ORIGINAL

Niger J Paed 2012; 39 (4):159 - 163

Israel-Aina YT

Omoigberale AI

Risk factors for neonatal jaundice in

babies presenting at the University

of Benin Teaching Hospital, Benin

City

DOI:http://dx.doi.org/10.4314/njp.v39i4.2

Accepted: 13th March 2012

Abstract Background: Jaundice is

the yellowish discoloration of the

skin, sclera and mucous membranes

resulting from deposition of

bilirubin. Neonatal jaundice is a

leading cause of neonatal admis-

sions in the first week of life and

risk factors such as sepsis, prema-

turity, glucose-6-phosphate dehy-

drogenase enzyme deficiencies, use

of native herbs and contact with

naphthalene balls contaminated

clothes have been identified for

neonatal jaundice.

ered in UBTH (in-born babies),

while 202 (42.8%) of the babies

were born before arrival (out-born

babies) in UBTH. The Male: Fe-

male ratio was 1.02:1. The mean

age at presentation with jaundice

was 3.43 ± 3.76 days of life. Out-

born babies tended to present at an

older age (6.08 ± 5.19 days) than in

-born babies (2.47 ± 2.48 days).

The mean serum bilirubin value in

out-born babies (14.00 ± 4.58 mg/

dL) was significantly higher than

that observed among the in-born

babies (9.35 ± 4.38 mg/dL: p =

0.000). The risk factors identified

were use of mentholatum, naphtha-

lene balls and native herbs in

40.0%, 16.7% and 7.0% respec-

tively. ABO incompatibility was

found in 7.6% of babies. No risk

factor was identified in 36.3% of

the babies. The case fatality rate in

this study was relatively high par-

ticularly in association with sepsis,

prematurity and asphyxia. Mortality

was higher in out-born babies than

in in-born babies (p= 0.00).

Israel-Aina YT⁽

Omoigberale AI

)

Department of Child Health,

University of Benin Teaching

Hospital,

Benin City, Edo State,

Nigeria

Objective: To determine the risk

factors for neonatal jaundice at Uni-

versity of Benin Teaching Hospital,

Benin City.

Methods: This retrospective study

was conducted at the Special Care

Baby Unit of the University of Be-

nin Teaching Hospital, Benin City.

Case notes of babies admitted from

January 2006 to December 2008

were retrieved and information on

biodata, gestational age, anthro-

pometric values, potential risk fac-

tors, level of serum bilirubin at

presentation and discharge, mode of

treatment and outcome were ex-

tracted.

Conclusion: Early presentation of

babies and adequate management of

sepsis and prematurity will reduce

mortality associated with neonatal

jaundice.

Results: Of the 1784 babies admit-

ted during the period, 472 (26.5%)

were admitted for neonatal jaudice.

Fifty seven percent of the babies

with neonatal jaundice were deliv-

Key words: In-born, jaundice, out-

born, risk, sepsis.

Introduction

duced red blood cell lifespan while accumulation results

from a relatively low rate of conjugation of bilirubin by

the liver. The resultant effect of this is an increase in

unconjugated, non po₃la_-₄r lipid soluble bilirubin that is

deposited in the skin. Excessive rise in the level of

unconjugated bilirubin is of great clinical concern be-

cause this form of bilirubin is neurotoxic and can cause

death in the newborn period as well as lifelong neuro-

logical sequellae. Conjugated bilirubin is not neuroto₃_-x₆ic,

but it may signify a serious disorder in the newborn.

Jaundice is the yellowish discoloration of the skin,

sclera and mu_-₂cous membranes resulting from deposition

1

of bilirubin. Neonatal hyperbilirubinaemia is defined

as serum bilirubin greater than 5mg/dL and it occurs

when the rate o_-f₃ bilirubin production exceeds excretion

1

from the body. Bilirubin production in the newborn is

two to three times higher per kilogram body weight than

in adults. This is due to the high red cell mass and re-

1

60

Neonatal jaundice is a very common clinical condition

and over 60% of term newborns and 80% of preterm

neon₁_,a₅t_-₇es will develop jaundice in the first week of

computed and frequency tables generated as required.

P values less than 0.05 were considered significant.

life.

Neonatal jaundice is a leading cause of neonatal

admissions in the first week of life and constitutes an

5

-7

important cause of neonatal morbidity and mortality.

Results

In developed countries, risk factors include haemolytic

diseases (Rhesus isoimmunisation and ABO haemolytic

disease), prematurity, sepsis, and enzyme deficiencies

Of the 1784 babies admitted into SCBU from January

2006 to December 2008, 472 (26.5%) were admitted for

neonatal jaundice. Two hundred and seventy (57.2%) of

the babies with neonatal jaundice were delivered in

UBTH (Inborn babies), while 202 (42.8%) of the babies

were born before arrival (out born babies) in UBTH.

(

Uridyl d_-i₇phosphate glucoronyl transferase enzyme defi-

1

ciency). In Nigeria, neonatal sepsis, prematurity, glu-

cose-6-phosphate dehydrogenase enzyme deficiency,

use of native herbs and contact with naphthalene balls

contaminated clothes ha_-₁v₁e been identified as risk factors

7

for neonatal jaundice. The present study was under-

Fifty seven percent (270/472) of the babies with neona-

tal jaundice were males while 202/472 (42.8%) were

females. The gender representation of the study popula-

tion was comparable (Male: female ratio was 1.02:1, p =

taken to determine the prevalent risk factors for neonatal

jaundice at University of Benin Teaching Hospital, Be-

nin City.

0

.67).

Two hundred and ninety (61.4%) of the 472 mothers

booked for antenatal care in pregnancy while 182/472

Subjects and methods

(

38.6%) did not. Mothers of the in-born subjects were

The study population consisted of babies admitted into

the special care baby unit (SCBU) of the University of

Benin Teaching Hospital from January 2006 to Decem-

ber 2008. The special care baby unit of the hospital is a

more likely to book in pregnancy than mothers of the

out-born subjects (49 % Vs 13%, χ = 147.81, p = 0.000:

95% CI = 2.73 to 4.78)

2

5

0-bed ward. It provides care to babies born in the hos-

Table 1 shows the age distribution of the study popula-

tion. The mean gestational age of the study population

was 37.36 ±2 .80 weeks. There was no significant differ-

ence in the gestational age of the inborn (37.25±3.16

weeks) and out-born (37.62±1.66 weeks) babies.

(t= -1.51, p =0.13, 95% C.I. = -0.85 to 0.11)

The mean age at presentation with jaundice was 3.43 ±

3.76 days of life. Out-born babies tended to present at an

older age (6.08 ± 5.19 days) than in-born babies (2.47 ±

2.48 days). (t = -10.01, p = 0.00, 95% C.I. =-4.32 to -

pital and others referred from elsewhere in Edo State

and neighbouring States. Ethical approval was given by

the Ethics Committee of the hospital. The babies’ case

notes were retrieved from the medical records of the

hospital and information on biodata, demographic char-

acteristics, gestational age, anthropometric measure-

ments, potential risk factors, level of serum bilirubin at

presentation and discharge, mode of treatment and out-

come were extracted.

2

.90). This was significant.

Analysis of data was done using the Statistical Package

for Social Sciences (SPSS) version 16.0 (SPSS Inc. Chi-

cago IL). Measures of statistical location like mean and

standard deviation of continuous variables were

The mean maternal age of mothers was 30.44 ± 5.63

years. It was similar between mothers of the in-born

babies (30.52 ± 5.65 years) and of out-born babies

(

30.26 ± 5.62 years). (t = 0.50, p = 0.62, 95% C.I. = –

0

.77 to 1.29).

Table 1: Age distribution of the study population and their mothers.

Characteristics

Age

Inborn

Outborn

Study

Population

mean±SD

t-test

p-value

mean±SD

Presentation (days)

Maternal age (years)

Gestational age (weeks) 37.25±3.16

2.47±2.48

30.52±5.65

6.08±5.19

30.26±5.62

37.62±1.66

3.43±3.76

30.44±5.63

37.36±2.80

-10.01

0.50

-1.51

0.00

0.62

0.13

Anthropometric values

comparable to that of referred babies (p = 0.86 and 0.74

respectively). The length of referred babies (51.85±5.06)

was however significantly higher than that for in-born

babies (49.40±5.37, p = 0.00, t=-5.03, 95% C.I. = -

3.41to-1.49).

Anthropometric values of in-born and referred babies

are shown in table 2. The birth weight of the study popu-

lation ranged from 500g to 4500g. The mean weight and

occipito-frontal circumference of in-born babies was

1

61

Table 2: Anthropometric measurements of the study population

Characteristics

Inborn

Outborn

Study

Population

mean±SD

t-test

p-value

mean±SD

Birth weight (gm) 2,980±700

2,990±510

51.85±5.06

33.88±8.38

2,990±640

49.95±5.49

33.91±4.64

-0.17

-5.03

-0.33

0.86

0.00

0.74

Length (cm)

OFC (cm)

49.40±5.37

33.70±2.59

Level of serum bilirubin

Table 4: Diagnoses associated with neonatal jaundice in

the study population

Serum bilirubin of study subjects at admission ranged

from 4 to 25 mg/dL with a mean of 9.95±4.59 mg/dL.

The mean SB value in out-born babies (14.00 ± 4.58

mg/dL) was significantly higher than that observed

amongst the in-born babies (9.35 ± 4.38 mg/dL: p =

Diagnoses

n (%)

Sepsis

Prematurity

Asphyxia

ABO incompatibility

Multiple diagnoses

Total

212 (45.0)

94 (19.9)

36 (7.6)

472 (100)

0

.00) – Table 3.

The mean SB for the out-born babies who were dis-

charged (7.09±3.63mg/dL) was significantly higher than

the mean SB of the in-born babies (5.85±2.23mg/dL) (t=

Treatment and outcome

-5.22, p = 0.00, 95% C.I. = -1.78 to -0.71).

One hundred and sixty six (35%) of the study population

were treated with exchange blood transfusion. Photo-

therapy alone was the mode of treatment in 212(45%)

patients while 94 (20%) had no specific treatment di-

rected at jaundice. Three hundred and seventy one

Table 3: Serum bilirubin measurements of the study popula-

tion

Characteristics

Inborn

9.35±4.38 14.00±4.58 -11.19

5.85±2.23 7.09±3.63 -5.22

Out-born

t-test p-value

(

78.6%) babies were discharged home: 41 (8.7%) dis-

Laboratory SB (mg/dl)

SB values at discharge

0.00

charged against medical advice while 60 (12.7%) died.

Of the 60 mortality, 40 (21.5%) were from the out-born

section while 20 (8.2%) were in-born babies. Thus, mor-

(

mg/dl)

SB values at DAMA

mg/dl)

(

13.74±4.77 14.80±1.67 -3.38 0.00

tality was significantly higher among out-born babies

2

than inborn babies.

(χ =14.61, p = 0.00, 95% C.I. =

Clinical presentation of babies

0.17 to 0.60) The mean gestational age (23.00±0.10

weeks) and birth weight (500±100g) of babies that died

in the in-born section was significantly lower than the

mean gestational age (37.00±1.16 weeks) and birth

weight (2,500±580g) of out-born subjects. (p=0.00 in

both cases). In the out-born section, the mean age of

presentation of the babies that died was 8.00±4.62 days

and this was higher than the mean age of presentation of

in-born subjects (1.00±1.99day, t= -6.46, p=0.00, 95%

C.I. = -9.2 to -4.8).

Common accompanying complaints were fever and poor

suck in 253 (53.6%) and 168 (35.7%) of cases. Twenty

seven (5.7%) babies presented with lethargy and 24

(

5.1%) presented with jaundice and had no other com-

plaints.

Risk factors

Seventy nine (16.7%) mothers, all referred, admitted to

storing the babies’ clothes with naphthalene balls. Men-

tholatum was used for cord care in 189(40.0%) of the

study population while native herbs were used in 33

Sepsis accounted for 70% (42/60) of deaths. Twelve

deaths occurred in preterm babies while six deaths were

associated with perinatal asphyxia. The mean SB

(16.15±0.75mg/dL) of babies that died in the out-born

section was higher than the mean SB (11.00±1.00mg/

dL) of babies that died in the inborn section. (t= -22.38,

p= 0.00, 95% C.I. = -5.61 to -4.77)

(

7.0%) cases. There was no identifiable risk factor in

1

71 (36.3%) of subjects. The diagnoses of babies in this

study were sepsis, prematurity, perinatal asphyxia and

ABO incompatibility. The diagnosis of sepsis was made

in 212 (45.0%) babies. Other details with regard to diag-

noses are as shown in table 4.

1

62

Table 5: Characteristics of fatal cases.

2

Characteristics

Inborn

Out-born

40 (21.5)

t-test

χ

p-value

Case fatality n (%)

20 (8.2)

-

14.61 0.00

Mean serum bilirubin (mg/dl) 11.00±1.00 16.15±0.75

-22.38

-53.65

-6.46

-

0.00

Gestational age (weeks)

Age at presentation (days)

23.00±0.10 37.00±1.16

1.00±1.99 8.00±4.62

times more prone to developing neonatal jaundice than

2

G-6-PD deficient infants. The use of naphthalene balls

Discussion

in this study (16.7%) is higher than what was found in

Abakaliki where 6.9% of mothers of the out-born ba-

7

Slightly more than a quarter of newborns in the current

report presented with jaundice. The prevalence of jaun-

bies used naphthalene balls in storing their baby’s

clothes. Though the use of naphthalene balls was found

in some babies in this study, the G-6-PD enzyme assay

was not done for any of the babies in this study, as neo-

natal screening for the enzyme deficiency is not rou-

tinely carried out in our locale. None of the mothers of

in-born neonates agreed to the use of naphthalene balls

for storage of babies’ clothes. Mothers of in-born neo-

nates are more likely to attend antenatal care and may

have been counseled on recognition of jaundice and

avoidance of possible agents that can cause haemolysis

in the newborn. This study found that significant propor-

tions (49%) of the mothers of the in-born babies were

booked compared with mothers of the out-born babies

(13%). Th₇is finding was similar to what was found in

Abakaliki.

7

dice in₁ this study is lower than figures of 35% and

1

4

5.6% previously reported from other centres in Nige-

ria. Sepsis and prematurity were major diagnosis identi-

fied in this study occurring in 45% and 20% of the study

population. Other workers within and outside Nigeria

have also observed neonata₇_,l₉j_,a₁₀u_,n₁₂dice in association with

these two clinical entities.

The case fatality rate herein reported is relatively high

particularly in association with sepsis, prematurity and

asphyxia. This is similar to the findings of Owa et al in

Ile Ife Nigeria, in which septicaemia was associated with

high mean SB level and the highest mortality. Sepsis is a

cause of jaundice in the newborn period. Babies who

have sepsis are likely to develop high levels of bilirubin

from incr₂e_-₃a_,s₆ed haemolysis and defective conjugation of

The mean age of presentation with jaundice was three

days. The out-born subjects presented significantly late

(six days) than the in-born subjects (two days). The rea-

son for early presentation of in-born babies may be that

jaundice was recognized by the health workers before

discharge from the hospital. Also, the mean serum

bilirubin was higher in the out-born subjects than in in-

born subjects possibly because the out-born subjects

presented late compared with in-born subjects. These

findings are similar to study from Abakaliki.

bilirubin.

Premature babies are prone to hyper-

bilirubinaemia because of immaturity of their liver en-

zymes resulting in defective conjugation of bilirubin and

1

-3,6

increased haemolysis from reduced red cell life span.

Preterm babies are also prone to other clinic₁a_-l₃ conditions

like sepsis that may affect outcome in them.

In 7.6% of the study population, ABO incompatibility

was found to be the sole risk factor while multiple diag-

noses were made in another 7.6% of the study popula-

tion. ABO incompatibility is the most common form of

haemolytic disease in the newborn period. This clinical

entity is diagnosed in the presence of a positive direct

coombs test, reticulocytosis and microspherocytes in a

In this study, there was recourse to exchange blood

transfusion in 35% of subjects and phototherapy in 45%.

The EBT rate in this study is higher than previously

documented rate in Abakaliki and Ile-Ife, Nigeria.

1

baby with haemolysis. However, only half of those with

positive direct coombs test are likely to have significant

Seventy eight percent of the study population was dis-

charged home following treatment. Forty one (8.7%)

discharged against medical advice while 12.7% died.

Mortality was higher amongst the out-born babies than

amongst the in-born babies. This possibly is due to the

fact that the out-born babies presented late and had

higher serum bilirubin than the in-born babies.

haemolysis while some infants with ne_,₂gative direct

1

coombs test have increased haemolysis. Hence, the

development of hyperbilirubinaemia in babies with set-

tings for ABO incompatibility depends on the conjugat-

ing ability of the babies. The use of naphthalene balls in

storage of baby’s clothes was found in 16.7% of the

study population and only in mothers of out-born sub-

jects. Naphthalene and mentholatum are recognized

agents ₃that cause haemolysis in G-6-PD deficient pa-

1

tients. Glucose-6-phosphate dehydrogenase enzyme

deficiency is the most common red cell enzy_-₃mopathy

1

that causes neonatal haemolysis and jaundice. It is an

Conclusion

X- linked recessive disorder that affects males; however,

deficient females may also present with haemolysis and

jaundice. Babies who are G-6-PD deficient are three

The diagnoses identified in babies with jaundice in this

study were sepsis, prematurity and ABO incompatibil-

1

63

ity. Out-born newborns with jaundice presented to the

hospitals late and had significantly higher serum

bilirubin at presentation. Mortality was also higher in

out-born babies than in-born babies. Early presentation

of affected babies will significantly reduce mortality.

Expectant mothers should also be encouraged to book

their pregnancies and to deliver in standard health facili-

ties. Adequate treatment of sepsis will significantly re-

duce mortality in these babies.

Conflict of interest : None

Funding : None

Acknowledgement

Limitation of study

The authors appreciate the support of unit doctors during

the period of data collection.

This is a retrospective study; hence it was difficult to

establish the contribution of other known risk factors

like G-6-PD deficiency since routine screening of this

enzyme deficiency is not done in the centre.

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