Micro-Erythrocyte Sedimentation Rate in Neonatal Sepsis of a Tertiary Hospital: A Descriptive Cross-sectional Study

ABSTRACT Introduction: Neonatal sepsis is the most important cause of morbidity and mortality among low birth weight and preterm babies in developing countries. The main objective of this study is to find the level of micro-Erythrocyte sedimentation rate in neonatal sepsis. Methods: This is a descriptive cross-sectional study conducted at the neonatal unit over six months period (November 2019 to April 2020). All preterm, term and post-term babies with neonatal sepsis delivered at Kathmandu Medical College Teaching Hospital were enrolled. Ethical clearance was received from the Institutional Review Committee of Kathmandu Medical College (Ref: 181020191). Convenient sampling method was applied and statistical analysis was done with Statistical package for social sciences 19 version. Results: Out of 75 babies, confirm sepsis is 13 (17.3%), probable sepsis is 40 (53.4%) and suspected sepsis is 22 (29.2%). Micro-Erythrocyte sedimentation level is elevated (>15mm in 1st hr) in 25 (33.3%) babies with a mean micro-Erythrocyte sedimentation level 9.32±5.4 (2-18) mm in 1sthr. The elevated micro- Erythrocyte sedimentation level was seen in relation to sepsis types and C-reactive protein. Conclusions: The bedside micro-Erythrocyte sedimentation level aids in the diagnosis of neonatal sepsis.


INTRODUCTION
Neonatal sepsis is the most important cause of mortality among low birth weight and preterm babies in developing countries. 1 In Nepal, the neonatal mortality rate is still high (21 per 1000 live births). Causes of neonatal deaths are sepsis, perinatal asphyxia, prematurity, and low birth weight. 2,3 Maternal risk factors eg. Prolonged rupture of membranes (PROM) > 18 hrs., positive high vaginal swab culture, intrapartum fever, and neonatal risk factors eg. birth weight <1500gm, gestational age <34 wks, low APGAR score contributes for sepsis. 4 Sepsis is define as signs and symptoms of infections with or without accompanying bacteremia with the growth of bacteria within first month of life and consists of septicemia, meningitis, pneumonia, and urinary tract infection. 5 Prompt diagnosis, good nursing care, and antibiotics aids to save babies with sepsis. 6 Blood culture is the gold standard for sepsis diagnosis, but it is time-consuming and needs equipped lab. 7,8 Free Full Text Articles are Available at www.jnma.com.np in neonatal sepsis at a tertiary hospital.

METHODS
A descriptive cross-sectional study was carried out on neonates with neonatal sepsis at 10 bedded Neonatal Intensive Care Unit (NICU) of the Pediatrics Department of Kathmandu Medical College Teaching Hospital over six months period (November 2019 -April 2020). Perinatal Mortality Rate (PMR) of this tertiary hospital is 10 per 1000 births and Neonatal mortality rate (NMR) is 4.5 per 1000 live births. 9 All preterm, term and post-term neonates admitted in the NICU with a diagnosis of suspected sepsis, probable sepsis and confirm sepsis were enrolled. Risk factors and laboratory criteria for the diagnosis of neonatal sepsis is mentioned in Box 1. 10 mottling of the skin and irritability with normal five laboratory septic screening test mentioned in Box 1. 4,10 A neonate clinically have above mentioned clinical signs and symptoms with at least two of the five laboratory screening tests positive mentioned above in box 1 with negative blood culture is diagnosed as probable sepsis. 11 Confirm sepsis is define as neonate with above mentioned clinical sign/symptoms with positive two out of the five laboratory screening tests mentioned above with having blood, urine or cerebrospinal fluid culture yielding an organism. 11 Neonates fulfilling inclusion criteria were drawn venous blood for blood culture and sensitivity (CS), total leukocyte count (TLC), differential count (DC), absolute neutrophil count (ANC), hemoglobin(Hb), microerythrocyte sedimentation rate (micro-ESR), C-reactive protein (CRP) and peripheral smear for band cells. Blood parameters TLC/ DC/ Hb were performed by the coulter method. In a suspected case of pneumonia, a chest x-ray is done and lumbar puncture (LP) is done in suspected case of meningitis. Blood CS was done via a BACTEC 9050 automation system, Becton Dickinson, Ireland. In which 3ml venous blood was inoculated into BACTEC Ped Plus culture vial under complete aseptic conditions. Then blood was kept in the BACTEC 9050 blood culture instrument within 2 hr of collection and subcultures were done in positive cases to identify the causative organism according to the standard methods. Serum CRP level was measured by the semi-quantitative latex agglutination test (AVITEX CRP kits; Catalog No. OD023; supplied by Omega Diagnostics, UK). Urine routine and CS were sent in case of suspected urinary tract infection (UTI) by supra pubic aspiration. All the samples were sent to the laboratory within a half-hour of the procedure.
The following procedure was done for the estimation of micro-ESR at bedside Resuscitaire of newborns in the NICU. Blood was collected in a pre-heparinized micro hematocrit tube of 75 mm length with an internal diameter of 1.1mm and an external diameter of 1.5mm by heel prick technique. Air is not allowed to interrupt the column of blood to avoid false normal result and one end was sealed using clay wax. The micro hematocrit tube was then fixed vertically on a clay tray near the bedside with the identification of patient and the time of blood collection noted and left undisturbed for one hour. There after the distance from the highest point of the plasma column to the meniscus of the packed red cell column (height of the plasma column) of each tube was measured with a ruler after one hour. micro-ESR level was said to be elevated if the height of the plasma column measured were greater than 15mm/hr for all neonates irrespective of age. 12,13 The clinical details and results of laboratory investigations were recorded in a pre-designed proforma. The management of neonatal sepsis was done as per the neonatal unit protocol.
Box. 1. Risk factors, clinical features and laboratory criteria for neonatal sepsis. 10 Suspected sepsis is define as neonates who fulfill the following minimum three signs and symptoms eg. sclerema, lethargy, apnea, hypotonia, poor cry, poor feeding, respiratory distress, grunting, vomiting, fever, Analyzing the maternal and neonatal risk factors for sepsis, in 33 (44%) babies, PROM was the commonest maternal risk factor whereas prematurity 22 (29.3%) followed by fast breathing 19 (25.3%) were the commonest neonatal risk factors (Table 2).    (Table 3). Shah GS et al. at BPKIHS, Dharan, Nepal described the maternal history of PROM, maternal history of foulsmelling liquor, prematurity, low birth weight and low Apgar score at birth were the strong risk factors for early-onset neonatal sepsis. 1 Similarly, in this study, also maternal PROM (44%) and preterm (29.3%) were the commonest risk factors highlighting its major role for sepsis in babies.
CRP is an inflammatory acute-phase reactant that promotes the healing of the injured tissue. 20 CRP is also a good marker of sepsis with sensitivity and specificity of 77.8% and 66.7% respectively. 21 In Ghaliyah AZ et al study, 4 out of 19 babies with elevated micro-ESR level, 12 (63.2%) has positive CRP whereas in our study all twenty-five (100%) babies with elevated micro-ESR had positive CRP showing the significance of CRP with the raised micro-ESR level in sepsis diagnosis.

CONCLUSIONS
Neonatal Sepsis is the commonest cause of neonatal mortality and morbidity. 15 The bedside micro-ESR level test showed significance in the diagnosis of neonatal sepsis for better management in the NICU. Since this is a study of a single institution with convenient sampling, the outcome cannot be generalized.