Guillain-Barre syndrome is an immune mediated demyelination of the peripheral nervous system often triggered by an infection (classically Campylobacter jejuni). Characteristic features include progressive weakness of all four limbs, and it is classically ascending, affecting the lower extremities first. Sensory symptoms tend to be mild.

Functional neurological syndrome can be discounted due to presence of hard neurological signs. Multiple sclerosis can be excluded because of the presence of lower motor neuron signs and absence of upper motor neuron signs. Chronic inflammatory demyelinating polyneuropathy is the chronic form of Guillain-Barre syndrome.

The results of the blood exam are suggestive of aplastic anaemia which might be secondary to carbamazepine use. The use of antiepileptic’s, in particular carbamazepine and valproate, is associated with a nine fold increased risk of aplastic anaemia.

In type II hypersensitivity the antibodies, IgG and IgM bind to antigens to form complexes that activate the classical pathway of complement to eliminate cells presenting foreign antigens.

Vasopressin, also called antidiuretic hormone (ADH), regulates the tonicity of body fluids. It is released from the posterior pituitary in response to hypertonicity and promotes water reabsorption in the collecting ducts of the kidneys by the insertion of aquaporin-2 channels.. An incidental consequence of this renal reabsorption of water is concentrated urine and reduced urine volume. In high concentrations may also raise blood pressure by inducing moderate vasoconstriction.

This patient is having a myasthenic crisis. Opinions vary as to whether plasmapheresis or intravenous immunoglobulins should be given first-line. Plasmapheresis usually works much faster, but is more costly due to equipment.
Myasthenia gravis is an autoimmune disorder resulting in insufficient functioning acetylcholine receptors. Antibodies to acetylcholine receptors are seen in 85-90% of cases. Myasthenia gravis is more common in women (2:1).

Acute exacerbations of chronic obstructive pulmonary disease (COPD) are immediately treated with inhaled beta2 agonists and inhaled anticholinergics, followed by antibiotics (if indicated) and systemic corticosteroids. Methylxanthine therapy may be considered in patients who do not respond to other bronchodilators.
High flow oxygen would worsen his symptoms. Usually titrated oxygen (88 to 92 %) is given in such patients to avoid the risk of hyperoxic hypercarbia in which increasing oxygen saturation in a chronic carbon dioxide retainer can inadvertently lead to respiratory acidosis and death.

Ramipril is an ACE Inhibitor. Treatment with angiotensin-converting-enzyme inhibitors (ACEIs) or angiotensin receptor blockers (ARBs) has consistently been shown to reduce the risk of renal and cardiovascular morbidity and mortality in a range of patients. However, ACEI and ARB therapy increase serum potassium which increases the risk of hyperkalaemia.

Dysphagia or difficulty in swallowing. Endoscopy allows for visual examination of the oesophagus and is indicated in patients with dysphagia to determine the underlying aetiology, exclude malignant and premalignant conditions, assess the need for therapy, and perform therapy including dilation.

Bronchopneumonia presents as a patchy consolidation involving one or more lobes, usually the dependent lung zones, a pattern attributable to aspiration of oropharyngeal contents.

Symptoms of bronchopneumonia may be like other types of pneumonia. This condition often begins with flu-like symptoms that can become more severe over a few days. The symptoms include:
– fever
– a cough that brings up mucus
– shortness of breath
– chest pain
– rapid breathing
– sweating
– chills
– headaches
– muscle aches
– pleurisy, or chest pain that results from inflammation due to excessive coughing
– fatigue
– confusion or delirium, especially in older people

There are several factors that can increase your risk of developing bronchopneumonia. These include:
– Age: People who are 65 years of age or older, and children who are 2 years or younger, have a higher risk for developing bronchopneumonia and complications from the condition.
– Environmental: People who work in, or often visit, hospital or nursing home facilities have a higher risk for developing bronchopneumonia.
– Lifestyle: Smoking, poor nutrition, and a history of heavy alcohol use can increase your risk for bronchopneumonia.
– Medical conditions: Having certain medical conditions can increase your risk for developing this type of pneumonia. These include: chronic lung disease, such as asthma or chronic obstructive pulmonary disease (COPD), HIV/AIDS, having a weakened immune system due to chemotherapy or the use of immunosuppressive drugs.

Relative risk = (Incidence in exposed group)/incidence in unexposed group). So in this case RR = (50/100)/(50/200) = 2.