the most commonly reported etiologic microorganisms of this rare condition are citrobacter diversus proteus mirabilis , pseudomonas aeruginosa , serratia marcescens , and other enterobacteriaceae .
a male preterm of approximate 34 weeks gestation , weighing 1.9 kg , appropriate for gestational age was delivered vaginally to a primigravida mother at a private nursing home .
the baby had cried immediately after birth and was asymptomatic on day 1 of life . on day 2 , the baby was admitted in neonatal intensive care unit of a tertiary care hospital with complaints of excessive cry and refusal to feed . there was a history of leaking per vaginum for 3 days prior to the delivery .
the baby exhibited weak cry , shallow , and irregular breathing pattern with the inability to maintain oxygen saturation in room air .
fever , progressively worsening respiratory distress , apnea , cyanosis , seizures , bulging anterior fontanelle , vomiting , and pallor were , however not observed .
neurological examination revealed normal occipito - frontal circumference , wakefulness , reflexes and physiological hypotonia without a focal neurological deficit .
total leukocyte count = 4000/l , absolute neutrophil count = 1800/l , serum c - reactive protein = 4.8 mg / dl ( semiquantitative latex slide agglutination kit , vital diagnostics , thane , india , normal cut - off limit = 0.6 mg / dl ) normal blood sugar ( 4.62 mmol / l ) , serum calcium ( 2.35 mmol / l ) , normal chest x - ray and an arterial blood gas .
the patient was administered a combination of cefotaxime at 50 mg / kg / dose q 12 hourly and amikacin at 7.5 mg / kg / dose q 12 hourly owing to laboratory confirmation of sepsis .
the cerebrospinal fluid examination was normal with sterile culture and with no micro - organisms seen in the gram - stained slide , thus , indicating the absence of meningitis . due to the persistent clinical features of sepsis
, antibiotics were changed to intravenous vancomycin at 10 mg / kg / dose q 12 hourly and meropenem at 20 mg / kg / dose q 12 hourly after 48 h of initiation of therapy . the persistence of shallow and irregular breathing pattern prompted us for cranial ultrasonograms on day 5 which revealed multiple hypo - echoic lesions in bilateral parietal lobes . magnetic resonance imaging ( mri )
brain was subsequently performed on day 6 which showed multiple hypo - dense lesions with peripheral enhancement suggestive of intra - parenchymal abscesses in bilateral fronto - parietal and left basal ganglionic region [ figure 1a and b ] .
intravenous vancomycin was continued in same doses , but dose of meropenem was increased to 40 mg / kg / dose q 12 hourly to facilitate the drug availability at the site of lesions .
repeat blood culture drawn at this time grew kliebsiella pneumoniae after 48 h of incubation which was sensitive to ciprofloxacin and piperacillin  tazobactam . on day 10 ,
due to minimal change in the general condition and respiratory pattern , vancomycin and meropenem were replaced by intravenous piperacillin 
an improvement in general condition was observed in the ensuing 72 h , following which , the neonate started feeding well and was subsequently discharged after 6 weeks of therapy . on a 3 months follow - up , a repeat mri brain scan [ figure 2 ] revealed complete resolution of lesions as shown in the earlier report .
the baby had a normal neurological examination and developmental milestones at 9 months of age .
mri brain images prior to initiation of therapy : ( a ) axial t2 image shows hyper - intense areas surrounded by hypo - intense rim seen involving the left basal ganglion , and in bilateral fronto - parietal locations .
( b ) sagittal contrast t1 image shows thick peripheral rim enhancement of the lesions in left basal ganglion and in the left parietal lobe .
both images a and b are suggestive of parenchymal brain abscesses mri brain images post - therapy : axial t1 ( left ) and sagittal ( right ) contrast mri brain images on post - therapy follow - up scan at 3 months age shows no abscess in the corresponding regions of brain parenchyma and is suggestive of their complete resolution
gram - negative micro - organisms commonly citrobacter diversus , proteus and pseudomonas species have been implicated in the pathogenesis as they bear the propensity to invade nervous tissue and cause necrotizing vasculitis .
although , klebsiella is the most common organism causing neonatal sepsis in developing countries , , it has been reported in few cases of brain abscess in the world literature . however , in one of the largest series of 30 neonates with brain abscess in a tertiary center , no case was attributed to klebsiella species .
this could be due to its lesser tendency to cause necrotizing lesions as compared to citrobacter and proteus species .
volpe has emphasized that the bacteria cause meningitis and vasculitis initially , which may further , rarely complicate and result in the formation of a brain abscess . in this case , there was history of leaking per vaginum in the mother for 3 days prior to delivery which was probably followed by neonatal sepsis and hematogenous seeding of the brain parenchyma resulting in the multiple abscesses with no initial meningeal involvement .
have hypothesized that the direct hematogenous seeding of the parenchyma could be an equally important pathogenetic mechanism for an abscess to develop and a meningeal involvement may not be an essential prerequisite always .
the colonization of brain parenchyma during sepsis can be explained by the physiological right - to - left shunt of the neonatal circulation .
the usual clinical presentation of brain abscess in neonatal period consists of irritability , bulging fontanelle , and rapid rise in head circumference with wide separation of sutures , vomiting , seizures , and poor feeding .
the presence and persistence of shallow and irregular respiratory pattern with the inability to maintain oxygen saturation in room air necessitated a cranial ultrasonography and mri brain .
the management of neonatal brain abscess is influenced not only by the anatomic location , number , size , stage , and nature of the abscesses but also by the age and neurological status of the patient .
medical management saves the patient from the stress and surgical complications especially in a neonate , who may present with significant surgery - related neurological deficits and hemorrhage .
the duration of the antibiotic course is usually 68 weeks and longer for immunocompromised patients .
however , the right dose and duration of antimicrobial agents for neonatal brain abscess is poorly studied . in this case , there was a poor response to empirical meropenem therapy despite an increase in its dose .
meropenem penetrates the blood - brain barrier well when the meninges are inflamed and achieves an excellent minimum inhibitory concentration for almost all gram - negative pathogens but neonatal data about its penetrative ability in the absence of meningeal inflammation or within an abscess cavity are lacking . on the other hand , surgical intervention provides samples for accurate diagnosis , reduces the mass of an abscess , improves the efficacy of the drugs used for treatment and in some conditions allows intrathecal , intra - ventricular or intra - cavitory administration of antibiotics .
response to a 6 weeks course of piperacillin  tazobactam obviated the requirement for surgical intervention in this case .
aspiration was not attempted in this case owing to smaller multiple lesions which were inaccessible to this procedure .
various studies have highlighted the poor iq scores and subsequent poor scholastic performance . in this case , the patient exhibited appropriate developmental milestones on follow - up . to conclude ,
apart from the typical features , a clinician should be aware of atypical features such as shallow and irregular breathing , inability to maintain oxygen saturation in room air , and absence of the usual clinical features . a strong clinical suspicion may thus be required for diagnosis in such cases .
 brain abscesses occur as an uncommon complication of bacterial meningitis in the neonatal period . 
 a 34 weeks preterm at - risk neonate presented with abnormal breathing pattern and inability to maintain the oxygen saturation in room air . magnetic resonance imaging ( mri ) 
 study revealed intra - parenchymal brain abscesses in the left basal ganglion and bilateral fronto - parietal regions . 
 intravenous piperacillin  
 tazobactam was commenced and continued for 6 weeks in neonatal intensive care unit . 
 no surgical intervention was required . 
 the patient responded to the medical management and was discharged after the documentation of radiological clearance in repeat mri study . 
 no complications were recorded . 
 an appropriate neuro - developmental outcome was observed on follow - up . 
 brain abscesses may not be preceded by meningitis in all neonates . 
 a strong clinical suspicion is required for the diagnosis especially in cases with atypical presentation . 
Introduction
Case Report
Discussion
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