1
ENTEROBACTER AMNIGENUS A NEW CAUSE FOR NEONATAL
SEPSIS

• Yousef K. Abu-Osba Amer Ammari Khalil
• Salameh Mamoun Shalabi Kamal El-Haj
• Neonatal Medicine Services, Jordan Hospital,
  Amman, Jordan
• Neonatal Medicine Services, and Microbiology
  Section,
• Hamad General Hospital, Doha, Qatar

2
ENTEROBACTER AMNIGENUS NEONATAL SEPSIS Clinical
Characteristics

• Case SEX APGAR B.W. AT Onset of
  sepsis 1 5 (g)
  Weight Age d. 1 m 2 6 880
  1120 47 2 f 7 9 1000 1020 14
  3 f 7 8 1100 940 9 4 m 7 9 1020
  1020 9 5 f 7 8 1040 1000 9

3
ENTEROBACTER AMNIGENUS NEONATAL SEPSIS Clinical
Presentation

• NO T. H.R A. Dis. Acidosis
  Glucose UVC UAC P.Line
• C mmol/L Pre / During
•  
• 1 39 194 -
  4.2 /- /-
  
• 2 36.7 180 -
  4.6 -/- /-
• 3 37 158 - 13.4
  /- /
• 4 35 150 - - 9.7
  / -/-
• 5 36.7 175 - - 9.8
  / /

4
ENTEROBACTER AMNIGENUS NEONATAL
SEPSISHematological Presentation

• NO WBC BAND RATIO Platelets
  Blood Tx (1.1-6.0) (500) (.12)
  (1000)
• 
  
• 9200 22/19 1.2
  36 YES
• 21000 16/61 .26 64
  YES
• 28300 16/72 .22 33
  YES
• 7600 0/46 0 26 YES
• 12200 0/86 0 26 YES
• Ref. Revised Reference Ranges For Circulating
  Neutrophils in Very-Low Birth-Weight Neonates.
  (PEDIATRICS Vol. 94 No. 1 July 1994)

5
ENTEROBACTER AMNIGENUS NEONATAL
SEPSISImmunological Presentation

• NO IMMUNOGLOBULINS ESR
  CRP
• IgG IgA IgM mm
  gt 6mg/L
• 1 660 16 62 25
• 2 208 7 22 27
• 3 - - - 9
• 4 465 10 12 2
• 5 419 33 31 8

6
ENTEROBACTER AMNIGENUS NEONATAL SEPSIS Sepsis
Episodes During Hospitalization

•  
• Case BEFORE DURING AFTER
• (Age d.) (Age d.) (Age d.)
•  
• 1 CANDIDA (40) E. FECALIS E. AGGLOMERANS (76)
• 2 K. PNEUMONIAE (11) -- SERRATIA
  MERSESCANS (30)
• S. EPIDERMIDIS (60)
• 3 -- S. EPIDERMIDIS --
• 4 -- -- S. MERSESCANS (26)
• S. EPIDERMIDIS (75)
• 5 -- - E. FECALIS (49)
• MICROCOCCUS (79)

7
ENTEROBACTER AMNIGENUS NEONATAL
SEPSISAntibiotics Treatment

•  
• Case Treatment
  Culture -ve
• Previous During Sepsis Days Post
  Treatment
•  
• 1 AMPH,AMP AMK (12D), CPX (1D) 8
  D
• 2 - AMK (14D), CPX (14D) 5 D
• 3 - IMP (14D), AMK (19D) 13 D
• CPX (10D)
• 4 AMP, CPX AMK (15D), CPX (15D) 3 D
• 5 - IMP (15D), AMK (17D) 11D
• CPX (10D)
• AMPH Amphotericin, AMP Ampicillin, CPX
  Cephotaxime, IMP Imipenem.

8
ENTEROBACTER AMNIGENUS NEONATAL
SEPSISENTEROBACTER AMNIGENUS BIOGROUP 2
(MIC)

•  SENSITIVE RESISTANT  
• AMPICILLIN (gt32/16) CEFOTITAN (gt32)
• AMIKACIN SULBACTAM
  (gt32/16) CEFTRIAXONE (gt64)
• CPROFLOXACIN lt.25) AMPICILLIN (gt32)
  CEFTAZIDIME (gt32)
• COTRIMOXAZOLE AUGMENTIN
  gt32/16) CEFTIZOXIME (gt32)
• GENTAMICIN AZTREONAM (gt32)
  CEFUROXIME
• IMIPENEM (lt.5) AZLOCILLIN
  (gt64) CEPHALOTHIN
• NETILMICIN (4) CEFAMANDOLE
  (gt32) CARBENICILLIN (128)
• CHLORAMPHENICOL (8) CEFONICID (gt16)
  MEZLOCILLIN (gt128)
• CEFOPERAZONE
  (gt32) TICARCILLIN (gt128)
• CEFOTAXIME (gt64) TICARCILLIN (gt128)
• PIPERACILLIN

9
ENTEROBACTER AMNIGENUS NEONATAL SEPSIS
ENTEROBACTER AMNIGENUS IDENTIFICATION

• REACTIONS AFTER 2 DAYS OF INCUBATION
• BIOGROUP 1 BIOGROUP 2
•  Lysine decarboxylase (LDC) -
  -
• Arginine dihydrolase (ADH) -
  v
• Ornithine decarboxylase (ODC) v
  
• Growth in KCN
• Fermentation of
• Sucrose -
• D-sorbitol -
  
• Raffinose
  -
• Yellow Pigment -
  -

10
ENTEROBACTER AMNIGENUS A NEW CAUSE FOR NEONATAL
SEPSIS

• SUMMARY - 1
• We report for the first time in our area sepsis
  secondary to ENTEROBACTER AMNIGENUS in 5
  premature infants, who had positive blood
  cultures and suffered from clinical signs and
  symptoms of infection.
• Enterobacter amnigenus was isolated from both the
  aerobic and anaerobic bottles on several
  occasions. Identification of the source of
  infection was difficult to ascertain.

11
ENTEROBACTER AMNIGENUS A NEW CAUSE FOR NEONATAL
SEPSIS

• SUMMARY - 2
• Aggressive treatment with antibiotics and
  supportive measures were required.
• All isolates were resistant to third generation
  cephalosporins and sensitive to amikacin and
  gentamicin.
• All patients survived.

12
ENTEROBACTER AMNIGENUS A NEW CAUSE FOR NEONATAL
SEPSIS

• Conclusions
• Enterobacter amnigenus can cause sepsis in
  susceptible or immuno-compromised infants like
  very premature infants, which required aggressive
  therapy.
• Amikacin, gentamicin and imipenem are the drug of
  choice.
• Imipenem may be used if aminoglycosides are
  contraindicated.