Congenital adenohypophysis aplasia

Abstract

Case A 3190-gram infant was born at 39 weeks gestation to a 28-year-old gravida 3 para 2 mother after an uncomplicated pregnancy. The baby was lethargic at birth and required stimulation. A very small phallus was noted. Because of lethargy a serum glucose level was obtained which was 20 mg%. The patient was given a bolus of 4 ml kg À1 D10 glucose-saline solution. However, to maintain normal serum glucose levels, the baby was maintained on 1.5 ml/kg/h of D10. An abdominal sonogram ( Figure 1) and cranial magnetic resonance imaging (Figures 2 and 3) were obtained. Denouement and discussionThe abdominal sonogram failed to demonstrate an adrenal gland on either side. Although criteria are better established for congenital adrenal hyperplasia, measurable adrenal glands should be present in the normal neonate. In particular a right adrenal gland is identified in essentially 100% of newborns.1 The absence of identifiable adrenal glands suggests either deficient adrenocorticotropin hormone or adrenal hypoplasia congenita (AHC). The latter is a rare condition. It occurs in two histological forms: the miniature adult form and the cyomegalic form.2 The miniature adult variety AHC has a tiny gland with a permanent cortex making up almost the entirety of the gland. This condition can be inherited as an autosomal recessive condition or be sporadic.3 The cytomegalic variety of AHC is an X-linked recessive condition and is associated with the IMAGe syndrome. X-linked AHC is due to mutations in the DAX-l and associated with hypogonadotropic hypogonadism. 4 IMAGe syndrome is a presumed autosomal recessive condition consisting of intrauterine growth retardation, metaphyseal dysplasia, adrenal hypoplasia congenita, and genital abnormalities. The pathology of the adrenal glands in IMAGe syndrome and X-linked AHC is similar. A definitive adrenal cortex is not present and the cortical cells that are present are markedly enlarged eosinophilic irregular cells with nuclear inclusions.3 In this patient the cortisol level was found to be low; 1.5 mg 100 ml À1 (normal 4.3 to 22.4), but the ACTH level was 5 pg ml À1 (normal 10 to 60), and the thyroxine levels and growth hormone levels were also slightly depressed. The cranial magnetic resonance imaging demonstrated absence of the anterior pituitary with the bright neurohypophysis seen posterior to the optic nerves.

Neonatal Hypopituitarism: Approaches to Diagnosis and Treatment

“…Values under 1.5 cm at gestational age 30 weeks, 2 cm at 34 weeks and under 2.5 cm in term infants are defined as micropenis (30). Optic nerve hypoplasia or corpus callosum agenesis-related nystagmus may be observed in infants (31,32). Polyhydramniosis, polyuria, weight loss, anxiety, demand for water instead of formula, signs and symptoms of dehydration and hypernatremia are observed in cases of diabetes insipidus (33).…”

Neonatal Hypopituitarism: Diagnosis and Treatment Approaches

“…Values below 1.5 cm at thirty weeks old, 2 cm at 34 weeks old and below 2.5 cm in term infants are considered as micropenis (30). Optic nerve hypoplasia or corpus callosum agenesis related nystagmus may be observed in infants (31,32). Polyhydramniosis, polyuria, weight loss, anxiety, water demand instead of formula, dehydration findings and hypernatremia are observed in diabetes insipidus cases (33 (21).…”