According to abbreviationfinder, HHL stands for posterior pituitary insufficiency. Posterior pituitary insufficiency is characterized by an isolated failure of the hormone secretion of the posterior pituitary or at least by a reduced release of the hormones oxytocin and ADH (antidiuretic hormone) produced in the hypothalamus. Oxytocin plays a special role in the birth process in women and generally has a positive effect on social relationships. ADH is an antidiuretic peptide hormone that is also synthesized in the hypothalamus and released into the bloodstream by the posterior pituitary gland.
What is posterior pituitary insufficiency?
The symptoms and signs of HHL insufficiency usually correspond to the symptoms that typically appear with an undersupply of the hormones ADH and oxytocin. Oxytocin plays a big part in the birth process, inducing labor and rushing milk into the nipples.
The posterior pituitary (HHL), which is also more appropriately referred to as the neurohypophysis, is an integral part of the pituitary gland, but represents a development of the brain in evolutionary terms. In contrast to the anterior pituitary lobe (HVL), the HHL does not synthesize the secreted hormones itself, but serves the HHL as a store and activator of the hormones oxytocin and ADH produced in the hypothalamus.
Reduced hormone secretion or a complete failure of hormone secretion by the HHL is referred to as posterior pituitary insufficiency (HHL insufficiency). The concept of insufficiency simply expresses that the hormone release of oxytocin and the antidiuretic hormone ADH is disrupted or does not occur at all.
The mere fact that the hormone secretion of the HHL is disturbed does not say anything about the causes of the disturbed hormone release. For example, no conclusions can be drawn as to whether the causes lie in a functional disorder of the HHL or in the hypothalamus or in the transmission path of the “raw hormones” from the hypothalamus to the HHL. The transmission path consists of unmyelinated axons.
Causes
The posterior pituitary insufficiency occurring isolated from the anterior pituitary lobe (HVL) can have a variety of causes. One possible cause is inflammation of the HHL tissue itself, preventing it from responding adequately to control hormones in the hypothalamus to activate and release oxytocin and ADH.
Similar symptoms arise when the pituitary gland is affected by a tumor or when tumors or hemorrhages in the surrounding tissue impair the function of the HHL by occupying space. The reason for a malfunction or for a complete functional failure of the HHL can also lie in the transmission path of the non-activated hormones from the hypothalamus to the HHL.
For example, the non-myelinated axons are very sensitive to possible compression. They run within the pituitary stalk (infundibulum), which is an integral part of the HHL and provides the connection to the hypothalamus.
In very rare cases, a disturbance of the hypothalamus leads to reduced synthesis of the two hormones, which manifests itself symptomatically in HHL insufficiency. Of course, radiation therapy or traumatic brain injury (TBI) can also lead to insufficiency of the HHL.
Symptoms, Ailments & Signs
The symptoms and signs of HHL insufficiency usually correspond to the symptoms that typically appear with an undersupply of the hormones ADH and oxytocin. Oxytocin plays a big part in the birth process, inducing labor and rushing milk into the nipples.
In addition, oxytocin, which is sometimes also referred to as the cuddle hormone, has a positive systemic effect on the psyche in both men and women. It promotes the bond between two partners – comparable to the mother-child relationship, which is also controlled by oxytocin. The hormone facilitates and strengthens social connections and counteracts social phobias.
Oxytocin deficiency makes childbirth more difficult and women cannot breastfeed without oxytocin. The psychological effects of an oxytocin deficiency are diverse and vary from person to person. A lack of the antidiuretic hormone ADH, also known as vasopressin, prevents the necessary reabsorption of primary urine, resulting in severe water loss.
The disease is called diabetes insipidus, which can hardly be compensated for by drinking more – in extreme cases up to 20 liters per day. If the HHL insufficiency is caused by tumors or by hemorrhaging or other spatial demands, primary symptoms such as headaches and, in extreme cases, visual disturbances also occur in addition to the hormone deficiency symptoms.
Diagnosis & course of disease
In cases in which no primary symptoms and complaints are noticed, the suspicion of HHL insufficiency can only be triggered by the corresponding hormone deficiency symptoms. Imaging methods such as X -rays, computed tomography (CT), magnetic resonance imaging (MRI) or somatostatin receptor scintigraphy are used to confirm or reject the suspected diagnosis.
Since imaging methods do not always allow clear findings or can lead to misinterpretations, an endocrinological examination of the hormone levels in the serum is helpful in many cases to confirm the diagnosis. The course of the disease depends on the primary disease. If left untreated, HHL insufficiency can either persist or it can lead to a serious course, for example due to tumors of the pituitary gland.
Complications
Insufficiency of the posterior lobe of the pituitary gland usually causes various symptoms that can negatively affect both the psychological and physical condition of the patient. In most cases, the disease negatively affects the birth process. Even after the birth, the mother cannot breastfeed the child in most cases.
As a rule, the child then has to be fed artificially, although this leads to psychological problems for the mother. Likewise, social bonds are weakened and no longer properly respected, which can lead to problems with friends or with the partner. It is not uncommon for visual disturbances or headaches to occur as a result of the posterior pituitary gland insufficiency.
The patient’s quality of life decreases extremely as a result of the disease and it is not uncommon for the patient to suffer from various psychological upsets. The treatment of posterior pituitary insufficiency is carried out with the help of hormones, although there are no other complications. If the mother is unable to breastfeed the child, the child can be cared for in other ways. As a rule, there are no developmental delays in the child.
When should you go to the doctor?
Symptoms such as blurred vision, headaches in the back of the skull or a general feeling of illness indicate posterior pituitary insufficiency. A doctor’s visit is necessary if the symptoms mentioned persist for more than a week or rapidly increase in intensity over time. Affected persons should then immediately visit their family doctor and arrange for an examination. The symptoms may have a harmless cause that can be treated directly.
If a posterior pituitary insufficiency is actually the cause, the patient must be treated in a specialist clinic. Therefore, if there are clear signs such as the characteristic headaches and visual disturbances, medical advice should always be sought. Cancer patients are particularly susceptible to posterior pituitary insufficiency. There is also an increased risk of developing HHL for people who have suffered traumatic brain injury or who have undergone radiation therapy. Anyone who counts themselves among these risk groups must inform the responsible doctor in any case. In addition to the family doctor, a neurologist or an internist can also be consulted.
Treatment & Therapy
Treatment of HHL insufficiency can be aimed at curing the primary disease or treating the symptoms, which usually involves administration of replacement hormones. If primary diseases of the pituitary gland and especially the posterior pituitary gland can be treated causally, the undersupply of the hormones ADH and oxytocin can correct itself.
In all other cases in which it is no longer possible to restore the secreting effect of HHL, treatment consists of lifelong hormone replacement or hormone balancing therapy. Hormone therapy always involves direct administration of hormones.
This also applies in cases in which the pituitary gland normally regulates the hormone concentration by secreting control hormones, i.e. only causes a specific target organ to release the actual hormone more into the metabolism.
Prevention
There are no known direct preventive measures that could prevent the development of HHL insufficiency. The best protection is early detection of oxytocin and ADH deficiency. While a gradual onset of oxytocin deficiency is not immediately recognizable as such, if the ADH level in the blood serum is too low, it becomes noticeable through strong feelings of thirst, which should be clarified.
Aftercare
In the case of posterior pituitary insufficiency, direct aftercare measures are severely limited in most cases. As a rule, patients with this disease depend on a quick and early diagnosis so that further complications and worsening of the symptoms can be prevented.
In the case of posterior pituitary insufficiency, self-healing cannot occur. Therefore, the affected person should consult a doctor as soon as the first symptoms and signs of the disease appear in order to initiate early treatment. Those affected by this disease are usually dependent on taking various medications that can relieve the symptoms permanently.
It is always important to ensure that the correct intake and the correct dosage are taken. In the case of children, parents in particular should monitor and control the correct intake. Since the posterior pituitary insufficiency can also have a negative effect on other organs of the body, the person concerned should undergo regular examinations by a doctor in order to identify possible damage at an early stage. It cannot be universally predicted whether the disease will lead to a reduced life expectancy of the patient.
You can do that yourself
Patients with posterior pituitary insufficiency often need to take hormones throughout their lives. Until these hormones are perfectly adjusted, you should have a lot of patience, especially if the hormones were not prescribed in tablet form but in the form of nasal sprays or injections. After that, hormone replacement or hormone balancing therapy should be reliably integrated into the daily routine.
It should go without saying that hormone levels are checked regularly. To ensure adherence to the therapy required for this, it is advisable to keep a record of the blood tests and the hormone status determined. This is particularly helpful when patients go on vacation for a longer period of time or change their place of residence. In this way, new doctors can always get an accurate picture of the course of the disease.
Patients with posterior pituitary insufficiency may suffer from the fact that their bodies are no longer producing the oxytocin needed for proper social bonding. This can negatively affect the relationship with friends, family and partner and in the worst case even make it impossible. If the medication alone is not enough, a psychotherapeutic accompanying treatment is recommended.
Mothers with posterior pituitary insufficiency are often unable to breastfeed their child, which can be just as difficult psychologically. Here, too, psychotherapeutic treatment is recommended and in most cases is paid for by the statutory health insurance companies without any problems.
