Aprosencephaly‐atelencephaly and the aprosencephaly (XK) syndrome

Abstract

We report on a postnatally dead, postterm male infant with aprosencephaly and the oculofacial manifestations usually seen in the most severe form of alobar holoprosencephaly -- namely cyclopia and absence of derivatives of the frontonasal process; in addition the infant had the radius aplasia field defect bilaterally, a high VSD, mobile cecum, and penile hypospadias with cryptorchidism. The same syndrome was reported recently by Garcia and Duncan [2]; however, in that case the brain defect was designated "atelencephaly." Since atelencephaly is a less severe form of aprosencephaly we chose to designate the condition in these two patients as "the aprosencephaly (XK) syndrome." Atelencephaly and aprosencephaly may occur also as a single and sporadic malformation. The cause of the aprosencephaly (XK) syndrome is unknown.

Severe brain and limb defects with possible autosomal recessive inheritance: A series of six cases and review of the literature

“…Since the first description of XK aprosencephaly, this syndrome has been reported rarely [Garcia and Duncan, 1977;Lurie et al, 1979Lurie et al, , 1980Martin and Carey, 1982;Towfighi et al, 1987;Kim et al, 1990;Goldsmith et al, 1993]. Bearing in mind the patients reported so far, craniofacial malformations, abnormal genitalia, and limb abnormalities appear to be hallmarks of the XK aprosencephaly syndrome.…”

“…In females, the recognition of genital abnormalities may be more difficult. Abnormalities of the upper limbs may range from hypoplastic thumbs to absent radial ray; they have been found in all but 2 reported cases [Garcia and Duncan, 1977;Lurie et al, 1979Lurie et al, , 1980Martin and Carey, 1982;Towfighi et al, 1987;Kim et al, 1990;Goldsmith et al, 1993;Harris et al, 1994]. Congenital heart disease and anorectal malformations are less constant, even though they may be part of this syndrome.…”

“…The absence of the upper lip, superior maxillary, and nose, combined with a failure in the closure of that area, could be considered a neural tube defect. On the other hand, it might also be considered as a forme fruste of XK aprosencephaly [Garcia and Duncan, 1977;Lurie et al, 1979]. Case 2 had an absence of face and head, including the skull and seems to be a neural tube defect; the cranial abnormalities of this fetus are similar to the manifestations of aprosopia in early embryos.…”

“…In connection with this, Garcia and Duncan [1977] reported on an infant with atelencephalic microcephaly, hypoplastic thumbs, and abnormal genitalia. Two years later, Lurie et al [1979] published a similar case and proposed to call this condition the XK aprosencephaly syndrome. All these reports but one concerned sporadic cases [Adkins and Kaveggia, 1979]; however, Townes et al [1988] reported the coexistence of anencephaly and aprosencephaly within a sibship, thus suggesting that XK aprosencephaly might be an autosomal recessive condition.…”

Prenatal evaluation of atelencephaly

“…It can be differentiated from anencephaly by the presence of a skull and an intact scalp [3]. Atelencephaly is considered largely fatal; however, one case of prolonged survival in a 13-monthold has been documented in the literature [4].…”