Discussion
The collodion baby indicates a phenotype that precedes the underlying disease entity. It is characterized by a yellow, shiny, tight parchment-like membrane that covers the body. As collodion babies look very much alike at birth, the outcome is difficult to predict. The initial severity of phenotype and time to membrane shedding may be indicative of the severity of the underlying condition. When the membrane peels off, underlying skin disorders may usually be revealed. It is considered that about 10% of all collodion babies heal spontaneously within the first few weeks and develop normal underlying skin.4,5 This condition is called “self-healing” collodion baby or “lamellar exfoliation of the newborn.”
The benign and self-limited clinical course of self-healing collodion baby distinguishes itself from lamellar ichthyosis. The cause of self-healing collodion phenotype is not fully understood, and it is considered as dynamic phenotype, which refers to the possible clinical evolution of the disease over time.6 Thus, using the term “self-improving collodion ichthyosis” as more appropriate is suggested by some authors as many of the collodion baby patients showed mild signs of ichthyosis when re-examined at 2–37 years of age.7
Recently, mutations in the TGM1 gene, encoding epidermal transglutaminase 1, which play an important role in lamellar ichthyosis and nonbullous congenital ichthyosiform erythroderma, have been linked to self-healing collodion phenotype.8 Also, mutations inthe ALOX12B gene, encoding 12 (R) - lipoxygenase have been described to be relevant for SHCB.7,8
The other diagnoses that need to be considered ii CB are the three types of autosomal recessive congenital ichthyoses: non-bullous congenital erythroderma, lamellar ichthyosis, and harlequin ichthyosis.2,3 Patients with lamellar ichthyosis have large, dark, platelike scales involving the entire body surface, ectropion, eclabium, and secondary nail deformity. These patients do not usually improve with age. On the other hand, non-bullous congenital erythroderma is characterized by generalized erythema and fine white scales, mild ectropion, eclabium, hyperkeratotic palms, and soles. Harlequin ichthyosis is the rarest and the most severe form, and it is associated with respiratory and feeding difficulties, severe skin infections, and lethal outcomes in early infancy.Other milder phenotypes include ichthyosis vulgaris and X-linked recessive ichthyosis. Autosomal dominant ichthyosis vulgaris usually manifest between 3 and 12 months of age. X-linked ichthyosis is a genetic disorder caused by a mutation of the enzyme steroid sulfatase involved in the metabolism of cholesterol sulfate. It is presented at birth or early in infancy and affects males exclusively. Rarely, Sjögren Larsson syndrome, Netherton syndrome, Gaucher disease type 2, or some ectodermal dysplasias may be associated with collodion membrane and should be considered if extracutaneous symptoms are present.9
The management of collodion baby remains a challenge. Although the vast majority of collodion babies are born at term, they require special neonatal care as premature babies. Various complications may occur, such as hypernatremic dehydration, hypothermia, skin infections, fissures, conjunctivitis, sepsis, constrictive bands of the extremities resulting in vascular compromise and edema.10,11 Placement of the baby in a temperature-controlled, humidified incubator is essential to reduce transepidermal water loss and prevent skin infections. Also, most of the authors recommended maintaining the neonate in the incubator for at least 4 weeks or until the membrane completely detaches.12,13
It is mandatory to practice all measures for the prevention of hospital infections. The use of intravenous lines and blood sampling should be very restrictive to avoid further skin damage. However, the prophylactic use of antibiotics is not recommended. Ophthalmological management of ectropion is essential for preventing conjunctivitis and keratitis.13 The skincare includes applications of bland emollients, as it was shown that they facilitated skin healing and led to a relatively uncomplicated hospital course. 4
Recent advances in neonatal intensive care have improved the overall prognosis of CB. The outcome depends on the initial assessment and adequate multidisciplinary approach and treatment.