A poorly functioning pituitary gland may also cause a lack of thyroid hormone, leading to central hypothyroidism. Thyroid hormone is critical for growth and brain development, especially during the first few weeks to months of life. Children with untreated hypothyroidism are at high risk of mental retardation; thus, early detection is crucial. Central hypothyroidism can be diagnosed by a low or normal thyroid-stimulating hormone (TSH) in the presence of a low level of free T4. Free T-4 should be checked annually for at least four years.Cortisol is made in times of stress. Approximately one-quarter of patients with ONH have adrenal insufficiency, meaning they do not produce enough cortisol on a daily basis or in stressful situations.Imbalances in sex hormone may result in a delay in sexual development (puberty) or precocious puberty. Sex hormones may be tested from birth to 6 months of age (during a mini-puberty). Hyperprolactinemia (an excess of prolactin) often occurs in conjunction with ONH and indicates either dysfunction of the hypothalamus or a disconnect between the hypothalamus and pituitary gland. Hyperprolactinemia often correlates with development of obesity in children with ONH.The posterior pituitary gland produces anti-diuretic hormone (ADH), which controls outflow of water from the body by urine. ADH deficiency, also known as diabetes insipidus (DI), results in dehydration and high sodium levels in the body from excessive urination. Testing for DI involves blood and urine testing, including water deprivation tests, to determine ADH creation levels by the body.
DI may be treated with a medication called desmopressin acetate (DDAVP).Oxytocin is also produced in the posterior pituitary gland. Though best known for its role in childbirth and lactation, oxytocin has also been found to have a role in human bonding, increase in trust, and decrease in fear. Hypothalamic dysfunction may also result in problems with feeding, sleep, and body temperature regulation. Feeding behaviors in children with ONH often include hyperphagia (overeating), resulting in obesity; or hypophagia (reduced food intake) with or without weight loss. Children also frequently experience aversion to specific textures of food. Disturbance of circadian sleep rhythm, resulting in abnormal sleep-wake cycles, is noted in one-third of children with ONH. This disturbance could result in behavioral problems and disruption of family life. Development
More than 70% of children with ONH experience developmental delay, ranging from isolated focal defects to delay in all areas of development (global delay). Motor delay is most common (75%) and communication delay is least common (44%). Predictors of significantly delayed development include hypoplasia or agenesis of the corpus callosum and hypothyroidism. The absence of the septum pellucidum does not predict developmental delay. Delays may occur in unilateral (39%) as well as bilateral (78%) cases. Cause
Genetic risks
Mutations of genes involved in transcription regulation, chromatin remodelling, α-dystroglycan glycosylation, cytoskeleton and scaffolding protein, RNA splicing, and the MAP kinase signalling pathway are currently known to cause ONH.