In a neonate with respiratory distress, pneumonia is diagnosed in the presence of a positive blood culture or if any two of the following are present(NNPD, 2002)13. Existing or predisposing factors: maternal fever, foul-smelling liquor, prolonged rupture of membranes or gastric polymorphs more than 5per high power field. The clinical picture of septicemia (poor feeding, lethargy, poor reflexes, hypo, hyperthermia, abdominal distension etc). X-ray picture suggestive of pneumonia. Positive sepsis screen (as for septicemia).Intramural report from NNPD (2000)31 showed that of total clinical cases of systemic infection, pneumonia was diagnosed in 17.
5% but in an extramural report it was 21.7%.The incidence of meningitis:Suspected bacterial infection is confirmed often, but not uniformly, by positive results of culture of CSF or blood. CSF cultures should be obtained in all symptomatic infants.
Despite the close relationship between bacterial sepsis and meningitis, it has been estimated that 15-30% of infants with CSF-proven meningitis will have negative blood cultures (Malbon et al, 2006)32. A recent study by Garges et al, (2006)33 from Durham, emphasized that no single CSF value can be relied upon to exclude neonatal meningitis except CSF culture.
The NNPD 200334 report for extramural babies revealed meningitis to be present in 19.6% of neonates with systemic infections. Several studies report that preterm birth and low birth weight are the most common perinatal factors associated with the development of meningitis in newborn (Issacs & Moxon 199135; Klein & Marcy 199024; Louvois & Harvey, 199036).
Meningitis is an important cause of illness in newborn infants with high mortality and frequent neurological sequelae. About 20-30% of neonatal septicemia, whether early or late, is complicated by bacterial meningitis (Isaacs & Moxon, 199135; Louvios & Harvey, 199036).The incidence of meningitis as reported by various authors is 9.2% per thousand live births. (Issacs & Moxon, 199135).Profile of organisms causing sepsis:Bacteria causing neonatal sepsis in developing countries:Gram-negative organisms: Klebsiella pneumonia (n=5; 29%) and Pseudomonas aeruginosa (n =4; 24%) were the commonest isolates followed by group B Streptococcus (n=3; 18%) and Escherichia coli (n = 2; 12%). (Alam et al, 2014)2. Klebsiella, Escherichia coli, Pseudomonas, Salmonella (Karthikeyan et al 200136; Tallur et al, 200038; Karunasekara et al 199939; Moreno et al, 199440).Gram-positive organisms: Staphylococcus aureus, coagulase-negative staphylococci (CONS), Streptococcus pneumonia and Streptococcus pyogens are most commonly isolated. [Karthikeyan et al, 200136 (India); Mulholland et al, 199941; (Gambia)].
Early-onset infection: E. Coli, Group B streptococcus, Enterobacter, Enterococcus, H. influenzae and Listeria monocytogens are most commonly associated.A study from India by Vigneshwaran and Edwin (2010)42, showed that of the 100 newborns investigated for sepsis, 32 (32%) showed positive blood culture reports. Out of the 32 positive blood cultures, 28 (87.5%) were gram-positive bacterial isolates and only 4 (12.5%) were gram-negative bacteria. The commonest isolate was coagulase-negative Staphylococcus, (59.4%) followed by Staphylococcus aureus (21.9%). Though CONS is usually considered as a skin contaminant, the presence of this bacterium in blood in critically ill babies, especially in the 2nd week of life should be considered as significant and should be treated, especially when it is isolated repeatedly. However if only early onset septicemias were considered, these were predominantly caused by gram-negative bacteria and Staphylococcus aureus.
Sundaram et al (2009)43, observed that the bacterial pathogens that cause EOS in developing countries differ from the microbes that cause disease in the United States, Canada, Europe, Australia, and other more developed countries. For ill-defined reasons, the prevalence of GBS disease is lower in developing countries. As developing countries sustain economic development, the prevalence of different bacterial pathogens assumes a profile closer to developed countries.Bromiker et al (2013)44, isolates 97 different organisms from 94 infants (1.03 per 1,000 live births). By univariate analysis, gestational age 32 weeks or less, chorioamnionitis and rupture of membranes 18 hours or more, were significantly associated with both Gram-negative sepsis and antibiotic resistance. By multivariate analysis, was significantly associated with both outcomes, while gestational age 32 or fewer weeks was only associated with antibiotic resistance. For more than 24 h is associated with an increased proportion of Gram-negative organisms and ampicillin resistance in early-onset neonatal sepsis.
The authors concluded that antepartum antibiotic therapy and its ramifications need to be continuously monitored and prospectively studied.In 2001 France issued a new set of guidelines for the use of antenatal antibiotics (AA). These guidelines recommended intrapartum antimicrobial prophylaxis (IAP) to prevent group B streptococcal (GBS) disease and AA to prolong pregnancy in the event of preterm premature rupture of membranes (AA for PPROM). Kuhn P et al, (2010)45 conducted a study to determine the effects of AA, recommended by national guidelines, on the incidence and distribution of pathogens in early-onset neonatal sepsis (EONS). They performed a population-based, prospective, observational study of level II and III perinatal centres throughout the region of Alsace, a northeastern area of France. The study population included all neonates with confirmed or probable EONS, who were treated with antibiotics for at least 5 days. They analysed exposure to AA, as well as clinical and microbiological data obtained from medical records. A total of 20, 131 neonates were born during the study period, and 217 were included in the study. Of these, 24 subjects had confirmed sepsis, 140 had probable sepsis and 53 had possible EONS.
The overall incidence of confirmed EONS was 1.19 per 1000 births. The infecting bacteria was GBS in 15 of 24 (62.5%) confirmed EONS cases (incidence: 0.75 per 1000 births). Escherichia coli was identified in 6 of 24 (25%) cases of confirmed EONS (incidence: 0.3 per 1000 births). Among E. coli infections (n= 36), amoxicillin resistance (n= 18) was statistically linked with AA use (p = 0.045). This link was significant in cases of PPROM (p = 0.015), but not when IAP was administered to prevent GBS disease (P = 0.264). IAP was not given in 18 of 60 (30%) cases and 32 of 93 (34%) cases, despite positive screening or the presence of risk factors for EONS, respectively. These workers concluded that Group B streptococcus remains the predominant pathogen in the era of AA. Aminopenicillin-resistant E. coli infections seem to be linked to prolonged AA in cases of PPROM and appear to preferentially affect preterm infants.
Risk Factors for developing sepsis
Early onset sepsis: Early-onset sepsis usually presents within the first 72 hours of life. In severe cases, the neonate may be symptomatic in utero (fetal tachycardia, poor beat variability) or within a few hours after birth. The source of infection is generally the maternal genital tract. Clinically, neonates usually present with respiratory distress and pneumonia. Presence of some perinatal risk factors has been associated with an increased risk of early-onset sepsis. Recommendations from developed countries suggest that the presence of 2 risk factors should be considered an indication for starting antibiotics. However, the main organism in their setup is group B streptococcus (GBS) which is not a problem in our neonatal intensive care units. Hence, their recommendations may not be applicable to our setting. Since definitive data for our setting is lacking, an empirical approach has been recommended. Presence of the following high-risk factors has been associated with an increased risk of early-onset sepsis. (Takkar et al, 197446; Singh et al, 199447).
- Low birth weight (less than 2500 grams) or preterm baby.
- Febrile illness in mother within 2 weeks prior to delivery.
- Foul smelling and/ or meconium stained liquor amnii.
- Rupture of membranes for more than 24 hours.
- Single unclean or more than 3 vaginal examinations during labor.
- Prolonged and difficult delivery with instrumentation (sum of 1st and 2nd stage of labour more than or equal to 24hours)
- Perinatal asphyxia (Apgar score less than 4 at 1-minute of age) or difficult resuscitation presence of foul smelling liquor or three or more of the above-mentioned risk factors should be considered to have early-onset sepsis and treated with antibiotics.
Presence of 2 risk factors should be investigated with a septic screen and treated accordingly (Shankar et al, 200148).
Maternal Risk Factors
Maternal Chorioamnionitis:Infants of the mother with a diagnosis of clinical chorioamnionitis.
Definition: Clinical chorioamnionitis is defined by the presence of intrapartum maternal fever (>37.80 C) in a period from onset of labour to delivery with two or more of the following features:
- Maternal Tachycardia (>100 beats/minute)
- Fetal tachycardia (> 160 beats/minute)
- Uterine tenderness
- Malodourous vaginal discharge
- Maternal Leukocytosis (>15000/Cumm) (Alexender et al, 1999)
Alam et al (2014)2, in a study Pakistan found that Maternal fever (p = 48 hr. (p < 0.001; aOR, 8.2), neonatal prematurity < 34 weeks (p < 0.001; aOR, 4.1) and low birth weight.
Cite this essay
Statistics of Clinical Cases of Systemic Infection. (2019, Aug 20). Retrieved from https://studymoose.com/statistics-of-clinical-cases-of-systemic-infection-essay