Patients may need hormone replacement therapy for a number of reasons. Pituitary tumours are the most common cause of hypopituitarism. The tumour may have compressed or damaged the pituitary tissue and patients found to have hypopituitarism should be referred to a specialist Endocrinologist.
Surgery to remove the tumour may cause temporary or permanent damage and Radiotherapy may (over a period of several years) also irreversibly affect pituitary function. After treatment, long-term monitoring of pituitary function is required, which should be carried out by a specialist endocrinologist. The time interval between endocrine assessments will vary with the patient and the treatment received, but will probably be at intervals of 6-12 months immediately post-treatment, increasing to annual or biennial in the longer term.
The correct route of referral is through an endocrinologist rather than neurosurgeon or others. Please see ‘Who and When to Refer’ (factsheet 15).
GH replacement is required in children with low GH levels and slow growth rate. GH also has important effects in adult tissues such as bone, fat and muscle, and lack of GH may increase mortality rates from heart disease. Until recently the lack of widely available supplies of GH has restricted this therapy to children. However human recombinant Growth hormone is now available, which is free from risk of Creutzfeldt-Jacob disease (CJD), and has been shown to be clinically effective. Adults who suffer from biochemically documented GH deficiency, and who exhibit excessive tiredness, muscle weakness, weight gain, anxiety and depression, may benefit from GH therapy. GH is administered by daily Subcutaneous injection. The dose for
adults is considerably lower than that required for children (women require more GH than men). The reported side effect of GH therapy is fluid retention but this is rarely a problem with carefully titrated therapy in current practice. The evidence suggests that GH therapy is clinically effective; it may also improve bone mineral density in adults with GH deficiency. Replacement therapy with GH has now been approved by NICE in patients selected on the
basis of a quality of life deficit.
FSH & LH
FSH and LH secreted by the Pituitary gland stimulate the production of Oestrogen, Progesterone and Testosterone. If FSH and LH are no longer produced, because of pituitary damage, sex hormone replacement with oestrogen and progesterone or testosterone is usual, unless fertility is required. In the longer term sex hormone replacement reduces the risk ofosteoporosis and cardiovascular disease in both men and women. Testosterone can be given as a gel, intramuscularly, by implant, buccal SR and patches. Oestrogen/progesterone can be given as skin patches or as pills.
For fertility, treatment with Gonadotrophins is required at a specialist centre which provides effective monitoring. The human recombinant gonadotrophins now available are free from possible risk of new variant CJD. The objective is a singleton pregnancy and a multiple pregnancy should be considered as a failure of treatment. The specialist centre should have high-resolution ultrasonography available.
HRT is safe for women of pre-menopausal age, in whom the benefits of maintaining bone strength outweigh the deficits, and breast cancer has not been shown to be a problem.
ACTH deficiency is treated by prescribing Hydrocortisone or alternatively prednisolone (not recommended for children). The average dose requirement of hydrocortisone is 20 mg and most patients feel better if they have 3 doses - on waking, midday and early evening (5-6pm). In normal health, the lowest levels of Cortisol are between 6pm and 6am. Patients will need to learn the situations in which a higher dose of steroid should be taken. Examples are:
Supplies of tablets and a steroid card should always be carried and wearing a Medic Alert or similar bracelet is important in case of accident. Learning the skill of self-injection of hydrocortisone (or encouraging another member of the family to do so) can be potentially life saving, particularly if patients wish to travel to areas where medical care is not readily available. Full instruction on Intramuscular injection technique should be provided by hospital clinic or general practice. Urgent injection of hydrocortisone is indicated in emergency situations especially when intake of tablets is compromised e.g., by vomiting.
In the absence of the normal production of TSH by the pituitary gland patients require L-Thyroxine. Thyroxine has a relatively long half life (several days), so that if a tablet is forgotten no action is required.
Diabetes Insipidus may be a transient effect of surgery or a long-term result of damage to the Hypothalamus or posterior pituitary. AVP (ADH) is replaced by giving Desmopressin (referred to as DDAVP) provided as tablets or a nasal spray. Patients should be warned not to drink too much and a sensible precaution may be to leave out one treatment each week to prevent water overload. DI may disappear spontaneously. The only way to check this is to stop the treatment.
No replacement formulation is available or necessary under normal circumstances. The absence of prolactin may lead to an inability to breast-feed.
QUESTIONS PATIENTS MAY ASK
Will I have to take tablets in the long term?
If, as often happens, the Pituitary tumour or its treatment have caused hypopituitarism, this does not usually recover and the patient will need long term replacement therapy.
Will I need regular check-ups?
Yes, but as pituitary tumours are usually well controlled and grow very slowly, if at all, outpatient appointments are usually made 12 months to 2 years apart.
Will I need regular scans?
Perhaps, but again, these too are carried out years apart.
Have I inherited this, will my children get it?
There is ongoing research into familial incidence e.g. in Gigantism, but the majority of cases are sporadic.
RESOURCES FOR PATIENTS
available from The Pituitary Foundation HelpLine or our website www.pituitary.org.uk or our Endocrine Nurse HelpLine
Patient Information Booklet: Hypopituitarism and Replacement Therapy
Other information and resource links available at www.pituitary.org.uk
MORE SPECIALIST RESOURCES
Management of Pituitary Tumors: The Clinician’s Practical Guide (2003) (Second Edition), Editors and authors Michael P. Powell, Stafford L. Lightman and Edward R. Laws. Humana Press, Totowa, New Jersey
Pituitary Tumours. Recommendations for service provision and guidelines for management of patients. Consensus statement of a working party (1997) RN Clayton & JAH Wass (Eds)
London: Royal College of Physicians
The Diagnosis and Treatment of Pituitary Insufficiency (1997) Lamberts SWJ (Ed) Bristol, UK: BioScientifica
Endocrinology (1997) Levy A & Lightman SL New York: Oxford University Press
Treating Acromegaly. (1994) Wass JAH (Ed) Bristol, UK: Society for Endocrinology
The Epidemiology, Pathogenesis and Management of Pituitary Tumours (1998) Webb SM (Ed) Bristol, UK: BioScientifica
©2011 Version 3 (To be reviewed by 2013)