Clinical Profile and Outcome of Brain Abscess in Children from a Tertiary Care Hospital in Eastern Uttar Pradesh.

BACKGROUND AND AIMS: Brain abscess is a serious and dreadful disease presenting at tertiary centre. The objective of this study was to look into the clinical profile, predisposing conditions, microbiology and outcome of children suffering from brain abscess.
METHODS: 30 children up to 18 years with clinical and imaging evidence of brain abscess were taken for study. Patients were stabilized as per unit protocol. Necessary investigations were carried out. Neuroimaging (CT or MRI) was used to confirm the diagnosis. All parameters (clinical, investigation, outcome) were recorded in predesigned performa. Neurosurgery consultation was sought in patients with multiple abscesses, posterior fossa abscesses, abscess with air-fluid level and causing midline shift.
RESULTS: There were 16 males with 13 patients in age group (5-10 years). Mean duration of stay in hospital was 14.8 days. Most common predisposing factor was chronic suppurative otitis media (n-15). Typically, patients presented with fever, headache and seizures. On examination, motor deficits were the most common followed by signs of meningitis. Computerized tomography confirmed the diagnosis in most cases. Temporal lobe (n-11) was the commonest intracranial site for the abscess. Methicillin resistant staphylococcus and proteus mirabilis were the common pathogen isolated from blood and pus. Blood culture positivity rate was 16.7% and pus culture positivity rate was 25%. All cases were managed with intravenous antibiotics and aspiration (n-10) and excision (n-6). There were 5 deaths. There was complete immediate recovery in 13 cases with residual motor deficit in 12 cases.
CONCLUSION: Brain abscess is a rare but serious entity in children. Late diagnosis and improper management leads to poor outcome. Early surgical intervention is helpful. Threshold for diagnosis should be low in children with chronic ear infection and congenital heart diseases. Copyright:

INTRODUCTION

A brain abscess is an intraparenchymal collection of pus in the brain. The incidence of brain abscess among intracranial masses varies from 1-2% in western countries, to about 8% in developing countries.[1] They begin as localised areas of cerebritis in the parenchyma and evolve into pus collection enclosed by a capsule. A multidisciplinary approach is of paramount importance in successful management of brain abscess. It is still a life threatening and fatal entity and often leads to serious disability and even death if misdiagnosed or treated improperly.[2] Modern neurosurgical techniques including stereotactic brain biopsy and aspiration along with better culture techniques, newer generation antibiotics have revolutionized the treatment and outcome of brain abscess. The causative pathogen can vary from Gram positive cocci (Staphylococci, streptococci Peptostreptococci spp), Gram negative bacilli (Klebsiella, Escherichia coli, Salmonella, Bacteroides, Haemophilus, and Proteus spp).[3] Fungal infection, Toxoplasama are found in immunocompromised patients with HIV infection, organ transplantation, chemotherapy and prolonged steroid usage.[4] Clinical presentation of brain abscess depends on multiple factors including location of lesion, pathogenic organism and host immune status. It commonly presents with either a mass lesion with focal neurological deficit or raised intracranial hypertension due to diffuse cerebritis.[5] Management of paediatric brain abscess requires multimodality treatment. Contrast Enhanced CT or Magnetic Resonance Imaging (MRI) usually confirms the diagnosis and management. The use of broad spectrum antibiotics and repeated aspiration and in some cases excision are the current treatment modality. Outcome of paediatric brain abscess primarily depends on GCS (Glasgow Coma Score) at admission and ventricular extension of abscess. Numerous Indian studies have demonstrated mortality ranging from 2.9-44.7%.[678] We performed this study to assess the clinical profile, aetiology, and outcome of paediatric brain abscess in the eastern region of Uttar Pradesh.

METHODS

The present study was conducted in Department of Pediatrics and Department of neurosurgery, Institute of Medical Sciences, Banaras Hindu University, Varanasi. The period of study extended from June 2016 to August 2018. All patients, in age group of 0-18 years, with diagnosis of brain abscess were taken for study. Patients were recruited from Paediatric OPD/emergency/Neurosurgery ward. Relevant history, examination and investigations were done in all patients. All patients received intravenous antibiotics with proper neurosurgical consultation and intensive care support when it was required. Following investigations were performed: Complete blood count, blood culture sensitivity for aerobic, anaerobic and fungal infections, aspirated pus culture sensitivity after burr hole aspiration and craniotomy, Digital X- ray chest, 2D-ECHO (in case of congenital heart disease), serum Immunological profile (IgA, IgG, IgM, IgE). Patients were managed in paediatric ward/intensive care unit depending on their condition. Neurosurgical opinion was taken for aspiration. Selected patients were shifted to Department of Neurosurgery, Trauma Centre, Institute of Medical Sciences, Banaras Hindu University, for surgical management. Patients with following condition required surgical drainage (burr hole aspiration or craniotomy): multiple abscess, abscess causing significant midline shift on neuro-imaging, posterior fossa abscess, suspected fungal abscess and air fluid level in abscess. At time of discharge, all patients underwent detailed neurological examination. Morbidity and mortality were recorded.

Statistical analysis

The clinical, biochemical and hematological parameters, treatment and outcome of all the patients were recorded in standard format. The collected data were analysed using SPSS version 16.0 software. Relevant tables and diagrams were generated from the available data.

RESULTS

Study group consisted of 30 children with 16 males (53.33%). Most common age group affected was 5-10 years group (13 patients) as depicted in Table 1. Fever was the most common clinical presentation (36.7%). It was followed by seizures (26.7%), headache (23.3%) and altered sensorium (10%). Most common clinical finding was motor deficits, seen in 15 (50%) cases. Signs of meningitis were present in 10 (33%) cases. Cranial nerve involvement was found in 5 (16%) cases. Cerebellar signs were seen in only 2 (6%) cases and sensory deficits in 2 (6%) cases [Table 2]. The most common predisposing factor contributing to brain abscess formation was found to be chronic ear discharge, seen in 15 (50%) cases. Congenital cyanotic heart disease was seen in 5 (16%) cases [Table 1]. Mastoiditis was found in 2 (6%) cases. However, no cause was found in 8 (26%) cases. All cases were diagnosed by 128 slice CT or 1.5 T MRI with contrast enhancement. Most common site of brain abscess was Temporal lobe 11 (36%), which was associated with more cases of chronic ear infection [Table 2]; Parietal lobe in 10 (33%), and Frontal lobe- 6 (20%). Cerebellar abscess and intraventricular rupture was seen in 1 (3%) and 2 (6%) cases, respectively.

Table 1

Demographic profile of studied children (n=30)

	Number	Percentage
Gender Male	16	53.3
Age:
<5 yrs	6	20
5-10 yrs	13	43.3
>10 yrs	11	36.7
Predisposing factors
C.S.O.M.	15	50
Congenital Heart disease	5	16.7
Mastoiditis	2	6.7
No cause established	8	26.7

Table 2

Clinical manifestations and Site of involvement in CT scan (n=30)

	Number	Percentage
Clinical symptoms
Fever	11	36.7
Seizures	8	26.7
Headache	7	23.3
Altered sensorium	3	10
Neurological findings
Motor deficits	15	50
Meningeal signs	10	33.3
Cranial nerve palsy	5	16.7
Sensory deficits	2	6.7
Site of abscess in CT Scan
Temporal lobe	11	36.7
Parietal lobe	10	33.3
Frontal lobe	6	20
Cerebellum	1	3.3
Intraventricular rupture	2	6.7

In all cases, blood culture was sent prior to start of antibiotics to identify the causative organism. In selected cases, those who had undergone surgical aspiration, aspirated pus was a sent for culture and sensitivity studies. Blood cultures were positive in 5 patients. Out of which 2 cases showed Methicillin resistant Staph aureus (MRSA) and 2 cultures isolated Proteus mirabilis. Candida sp. was grown in one case [Table 3]. Out of the 30 cases, 16 had undergone aspiration of pus. Pus culture was positive in 4 (25%) cases [Table 3]. Admitted cases were managed based on their clinical status and the need for surgical intervention. Out of the 30 cases, 16 (53%) had undergone aspiration of abscess in Department of Neurosurgery after initial stabilization. Among those children operated, 10 (33%) had undergone burr hole aspiration while in the rest 6 (20%) cases the pus was drained through craniotomy. 14 (43.4%) cases were managed conservatively with intravenous antibiotics and antiepileptic drugs without any surgical intervention. At presentation, broad spectrum antibiotics were used. Most common combination used was vancomycin and cefotaxime or ceftriaxone and metronidazole for at least 14 days, and then followed by oral antibiotics for another 2-4 weeks. Antibiotics were reviewed after culture and sensitivity reports. Two (13.3%) patients required mechanical ventilation and both the children died during the hospital stay. Among those who were operated, one (6.2%) needed mechanical ventilation during reversal of general anaesthesia in post-operative period. However, he completed treatment and survived with residual neurological deficit. Need for mechanical ventilation was associated with poor outcome in all the 3 cases.

Table 3

Microbiological isolates in blood and aspirated pus culture

	Number (%)
Positive blood culture (n=30)	5 (16.7)
MRSA	2 (6.7)
Proteus mirabilis	2 (6.7)
Candida sp.	1 (3.3)
Aspirated pus (n=16)
MRSA	2 (6.7)
Proteus mirabilis	2 (6.7)

Among the 30 cases of brain abscess, 5 (16.6%) died during stay in hospital. Rest of the 25 patients completed treatment and were discharged. Out of these 25 patients, 13 (43.3%) had complete recoveries at the time of discharge while the other 12 (40%) had neurological deficit [Table 4]. Mean duration of hospital stay was 14.8 days.

Table 4

Treatment and outcome of children with brain abscess (n=30)

	Number	Percentage
Treatment
Only intravenous antibiotics	14	46.7
Burr hole aspiration	10	33.3
Craniotomy	6	20
Outcome at discharge
Complete recovery	13	43.3
Residual motor deficit	12	40
Death	5	16.7

DISCUSSION

The present study included a total of 30 cases of brain abscess with most common age group affected was 5-10 years. In our study, males are more affected than females. Males are more exposed to outdoor activities with greater chance of ear infection and predisposing to brain abscess. Also, illiteracy and poor hygiene leads to more chances of chronic ear discharge and brain abscess formation in future.

To make good comparison, we collected the data of Indian cases series, case series from Nepal and Pakistan. The same has been presented in Table 5. Presenting complain of this cohort was fever, headache, seizures and altered sensorium. This type of presentation is previously reported by studies done on paediatric brain abscess.[67891011] Other associated symptoms and signs (like focal deficit, cranial nerve involvement, meningitis, ataxia) could also be presentation in some of cases.[12] Presentation depends on various factors like location and size of abscess, pathogenic virulence and host immune response. Review of literature shows headache, fever and vomiting each occur in 60-70%. Seizures, altered mental status and focal neurologic signs occur in 25-50%.[13] The classic triad of fever, headache and focal deficits occurs in 30% of cases only.[13] Predisposing factors often decide the location and common pathogen of abscess. Frontal Brain abscess often originates from sinus infection or dental infection. Abscess otic in origin is usually temporal and cerebellar.[14] Abscess arising from hematogenous spread are usually in distribution of middle cerebral artery. In the present study, Temporal lobe abscess (n-15) following middle ear infection and mastoiditis was the commonest finding. Temporal lobe abscess following otogenic infection has been found in previous studies.[678] In only one study by Borgohain et al., cerebellum was the commonest site.[9] Cases of CSOM were managed with otolaryngologist by tympanoplasty. Two cases of mastoiditis required radical mastoidectomy along with management of brain abscess. Radical matoidectomy has been described in literature for management of source.[1516] Five cases of Cyanotic heart diseases (Tetrology of Fallot) were referred to department of Cardiothoracic surgery for surgical correction. Most of intracranial brain abscess are solitary rather than multiple. In the present study, all abscess were solitary in nature with intraventricular rupture in 2 cases. This is rare complication with fatal outcome. Both patients died in our series. Intraventricular rupture of abscess has been associated with high mortality.[1718] Poor Glasgow coma scale (GCS) at time presentation has been associated with poor outcome.[11920] Previous studies in India, Nepal and Pakistan have also reported poor GCS as negative prognostic factor in their studies.[681011] Our two cases were of neonatal age group. Both cases were managed by intravenous antibiotics and aspiration. Both survived and discharged. Klebsiella pueumoniae has been identified as most common cause of neonatal brain abscess in developing countries.[21] We isolated Proteus mirabilis as common pathogen in our cases.

Table 5

Comparison of clinical and outcome profile of present study with previous studies

Authors	Place of study	n	Most common age group	Most common predisposing factor	Site	Size	Clinical features
Malik et al.; 1993	Department of Pediatrics, Neurosurgery; Nair hospital Bombay	47	5-15 years (n - 34)	Otogenic (34%) Scalp & face infection (21.3%) Congenital cyanotic heart disease (12.8%)	Supratentorial (75.9%) (Temporal lobe) Cerebellum (13)	Solitary (27) Multiple (20)	Fever (87.2%) Raised ICT (78.7%) Altered sensorium (53.2%) Focal deficit (38.3%)
Hegde et al.; 1986	Department of Neurosurgery; NIMHANS, Banglore	100	11-15 years (n-54)	Otogenic (n-69) Cardiogenic (n- 8) Idiopathic (n-14)	Temporal (n-34) Cerebellelar (n-35) Frontal (n-13) Parietal (n-15)	Solitary (n -98) Multiple (n-2)	Headache & Vomiting (n-80) Focal deficit (n-72) Fever (n-62) Epilepsy (n-32)
Singh et al.; 2001	Department of Neurosurgery; GB Pant hospital, New Delhi	68	7 mon-13 years	Otogenic (n-68)	Temporal (n-58); Cerebellar (n-10)	Solitary (n-66); Multiple (n-2)	Headache (n-36); Vomiting (n-26); fever (n-14); Hemiparesis (n-18) Seizures (n-9); cerebellar signs (n-7); unconciouness (n-3)
Borgohain et al 2015	Department of otorhinolarygology and Head and Neck Surgery; Guwahati, Assam, India	17	5-20 years	Otogenic	Cerebellum (n-16); Temporal (n-1)	Solitary (n-17)	Headache, Nausea, vomiting, ear discharge, seizures,
Atiq et al, 2006	Department of Pediatrics, Aga khan university Hospital	30	<15 years	Cyanotic congenital heart disease (11), meningitis (6), septicaemia (7); idiopathic (5)	Parietal (55%), Frontal (28%); Temporal (13%); Occipital (4%)	Solitary (n-29); Multiple (n-1)	Fever (96%), headache (45%), vomiting (60%), seizure (45%)
Kafle et al, 2018	Department of Neurosurgery, Tribhuvan university teaching hospital Kathmandu	27	0-5 years (12); 6-10 years (7); 11-16 years (8)	Otogenic (10); Tetrology of Fallot (6); Tubercular (3)	Temporal (9); Frontal (6); Parietal (4)	Solitary (25), Multiple (5)	Headache (n-20); ear discharge (n-10); vomiting (n-5)
Present study	Department of Pediatrics, Neurosurgery Institute of medical Sciences, BHU	30	<5 years (6); 5-10 years (13); > 10 years (11)	Otogenic (n -15); Congenital cyanotic heart disease (n-5), Mastoiditis (n-2), Idiopathic (n-8)	Temporal lobe (n-11); Parietal lobe (n-10); Frontal lobe (n-6); Cerebellum (n-1); Intraventricular rupture (n-2)	Solitary (n-30)	Fever (n-11); Seizures (n-8); Headache (n-7); altered sensorium (n-3)
Authors	Most common Neuroimaging finding	Culture positivity		Common pathogen	Treatment	Mortality	Poor prognostic factors
Malik et al.; 1993	Well defined ring enhancing lesion (31)	54.8% Pus (17/31)		Staphylococcus Proteus Pseudomonas		44.7%	Grade III/IV Coma at admission, Age <2 years Multiple abscesses
Hegde et al.; 1986	Ventriculography, Angiography was done	90%		Staphylococcus, proteus mirabilis, Hemophilus aphrophilus, sterptococci, B Fragilis	Antibiotics + Aspiration (n -84) + Excision (few)	21%	Degree of impairement of conciousness at admission
Singh et al.; 2001	Capsule formation	Pus (10/48-20.83%)		Staph Aureus (n-1); strept viridians (n-1); E coli (n-1); Proteus (n-1); Mixed infections (n-5)	Antibiotics + Aspiration (n-44) + Excision (n-4)	2.9%	GCS <6 at time of presentation to hospital
Borgohain et al 2015	Single ring enhancing lesion	Pus (12/17 - 70.58%)		Klebseilla -5; Pseudomonas -7	Antibiotics + Aspiration (n-12) + no excision	Nil	----
Atiq et al, 2006	Single ring enhancing lesion	Pus (27/30-90%); Blood (11/23-47.82%)		Sterptococcus milleri (8/27)	Antibiotic + Aspiration (14) + Excision (6)	5/30 - 16.66%	Deranged Sensorium. midline shift, cerebral oedema
Kafle et al, 2018	Single ring enhancing lesion	Pus (7/27 - 25.9%)		Psuedomonas aeruginosa (n-5); E Coli (n - 1); multiple organism (n - 1)	Antibiotic + Aspiration (n- 23) + Excision (n-2)	2/27 - 7.40%	GCS at time of presentation
Present study	Single ring enhancing lesion	Blood culture (5/30-16.7%); Pus (4/16 - 25%)		Methicillin resistant Staphylococcus aureus (n-4); Proteus mirabilis (n-4); Candida Sp (n-1)	Antibiotics + Burr hole aspiration (n-10) + Craniotomy (n-6)	5/30 - 16/7%	Poor GCS score at time of presentation, Intraventricular rupture

Neuroimaging was done in all cases. CT scan was done in 25 cases and MRI was done 5 cases. Most common neuroimaging finding was ring enhancing lesion. This has been reported in previous studies from India and abroad.[67891011] The only added advantages of MRI over CT Scan are: better differentiation of oedema from necrosis, more sensitivity in detection of early cerebritis, greater sensitivity for early satellite lesion.[322] Culture yield was low in our study with blood culture positive in 16.7% of cases and pus culture positive in 25% cases, respectively. This low positivity of culture is attributed to the antibiotics children received from previous hospitals and general practitioners prior to admission. There has been varying reports of culture yield from various studies ranging from 20.83-90% from pus. Positivity rate of pus culture is high as reported previously.[23] Common pathogen reported in our cohort were Methicillin resistant staphylococcus aureus, Proteus mirabilis and Candida Sp. This has been reported from previous Indian studies.[678] This shows that there has been emergence of Methicillin resistant staphylococcus aureus which warrants the use of vancomycin as one of antibiotic of choice in our treatment protocol. All cases required initial stabilization followed by initiation of intravenous antibiotics (Vancomycin, Cefotaxime and Metronidazole) for at least 2-3 weeks, followed by oral antibiotics for 4-6 weeks depending upon culture sensitivity report. This antibiotic protocol formulated by our department based on previous one year culture reports in brain abscess. Neurosurgical burr hole aspiration was done in large abscess (>2.5 cm in diameter) in 10 cases with excision in 6 cases. This has been the most consistent approach of treating brain abscess in previous studies too.[67891011]

There were 5 deaths in this cohort. 2 were associated with intraventricular rupture and 3 have poor GCS at time of presentation. Previous reported studies from India have highlighted these two factors with high mortality in their studies too.[678]

Limitations of our study were small sample size, no follow up data and lack of immunodeficiency work-up.

CONCLUSION

Paediatric brain abscess is a challenging disease. It requires high index of suspicion by primary care physicians and early referral to tertiary centre for multi-modality management in order to achieve a good outcome.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.