ELIZABETHKINGIA MENINGOSEPTICA BACTEREMIA IN A NEONATE: A RARE CASE REPORT FROM A TERTIARY CARE CENTRE OF TRIPURA

Blood from a two day old male baby with history of respiratory distress and meconium aspiration was sent to the Department of Microbiology for culture. Blood culture yield non haemolytic small colonies of 1-2 mm on Blood agar and no growth on MacConkey agar.Based upon the colony characteristics, biochemical reactions, antimicrobial susceptibility pattern and identification by conventional and Vitek 2 Compact system, the isolate was identified as Elizabethkingia meningoseptica which is a rare cause of bacteremia in neonates.

The baby was diagnosed as a case of pre-term low birth weight infant with respiratory distress due to meconium aspiration and sepsis. On examination, baby's Pulse rate (PR) was 146/min, regular, Respiratory Rate (RR) was 89/min, capillary refill time (CRT) <3 seconds, Skin pinch<2 seconds. Cyanosis, icterus, pallor was absent. SPO2 was 88% without oxygen measured from right arm.
Laboratory investigations revealed Hb% level of 16g/dl with leucocytosis (TLC-13,000/mm 3 ) and neutrophilia (76% in DLC). C-reactive protein was 5mg/dl and serum Procalcitonin level was 4.8 ng/ml. Total bilirubin was 2.7 mg/dL and direct bilirubin was 0.1 mg/dL. Blood urea and creatinine was 44 mg/dL and 0.6 mg/dL respectively. Sodium was 145 mEq/L and potassium was 4.2 mEq/L. Chloride and calcium was 122 mEq/L and 8.5 mg/dL respectively. Random blood sugar was 88mg/dl. Peripheral smear study showed normocytic normochromic red blood cell.
Baby was admitted in the neonatal intensive care unit (NICU) and was started on Injection Amikacin 30 mg IV once daily and Injection Cefotaxime 100mg IV twice daily.
Two sets of blood cultures, each comprising of two bottles, were collected as per protocol followed in the Department. One set was collected before initiation of antimicrobial therapy and the second set was collected before administration of second dose of antibiotic. [6] Blood culture was incubated in BACT/ALERT 3D (Biomerieux) as per manufacturer's protocol. [7] Positive signal was given after 48 hours of incubation from 2 bottles of first set and one bottle of second set. Subculture was performed after positive signal in the automated system in Blood agar and MacConkey agar plates. Gram stain was performed from the blood culture bottles which showed gram negative bacilli. Gram stain report was communicated to the physician over telephone. After 24 hours of aerobic incubation at 37 o C, smooth, circular, non haemolytic, small colonies of 1-2mm size, with regular margin and entire edge were isolated on all three blood agar plates. There was no growth on MacConkey agar plates. On Gram staining from colonies of Blood agar, gram negative bacilli were seen and the organism was non-motile. Organisms were identified based on conventional biochemical tests [8] and by Vitek 2 Compact automated identification and AST system as per manufacturer's protocol. [9]  The Antimicrobial sensitivity tests were performed using both Vitek 2 Compact system and micro-broth dilution method as per CLSI protocol M45, 3 rd edition. [10] The isolate was sensitive to Cefoperazone/sulbactam (minimum

Discussion:-
Elizabethkingia meningoseptica is an emerging healthcare-associated infection, especially among premature, low birth weight neonates and immunocompromised individuals. Its unusual antimicrobial sensitivity and resistance patterns along with inherent resistance to colistin makes the organism difficult to treat, thus posing a great therapeutic challenge. [11,12] The infection caused by E. meningoseptica may be misdiagnosed and underreported because of lack of high index of clinical suspicion and difficulty in sample collection, as most cases occur in pre-term and newborn infants.It should be considered as a cause of sepsis and meningitis in premature low birth weight infants in any neonatal intensive care unit as several reports have been emerging about this infection. [13]