A Cross-Sectional Prospective Study of Cutaneous Lesions in Newborn

Background. Cutaneous alterations are common in neonates. The majority of lesions are physiological, transient, or self-limited and require no therapy. Although much has been reported on the various disorders peculiar to the skin of infant, very little is known about variations and activity of the skin in neonates. Objective. To study the various pattern of skin lesions in newborn and to estimate the prevalence of physiological and pathological skin lesions in newborn. Methods. A total of 1000 newborns were examined in a hospital-based, cross-sectional prospective study in the period of November 2007 to May 2009. Results. The physiological skin changes observed in order of frequency were sebaceous gland hyperplasia (89.4%), Epstein pearls (89.1%), Mongolian spot (84.7%), knuckle pigmentation (57.9%), linea nigra (44.5%), hypertrichosis (35.3%), miniature puberty (13.3%), acrocyanosis (30.9%), physiological scaling (10.8%), and vernix caseosa (7.7%). Of the transient noninfective conditions, erythema toxicum neonatorum was seen in 23.2% newborns and miliaria crystallina in 3% newborns. The birthmarks in descending order of frequency were salmon patch (20.7%), congenital melanocytic nevi (1.9%), and café-au-lait macule (1.3%). Cutaneous signs of spinal dysraphism were sacral dimple (12.8%), meningomyelocele (0.5%), acrochordons (0.1%), and dermoid cyst (0.1%). Conclusion. The physiological and transient skin lesions are common in newborns particularly sebaceous gland hyperplasia, Epstein pearls, Mongolian spots, and erythema toxicum neonatorum. It is important to differentiate them from other more serious skin conditions to avoid unnecessary therapeutic interventions.


Introduction
The newborn or neonatal period is the first 4 weeks of extrauterine life. The skin of the neonate differs from adult in several ways. The thickness of newborn skin is 40% to 60% of that of adult skin. It has weaker intercellular attachment and produces lesser amount of sweat.
A host of aberrations varying from physiological (Mongolian spot) and transient (erythema toxicum neonatorum) to grossly pathological (neonatal lupus erythematosus) are seen in the skin of neonates.
Majority of the neonatal cutaneous lesions are physiological and transient requiring no therapy. However, these cause concern not only to the parents but also to the physicians who are unfamiliar with these skin changes in newborn.
It is necessary to differentiate between benign and clinically significant skin lesions in newborn. Pigmented lesions at birth, such as Mongolian spots, are benign and almost always disappear by few years, whereas congenital melanocytic nevi are clinically significant because of future risk of malignant melanoma.
Therefore it is important to be aware of the innocent transient skin lesions in newborn and differentiate these from other serious conditions which will help avoid unnecessary therapy to the neonates and the parents can be assured of good prognosis of these skin manifestations.

ISRN Dermatology
The neonatal skin changes show a wide geographic and ethnic variation. Some skin lesions are common in darker skin races and vice versa. It is important to know the pattern of dermatoses prevalent among Indian children at the neonatal period. However, studies on neonatal dermatoses, conducted in India, are limited. Hence, this study has been planned to know the prevalence of different cutaneous lesions among newborns in India.

Exclusion Criteria.
Neonates kept in neonatal intensive care unit were excluded from the study, as repeated handling of the babies can increase the chances of infection and sepsis.

2.2.3.
Procedure. Detailed history was recorded especially age of the mother, parity of mother, history of consanguinity, mode of delivery, and history of maternal illness during pregnancy. The neonates were examined thoroughly in daylight with accurate definition of morphology of skin lesions and findings were recorded. The sex, birth weight and age at the time of examination were noted in each case. In all instances, diagnosis of disorder was based on clinical impression. Skin biopsy was done in one case.

Statistical Analysis.
The observations pertaining to parameters under study among the newborn babies are expressed in percentage.
The relationship between skin lesions and various maternal-neonatal aspects is calculated using Z-test, with ≤ 0.05 considered statistically significant.

Results
Among 1000 newborns, 543 (54.3%) were males and 457 (45.7%) were females. Term newborns were 891 (89%), preterm were 93 (9.3%), and postterm were 16     <20 yrs of age, and 30 (3.0%) were in age group >30-35 yrs. The relationship of skin lesions with maternal and neonatal factors is given in Table 1. The frequency of skin lesions in newborns is given in Table 2. Of all the cutaneous lesions in the newborn, physiological skin lesions were more common in 5911 (59.       There was no statistically significant difference in distribution of physiological skin lesions among males and females except for few cutaneous manifestations like vernix caseosa, physiological scaling, Epstein pearls, hypertrichosis, linea nigra, genital pigmentation, pigmentation of pinna, knuckle pigmentation, Mongolian spot, and acrocyanosis. As shown in Table 3, vernix caseosa ( Figure 1) was seen commonly in females compared to males with a statistically significant ( < 0.05) difference, whereas all other physiological skin lesions were seen commonly in males.

Discussion
The appreciation of normal phenomena and their differentiation from the more significant cutaneous disorders of the neonate is critical. The prevalence of dermatoses among newborns has been documented in various studies conducted in different racial groups (Table 6).
Sebaceous gland hyperplasia (SGH), Epstein pearls (EP), Mongolian spot (MS), and erythema toxicum neonatorum (ETN) are the skin lesions which were commonly seen in the study. The prevalence of skin lesions is comparable to that of the previous study results [1][2][3][4] except sebaceous gland hyperplasia which has shown the highest prevalence (89.4%) in the present study. It was seen commonly in term neonates 789 (88.25%). Sebum secretion rates are high in neonates compared with preadolescent children. It is assumed that this sebaceous gland activity reflects the stimulation by placentally transferred maternal androgen, particularly by dehydroepiandrosterone [5].
Mongolian spot has been shown to be a good example of interracial difference. The prevalence of Mongolian spot has been as high as 80 to 90% in Asians [6,7], and it has been as low as 3 to 10% in Caucasians [4,8]. In Indians, the prevalence varies from 72 to 89% [6,[9][10][11]. In the present study, 84.7% of newborns had this birthmark, similar to that of the study conducted by Dash et al. [6].
Epstein pearls were seen in 891 (89.1%) neonates, with the commonest site of location being midline of palate. They occur commonly in 64-89% of normal neonates and are common in Caucasian infants. The similar prevalence rate has been noted in an Indian study conducted by Nanda et al. [9].
Erythema toxicum neonatorum was seen in 23.2% of neonates, similar to previous study conducted in India [9][10][11]. It was seen within 48 hrs of life, most commonly in full-term neonates. The prevalence varies among different racial groups [1,3,4,7,12]. It is most commonly seen in Caucasians (37.8%) [2], than colored population. However, in a recent study conducted in Jordan, erythema toxicum neonatorum showed the highest prevalence rate of 68% in black-skinned population [13], which may suggest reasons other than racial factors. Erythema toxicum neonatorum has to be distinguished from other infective and noninfective pustular disorders in neonates [14].
Among epidermal pigmentary changes, ( Figure 5) linea nigra (44.5%) and knuckle pigmentation (57.9%) were most commonly seen. In a recent study by Pruksachatkunakom et al. [2], linea nigra was seen in 51.8% blacks and 5.0% Caucasians. It has been postulated to be a response to the maternal and placental hormones that enter the total circulation. Among these hormones, estrogen and progesterone have been  reported to exert a melanocytic stimulating effect which also causes darkening of linea alba in pregnant women [2].
Physiological scaling, the most common finding, was seen in 105 (10.5%) neonates in the present study, compared to a study of Australian neonates, where the frequency of occurrence was 65% [11]. It was seen in 97 (92.38%) fullterm neonates, 5 (4.76%) preterm, and 3 (2.88%) postterm neonates. Preterm infants showed desquamation in the present study, compared to other studies [1,6], where desquamation was not seen in preterm neonates. The variation in prevalence is mainly because the duration of observation in our study was less than 4 weeks, the time when permeability barrier of preterm neonate undergoes maturation. However, in other studies the duration of observation was within 48 hrs of birth and premature infants do not show desquamation until 2-3 weeks of life. Vernix caseosa was seen in 7.7% of neonates. It was seen most commonly on 1st day of life. The prevalence of vernix caseosa has not been reported in previous studies.
Salmon patch was the most common vascular birthmark seen (20.7%). The prevalence of salmon patch varies in different studies. It is 22.3% in a Japanese study [7], 28.4% in an Indian study [9], 27.8% in a Taiwanese study [8], 18.78% in Jewish, and 19.97% in Arab neonates [15]. The most common site of occurrence in the present study was eyelids (90.82%). Female preponderances in vascular birthmarks were noted in Japanese survey [7]. In this study, males had higher prevalence (10.6%) than females (10.1%). However, this difference was not statistically significant ( = 0.6231).
The surveys of congenital melanocytic nevi in newborns showed a prevalence of 0.4 to 15.6%, with the highest percentage among nonwhitish babies [2]. An interesting study which adopted a comparative approach between Arabs and Jews in Israel, conducted by Kahana et al. [15], found that Arabs had greater number of melanocytic brown lesions (Mongolian spots, congenital melanocytic nevi, and café-au-lait macule) than Jews descending from European ancestry, but Jews descending from Asia and Africa had almost equal frequency of these melanocytic brown lesions as in Arabs. Congenital melanocytic nevi were seen in 19 (1.9%) newborns. The size of the nevi is important; nevi larger than 20 mm are considered to be giant type and are one of the precursors of melanoma [16]. Café-au-lait macules were seen in 13 (1.3%) neonates. One newborn had multiple café-au-lait macules and similar lesions were also seen in her mother and sibling. The prevalence of café-au-lait macule among Arabs is 0.48% and Jewish neonates is 0.11% [15].
Cutaneous signs of spinal dysraphism were seen in 135 (13.5%) neonates. Sacral dimple was seen in 128 (12.8%) neonates. The prevalence is higher than that in American neonates (1.4%) [2]. However, further investigations were not done for definitive diagnosis of spinal dysraphism. Meningomyelocele was seen in 5 (0.5%) neonates. None of these neonates showed any signs of neurological deficit except one neonate who was unable to move his limbs.
Vaginal tags and cowlicks hair pattern are two conditions which were not reported in previous observational studies on cutaneous manifestations in newborns. Vaginal tags were seen in 18 (1.8%) newborns. They are normal hymenal characteristic which can be seen in 59% of newborns [17]. Cowlicks hair is a normal frontal hair pattern seen in 7% of individuals and may have genetic contributions [18].
Anhidrotic ectodermal dysplasia was seen in one neonate who had loss of eyebrows, eyelashes with periorbital pigmentation. Skin biopsy done from hypothenar eminence of palm showed absent sweat glands [19].

Conclusion
Sebaceous gland hyperplasia, Epstein pearls, Mongolian spot, and erythema toxicum neonatorum were the commonest physiological and transient skin lesions seen in the study.
The study of newborn skin provides information about normal variants occurring in neonatal period. It is important to be aware of the fact that most of the skin lesions in the newborn are transient and require no therapy.
Therefore, it is necessary for those who provide neonatal care to differentiate physiological skin lesions from other more serious skin conditions which will help avoid unnecessary therapy to neonates. The parents can be assured of good prognosis of these skin manifestations.