The Solitary Pulmonary Nodule

A solitary pulmonary nodule or coin lesion is an approximately round lesion that is less than 3 cm in diameter and that is completely surrounded by pulmonary parenchyma without other abnormalities.

Lesions larger than 3 cm are called masses and are often malignant.

Pulmonary nodules are usually discovered incidentally on CXR but CT scan is considered the required standard.

Radiographic features distinguishing benign and malignant:

Margins - two pattern of margin are relatively specific for cancer.

• Corona radiata/ spiculated appearance - very fine linear strands extending 4 - 5 mm outward from the nodule.

• Scalloped border - associated with intermediate probability of cancer.

Calcification - suggest it is a benign lesion.

• laminated or central pattern is typical of granuloma.

• popcorn pattern is seen in harmartomas.

Growth rate - the volume-dobuling time for malignant bronchogenic tumours is rarely less than a month or more than a year.

If the lesion is spherical, a 30 percent increase in diameter represents a doubling of volume.

Gynaecomastia

The pathophysiological process of gynaecomastia involves an imbalance between free estrogen and free androgen action in the breast tissue.

Evaluation

Once the diagnosis of gynaecomastia is established, it is important to review all medications, including over the counter drugs such as herbal products.

• Spironolactone
• Cimetidine
• Alcohol
• Marijuana
• Estrogen/anti-testosterone

Other causes that need to be considered and the investigations:

• hcG - increased in testicular tumour.

• Increased LH with decreased Testosterone - primary hypogonadism.

• Normal or decreased LH with decreased testosterone - prolactin secreting tumour or secondary hypogonadism ( check prolactin level )

• Increased LH and testosterone - Hyperthyroidism/androgen resistance ( check TFT )

• Normal or decreased LH and increased estridiol - Sertoli-Leydig's cell neoplasm or adrenal neoplasm

• Normal hcG, testosterone, estridiol and LH - idiopathic gynaecomastia

Adenomatous Polyps of the Colon

Colonic adenomas are the precursor lesions of almost all colorectal cancers but 90 % of adenoma do not progress to cancer.

Consensus guidelines for colonoscopic surveillance after polypectomy:

• 1 - 2 low risk adenomas - 5 to 10 years
• 3 - 10 low risk adenomas or any high risk adenoma - 3 years
• More than 10 adenomas - less than 3 years
• Inadequately removed adenomas - 2 to 6 months
• Small, rectal, hyperplastic polyps - 10 yr or other average risk screening option.

More intensive surveillance is indicated when the patient's family history is suggestive of hereditary nonpolyposis colorectal cancer, an adenomatous syndrome, or a hyperplastic polyposis syndrome.

High risk adenomas are adenoma larger than 1 cm or histologically advanced adenomas ( tubulovillous or villous and those with high grade dysplasia.

Approach to immunocompromised patients

Causes:

• Congenital

• Acquired

Age

Immunosuppressive medication

Malignancy

• Hodgkin's disease
• Chronic lymphocytic leukemia
• Multiple myeloma
• Solid tumors
  

Microbial infection

• HIV, AIDS
• Measles
  

Disorder of biochemical haemostasis

• Diabetes mellitus
• Renal insufficiency/dialysis
• Hepatic insufficiency/cirrhosis
• Malnutrition

Other

• Stress
• Asplenia/hyposplenism

General Recommendation for the care of the transplant recipient:

Immunization and prophylaxis

• Yearly influenza and pneumovax vaccine every 5 years
• PCP prophylaxis if necessary

Cancer Surveillance

• Male - Prostrate cancer screening
• Female - Mammogram, Pap smear yearly
• Both - Colonoscopy in patients over 50 years and annual dermatology screening

Cardiovascular

• Aggressive risk factors modification
• Aspirin unless contraindicated

Bone disease

• Calcium and vitamin D supplementation
• DEXA scan within 6 mths of transplantation and then yearly

Pregnancy and Heart disease

Cardiac disease is now the leading cause of maternal mortality in the United Kingdom.

Haemodynamic changes in pregnancy

• Plasma volume increases by 30 - 50 % during pregnancy.

• Systemic vascular resistance reduces by 30 %.

• Oxygen consumption increases throughout the pregnancy.

• Haemodynamic changes persist for 2 - 3 weeks post delivery but may not completely resolve for upto 12 weeks.

• During labour and delivery cardiac output is further increased, especially after delivery of placenta, due to increased venous return from uterine contraction.

Pre-pregnancy counselling and assessment

• It should be done by a cardiologist or obstetrician with an interest in heart disease in pregnancy.

• Counselling should include the effects of pregnancy on the mother and fetus as well.

Maternal Risks - It is important to be realistic with the prospective parents and if pregnancy is deemed high risk, alternatives such as adoption or surrogacy should be discussed and appropriate advice about contraception given.

• Predictors of adverse maternal events

NYHA class >II
Cyanosis ( SaO2 less than 90%
Prior Cardiovascular event
Systemic ventricular ejection fraction less than 40%
Left Heart Obstruction

Estimated risk of adverse event is 5 %, 27 % and 75 % with 0, 1 or > 1 of these risk factors respectively.

• There are some conditions that should be considered prohibitively high risk with a > 10 % risk of maternal death, and includes:

Pulmonary hypertension
Marfan syndrome with dilated aortic root ( risk reduced with surgical repair )
Severe left heart obstructive lesions ( risk reduced with repair ).
Systemic ventricular dysfunction

Fetal Risk

• In general, drugs known to be teratogenic should be stopped preconception or once pregnancy is confirmed.

ACEI
Angiotensin II receptor antagonists
Amiodarone
Warfarin
Spironolactone

MS, which is the most frequent VHD encountered during pregnancy, is often poorly tolerated when valve area is ,1.5 cm2, even in previously asymptomatic patients. Dyspnoea worsens between the third and fifth months, which corresponds to the increase in cardiac output. The persistence of dyspnoea or pulmonary hypertension is associated with a high risk of complications at delivery, thereby threatening the life of both the mother and foetus.

Severe AS is less frequently encountered during pregnancy. Complications occur mainly in patients who were symptomatic before pregnancy.225 The risk of heart failure during pregnancy or at delivery is low when mean aortic gradient is ,50 mmHg.

Foetal prognosis is also impaired in the case of stenotic heart valve disease, due to growth retardation, preterm delivery, and low birth weight. For these reasons, patients with severe MS or AS should be treated before pregnancy if possible, even in asymptomatic patients.

Chronic AR and MR are well tolerated during pregnancy, even when severe, provided LV systolic function is preserved.However, the risk of complications is high when LVEF is ,40%, the prognosis being close to that of cardiomyopathy. Conversely, acute regurgitation is poorly tolerated.

In patients with Marfan’s syndrome, the risk of aortic-related complications including dissection during pregnancy increases markedly when AR is more than mild or when maximum aortic diameter is .40 mm. In these cases, pregnancy should be preceded by replacement of the ascending aorta, in particular, when the native aortic valve can be preserved. Aortic complications should be considered in any patient presenting with chest pain or pain in the posterior thorax.

When the first visit occurs during pregnancy, early termination may be considered in the following situations:

• Severe LV dysfunction (EF ,40%).
• Marfan’s syndrome with aneurysm of ascending aorta 40 mm.
• Severe symptomatic stenotic valve disease, which cannot be treated using percutaneous procedures.

Immunosuppressant

Immunosuppressive agents are used to:

• Prevent the rejection of transplanted organs and tissues
• Treat autoimmune diseases or diseases that are most likely of autoimmune origin

Because the majority of them act non-selectively, the immune system is less able to resist infections and the spread of malignant cells.

Immunosuppressive drugs can be classified into five groups:

• Glucocorticoids
• Calcineurin inhibitors such as cyclosporin and tacrolimus
• Sirolimus derivatives such as everolimus, sirolimus
• Mycophenolate mofetil
  
• Antibodies
• Cytotoxics
  

Glucocorticoids:

• suppress cellular and humoral immune system
• anti-inflammatory effects

Calcineurin inhibitor - cyclosporin and tacrolimus

• Cyclosporin and tacrolimus block the action of calcineurin in activated T cells. This prevents production of interleukin-2 and other cytokines which normally stimulate T cell proliferation and differentiation.

• Common side effects include gingival hyperplasia, hirsutism and nephrotoxicity.

Sirolimus Derivatives:

• Bind to the same intracellular protein (FKBP-12 ), then blocks the activity of mammalian target of rapamycin (mTOR) kinase preventing cell cycle progression and cytokine-induced T and B cell proliferation.

• Common side effects include rash, neutropenia, proteinuria and interstitial lung disease.

Mycophenolate mofetil

• selectively suppresses lymphocyte proliferation and antibody formation by inhibiting inosine monophosphate dehydrogenase.

• Common side effects include GI symptoms.

Antibodies:

Antibodies are sometimes used as a quick and potent immunosuppressive therapy to prevent the acute rejection.

Includes:

• Polyclonal antibodies which inhibit T cell and cause lysis.
  
• Monoclonal antibodies which are directed towards exactly defined antigens.

Cytotoxics:

In immunotherapy, they are used in smaller doses than in the treatment of malignant diseases. They affect the proliferation of both T cells and B cells.

includes:
Alkylating agents - such as cyclophosphamide, which is probably the most potent immunosuppressive compound.
Anti-metabolites

• Folic acid analog - such as methotrexate
• Purine analogs - azathioprine and mercaptopurine

Azathioprine can cause irreversible bone marrow failure for those with a particular polymorphism of the TPMT gene.

Drug interactions with allopurinol.

Gastroparesis

Gastroparesis, also called delayed gastric emptying, is a disorder in which the stomach takes too long to empty its contents.

The vagus nerve controls the movement of food through the digestive tract. If the vagus nerve is damaged, the muscles of the stomach and intestines do not work normally, and the movement of food is slowed or stopped.

Major Causes of Gastroparesis

• diabetes
• surgery on the stomach or vagus nerve
• postviral syndromes
  
• anorexia nervosa
• medications, particularly anticholinergics and narcotics (drugs that slow contractions in the intestine)
  
• nervous system diseases, including abdominal migraine and Parkinson's disease
• smooth muscle disorders such as amyloidosis and scleroderma
• metabolic disorders, including hypothyroidism

Diagnosis

The diagnosis of gastroparesis is confirmed through one or more of the following tests.

• Gastric manometry
  
• Radioisotope gastric-emptying scan
• Upper GI endoscopy to exclude other causes of nausea
• USS to exclude the cholecystitis and pancreatitis.

Treatment

It is important to note that in most cases treatment does not cure gastroparesis—it is usually a chronic condition. Treatment helps the patients to manage the condition so that they can be as healthy and comfortable as possible.

Removal of causes of gastroparesis is important such as better glucose control.

Dietary approach

• six small meals a day instead of three large ones.
• Low fibre diet

Prokinetic Agents

• Metocloparamide
• Domperidone
• Ondansetron
• Erythromycin

Feeding tube or parenteral therapy

Newer therapy include gastric pacemaker

Work up for Transplant

Cardiovascular Investigation - vessels and heart ar the Achilles heel in the transplanted patient

Evaluation of iliac and lower extremity vessels prior to transplantation

• Approapirate procedure a stenotic lesions in these areas are doppler/duplex sonography or angiography. These examinations are particularly indicated in patients with signs of peripheral vascular occulsive disease.

Evaluation of cardiac performance

• Mainly two diseases must be excluded which are common in dialysis patients: 1) coronary artery stenosis ( present in 40 % of patients at the start of dialysis ), 2) Aortic valve calcification and stenosis.
• Stress echocardiogram are useful.
• If the stress echocardiogram reveals signs indicating previous MI, coronary angiogram is strongly recommended.
• Coronary angioplasty or bypass procedure are necessary, if required, before putting patient on the waiting list.
  

Evaluation of carotid arteries

• Carotid duplex/doppler is useful as coronary artery disease is an indicator of coronary artery disease.
• In polycystic kidney disease, cerebral aneurysm should be excluded by MRI.

Respiratory examination

• CXR
• Respiratory Function Test

Oncology

• Skin cancer - need dermatological review
  
• for women - need mammogram and pap smear
• for men over 50 yrs - need PSA and PRDE of prostrate gld
• for analgesic nephropathy patient - urothelial cancer need to be checked.
• There is a consensus that a waiting period of 5 yrs should be respected before the patient is put on the waiting list.
  

Exculsion of chronic bacterial or viral infection

Chronic Bacterial Infection:

• Tuberculosis
• Dental Check up for dental root abscess
• Cholecystolithiasis and diverticulosis need to be treated before transplantation

Chronic Viral Infection:

• Hepatitis B and C
• HIV
• CMV carrier status is important as well

Immunological Investigation

• HLA types
• Blood groups

Multiple Sclerosis

Multiple sclerosis is the chronic inflammatory demyelinating disease of the central nervous system.

Clinical course:

• Relapsing and remitting
• Primary progressive
• Secondary progressive

Management:

Symptomatic Treatment

• Anti-spasmodic agent
• Mild relapse - nil treatment.
• Moderate to severe relapse - high dose methylprednisolone.
• Recent accelerated deterioration of PP/SP MS - high dose methylprednisolone.

Disease modifying agent

• Interferon beta reduces the frequency of relapses in RR - MS by about a third and its severity.
• Glatiramer is useful in case of tolerance to Glatiramer.
• Natlizumab - if interferon beta and Glatiramer are ineffective.
• Mitoxantrone

Causes of Nephritis and Nephrotic syndrome

Nephritis Syndrome

Nephritic syndrome is characterized by proteinuria, hematuria, azotemia, red blood cell casts, oliguria and hypertension.

The main features are hypertension and RBC casts.

The proteinuria in nephritic syndrome is not severe, if it is severe the patient likely has a mix of nephritic syndrome and nephrotic syndrome.

Causes:

• IgA Nephropathy and Henoch Schonlein purpura
• Mesangiocapillary GN
• Idiopathic crescentic GN
• Lupus nephritis
• Post-infectious GN
• Anti-GBM disease
• ANCA positive small vessel vasculitis

Nephrotic Syndrome

It is a clinical syndrome defined as proteinuria of more than 3.5 g per day, hypoalbuminaemia, generalised oedema and hyperlipidaemia.

Causes:

• Minimal change nephropathy
• Membranous nephropathy
• Focal segmental glomerulosclerosis
• Mesangiocapillary glomerulonephritis
• Lupus Nephritis
• Diabetes glomerulosclerosis
• Renal amyloidosis

Acute Renal Failure

Differentiating acute and chronic renal failure

The only two consistently useful indicators are:

1) Previous measurement of renal function

2) USS - long standing renal disease leads to loss of renal parenchyma and reduce renal size. A small less than ( 9 - 10 cm ) echobright and often cystic kidneys are characteristic of chronic kidney disease.

Exception is Diabetic nephropathy which tend to have relatively normal size kidney!

3) Laboratory are rarely helpful:

• Normal Hb argue against CKD but anaemia can be found in both CKD and ARF.
• Low calcium and high phosphate are secondary to impaired synthesis of vitamin D as found in patient with CKD.

Classification of ARF

Acute renal failure can be divided into pre-renal, renal and post-renal.

Intrinsic renal ARF - encompass all causes of ARF in which renal parenchyma has been damaged.

Large Blood Vessels

• Renal artery stenosis
• Cholesterol emboli
• Renal Vein thrombosis

Small Blood Vessels and Glomeruli

• Glomerulonephritis
• Vasculitis
• Scleroderma renal crisis
• Thrombotic microangiopathies
• Malignant hypertension
  

Tubulointerstitium

• Acute Interstitial Nephritis
• Cast nephropathy ( complicating myeloma )
• Contrast nephrotoxicity
  
• Tumour lysis
• Urate nephropathy
  

Acute Tubular Necrosis

• Ischaemic
• Nephrotoxic - aminoglycosides, myoglobin

The Nephritic and myeloma screen are necessary if an intrinsic renal cause of ARF ( but not ATN ) is suspected.

• Infection - 2 sets of blood cultures & ASO titre, HIV and Hepatitis serology with cryoglobulin level.
  
• Myeloma screen - plasma protein electrophoresis and immunoglobulin levels
  
• Anti-nuclear antibody ( ANA )
• Rheumatoid factor ( RF )
• Anti-neutrophil cytoplasmic antibody ( ANCA )
• Anti-glomerular basement membrane antibody ( anti-GBM )

Hepatomegaly

Causes:

Fluid

• Infection/Inflammation

Acute/Chronic Viral Hepatitis
Autoimmune Hepatitis
Cholangiohepatitis
Liver abscess

• Right sided heart failure

• Budd Chiari Syndrome

Fibrous tissue - early cirrhosis

Cells

• Myeloproliferative disorder
• Leukaemia
• Lymphoma
• Thalassaemia
• HCC
• Metastatic tumor
  

Protein/Glycogen/Fat

• Fatty liver
• Amyloidosis
• Glycogen storage disease

Miscellaneous

• Cysts
• Reidel's lobe
• Low lying diaphragm - COPD

Diagnosis:

Sometimes the diagnosis of underlying aetiology for hepatomegaly is challenging.

Often history provides many clues to the diagnosis. Look for:

• Risk factors for viral hepatitis
• History of autoimmune hepatitis
• Foreign travels
• Thrombophilia for Budd Chiari syndrome
• History of alcohol intake
• Fever, night sweat and weight loss for haematological malignancy

Peripheral Neuropathy

There are several patterns of peripheral nerve disease:

• Mononeuropathy
• Multiple mononeuropathy
• Symmetrical polyneuropathy
• Plexopathy
• Radiculopathy
• Polyradiculopathy

The time course may be:

• Acute - reaching its nadir in <4 weeks
  
• Subacute - reaching its nadir in 4 - 8 weeks
• Chronic - taking 8 weeks to develop.

The deficit may be:

• Motor - proximal/distal & symmetrical/asymmetrical
• Sensory - the key features to look for here is pain and ataxia
• Autonomic

The underlying pathology may be:

• Axonal
• Demyelinating
• Mixed

Pure Motor:

Differential diagnosis includes - myopathy & disease of neuromuscular junction.

• Motor Neurone Disease
• Multifocal Motor Neuropathy

Prominent Motor symptoms together with sensory symptoms include:

• AIDP/CIDP
• Acute Intermittent Porphyria
• Lead Intoxication
• Charcot's Marie Tooth Disease

Pain:

Small Nerve Fibres involvement: has normal muscle power, reflexes and vibratory/proprioceptive senses as these are carried by large fibres. There will be reduced pinprick and thermal sensation in the affected area. Vibratory sensation can be mildly reduced at the toes.

The causes are extensive

• Mostly idiopathic
  
• Impaired glucose tolerance and Diabetes Mellitus and
  
• Sjogren's syndrome
• Hypothyroidism
• HIV infection/ Hepatitis C infection
• Vitamin B12 deficiency
  
• Neurotoxic Drug Exposure

Large Nerve Fibres involvement:

Sensory Ataxia: The best recognised causes are

• A paraneoplastic syndrome associated with anti-Hu antibodies, often due to small cell lung cancer
• Sjögren’s syndrome
  
• Cisplatin toxic neuropathy
  
• Pyridoxine toxicity
• many cases remain ‘idiopathic’ despite extensive workup and careful follow-up

Autonomic Features:

• Acute: AIDP
• Chronic: Diabetes and Amyloidosis

This blog emphasied about the symmetrical generalised neuropathy.

The differential diagnosis of more or less symmetrical generalised neuropathy is much more extensive and complicated than that of mononeuropathies.

Initial Investigations for symmetrical polyneuropathy include:

• Blood Test - FBC, eLFT, Ca, TFT, ESR, HbA1c, B12/Folate, serum protein electrophoresis
• Immunology - ANA
• Radiology - CXR
• Neurophysiology - Nerve conduction study
  

Chronic Axonal neuropathy:

Causes:

• Hereditary
• Infection - leprosy and HIV
• Diabetes
• Alcohol
• Amyloidosis
• Endocrinology - myxoedema and acromegaly
• Drugs
• Toxins
• Uraemia
• Cirrhosis
• Paraneoplastic

Chronic demyelinating neuropathy

Causes:

• Chronic inflammatory demyelinating polyradiculoneuropathy
• Multifocal motor neuropathy
• Para-protein associated demyelinating neuropathy
• Charcot-Marie-Tooth disease type 1 and type X.

Chronic Inflammatory demyelinating polyradiculoneuropathy - CIDP

It is important to distinguish CIDP from chronic axonal neuropathy because it responds well to treatement with immunotherapy.

Clues are:

• A relapsing course
• Proximal as well as distal weakness
• Increased CSF protein and normal cell count ( in at least 80 % )

Management:
Corticosteroids, intravenous immunoglobulin and plasma exchange are all beneficial but prolong treatment is necessary. In pure motor CIDP, which may be worsened by corticosteroids, IV Ig should be the first choice.

Multifocal motor neuropathy:

Clinically, it may resemble amyotrophic lateral sclerosis (ALS) with predominant lower motor neuron involvement, but muscle atrophy and more rapid progression are lacking.

Sometimes it can be confused with a pure motor form of CIDP as well.

The diagnosis depends on finding multifocal motor but not sensory conduction block at sites not subject to compression.

Management:
About 80 % of patients respond to IV Ig which has to be repeated every month.

Hereditary neuropathy:
The commonest cause is Charcot-Marie-Tooth disease. Other causes include:

• Hereditary sensory and autonomic neuropathy
• Distal hereditary motor neuropathy
• Familial amyloid polyneuropathy
• neuropathy associated with multisystem hereditary disorders such as metachromatic leukodystrophy, mitochondrial disorders and Refsum's disease.

Usually, the initial symptom of CMT is foot drop early in the course of the disease. This can also cause hammer toe, where the toes are always curled. Wasting of muscle tissue of the lower parts of the legs may give rise to "stork leg" or "inverted bottle" appearance. Weakness in the hands and forearms occurs in many people later in life as the disease progresses.

A definitive diagnosis for a specific type of CMT is established via genetic testing for most types.

Acute Neuropathy
Acute neuromuscular paralysis has a wide differential diagnosis but GBS is the commonest cause.

Differential diagnosis of acute neuromuscular paralysis include:
Cortical lesion- such as CVA, encephalitis
Cord lesion - compression from abscess, haematoma, tranverse myelitis
Peripheral neuropathy:

• Gullain - Barre syndrome
• Poliomyelitis
• Rabies
• Acute intermittent porphyria
• Drug induced
• Diphtheria
• Thiamine deficiency
• Critical illness neuropathy

Neuromuscular transmission:

• Tick bite paralysis
• Myasthenia gravis
• Lambert Eaton myasthenic syndrome

Disorder of muscle:

• Hypokalaemia
• Hypophosphataemia
• Inflammatory myopathy
• Periodic paralysis
• Acute rhabdomyolysis

Involuntary Treatment

Statutory Health Attorney

A statutory health attorney is someone with automatic authority to make health care decisions on your behalf if you are an adult whose ability to make decisions is permanently or temporarily impaired.

They can consent to most health care issues, including withdrawing life-sustaining measures.

You do not need to fill out forms or formally appoint a statutory health attorney. A person automatically acts in this role when the need arises because of their relationship to you. They do not need any special expertise to perform the role but must be over 18 and capable of making decisions about health care.

Those who can act as a statutory health attorney are (in order of preference, and provided they are readily available and culturally appropriate):

• the patient’s spouse or de facto partner (if the relationship is close and continuing)
• the patient’s primary carer, but not a paid carer (although you may receive a carer’s pension)
• a close adult friend or relative
• the Adult Guardian as a last resort.

Enduring Power of Attorney ( cannot be used in abortion, transplant and tissue donation.

Firstly, there are two types of power of attorney:

• general power of attorney
• enduring power of attorney.

A general power of attorney is given to someone to make financial decisions on your behalf when you are absent, for example, if you are overseas and need someone else to sell your house or pay your bills.

An enduring power of attorney is put in place in the event something happens to you (usually illness or accident) that makes you unable to make your own decisions.

Both types involve a formal agreement giving someone else the power to make decisions on your behalf. It works like this:

1. You sign a form giving power of attorney to the person of your choice.
2. You specify the types of decisions that the person you choose can make.
3. The person agrees to the appointment by signing the acceptance section of the form. This makes them your attorney.
4. As your attorney, they can then act on your behalf if necessary.

Adult Gardianship

The role of the Adult Guardian is to protect the rights and interests of adults who are unable to make decisions for themselves. This lack of decision-making ability, known as impaired capacity, may be caused by intellectual or psychiatric disability, acquired brain injury, dementia or temporary illness such as delirium.

As an independent statutory officer, the Adult Guardian operates free from inteference from government and non-government organisations.

Both the Adult Guardian and Public Advocate are concerned with protecting these people’s rights and interests. However, the Public Advocate does not deal with individual cases, but looks at widespread deficiencies in institutions and systems that affect a large number of people.

For example, while the Adult Guardian might obtain a warrant to remove a person with impaired capacity who is being exploited by a carer, the Public Advocate looks at how the system has failed this person, and could be failing others in similar situations.

Advance Health directive

If you become seriously ill, unconscious or are unable to communicate your health care wishes, critical decisions may need to be made. You can make an advance health directive to make your wishes known in case you are in this situation.

You can make a directive if you are over 18 and have the capacity to do so. This means that you:

• understand the nature and consequences of your health care decisions
• understand the nature and effect of the directive
• freely and voluntarily make these decisions
• communicate decisions in some way.

Motor Neurone Disease

Epidemiology
The incidence is approximately 2 in 100 000 population per year and the average age of onset is roughly 65 years.

Types:
Amyotrophic lateral sclerosis ( ALS )

• Fundamental to the diagnosis is progressive weakness with mixed upper and lower motor neuron signs. Brisk reflexes in the presence of local wasting is a strong clue to the diagnosis.
• Visible fasciculations are usually prominent but tend to fade as the illness progresses.
• Differential diagnosis includes cervical spondylotic myeloradiculopathy and paraneoplastic neuromuscular syndrome.

Progressive muscular atrophy:

• True lower motor neuron MND is rare because many patients develop upper motor neuron signs at some point in the disease and are probably best classified as lower motor neuron predominant ALS.
• Differential diagnosis includes conduction block neuropathy, paraneoplastic neuropathy, X linked spinobulbar muscular atrophy ( Kennedy's syndrome ) and adult onset spinal muscular atrophy.

Primary lateral sclerosis:

• rare and accounts for 1 - 2% of MND.
• It is characterised by an ascending spastic tetraparesis with involvement of speech in the majority by 3 years.
• Urinary urgency is common.

Flail arm variant:

• Bilateral weakness and wasting of the proximal upper limb which may not spread to other regions for a number of years is sometimes associated with a dropped head.
• Despite proximity of the affected segments to the respiratory neurons, vital capacity may be unaffected until late in the disease.

Lower limb onset:

• It may remain confine to lower limb and present with with gradual ascending distal weakness.

Progressive bulbar palsy:

• The speech and swallowing involvement is the early features of a condition which rapidly generalises to the limbs and respiratory msucles and has a poor prognosis.

Investigations:
Essential

• Blood test - FBC, eLFT, Ca/PO4, ESR, CK and plasma protein electrophoresis.
• Nerve conduction study and EMG
• MRI spine / brain as indicated by clinical signs

In selective cases

• Blood test - B12, antineuronal antibodies, HIV serology, lyme serology and antiacetylcholine receptor antibodies
• Lumbar puncture
• Muscle biopsy

Treatment:
Aim for supportive treatement.
Riluzole is currently the only drug licensed for the treatment of MND.

• The probability of survival at 1 year after starting the drug is 9 % greater than the placebo ( 2 -3 months greater life expetancy ).
• There is no evidence of any effect on quality of life or improvement in specific symptoms.

Wrist Drop

Wrist drop is due to weakness of extensor carpi radialis longus ( supplied by C5/6 and the radial nerve ) and the extensor carpi ulnaris ( supplied by C7/8 and the posterior interosseous branch of the radial nerve ).

Anatomy of radial nerve:
It originates from the posterior cord of the brachial plexus with roots from C5, C6, C7, C8 & T1.

Branches

• Above spiral groove - nerve to triceps
• Below the spiral groove and above the elbow - brachioradialis
• Below the elbow - nerve to extensor carpi radialis longus and posterior interosseus nerve

Posterior interosseus nerve supply the extensor carpi ulnaris and extensor digitorum.

Radial nerve has sensory supply to posterior arm, forearm and dorsum of hand.

Causes of wrist drop:

• Radial nerve lesion
• Radiculopathy ( C7,8 ), if there is involvement of the finger flexors as well.
• Cortical lesion

Management:

• Nerve Conduction Study should be done.
• Spontaneous recovery is the rule and splinting helps hand function.
• If the palsy last more than 12 weeks then surgical decompression is an another option.

Pulmonary Hypertension

Pulmonary Hypertension is a mean pulmonary artery pressure more than 25 mmHg, with a pulmonary capillary or left atrial pressure less than 15 mmHg.

Causes:

Pulmonary arterial hypertension

• Sporadic
• Familial
• Related to:
• Collagen vascular disease
• HIV infection
• Drugs and toxins - fenfluramine
• Systemic to pulmonary shunts - ASD, PDA, Portal Hypertension

Pulmonary Venous Hypertension

• Left sided heart disease such as MS, LVF, AS

Pulmonary Hypertension associated with hypoxaemia

• Sleep disordered breathing
• Long term exposure to high altitude
• COPD
• Interstitial lung disease

Pulmonary Hypertension due to chronic thrombotic disease

• Pulmonary embolism

Miscellaneous

• Sarcoidosis
• Compression of pulmonary vessels such as tumour

Treatment:
General:

• Anticoagulation - all patients with pulmonary hypertension are at risk of venous thromboembolism and intrapulmonary thrombus because of sluggish pulmonary blood blow, dilated heart chambers and venous stasis.
• Long term oxygen therapy
• Immunization with annual influenza and pneumococcal vaccine.

Vasodilator therapy

• Calcium channel blocker - nifedipine and amlodipine
• Prostaglandin analogues - ilioprost
• Endothelin receptor antagonists - bosenten
• Phosphodiesterase inhibitors - sildenafil