-M variants and several TEM and SHV variants, have been found. bla_KPC-2 is the most common carbapenemase gene found in the complex and is mainly seen on IncN or IncF plasmids. Due to the ability to acquire antimicrobial resistance and the carriage of multiple virulence genes, the K. oxytoca complex has the potential to become a major threat to human health.

Klebsiella brain abscess in an immunocompetent patient: a case report

Background

Klebsiella pneumoniae brain abscesses are a rare entity and typically present in immunocompromised patients. We present a case of an overall healthy patient who developed a Klebsiella pneumoniae brain abscess in the absence of liver pathology.

Case presentation

A 46-year-old Vietnamese man with past medical history significant for hypertension presented to the hospital with acute on chronic worsening of altered mental status, personality changes, and gait dysfunction. Initial vitals revealed temperature of 37.1 °C, heart rate 87 beats/minute, blood pressure 150/87 mmHg, respiratory rate 18/minute, and oxygen saturation 99% on room air. Physical exam was notable for altered mental status, Glasgow Coma Scale (GCS) score of 14, and right lower facial droop. Cardiopulmonary exam was within normal limits. Head computed tomography (CT) showed a left frontotemporal mass, with subsequent brain magnetic resonance imaging (MRI) revealing a ring-enhancing lesion concerning for a brain abscess. The abscess was urgently drained; however, there was intraoperative spillage into the ventricles. Intraoperative cultures grew Klebsiella pneumoniae, and the patient was maintained on appropriate antibiotics. He developed worsening mental status, septic shock, and cerebral edema requiring decompressive left hemicraniectomy. Computed tomography of the abdomen and pelvis revealed no hepatic lesions. The patient did not improve, and the family elected for comfort measures.

Conclusion

High mortality is associated with Klebsiella pneumoniae (as opposed to Klebsiella oxytoca) brain abscesses, especially in the setting of intraventricular spread. This case illustrates the need for early detection, and an aggressive medical and surgical treatment approach is required for a potential favorable outcome.

Gas-containing brain abscess: etiology, clinical characteristics, and outcome

Gas-containing brain abscess remains a life-threatening disease that requires immediate diagnostic and therapeutic intervention. The aim of this study is to report on a series of gas-containing brain abscess and discuss its pathological mechanism and therapeutic consideration. This study included 11 patients with gas-containing brain abscess at Kaohsiung Chang Gung Memorial Hospital, Kaohsiung, Taiwan during a 27-year period. The predisposing factors to infection included hematogenous spread in five patients, contiguous infection in one patient, and abnormal fistulous communication due to head injury in four patients. In one patient, the predisposing factor might be contiguous infection from frontal sinusitis or abnormal fistulous communication due to previous sinus surgery. Klebsiella pneumoniae was the most common causative pathogen that was isolated from the gas-containing abscess not related to skull base defect. Among these 11 patients, six underwent excision and five accepted aspiration for the surgical treatment of abscess. In the five patients who underwent aspiration, two required repeated craniotomy to excise the recurrent abscess and repair the abnormal fistulous communication through the skull base. When encountered with a gas-containing abscess in patients with an impaired host defense mechanism, K. pneumoniae infection should be suspected, and further attention should be paid to discovering if other metastatic septic abscesses exist. For patients with a history of basilar skull fracture or surgery involving the skull base, craniotomy is indicated to excise the abscess and repair the potential fistulous communication through the cranium. Aspiration may be a reasonable alternative to treat deep-seated lesions, lesions in an eloquent area, patients with severe concomitant medical disease, or patients without a history of basilar skull fracture or surgery involving the skull base. Prompt diagnosis, appropriate antibiotic use, and meticulous surgical treatment are the only way to obtain a favorable outcome.

Magnetic resonance features of pyogenic brain abscesses and differential diagnosis using morphological and functional imaging studies: a pictorial essay

The aim of this paper is to illustrate the potential of magnetic resonance imaging (MRI) in diagnosis, differential diagnosis, treatment planning and evaluation of therapy effectiveness of pyogenic brain abscesses, through the use of morphological (or conventional) and functional (or advanced) sequences. Conventional MRI study is useful for the identification of lesions, to determine the location and morphology and allows a correct hypothesis of nature in the most typical cases. However, the differential diagnosis from other brain lesions, such as non-pyogenic abscesses or necrotic tumors (high-grade gliomas and metastases) is often only possible through the use of functional sequences, as the measurement of diffusion with apparent diffusion coefficient (DWI-ADC), proton magnetic resonance spectroscopy ((1)H-MRS) and perfusion weighted imaging (PWI), which complement the morphological sequences and provide essential information on structural, metabolic and hemodynamic characteristics allowing greater neuroradiological confidence. Modern diagnostic MRI of pyogenic brain abscesses cannot be separated from knowledge, integration and proper use of the morphological and functional sequences.

A Case of Ventriculitis Associated with Renal Abscess Caused by Serotype K1 Klebsiella pneumoniae

Recently, serotype K1 Klebsiella pneumoniae has been a major agent of an invasive syndrome characterized by liver abscess and its metastatic infection. Extrahepatic infection and its characteristics in patients with renal abscess caused by K. pneumoniae are poorly understood, and few cases of central nervous system infection have been reported. This is a report of 80-year-old woman with uncontrolled type 2 diabetes mellitus with renal abscess caused by serotype K1 K. pneumoniae, complicated with ventriculitis despite of appropriate use of antibiotics. Physicians need to be aware of possibility of metastatic infection in patients with serotype K1 K. pneumoniae infection, if they develop neurologic symptom and focus of infection is still present.

The experiences of non-operative treatment in patients with bacterial brain abscess

Although treatment of brain abscess requires a combination of antimicrobials and surgical intervention for the infected foci, nonsurgical, empirical treatment is possible and efficient in selected groups of patients. A total of 31 patients were enrolled in this 22-year retrospective study. We describe our therapeutic experiences and attempt to analyze the risk factors that were predictive of therapeutic outcomes. Multiple logistic regression was used to evaluate the relationships between baseline clinical factors and therapeutic outcome during the study period. Of these 31 patients, 25 had community-acquired infections, whereas the other six had nosocomially-acquired infections. Thirteen cases (42%) had a single brain abscess and the other 18 cases (58%) had multiple brain abscesses. Furthermore, the association of bacterial meningitis and brain abscess was found in 81% (25/31) of cases. The overall case fatality rate was 48% (15/31). Significant risk factors for poor outcomes included Glasgow coma scale (GCS) at presentation, presence of septic shock and neck stiffness. In addition, each reduction of one point on the GCS increased the poor outcome rate by 28%. The findings of the study demonstrate that both a higher mortality rate (48%) and worse outcomes were found in this select group of patients. Among the significant prognostic factors, a lower mean GCS at presentation was a major determinant of poor outcome.

Gas-forming brain abscess caused by Klebsiella pneumoniae

Gas forming brain abscess is a rare disease caused by Klebsiella pneumoniae occurring in patients with impaired host defense mechanism such as diabetes mellitus or liver cirrhosis. A 59-year-old man with 2-year history of diabetes mellitus and 20-year history of liver cirrhosis presented to the hospital with headache. On the day after admission, severe headache was developed and he deteriorated rapidly. Brain CT showed a non-enhanced mass including multiple air density as well as surrounding edema seen in the right occipital lobe, and isodensity air-fluid level seen in the right lateral ventricle. Despite emergent ventricular drainage and intraventricular and intravenous administration of antibiotics, his condition progressively worsened to sepsis and to death after 5 days. Bacterial culture of blood and ventricular fluids disclosed a Gram (-) rod, Klebsiella pneumoniae. In this report we review the pathogenic mechanism and its management.

Unusual complications and presentations of intracranial abscess: experience of a single institution

BACKGROUND

Complicating events and unusual presentations associated with intracranial abscess are rare but potentially fatal conditions. This study was undertaken to shed light on the unusual complications and presentations of intracranial abscess treated at a single institution.

METHODS

We retrospectively reviewed 116 cases of intracranial abscesses that were treated at our institution over the last 10 years and identified 11 (9.4%) cases with unusual complications.

RESULTS

These complications consisted of (1) rupture within the abscess, (2) hemorrhage into the abscess, (3) hemispheric infarction due to ICA thrombosis, (4) acute visual loss due to pituitary abscess, (5) acute neurologic deterioration due to rapid gas formation within the abscess, (6) acute hydrocephalus, (7) trigeminal neuralgia, (8) fungal abscess developing secondary to intracranial extension of a temporal bone tumor, (9) Cryptococcus abscess with different morphology, (10) pontine infarction, and (11) sigmoid sinus thrombosis. Sinusitis accompanied 8 (72.7%) of the cases, and there were 5 (45.4%) mortalities. Culture results were unyielding in 4 patients, whereas Streptococcus species were identified in 4 and fungi in the rest.

CONCLUSION

Intracranial abscesses and their complications still continue to be challenging entities in the neurosurgical practice. Our experience may provide an informational source for those who are taking care of patients with intracranial abscess.

Clinical features and predictive factors of intraventricular rupture in patients who have bacterial brain abscesses

BACKGROUND

Intraventricular rupture of brain abscesses (IVRBA) remains a catastrophic and fatal complication of bacterial brain abscess (BBA). However, no information has been reported about the risk factors that are predictive of intraventricular rupture.

METHODS

This study was undertaken to determine the potential risk factors that are predictive of intraventricular ruptures in patients with BBA but without intraventricular rupture when arriving at the hospital. A comparison is also made between patients who already have IVRBA at the time of admission (initial IVRBA) and those who have the episode during hospitalisation (subsequent IVRBA).

RESULTS

62 patients, including 45 who had initial IVRBA and 17 who had subsequent IVRBA, were examined. Stepwise logistic regression analysis showed that the adjusted risk of intraventricular rupture during hospitalisation for patients with multiloculated brain abscesses had an odds ratio (OR) of 4.2 (95% confidence interval (CI) 1.24 to 14.3; p = 0.02) compared with those without multiloculated brain abscesses (referent); a reduction of 1 mm in the distance between the ventricle and brain abscesses would increase the rupture rate by 10% (p = 0.006, OR 0.9, 95% CI 0.83 to 0.97).

CONCLUSION

This study shows that if the abscess is deep seated, multiloculated and close to the ventricle wall, a reduction of 1 mm in the distance between the ventricle and brain abscesses will increase the rupture rate by 10%. Despite aggressive medical and surgical management shown in this series, many patients continue to progress poorly.

Brain abscess caused by aerobic Gram-negative bacilli: clinical features and therapeutic outcomes

Thirty-three patients (24 males and nine females) with brain abscesses resulting from infection by aerobic Gram-negative bacilli were identified at Kaohsiung Chang Gung Memorial Hospital over a period of 14 years. Of these, 23 cases developed spontaneously, with the remaining ten postneurosurgery. The organisms most frequently involved were Klebsiella (K.) pneumoniae, Pseudomonas aeruginosa, Escherichia coli and Proteus species and included some rare pathogens, such as Salmonella and Enterobacter species, K. oxytoca, Vibrio and Morganella morganii. Apart from one exception, the locations of the abscess were supratentorial. Twenty-four patients presented with a single abscess, while nine revealed multiple abscesses, with 26 treated surgically and seven with antibiotics exclusively. In total, seven patients died, representing an overall mortality rate of 21%. This study demonstrates that brain abscesses associated with neurosurgical procedures are not rare, accounting for 30% of cases in this study, with K. pneumoniae, Proteus and Enterobacter species the most prevalent of the revealed pathogens. Further, Proteus species were the most prevalent pathogens demonstrated for cases of both otogenic and polymicrobial infections. If brain abscesses are diagnosed for diabetic patients or have a gas-forming appearance, a diagnosis of K. pneumoniae infection should be considered, with particular attention paid to detection of other metastatic septic abscesses. In light of the high mortality rate, early treatment is essential to maximize the chances of survival.