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Page 2 of 8 Kafle et al. Neuroimmunol Neuroinflammation 2018;5:24 I http://dx.doi.org/10.20517/2347-8659.2018.10

Conclusion: With the advent of modern technology in neuroimaging, mortality due to brain abscess has significantly
decreased. Joint involvement of the otorhinolaryngology team and efforts in addressing the primary source have further
helped in improving outcomes in cases of otogenic brain abscess. Hence, source control is of paramount importance in
managing the brain abscess.

Keywords: Abscess, otogenic brain abscess, tubercular abscess

INTRODUCTION
Though the incidence of brain abscesses is as low as 2% in the western world, it accounts for up to 8% of intra-
cranial masses in developing countries . There is a paucity of data about the exact incidence of brain abscess
[1,2]
in Nepal. Despite recent advances in imaging techniques, laboratory modalities, surgical interventions and
antimicrobial treatment, brain abscess still remains a challenging clinical entity with substantially high case
fatality rates. This is attributable to changes in epidemiology, clinical spectrum, predisposing factors and the
prevalence of implicated bacterial pathogens. Brain abscess contributes to high mortality, and even more
so in immune compromised patients. Different organisms have been implicated in its etiology comprising
of bacteria, mycobacterium, fungi, parasites (protozoa and helminthes) and cryptogenic . Brain abscess
[3]
formation may occur after neurosurgical procedures or head trauma. Brain abscesses due to contiguous
spread from parameningeal foci of infection (e.g., the middle ears, mastoids, and sinuses) are common in
developing countries. Many of the patients with brain abscess have concomitant ear infection and/or cardiac
problems, especially cyanotic heart disease. Formation of brain abscess after penetrating head injuries and
following cranial surgery is also common. The present study presents the demographic profile, surgical
management, microbiology and outcomes at our centre.

METHODS
This is a prospective observational study conducted over the period of two and half years (from September
2014 to March 2017) at Institute of Medicine (IOM), Tribhuvan University Teaching Hospital Kathmandu,
Nepal. Data regarding patient characteristics, clinical profile, etiology, microbiology profile, management
algorithm and complications were collected and analyzed. All cases with brain abscess admitted to IOM
were included in the study. Individuals with brain abscess operatively managed in other hospitals and
referred to our centre postoperatively were excluded from the study. Clinical findings at presentation were
noted and subsequently contrast enhanced computed tomography (CECT) was done in all cases. High
resolution computed tomography (HRCT) of the involved ear was also performed in indicated cases.
Initially, hyperosmolar therapy (mannitol-1 gm/kg/ IV dose q 8 hourly and dexamethasone 1 - 4 mg IV q
8 hourly depending up on the weight of patient) was instituted until surgical intervention was completed
and steroids were tapered. Antiepileptic medications were instituted for all supratentorial abscesses for a
minimum of 1 month and continued in patients with seizures for a period of 2 years. Burr hole and drainage
is the standard procedure performed in our centre after marking the operative site on CT scan. Craniotomy
and abscess cavity excision were required in very few cases. After drainage, obtained samples were sent for
Gram stain, culture and sensitivity. Anaerobic culture was not done due to resource constraints. Patients
were treated with initial empirical triple broad spectrum antibiotics which included vancomycin 15 mg/kg
IV 8 hourly, ceftriaxone 25 mg/kg IV in two dived doses and metronidazole 15 mg/kg IV in 3 divided
doses. Narrowing of antibiotics was made accordingly and continued for 6 weeks if culture sensitivity was
positive for a specific organism. Follow-up head CT was performed in 1 week and every 2 weeks thereafter.
Head CT was performed in between if indicated by alteration in clinical status of the patient, i.e. drop in
Glasgow Coma Scale by ≥ 2 points. Repeat aspiration was performed if the size of the abscess was found to
be increasing or clinical status was not improving. Patients were labeled as cured radiologically if there was
no residual abscess cavity on CECT after 6 weeks of treatment.