By Dr. Marcus Judge

OSCE

In any OSCE examination, understand the pathology and reasoning behind each sign and symptom you elicit, even if the patient is 'normal'. This article explains how to perform an acromegaly examination and the key findings you should look for, showing you what each sign means and what conditions it may indicate.

Acromegaly is caused by excess growth hormone (GH) in adults, almost always due to a GH-secreting pituitary adenoma (a benign tumour of the pituitary gland, the hormone gland at the base of the brain). Because GH drives the liver to produce insulin-like growth factor 1 (IGF-1), the soft tissues, cartilage and bones continue to grow. In adults the epiphyseal growth plates (the areas at the ends of the long bones where growth takes place) have already fused, so height does not increase. Instead the extremities and face become coarser and larger. Excess growth hormone in childhood, before the growth plates fuse, causes gigantism. Many of the signs in this examination are the direct consequence of soft-tissue overgrowth. Others reflect the local effect of the pituitary tumour or the metabolic complications of the disease.

Contents

  1. Introduction
  2. General Inspection
  3. Hand Examination
  4. Arms and Blood Pressure
  5. Facial Examination
  6. Visual Fields and Eyes
  7. Neck Examination
  8. Cardiovascular and Respiratory Assessment
  9. Lower Limbs and Joints
  10. Completing the Examination
  11. Quiz

Introduction

Wash your hands and don personal protective equipment if appropriate.

Introduce yourself to the patient and ensure to mention your grade e.g. 3rd year medical student/junior doctor/consultant.

Confirm the patient's details using 3 points of identification, usually full name, date of birth and NHS or hospital number.

Briefly explain the examination and obtain consent, for example: "I would like to look at your hands and face, check your vision, and examine your pulse and blood pressure. Is that alright?"

Ask the patient if they are in any pain anywhere before you begin, as joint pain is common in acromegaly.

Position the patient seated on the edge of the bed or in a chair, and ensure their hands, forearms and face are exposed and accessible.

General Inspection

Begin by standing back and observing the patient from the end of the bed. In established disease the diagnosis of acromegaly is often suggested by the general inspection alone, but the features develop so slowly that in real life diagnosis is often delayed by years and must be confirmed with blood tests. Take time to build an overall impression before touching the patient.

Look for the characteristic coarsening of the facial features, large hands and feet, and an increase in overall body size. Patients often report that their rings no longer fit and that they have had to buy larger shoes or gloves, which is a useful clue to the gradual soft-tissue overgrowth.

Note the patient's height and habitus (overall body build). Acromegaly developing in adulthood does not increase height, but if excess growth hormone was present before the epiphyses fused (in childhood) the patient would have gigantism and be unusually tall.

If the patient is mobile, watch how they walk. An altered, unsteady gait may be seen, because the arthropathy (joint disease) of acromegaly and changes in the spine can both affect how the patient walks and increase the risk of falls.

Scan the bedside for clues such as a blood glucose monitor or insulin (suggesting associated diabetes mellitus), a visual field chart, or walking aids (reflecting the arthropathy that acromegaly causes). A deepened or husky voice may also be noticeable when the patient speaks, caused by thickening of the vocal cords and enlargement of the laryngeal (voice box) soft tissues and the sinuses (air-filled spaces in the facial bones).

Hand Examination

Inspect the hands first. In acromegaly the hands are typically large, broad and "spade-like", with thickened, doughy soft tissue and an increase in the size of the fingers. This is due to overgrowth of soft tissue, cartilage and bone driven by GH and IGF-1, rather than any swelling of the joints themselves. To gauge the degree of acral enlargement (enlargement of the hands and feet), hold your own hand against the patient's, palm to palm, and compare the overall span. The patient's hand often noticeably overlaps your own.

Assess the skin thickness by gently pinching the skin over the third metacarpophalangeal joint (the knuckle at the base of the middle finger) and comparing it with the equivalent skin on your own hand. Excessively thick skin supports the diagnosis and reflects the generalised soft-tissue expansion seen throughout the body. The skin may also feel oily and sweaty, as acromegaly increases the activity of sweat and sebaceous (oil-producing) glands, producing hyperhidrosis (excessive sweating).

Inspect the fingertips for capillary blood glucose testing marks. Excess growth hormone is a counter-regulatory (anti-insulin) hormone, so it promotes insulin resistance. Diabetes mellitus is a frequent complication, with a reported prevalence of 12% to 37%, and impaired glucose tolerance (blood glucose that is raised but still below the diabetes threshold) is also typical.

Acromegaly Hands SimpleMed

Image - An unaffected hand on the left compared with an enlarged acromegalic hand on the right, showing widened fingers and thickened soft tissue

Creative commons source by Philippe Chanson and Sylvie Salenave [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]

Carpal tunnel syndrome (compression of the median nerve at the wrist) is common in acromegaly, with a reported prevalence of 19% to 64%, and often appears before acromegaly is diagnosed. Most carpal tunnel syndrome in the general population has no known underlying cause. In acromegaly, soft-tissue overgrowth within the wrist compresses the median nerve as it passes through the carpal tunnel, the narrow passage at the front of the wrist. This causes pain, tingling and numbness in the thumb, index, middle and radial half of the ring finger. Look for wasting of the thenar eminence (the muscle bulk at the base of the thumb) as a sign of long-standing median nerve compression.

Two bedside tests can provoke the symptoms of carpal tunnel syndrome:

  • Tinel's test: tap firmly over the carpal tunnel on the palmar aspect of the wrist. A positive test reproduces tingling or paraesthesia in the median nerve distribution.
  • Phalen's test: ask the patient to hold their wrists in full flexion (back-to-back) for around 60 seconds. A positive test again reproduces the median nerve symptoms.

Finally, palpate the radial pulse, assessing the rate and rhythm. A normal rate is 60 to 100 beats per minute (bpm). This begins to assess the cardiovascular complications of acromegaly, which are an important cause of excess mortality in these patients.

Arms and Blood Pressure

Move up the arms and inspect the axillae (armpits) and skin. Acromegaly is associated with multiple skin tags (acrochordons), which are small benign outgrowths of skin that are particularly common in the axillae and neck. They are clinically relevant because their presence has been linked with an increased risk of colonic polyps, part of the recognised association between acromegaly and colorectal neoplasia (abnormal growths in the large bowel, including polyps and cancer).

While inspecting the axillae and neck, also look for acanthosis nigricans: velvety, thickened, darkened skin in the skin folds (flexures). This is a marker of the insulin resistance that growth hormone produces, and ties in with the impaired glucose handling seen in many patients.

You may also note proximal muscle weakness, as a chronic myopathy (muscle disease) can develop in long-standing disease. A quick bedside screen is to ask the patient to stand from a seated position with their arms folded across their chest. Difficulty doing so without pushing up on the arms of the chair suggests proximal weakness.

Offer to measure the blood pressure. Hypertension is common in acromegaly and arises from a combination of sodium and fluid retention (growth hormone has an anti-natriuretic effect on the kidney, which means that the kidney keeps hold of sodium instead of losing it in the urine) and increased vascular tone. Hypertension contributes substantially to the cardiovascular morbidity of the condition, so its identification is an important part of the examination.

Facial Examination

Inspect the face carefully, as it carries some of the most recognisable features of acromegaly. Look for coarse facial features overall, with thickened skin and accentuated facial creases.

Specific features to look for include:

  • Frontal bossing: prominence of the forehead and brow caused by overgrowth of the frontal bones and the underlying frontal sinuses.
  • Prognathism: protrusion of the lower jaw (mandible) due to bony overgrowth, often producing an underbite (malocclusion) where the lower teeth sit in front of the upper teeth.
  • Interdental separation: widening of the gaps between the teeth, as the jaw enlarges but the number of teeth stays the same.
  • Enlarged nose and lips: broadening of the nose and thickening of the lips from soft-tissue overgrowth.

Ask the patient to open their mouth and inspect the tongue for macroglossia (an enlarged tongue). This is significant beyond appearance. Enlargement of the tongue and the soft tissues of the upper airway predisposes patients to obstructive sleep apnoea (repeated blocking of the airway during sleep), a very common and important complication of acromegaly.

If you have not already done so, note any deepening of the voice, which results from thickening of the vocal cords and enlargement of the laryngeal cartilages and paranasal sinuses.

Acromegaly Facial Features SimpleMed

Image - The coarse facial features of acromegaly, including frontal bossing, an enlarged nose and prominent jaw, caused by bony and soft-tissue overgrowth

Creative commons source by Philippe Chanson and Sylvie Salenave [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]

Acromegaly Prognathism SimpleMed

Image - Prognathism in acromegaly, with protrusion of the lower jaw produced by overgrowth of the mandible

Creative commons source by Philippe Chanson and Sylvie Salenave [CC BY 2.0 (https://creativecommons.org/licenses/by/2.0)]

Visual Fields and Eyes

Assessment of the visual fields is one of the most important parts of the acromegaly examination, because it tests for the local effects of the pituitary tumour. The pituitary gland sits in the sella turcica (the bony hollow at the base of the skull), directly beneath the optic chiasm (where the two optic nerves cross). As a pituitary adenoma enlarges upwards out of the sella turcica (supra-sellar extension), it compresses the chiasm.

The fibres that cross within the optic chiasm are those carrying information from the nasal half of each retina, which correspond to the temporal (outer) half of each visual field. Compression from below therefore affects these crossing fibres first, producing the classic bitemporal hemianopia, which is loss of the outer halves of the visual field in both eyes. (Hemianopia means loss of half of the visual field.)

Test the visual fields using confrontation (comparing the patient's visual field with your own). Sit roughly one metre opposite the patient at the same eye level. Ask them to cover one eye while you cover your opposite eye. Bring a moving finger or red hatpin in from the periphery in each quadrant, and compare the patient's field with your own. Always test each eye separately. A defect that respects the vertical midline and affects the temporal fields of both eyes strongly suggests chiasmal compression.

Visual Field Defects SimpleMed

Image - Patterns of visual field loss. Compression of the optic chiasm from below by a pituitary adenoma classically produces a bitemporal hemianopia, with loss of the outer half of the field in both eyes

Image source by As eo [CC BY-SA 4.0]

Offer to complete the eye assessment. Test visual acuity. Examine the eye movements, because a large tumour may compress the cranial nerves in the cavernous sinus (a blood-filled space beside the pituitary gland). Perform fundoscopy (looking at the back of the eye with an ophthalmoscope) to look for optic atrophy from chronic compression.

A large pituitary adenoma can also disturb the surrounding gland. If the tumour compresses the pituitary stalk, the normal brake on prolactin release (prolactin is the hormone that stimulates milk production) is lost. Also, roughly a quarter of GH-secreting adenomas co-secrete prolactin, which means that they release prolactin as well as GH. The resulting hyperprolactinaemia (raised prolactin) may cause galactorrhoea (inappropriate milk production), menstrual disturbance or reduced libido, so offer to ask about these symptoms and, with a chaperone, to inspect for galactorrhoea.

Neck Examination

Examine the neck, paying particular attention to the thyroid gland. Acromegaly can cause a goitre (an enlarged thyroid gland), which may be diffuse or multinodular (containing several lumps), because growth hormone and IGF-1 stimulate the growth of thyroid tissue. Inspect the neck from the front. Ask the patient to swallow a sip of water, because a thyroid swelling will move upwards with swallowing. Then palpate the gland from behind to assess its size, symmetry and any nodules.

Although most patients remain euthyroid (have normal thyroid hormone levels), the increased prevalence of thyroid nodules is relevant because of the recognised association between acromegaly and thyroid neoplasia.

Large Goitre SimpleMed

Image - A visible goitre. Growth hormone and IGF-1 stimulate thyroid tissue, so a diffuse or nodular goitre may be found on examining the neck in acromegaly

Image source by Martin Finborud [Public domain]

Cardiovascular and Respiratory Assessment

Cardiovascular disease is still an important cause of death in acromegaly, although it is no longer the leading cause, so a focused cardiovascular assessment is essential. Chronic exposure to growth hormone and IGF-1 promotes growth of the heart muscle, leading to a specific acromegalic cardiomyopathy (disease of the heart muscle) with biventricular hypertrophy (thickening of the muscle of both lower heart chambers), diastolic dysfunction (the heart muscle does not relax and fill properly) and, in advanced disease, heart failure.

Auscultate the praecordium (the front of the chest over the heart) for any murmurs, as valvular thickening and regurgitation (backward leakage of blood across a valve) can occur. Listen for added heart sounds and, at the lung bases, for crackles that might indicate pulmonary oedema from heart failure. Check the ankles for peripheral oedema.

The combination of hypertension, cardiomyopathy, diabetes mellitus and obstructive sleep apnoea explains why cardiovascular risk is so markedly increased in these patients. Each component should therefore be actively sought during the examination.

Lower Limbs and Joints

Inspect the feet, which, like the hands, become large and broad due to soft-tissue and bony overgrowth; an increase in shoe size is a common historical clue.

Assess the joints for acromegalic arthropathy, a frequent and disabling complication affecting the knees, hips and spine. Excess GH and IGF-1 initially cause cartilage and periarticular (around the joint) tissue enlargement, which can produce pain and widened joint spaces. The altered joint shape and loading can later lead to degenerative change and osteophytes (bony spurs). This is distinct from ordinary osteoarthritis, and joint-space narrowing is not inevitable. Established damage may persist despite control of hormone excess. Look for joint swelling, reduced range of movement and walking aids.

Inspect the back as well, as degenerative change in the spine can produce a kyphosis (forward rounding of the upper back) and contribute to the altered gait noted on general inspection.

You may also note a proximal myopathy in the legs, contributing to weakness and difficulty rising from a chair.

Completing the Examination

Thank the patient and wash your hands.

Summarise your findings and offer a differential, clearly stating whether the clinical picture is consistent with acromegaly.

To complete the examination, suggest the following further assessments and investigations:

  • A full set of observations, including a formal lying and standing blood pressure to look for hypertension.
  • Capillary blood glucose as a quick bedside check, followed by a laboratory fasting plasma glucose and HbA1c (glycated haemoglobin, a measure of average blood glucose over about three months) to screen for diabetes mellitus.
  • A formal examination of the eyes and visual fields (ideally with formal perimetry, which maps the visual fields using a machine) and fundoscopy.
  • Comparison of the patient's appearance with old photographs, which helps demonstrate the slow change in features over time.
  • Biochemical confirmation: measure serum IGF-1 and interpret it against the age-adjusted reference range. In a patient with typical clinical features, IGF-1 above 1.3 times the upper limit of normal for age confirms acromegaly under the 2024 international Acromegaly Consensus Conference criteria. If results are borderline or unclear, repeat IGF-1 using the same validated assay (the same laboratory test); an oral glucose tolerance test (OGTT) assessing GH suppression may also help. An OGTT is not needed when the clinical and biochemical findings are clear.
  • MRI of the pituitary to identify and characterise the adenoma. Also assess the remaining pituitary hormone axes (the other pituitary hormones and the glands they control), including thyroid function and serum prolactin, to look for hypopituitarism (an underactive pituitary gland) or co-secretion (the adenoma releasing prolactin as well as GH).
  • Screening for complications, including an ECG and echocardiogram (an ultrasound scan of the heart), assessment for obstructive sleep apnoea, and colonoscopy (a camera examination of the large bowel) to look for polyps. This is commonly advised at diagnosis because acromegaly is associated with colonic polyps and colon cancer, although guidelines differ on whether every patient needs it.

Quiz

Preview the Acromegaly OSCE Examination quiz

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