Brain abscess in a neonate: an unusual presentation

Neonatal Brain Abscess with Serratia marcescens after Intrauterine Infection: A Case Report

Brain abscesses are a possible complication of bacterial sepsis or central nervous system infection but are uncommon in the neonatal period. Gram-negative organisms often cause them, but Serratia marcescens is an unusual cause of sepsis and meningitis in this age group. This pathogen is opportunistic and frequently responsible for nosocomial infections. Despite the existing antibiotics and modern radiological tools, mortality and morbidity remain significant in this group of patients. We report an unusual unilocular brain abscess in a preterm neonate caused by Serratia marcescens. The infection had an intrauterine onset. The pregnancy was achieved through assisted human reproduction techniques. It was a high-risk pregnancy, with pregnancy-induced hypertension, imminent abortion, and required prolonged hospitalization of the pregnant woman with multiple vaginal examinations. The infant was treated with multiple antibiotic cures and percutaneous drainage of the brain abscess associated with local antibiotic treatment. Despite treatment, evolution was unfavorable, complicated by fungal sepsis (Candida parapsilosis) and multiple organ dysfunction syndrome.

Unusual presentation of brain abscess in a 23-month-old infant

BACKGROUD

Pediatric brain abscesses usually occur as a consequence of predisposing conditions, such as ENT (ear, nose, and throat) infection and physical damage. But there are still a number of cryptogenic infection cases.

METHODS

We present an unusual cryptogenic infection case of multiple and multiloculated brain abscess in an infant, which was in the absence of ENT infection, meningitis, trauma, prior surgery, cyanotic heart disease, or immune defect. The child has no specific symptoms but keeping apathic and days of diarrhea. Deduced from clinical presentation and this case's DWI-MRI features, the onset of infection is hematogenous route, and the diarrhea could be the possible inducement. The child was successfully treated by surgical excision of big lesions and an 8-week total course of intravenous antibiotics. At the end of the 1-year follow-up period, the infant is well at both of physical and mental health.

CONCLUSION

The interest of this case is the silent clinical presentation and the possibly rare precipitating factor. To a certain extent, the variation trend of blood C-reactive protein level could predict the clinical effect of antibiotics in brain abscess case.

Brain abscess in children, a two-centre audit: outcomes and controversies

OBJECTIVE

The aim of this study was to better characterise clinical presentation, management and outcome in infants and children with brain abscess.

METHODS

The authors conducted a retrospective, multicentre study in two national reference centres over a 25-year period (1992-2017). During this period, 116 children and 28 infants (age <1 year) with brain abscess were treated.

RESULTS

The median age at diagnosis was 101.5 (range: 13-213) months in children and 1 (0-11) month in infants. Significant differences were observed between children and infants. The most common predisposing factor was meningitis in infants (64% of cases vs 3% in children), while it was otolaryngology-related infection in children (31% of cases vs 3.6% in infants). Infants presented more frequently with fever and meningism compared with children. 115 patients were treated with aspiration and 11 with excision. Reoperation was required in 29 children vs 1 infant. The overall mortality rate was 4% (3.4% for children, 7.1% for infants). At 3-month follow-up, the outcome was favourable in 86% of children vs in 68% of infants.

CONCLUSION

There is a clear difference between children and infants with brain abscess in terms of predisposing factors, causative organisms and outcome. Despite surgical drainage and directed antibiotic therapy, 25% of patients with brain abscess require reoperation. Mortality is improved compared with historical series; however, long-term morbidity is significant particularly in the infant population.

A retrospective study (2001-2017) of acute and chronic morbidity and mortality associated with Staphylococcus aureus bacteraemia in a tertiary neonatal intensive care unit

BACKGROUND

Staphylococcus aureus bacteraemia (SAB) in NICU patients can cause significant morbidity and mortality.

AIMS

To review early and late neonatal SAB with regard to risk factors, treatment, acute complications and long-term outcomes.

METHODS

A retrospective study of laboratory confirmed SAB over a 16-year period (November 2001-January 2017) in a tertiary neonatal unit in Ireland.

FINDINGS

A total of 74 neonates (MSSA n = 72, MRSA n = 2) were identified; 8.1% (n = 6) early sepsis, 91.8% (n = 68) late sepsis. Low birth weight neonates (born weighing less than 2500 g) 80% (n = 59). Median age to bacteraemia 11 days post-delivery (range = 0-100 days); median onset early sepsis 1.5 days versus late sepsis 12 days. Complications of SAB; cellulitis n = 17, pneumonia n = 12, necrotising enterocolitis n = 7, thromobophlebitis n = 5, skin abscess formation n = 4, osteomyelitis n = 3, endocarditis n = 1. Late SAB mortality 6.4% (n = 3).

CONCLUSIONS

Preterm and low birth weight infants were at highest risk of SAB. Only a small proportion of affected children had long-term clinical sequelae on follow-up. The high rate of recurrence and breakthrough bacteraemia suggests that early implementation of a targeted anti-staphylococcal antimicrobial regimen may be of particular benefit.

Expression of MMP-2 and TIMP-1 in cerebrospinal fluid and the correlation with dynamic changes of serum PCT in neonatal purulent meningitis

Matrix metalloproteinase 2 (MMP-2) and tissue inhibitor of metalloproteinase-1 (TIMP-1) levels in cerebrospinal fluid of pediatric patients with neonatal purulent meningitis were observed to analyze changes in serum procalcitonin (PCT) and the correlation among the three factors (MMP-2, TIMP-1 and PCT). Sixty pediatric patients with neonatal purulent meningitis from April 2015 to December 2016 were enrolled as the purulent meningitis group and 60 pediatric patients with viral encephalitis treated during the same period were enrolled as the viral encephalitis group. Additionally, 60 healthy newborns who underwent physical examinations in our hospital during the same period were enrolled as the control group. The levels of MMP-2 were 136.73±25.42 ng/ml in the purulent meningitis group, 45.32±6.57 ng/ml in the viral encephalitis group and 1.32±0.51 ng/ml in the control group and the differences between the three groups were statistically significant (F=15.052, p<0.05). The levels of TIMP-1 in cerebrospinal fluid were 374.55±36.04 ng/ml in the purulent meningitis group, 176.61±21.06 ng/ml in the viral encephalitis group and 7.72±2.44 ng/ml in the control group. The serum levels of PCT were 14.56±2.21 ng/ml in the purulent meningitis group, 9.04±1.17 ng/ml in the viral encephalitis group and 0.38±0.14 ng/ml in the control group. The level of MMP-2 in cerebrospinal fluid of pediatric patients in the purulent meningitis group was positively correlated with the level of serum PCT (r=0.582, p<0.05); the level of TIMP-1 in cerebrospinal fluid of pediatric patients in the viral encephalitis group was positively correlated with the level of serum PCT (r=0.635, p<0.05). In conclusion, MMP-2 and TIMP-1 were positively correlated with the levels of serum PCT, suggesting that MMP-2, TIMP-1 and PCT were involved in the occurrence and development of neonatal purulent meningitis.

Pediatric brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma: a case report

PURPOSE

We report a rare case of brainstem abscess with hemorrhage mimicking diffuse intrinsic pontine glioma (DIPG).

METHODS

A 7-month-old baby girl presented with lethargy and poor oral feeding. She had the mild fever for 1 month. Brain computed tomography revealed the hypodense lesion in the pons. Brain magnetic resonance images (MRI) showed around 1.4-cm-sized rim-enhanced mass with perilesional edema and internal hemorrhage in the pons. The cerebral blood volume was increased in the rim-enhanced area. The provisional diagnosis was DIPG, but the mass did not show the expansile mass with encasement of the basilar artery on the ventral pons.

RESULTS

The biopsy was done via the floor of the fourth ventricle, and the pathologic findings showed the many inflammatory cells and CD68-immunopositive macrophage which were compatible with abscess. The antibiotics with ceftriaxone and metronidazole were administrated for 11 weeks, and the follow-up MRI showed the slightly small enhanced lesion without central necrotic area. Three years later, follow-up MRI revealed the encephalomalacic change and atrophy of the pons. She had the stable neurologic deficit of left facial palsy and right hemiparesis.

CONCLUSION

The biopsy could be necessary for pontine lesions without typical radiologic findings of DIPG.

Candida tropicalis brain abscess in a neonate: An emerging nosocomial menace

Fungi are a relatively uncommon cause of brain abscess in neonates and early infancy. They are usually associated with predisposing factors like prematurity, low birth weight, use of broad-spectrum antibiotics, and prolonged stay in the intensive care unit. Candida tropicalis (C. tropicalis) is rapidly emerging as a nosocomial threat in the neonatal intensive care settings. This case report describes a neonate with C. tropicalis brain abscess who was diagnosed early and managed aggressively with a favorable outcome. Inadvertent use of intravenous antibiotics can have serious complications such as invasive fungal infection. Correct microbiological diagnosis is the key to successful treatment of deep-seated pyogenic infection. Fungal etiology should always be studied in relevant clinical settings.

Neonatal deep white matter venous infarction and liquefaction: a pseudo-abscess lesion

BACKGROUND

Deep white matter hemorrhagic venous infarction with subsequent cavitation due to necrosis and liquefaction has been described in neonates and may be associated with infection and meningitis. In our experience, the MRI pattern of these lesions is confused with the pattern seen with cerebral abscesses.

OBJECTIVE

The purpose of our study was to characterize the MRI findings of post infarction necrosis and liquefaction after hemorrhagic deep white matter venous infarction in infants and to distinguish these lesions from cerebral abscesses.

MATERIALS AND METHODS

An institutional review board approved a retrospective review of imaging records to identify all patients with cerebral venous infarction at a children's hospital during a 10-year period. Nine infants had deep white matter hemorrhagic venous infarction with white matter fluid signal cavitary lesions. A diagnosis of cerebral abscess was considered in all. The imaging and laboratory findings in these patients are reviewed and compared to descriptions of abscesses found in the literature.

RESULTS

There were six female and three male infants. The mean age at presentation was 20 days (range: 0-90 days), while the corrected age at presentation was less than 30 days for all patients. Seven patients presented with seizures and signs of infection; one infant presented with lethargy and later proved to have protein C deficiency. MRI was performed 0-12 days from presentation in these eight patients. Another patient with known protein C deficiency underwent MRI at 30 days for follow-up of screening US abnormalities. There were a total of 38 deep cerebral white matter fluid signal cavitary lesions: 25 frontal, 9 parietal, 2 temporal, 2 occipital. Larger lesions had dependent debris. All lesions had associated hemorrhage and many lesions had evidence of adjacent small vessel venous thrombosis. Lesions imaged after gadolinium showed peripheral enhancement. Three lesions increased in size on follow-up imaging. Three patients, two with meningitis confirmed via microbiology and one with presumed meningitis by CSF counts, underwent surgical aspiration of a total of six lesions. All specimens were sent for pathology and culture and were negative for microorganisms.

CONCLUSION

Recognizing the MR appearance of cavitary necrosis and liquefaction after deep white matter cerebral venous infarction in neonates can distinguish this entity from cerebral abscess and potentially avoid an unnecessary neurosurgical aspiration procedure.

Diffusion-weighted imaging in neonates

Diffusion-weighted imaging (DWI) has become an important tool in pediatric neuroradiology, helping in the evaluation of the encephalopathic and seizing neonate, and adding conspicuity, specificity, and prognostic value to the conventional magnetic resonance (MR) imaging data. DWI also facilitates understanding the pathophysiology and natural time course of ischemic and nonischemic disorders. When interpreted concurrently with the conventional MR imaging and other advanced MR imaging techniques, such as spectroscopy and arterial spin labeling, DWI can give clues leading to an accurate diagnosis and provide important information about pathophysiology and prognosis of the diseases, as well as guide adequate therapeutic modalities.

Diagnostic and management of pediatric brain stem abscess, a case-based update

PURPOSE

Authors report their experience of a pediatric brain stem abscess with a literature review.

METHODS

A 2.5-year-old girl first displayed bacterial otitis 3 months before admission. Diagnosis of brain stem abscess was delayed, despite plethoric neurological signs. She complained of right hemiparesis, headache, squint, dysphagia, and false way inhalation pneumopathy. Brain magnetic resonance imaging revealed presence of an abscess in the pons, prompting for a microsurgical pus aspiration. Postoperative course was regular with a total neurological recovery. Clinical and radiological screening showed progressive regression of the pontine lesion after 4 months, despite persistence of a mild contrast enhancement. Present case is the 18th pediatric brain stem abscess reported in literature.

RESULTS

Mean age of occurrence is 8.1 ± 4 years (range 0.75-16) without gender predominance. High morbidity is typical and essentially involves motor functions. The most common clinical signs are raised intracranial pressure, motor limbs deficit, and cranial nerve palsies. Fever was found in 10 out of 18 cases (56%). Three patients received conservative medical treatment. Three patients underwent stereotactic aspiration and 12 others underwent microsurgical aspiration or excision. No mortality was reported since the eighties. However, morbidity is still high.

CONCLUSION

High clinical index of suspicion is necessary to improve functional outcome. Stereotactic-guided or microsurgical aspiration are still good therapeutic options. The rarity of pediatric brain stem abscesses and the need of optimal management make this case-based update very peculiar.

Management of brain abscesses in children

Brain abscesses occur infrequently but continue to be problematic for the pediatric neurosurgical community. The incidence of brain abscesses in children has not changed much, although individual reports may show an increase or decrease in the number of reported cases depending on the patient population studied. An increase could be attributed to earlier detection due to advancements in imaging modalities and/or to an increase in the number of children with immunodeficient states caused by AIDS, chemotherapy for malignant lesions, and immunosuppressive therapy for organ transplantation. A decrease in the incidence of brain abscesses could be attributed to practices such as antibiotic treatment for otitis media, sinusitis, and/or prophylactic antimicrobial treatment for congenital heart disease in children. The morbidity and mortality rates associated with brain abscesses have not changed dramatically in the antibiotic and imaging era, and their preferred management can vary among healthcare providers. These lesions have been successfully treated by neurosurgeons. The causes of brain abscesses are highly variable in children, which is also the case in adults, but the predisposing factors in the pediatric population differ in prevalence. Cyanotic congenital heart disease, hematogenous dissemination, contiguous infection, and penetrating traumatic injuries are the most common causes of brain abscesses in children. In this review, the authors discuss the causes and medical and surgical management of brain abscesses in children.