Acromegaly

Acromegaly    YQ54C8JKYS4B
Acromegaly, pituitary, hypophysis
Acromegaly is a disorder that occurs due to an excess secretion of growth hormone (GH)

Epidemiology:
  • Prevalence is approximately 40-60 million
  • Affects M: F with a ratio of 1: 1
  • Mainly affects people between the ages of 30-50 years
Pathophysiology:
  • GH (or somatotropin) is secreted by the anterior pituitary gland
  • GH stimulates soft tissue and skeletal growth indirectly through the secretion of insulin like growth factor-1 (IGF-1) from the liver.
  • The production of GH is regulated by GH-releasing hormone and GH-inhibiting hormone (somatostatin), both released from the hypothalamus
  • Acromegaly occurs due to hyper secretion of GH
  • 99% of time this occurs from a pituitary tumour 
  • Pituitary tumours are almost always benign, and divided into macroadenoma (>1cm) and microadenoma (<1cm)
  • Rarely ectopic secretion of GH-releasing hormone occurs from carcinoid tumours
Clinical features:
  • If excess GH secretion occurs before epiphyses have fused, then gigantism results
  • Most commonly though GH releasing pituitary tumours occur in adults, leading to acromegaly
  • Clinical features occur due to excess hormone secretion, local pressure, and hypopituitarism.
Symptoms:
  • Sweating
  • Headache (due to local pressure)
  • Increase size of hands and feet (increase ring and shoe size)
  • Oligo/amenorrhoea
  • Infertility
  • Proximal muscle weakness
Signs:
  • Coarsening of facial features
  • Prominent supra-orbital ridges
  • Prognathism (prominent lower jaw)
  • Increased interdental spacing
  • Macroglossia (enlarged tongue)
  • Doughy spade like hands
  • Carpel tunnel syndrome
  • Hoarse voice
Investigations:
Random GH measurements – GH is secreted in a pulsatile manner, with secretion increasing in stress, sleep and puberty, and reducing in pregnancy. Therefore random GH measurements are not very useful for diagnosis
 Serum IGF-1 – This can be used as a screening test, In most cases serum IGF-1 levels correlate with GH secretion over the past 24 hrs
    OGTT  - This is the diagnostic test for acromegaly. Normally rising levels of glucose inhibit GH secretion, thus in the OGTT, GH levels should be undetectable (< 2mU/L) once glucose is administered. However, in acromegaly there is a failure to suppress GH secretion.
    MRI of pituitary fossa
    Investigate any potential complications
        Full pituitary hormone profile  (hypopituitarism)
        Visual fields and acuity   (bitemporal hemianopia can occur due to compression of optic chiasm by pituitary tumour)
        Fasting glucose   (IGT)
        ECG, echo (Heart failure)

Management:
1. Surgical:
  • Trans-sphenoidal surgery
  • First line treatment
  • High cure rates for microadenoma
  • Post op  (3 months) investigations needed.
  • Measure GH day curve or repeat OGTT
  • Pituitary function tests to check for hypopituitarism
  • If GH remains high, further second line medical or radiotherapy needed
2. Medical:
  1. Somatostatin analoges: e.g. lanreotide, octreotide (IM injections) 
  2. Side effects:
  • Pain at injection site
  • GI- N&V, abdominal pain, flatulence, diarrhoea, gallstones
  • Impaired glucose tolerance
  • Highly selective GH receptor antagonist (pegvisomant [ s.c injections] ) is available for patients with inadequate response to surgery, radiation or both and to treatment with somatostatin analogues
3. Radiotherapy:
  • If surgery is inappropriate
  • Adjuvant to surgery
Follow up
Yearly
GH and IGF-1 measurement +/- OGTT
Visual fields
Clinical photos
Cardiovascular assessment. Aim for GH < 5mU/L to reverse mortality risk


Complications

    Diabetes Mellitus (10%), Impaired glucose tolerance (25%) [GH is counter regulatory to insulin]
    Vascular
        HTN
        Cardiomyopathy
        Heart failure
        Increased risk of IHD and stroke
    Osteoporosis
    Obstructive sleep apnoea [due to soft tissue swelling in larynx]
    Malignancy- It is still controversial whether acromegaly increases risk of developing colonic polyps and colonic carcinoma
    Hypopituitarism +/- local mass effect


Prognosis

    High mortality if untreated
    Mortality increased by 2-3 fold mainly due to cardiovascular risk



Examining for Acromegaly
Very common station in OSCEs although the condition itself is rare. Usually in OSCE the patient will have been treated, and thus the disease is not active, but many of the physical feature may remain.

Hands

    Size of the hands – compare to your own. Often grossly enlarged
    Skin fold thickness – again, compare to your own. Often increased in acromegaly
    Palm – feel for boggyness of the palm
    Sweating – feel the palms for sweating
    Thenar eminence / median sensory distribution – check for thenar eminence wasting and sensation on the lateral 3 ½ fingers (carpal tunnel syndrome)
    Proximal myopathy – check the power in the upper arm



Face

    Prominent supra-orbital ridges
    Large tongue
    Large ears
    Prognathism – an ‘underbite’ – the lower teeth protrude out below the upper ones



Visual Fields

    Check the visual fields


Cardiovascular system

    Check the BP (may be raised)
    Check for cardiomegaly

o   Displaced apexed beat
o   Raised JVP

Epistaxis

nosebleed, nose bleed, epistaxisMost nosebleeds arise from little’s area on the nasal septum. Five arteries anastomose to form little’s area:
1) Anterior Ethmoid Artery
2) Posterior Ethmoid Artery
3) Sphenopalatine Artery
4) Great Palatine Artery
5) Superior Labial Artery


Causes
Local:
  • Idiopathic
  • Trauma – nose picking, nasal fracture
  • Drug Induced – Nasal sprays, anticoagulants
  • Foreign Body
  • Rhinitis
Systemic:
  • Clotting disorders
  • Hypertension
  • Vasculitis (e.g Wegener’s Granulomatosis)
  • Hereditary Haemorrhagic Telangiectasia (a.k.a Osler-Weber-Rendu disease, an autosomal dominant condition causing oral telangiectasia and epistaxis)
Management
  • Airway, Breathing, Circulation!
  • Gain IV access with a large bore cannula
  • Send bloods for FBC, Group & Save and a clotting screen
  • Give IV fluids
  • Get the patient to sit upright, lean forwards and pinch the soft part of the nose
  • Advise the patient to spit out any blood in the mouth
  • Monitor pulse and blood pressure for signs of hypovolaemic shock
  • If a bleeding vessel is visible consider cautery with silver nitrate
  • Failing this pack the nose with Merocel nasal packs
  • If examination suggests a posterior haemorrhage (i.e from the sphenopalatine artery) then try a balloon catheter to compress the bleeding vessel
  • If this fails to stop the bleeding then the patient may need surgical ligation of the sphenopalatine artery

Written by Rachel Smith

    Dupuytren's Contracture

    Dupuytren's Contracture

    Dupuytren's Contracture is a progressive flexion deformity of the fingers, typically affecting the 4th (ring) finger. Also commonly affects the little finger, and rarely the middle finger. It is a result of contracture and fibrosis of the palmar aponeurosis.
    It is usually painless, and can affect one or both hands.

    Dupuytren's Contracture
    Epidemiology
    -          More common in men (10:1)
    -          Increases after age 45
    -          Tends only to affect those of Scandinavian and Northern European origin, as well as those from the Iberian peninsula and Japan.

    Etiology
    -          It is believed that in about 70% of cases it is the result of a genetic disorder whereby susceptible individuals who are subsequently exposed to further risk factors.  These factors can include:
    o   Liver disease
    o   Diabetes
    o   Epilepsy
    -          It can also be ideopathic

    Presentation
    -          Often a tender nodule on the palm is the first sign
    -          Deformity is progressive and follows later
    -          Pain subsides as it progresses
    -          Eventually the whole hand becomes arched, and there is contracture of the MCP and interphalangeal joints

    Management
    -          Steroid Injections are useful in early presentations of a tender nodule, and can prevent the formation of the contracture
    -          Surgery is indicated if:
    o   The hand can’t be placed flat on a flat surface
    o   There is contracture of the PIP joints
    -          Surgery involves careful removal of the affected palmar aponeurosis around neurovascular bundles (which are left behind). Recurrence can occur particularly if the dissection for removal is not adequate, and/or commonly if the patient is young at the time of surgery
    -          Injected collagenase – is a new treatment that has been shown to reverse contracture in some patients but is not widely used.
    Dupuytrens Contracture Dupuytren's Contracture Post Surgery
    Dupuytren's Contracture Dupuytren's Contracure after surgery

    Notes by Tom Leach

    Bacterial Vaginosis (BV)

    Bacterial Vaginosis (BV) std


    THE most common cause of pathological vaginal discharge. It can be caused by an overgrowth of many types of bacteria, usually anaerobes. There is also often a decrease in the number of lactobacilli. It is not sexually transmitted.



    Epidemiology

    - Affects 10% of women in the UK, but most cases are asymptomatic

    Presentation

    - A smelly (fishy) discharge, usually white / gray in colour. This idscharge is made up of waste products produced by the colonising anaerobes.
    - Vaginal itch (not in all cases)
    - Not usually inflamed

    Investigations

    - Whiff test (yes, really!) – potassium hydroxide (KOH) is added to a sample of the vaginal discharge. If a strong fishy odour is produced – the test is positive for bacterial vaginosis
    - pH - >4.5
    - Triple swabs (chlamydia, gonorrhoea, and a ‘general’ swab for culture)
    o Microscopy – reduced levels of lactobacilli, and increased levels of other bacterial agents, leukocytes absent, presence of clue cells
    o Culture – to define the predominant causatory agent

    Differentials

    Trichomoniasis is the only other likely cause of an offensive discharge, but this is usually yellow, and on microsocpy shows the prescence of protozoa with flagella
    Risks
    - Increased risk of pre-term labour
    - Intra-amniotic infection
    - Increased susceptibility to HIV
    - Post-termination sepsis

    Treatment

    - Metronidazole PO – one-off dose – 2g
    - Clindamycin – 2% cream – apply once at night to the vagina for 7 days
    o If recurrent problems, then treating the partner may resolve the situation

    Written by: Tom Leach