This is a picture of bone marrow failure secondary to acute myeloid leukaemia (AML). AML is the acute expansion of the myeloid stem line, which may occur as a primary disease or follow the secondary transformation of a myeloproliferative disorder. It is more common over the age of 45 and is characterized by signs and symptoms largely related to bone marrow failure such as anaemia (pallor, lethargy), frequent infections due to neutropenia (although the total leucocyte count may be very high), thrombocytopaenia (bleeding), ostealgia, and splenomegaly.

The disease has poor prognosis if:
1. Age of the patient >60 years
2. >20% blasts seen after the first course of chemotherapy
3. Chromosomal aberration with deletion of part of chromosome 5 or 7.

Acute promyelocytic leukaemia (APL) is an aggressive form of AML.

Other listed options are ruled out because:
1. Von Willebrand disease: may present with epistaxis and bleeding gums in severe cases but rarely with abnormalities on blood results.

2. Acute lymphoblastic leukaemia: mostly seen in children.

3. Lymphoma: usually presents with rubbery enlargement of lymph nodes.

4. Warfarin overdose: no bilobed large mononuclear cells seen on blood film.

The most probable diagnosis of this patient is Cotard syndrome with major depressive disorder.

Cotard syndrome is a rare mental disorder where the affected patient believes that they (or in some cases just a part of their body) is either dead or non-existent. This delusion is often difficult to treat and can result in significant problems due to patients stopping eating or drinking as they deem it not necessary. Cotard syndrome is often associated with severe depression and psychotic disorders (like schizophrenia).

Other delusional syndromes:
– Othello syndrome is a delusional belief that a patients partner is committing infidelity despite no evidence of this. It can often result in violence and controlling behaviour.
– De Clerambault syndrome (otherwise known as erotomania), is where a patient believes that a person of higher social or professional standing is in love with them. Often this presents with people who believe celebrities are in love with them.
– Capgras syndrome is characterised by a person believing their friend or relative had been replaced by an exact double.
– Couvade syndrome is also known as ‘sympathetic pregnancy’. It affects fathers, particularly during the first and third trimesters of pregnancy, who suffer the somatic features of pregnancy.
– Ekbom syndrome is also known as delusional parasitosis and is the belief that they are infected with parasites or have ‘bugs’ under their skin. This can vary from the classic psychosis symptoms in narcotic use where the user can ‘see’ bugs crawling under their skin or can be a patient who believes that they are infested with snakes.

A single dose of intravenous magnesium sulphate is safe and may improve lung function and reduce intubation rates in patients with acute severe asthma. Intravenous magnesium sulphate may also reduce hospital admissions in adults with acute asthma who have had little or no response to standard treatment.

Consider giving a single dose of intravenous magnesium sulphate to patients with acute severe asthma (PEF <50% best or predicted) who have not had a good initial response to inhaled bronchodilator therapy. Magnesium sulphate (1.2–2 g IV infusion over 20 minutes) should only be used following consultation with senior medical staff.

Tumour marker CA 15-3 is mostly associated with breast cancer.

Tumour markers can be divided into:
1. Monoclonal antibodies
CA 125: Ovarian cancer, primary peritoneal cancer
CA 19-9: Pancreatic cancer
CA 15-3: Breast cancer

2. Tumour specific antigens
Prostate specific antigen (PSA): Prostatic carcinoma
Alpha-feto protein (AFP): Hepatocellular carcinoma, teratoma
Carcinoembryonic antigen (CEA): Colorectal cancer
S-100: Melanoma, schwannomas
Bombesin: Small cell lung carcinoma, gastric cancer

3. Enzymes
Alkaline phosphatase (ALP)
Neuron specific enolase (NSE)

4. Hormones
Calcitonin
Antidiuretic hormone (ADH)
Human chorionic gonadotropin (hCG)

Gastrin is released by G cells in the antrum of the stomach. It stimulates secretion of gastric acid (HCl) by the parietal cells of the stomach and also aids in gastric motility. It is released in response to the following stimuli: vagal stimulation, antrum distention, hypercalcemia. It is inhibited by the following: presence of acid in stomach, SST, secretion, GIP, VIP, glucagon, calcitonin.

If a pleural effusion is present, a diagnostic thoracentesis may be performed and analysed for pH, lactate dehydrogenase, glucose levels, specific gravity, and cell count with differential. Pleural fluid may also be sent for Gram stain, culture, and sensitivity. Acid-fast bacillus testing may also be considered and the fluid may be sent for cytology if cancer is suspected.

The following findings are suggestive of an empyema or parapneumonic effusion that will likely need a chest tube or pigtail catheter for complete resolution:
-Grossly purulent pleural fluid
-pH level less than 7.2
-WBC count greater than 50,000 cells/µL (or polymorphonuclear leukocyte count of 1,000 IU/dL)
-Glucose level less than 60 mg/dL
-Lactate dehydrogenase level greater than 1,000 IU/mL
-Positive pleural fluid culture

The most often used golden criteria for empyema are pleural effusion with macroscopic presence of pus, a positive Gram stain or culture of pleural fluid, or a pleural fluid pH under 7.2 with normal peripheral blood ph.

Primary hyperaldosteronism, also known as Conn’s Syndrome, is one of the most common causes of secondary hypertension (HTN).
The common clinical scenarios in which the possibility of primary hyperaldosteronism should be considered include the following:
– Patients with spontaneous or unprovoked hypokalaemia, especially if the patient is also hypertensive
– Patients who develop severe and/or persistent hypokalaemia in the setting of low to moderate doses of potassium-wasting diuretics
– Patients with treatment-refractory/-resistant hypertension (HTN)
Patients with severe hypokalaemia report fatigue, muscle weakness, cramping, headaches, and palpitations. They can also have polydipsia and polyuria from hypokalaemia-induced nephrogenic diabetes insipidus. Long-standing HTN may lead to cardiac, retinal, renal, and neurologic problems, with all the associated symptoms and signs.

Diabetic peripheral neuropathy usually goes in parallel with retinopathy and nephropathy. It is also slowly progressive and affects mainly the spinothalamic pathway.
Alcohol induced peripheral neuropathy is also slowly progressive and affects mainly the spinothalamic pathway.
Vitamin B 12 deficiency usually causes a more rapidly progressive neuropathy with dorsal column involvement (joint position and vibration involvement with sensory ataxia and pseudoathetosis of upper limbs).

The symptoms of ataxia, slurred speech and blurred vision are all suggestive of phenytoin toxicity. Cimetidine increases the efficacy of phenytoin by reducing its hepatic metabolism.

Phenytoin has a narrow therapeutic index (10-20 mg/L) and its levels are monitored by measuring the total phenytoin concentration.
Cimetidine is an H2 receptor antagonist used in the treatment of peptic ulcers. It acts by decreasing gastric acid secretion.
Cimetidine also has an inhibitory effect on several isoforms of the cytochrome enzyme system including the CYP450 enzymatic pathway. Phenytoin is metabolized by the same cytochrome P450 enzyme system in the liver.
Thus, the simultaneous administration of both these medications leads to an inhibition of phenytoin metabolism and thus increases its circulating levels leading to phenytoin toxicity.

Cisplatin is a cytotoxic agent that acts by causing cross-linking in DNA. Its adverse effects include ototoxicity, peripheral neuropathy, hypomagnesaemia, etc.

The causative cytotoxic agents acting through the other aforementioned MOAs are as follows:

1. Doxorubicin: Stabilizes DNA topoisomerase II complex and inhibits DNA and RNA synthesis.

2. Hydroxyurea (hydroxycarbamide): Inhibits ribonucleotide reductase, decreasing DNA synthesis.

3. Mercaptopurine (6-MP): Purine analogue that is activated by HGPRTase, decreasing purine synthesis.

4. Vincristine, vinblastine: Inhibits formation of microtubules.

Normal pO2 but decreased oxygen saturation is characteristic of methemoglobinemia.

Methemoglobinemia is a rare condition in which the haemoglobin iron is in oxidized or ferric state (Fe3+) and cannot reversibly bind oxygen. Normally, the conversion of ferrous form of iron (Fe2+) to its ferric form (Fe3+) is regulated by NADH methaemoglobin reductase, which results in the reduction of methaemoglobin to haemoglobin. Disruption in the enzyme leads to increased methaemoglobin in the blood. There is tissue hypoxia as Fe3+ cannot bind oxygen, and hence the oxygen-haemoglobin dissociation curve is shifted to the left.

Methemoglobinemia can occur due to congenital or acquired causes. Congenital causes include haemoglobin variants such as HbM and HbH, and deficiency of NADH methaemoglobin reductase. Acquired causes are drugs (e.g. sulphonamides, nitrates, dapsone, sodium nitroprusside, and primaquine) and chemicals (such as aniline dyes).

The features of methemoglobinemia are cyanosis, dyspnoea, anxiety, headache, severe acidosis, arrhythmias, seizures, and loss of consciousness. Patients have normal pO2 but oxygen saturation is decreased. Moreover, presence of chocolate-brown coloured arterial blood (colour does not change with addition of O2) and brown urine also point towards the diagnosis of methemoglobinemia.

The history is suggestive of scleroderma renal crisis, where we would expect thrombotic microangiopathy process with vascular endothelium involvement manifesting as mucoid intimal thickening or onion skin effect.

Digoxin acts by inhibiting the Na+/K+ ATPase pump.
Digoxin is a cardiac glycoside now mainly used for rate control in the management of atrial fibrillation. As it has positive inotropic properties it is sometimes used for improving symptoms (but not mortality) in patients with heart failure.

Mechanism of action:
It decreases the conduction through the atrioventricular node which slows the ventricular rate in atrial fibrillation and atrial flutter.
It increases the force of cardiac muscle contraction due to inhibition of the Na+/K+ ATPase pump. It also stimulates the vagus nerve.

Digoxin toxicity:
Plasma concentration alone does not determine whether a patient has developed digoxin toxicity. The likelihood of toxicity increases progressively from 1.5 to 3 mcg/l.
Clinical feature of digoxin toxicity include a general feeling of unwell, lethargy, nausea & vomiting, anorexia, confusion, xanthopsia, arrhythmias (e.g. AV block, bradycardia), and gynaecomastia

Precipitating factors:
Hypokalaemia
Increasing age
Renal failure
Myocardial ischemia
Hypomagnesaemia, hypercalcemia, hypernatremia, acidosis
Hypoalbuminemia
Hypothermia
Hypothyroidism
Drugs: amiodarone, quinidine, verapamil, diltiazem, spironolactone (competes for secretion in the distal convoluted tubule, therefore, reduce excretion), ciclosporin. Also, drugs that cause hypokalaemia e.g. thiazides and loop diuretics.

Management of digoxin toxicity:
Digibind
Correct arrhythmias
Monitor and maintain potassium levels within the normal limits.

The patient has primary Hypogonadism.
Since he already had two children, Klinefelter syndrome is excluded and the patient does not need karyotyping.
His lab results are normal indicating normal pituitary gland functions.
So the next step is testicular ultrasound as testicular tumour, infiltration or idiopathic failure is suspected.

The history is suggestive of hypertrophic obstructive cardiac myopathy. The degree of left ventricular hypertrophy is strongly associated with sudden cardiac death.

Given that he has diverticula in the clinical scenario combined with his presenting symptoms, it is likely that he has diverticular disease. A low fibre diet would support this diagnosis. Acute diverticulitis would require treatment with antibiotics. Depending on the severity (Hinchey classification) would determine if he needs oral or IV antibiotics, hospital admission or outpatient treatment. Sometimes abscesses or micro perforations occur, which typical require drainage and possibly surgical intervention. Diverticular disease is clearly a better answer than other possible answer choices, simply based on the symptoms presented in the prompt (and mention of low fibre).

The hazard ratio describes the relative risk of the complication based on comparison of event rates.

Hazard ratios have also been used to describe the outcome of therapeutic trials where the question is to what extent treatment can shorten the duration of the illness. However, the hazard ratio, a type of relative risk, does not always accurately portray the degree of abbreviation of the illness that occurred. In these circumstances, time-based parameters available from the time-to-event curve, such as the ratio of the median times of the placebo and drug groups, should be used to describe the magnitude of the benefit to the patient. The difference between hazard-based and time-based measures is analogous to the odds of winning a race and the margin of victory. The hazard ratio is the odds of a patient’s healing faster under treatment but does not convey any information about how much faster this event may occur.

An escharotomy is a surgical procedure used to treat full-thickness (third-degree) circumferential burns. In full-thickness burns, both the epidermis and the dermis are destroyed along with sensory nerves in the dermis. The tough leathery tissue remaining after a full-thickness burn has been termed eschar.

In myasthenia gravis, repeated muscle contractions lead to reduced muscle strength. The opposite is however classically seen in the related disorder Lambert-Eaton syndrome. Lambert-Eaton myasthenic syndrome is seen in association with small cell lung cancer, and to a lesser extent breast and ovarian cancer. It may also occur independently as an autoimmune disorder. Lambert-Eaton myasthenic syndrome is caused by an antibody directed against pre-synaptic voltage gated calcium channel in the peripheral nervous system.

Anti ds-DNA antibodies are very specific for SLE and their presence most often indicates systemic spread of the disease. These antibodies are present in about 30 percent of the total cases of SLE.

Flashes and floaters are symptoms of vitreous detachment. The patient is at risk of retinal detachment and should be referred urgently to an ophthalmologist.

The most common causes of a sudden painless loss of vision are as follows:
– Ischaemic optic neuropathy (e.g. temporal arteritis or atherosclerosis)
– Occlusion of central retinal vein
– Occlusion of central retinal artery
– Vitreous haemorrhage
– Retinal detachment

The patient has hyperthyroidism and its most common cause is Grave’s Disease.
Grave’s Disease is an autoimmune disease due to circulating autoantibodies known as TSH receptor stimulating autoantibodies or Thyroid-stimulating immunoglobulins (TSIs) that bind to and activate thyrotropin receptors, causing the thyroid gland to grow and the thyroid follicles to increase the synthesis of thyroid hormone.

Idiopathic pulmonary fibrosis (IPF) is a condition in which the lungs become scarred and breathing becomes increasingly difficult.
The most common signs and symptoms of idiopathic pulmonary fibrosis are shortness of breath and a persistent dry, hacking cough. Many affected individuals also experience a loss of appetite and gradual weight loss.

The clinical findings of IPF are bibasilar reticular abnormalities, ground glass opacities, or diffuse nodular lesions on high-resolution computed tomography and abnormal pulmonary function studies that include evidence of restriction (reduced VC with an increase in FEV1/FVC ratio) and/or impaired gas exchange (increased P(A-a)O2 with rest or exercise or decreased diffusion capacity of the lung for carbon monoxide [DLCO]).

An aspergilloma is a fungus ball (mycetoma) that develops in a pre-existing cavity in the lung parenchyma. Underlying causes of the cavitary disease may include treated tuberculosis or other necrotizing infection, sarcoidosis, cystic fibrosis, and emphysematous bullae. The ball of fungus may move within the cavity but does not invade the cavity wall. Aspergilloma may manifest as an asymptomatic radiographic abnormality in a patient with pre-existing cavitary lung disease due to sarcoidosis, tuberculosis, or other necrotizing pulmonary processes. In patients with HIV disease, aspergilloma may occur in cystic areas resulting from prior Pneumocystis jiroveci pneumonia. Of patients with aspergilloma, 40-60% experience haemoptysis, which may be massive and life threatening. Less commonly, aspergilloma may cause cough and fever.

Live virus vaccines include: Vaccinia (smallpox), Measles, Mumps, Rubella (MMR combined vaccine), Varicella (chickenpox), Influenza (nasal spray), Rotavirus, Zoster (shingles) and Yellow fever. Inactivated vaccines are Polio (IPV), Hepatitis A and Rabies.

Difficulty in initiating movement (bradykinesia), postural instability and unilateral symptoms (initially) are typical of Parkinson’s. Essential tremor symptoms are usually worse if arms are outstretched and eased by rest and alcohol.

Philadelphia translocation, t(9;22), is a marker of poor prognosis in acute lymphoblastic leukaemia (ALL).

ALL is the malignancy of lymphoid progenitor cells affecting B or T cell lineage. This results in the arrest of lymphoid cell maturation and proliferation of immature blast cells (lymphoblasts), leading to bone marrow and tissue infiltration.

ALL is the most common type of childhood cancers. Its peak incidence is between two to three years of age.

Acute B lymphoblastic leukaemia (B-ALL) is the most common type of ALL, involving overproduction of B-cell lymphoblasts. It is manifested by low initial WCC and is associated with a good prognosis.

Poor prognostic factors for ALL include:
1. Pre-B cell or T-cell ALL (T-ALL)
2. Philadelphia translocation, t(9;22)
3. Age <2 years or >10 years
4. Male sex
5. CNS involvement
6. High initial WBC (e.g. >100 x 10^9/L)
7. non-Caucasian

Downbeat nystagmus (DBN) suggests a lesion in the lower part of the medulla. Arnold-Chiari malformation usually presents with symptoms due to brainstem and lower cranial nerve dysfunction such as DBN.

This is most likely describing irritable bowel syndrome (IBS). Symptoms are either diarrhoea, constipation, or both, abdominal pain, bloating, with various durations. It is a functional, not organic, problem, as far as research shows at this point. It is essentially a diagnosis of exclusion. Treatment is a high fibre diet with fluids. Caffeine should be avoided as this can worsen symptoms. Full colonoscopy is not warranted at this time, neither is a barium enema. A wheat-free diet is not likely to help as there is no evidence they have an allergy to this.

A fasting blood glucose level from 110 to 126 mg/dL (5.5 to 6.9 mmol/L) is considered prediabetes. This result is sometimes called impaired fasting glucose.
Diabetes mellitus (type 2): diagnosis

The diagnosis of type 2 diabetes mellitus can be made by plasma glucose. If the patient is symptomatic:
fasting glucose greater than or equal to 7.0 mmol/l
random glucose greater than or equal to 11.1 mmol/l (or after 75g oral glucose tolerance test)
If the patient is asymptomatic the above criteria apply but must be demonstrated on two separate occasions.

Meningiomas are the most common benign tumours of the brain. Their name is derived from the fact that they arise from the dura mater which together with the pia matter and arachnoid mater form the meninges. The chances that a meningioma is benign are almost 98%. They are non-invasive and well delineated, causing sign and symptoms of brain compression.

Autosomal recessive polycystic kidney disease (ARPKD) is less common than ADPKD (dominant form) but can already present with symptoms and be diagnosed on prenatal ultrasound.

Acyclovir is the correct answer. There has been no documented evidence of harm in pregnancy yet. Chickenpox can cause fetal abnormalities, and varicella zoster Immunoglobulin should be given to the infant immediately after birth (not the mother, won’t help). Steroids will actually make the chicken pox worse. Painkillers only, is obviously the wrong answer and pose severe risk to foetus.

Lateral epicondylitis (tennis elbow) is an overuse injury of the hand and finger extensor tendons that originate in the lateral humeral epicondyle that occurs following repeated or excessive pronation/supination and extension of the wrist (e.g., in racquet sports). Clinical features include pain and tenderness over the lateral epicondyle and along extensor muscles, thickening of the tendons. The examiner holds the patient’s hand with the thumb placed over the lateral epicondyle – The patient makes a fist, supinates the forearm, deviates radially, and extends the fist against the examiner’s resistance which results in pain over the lateral epicondyle. Conservative treatment includes rest, physiotherapy and orthotic braces. If this fails corticosteroids and lidocaine injections are employed. Surgery is indicated in patients with persistent symptoms despite 6 months of conservative treatment. Excision of abnormal tendon tissue; longitudinal incisions (tenotomies) in scarred and fibrotic areas to promote healing.

Sarcoidosis is an inflammatory disease that affects one or more organs but most commonly affects the lungs and lymph glands. The inflammation may change the normal structure and possibly the function of the affected organ(s).
The presentation in sarcoidosis varies with the extent and severity of organ involvement, as follows:
Asymptomatic (incidentally detected on chest imaging): Approximately 5% of cases.
Systemic complaints (fever, anorexia): 45% of cases
Pulmonary complaints (dyspnoea on exertion, cough, chest pain, and haemoptysis [rare]): 50% of cases

Löfgren syndrome (fever, bilateral hilar lymphadenopathy, and polyarthralgias): Common in Scandinavian patients, but uncommon in African-American and Japanese patients.

Dermatologic manifestations may include the following:
– Erythema nodosum
– A lower-extremity panniculitis with painful, erythematous nodules (often with Löfgren syndrome)
– Lupus pernio (the most specific associated cutaneous lesion)
– Violaceous rash on the cheeks or nose (common)
– Maculopapular plaques (uncommon)

Staging of sarcoidosis is as follows:
Stage 0: Normal chest radiographic findings
Stage I: Bilateral hilar lymphadenopathy
Stage II: Bilateral hilar lymphadenopathy and infiltrates
Stage III: Infiltrates alone
Stage IV: Fibrosis

Nonsteroidal anti-inflammatory drugs (NSAIDs) are indicated for the treatment of arthralgias and other rheumatic complaints. Patients with stage I sarcoidosis often require only occasional treatment with NSAIDs.

Treatment in patients with pulmonary involvement is as follows:
Asymptomatic patients may not require treatment
In patients with minimal symptoms, serial re-evaluation is prudent
Treatment is indicated for patients with significant respiratory symptoms
Corticosteroids can produce small improvements in the functional vital capacity and in the radiographic appearance in patients with more severe stage II and III disease.

This patient has Stage 1 Sarcoidosis so observation is the most appropriate action.

This man is likely suffering from a subarachnoid haemorrhage or intracerebral bleed. The priority is to prevent a secondary brain injury. Important first steps include ensuring a secure airway, normalizing cardiovascular function, and treating seizures. His airway is likely to be protected with a GCS of 9, although he may benefit from a nasal or oral airway, and close attention should be paid to his airway if going for a CT scan. He should receive high flow oxygen and his blood pressure should not be treated acutely, as i is often appropriate to compensate for a rise in intracranial pressure. Nimodipine should be given if a subarachnoid haemorrhage is proven. Attention should also be given to maintaining a normal blood sugar, as hyperglycaemia worsens outcomes.

The typical “rheumatoid effusion” is a sterile exudative fluid with low pH (<7.3), low glucose (<60 mg. dL−1) and elevated lactate dehydrogenase (may be >700 IU). It should initially be treated with NSAIDs. Decortication should be reserved in patients with thickened pleura who have symptomatic dyspnoea.

Cryoglobulinemia may be caused by paraprotein bands such as those seen in Waldenström’s macroglobulinemia and multiple myeloma (MM). Meltzer’s triad of arthralgia, weakness, and palpable purpura are common to all types of cryoglobulinemia—as are membranoproliferative glomerulonephritis and low C4 levels. Raynaud’s phenomenon, however, occurs only in type 1 cryoglobulinemia, and its presence can be helpful in ascertaining the underlying cause.

Cryoglobulinemia is a condition in which the blood contains large amounts of pathological cold-sensitive antibodies called cryoglobulins—proteins (mostly immunoglobulins themselves) that become insoluble at reduced temperatures. One-third of the cases are idiopathic.

There are three types of cryoglobulinemia:
1. Type I (25%):
Monoclonal—IgG or IgM
Associated with multiple myeloma (MM), Waldenström’s macroglobulinemia

2. Type II (25%):
Mixed monoclonal and polyclonal—usually with rheumatoid factor (RF)
Associated with hepatitis C, rheumatoid arthritis (RA), Sjogren’s syndrome

3. Type III (50%):
Polyclonal—usually with RF
Associated with rheumatoid arthritis, Sjogren’s syndrome

Investigation results for cryoglobulinemia show low complement (especially C4) and high ESR. Treatment options include immunosuppression and plasmapheresis.

The total daily morphine dose is 30 x 2 = 60 mg. Therefore, the breakthrough dose should be one-sixth of this, 10 mg.

Night sweats are a B symptom in Hodgkin lymphoma (HL) and imply a poor prognosis.

HL is a malignant proliferation of lymphocytes characterised by the presence of distinctive giant cells known as Reed-Sternberg cells. It has a bimodal age distribution being most common in the third and seventh decades of life.

Staging of HL is done according to the Ann Arbor staging system:

Stage
I: Single lymph node region (I) or one extra lymphatic site (IE)

II: Two or more lymph node regions on same side of the diaphragm (II) or local extra lymphatic extension plus one or more lymph node regions on same side of the diaphragm (IIE)

III: Lymph node regions on both sides of the diaphragm (III) which may be accompanied by local extra lymphatic extension (IIIE)

IV: Diffuse involvement of one or more extra lymphatic organs or sites

Suffix
A: No B symptoms

B: Presence of at least one of the following: unexplained weight loss >10% baseline during 6 months before staging; recurrent unexplained fever >38°C; recurrent night sweats—poor prognosis.

History of recurrent infections and failure to thrive (probably due to pancreatic enzyme insufficiency) is highly suggestive of cystic fibrosis. Pseudomonas has been identified as an important respiratory pathogen in patients with cystic fibrosis.

Topical benzoyl peroxide is used for the treatment of mild to moderate acne vulgaris. It is actually a peeling agent and it clears the pores and reduces the bacterial cell count.

Insulin/dextrose infusion will increase the activity of the sodium-potassium pump in the cells, which will in turn decrease serum potassium levels.

Of all the listed options, gastric cancer is least likely to be inherited.

The above mentioned tumours are ruled out as explained below:
1. Breast and Ovarian cancers: Between 5%–10% of all breast cancers are thought to be hereditary. Mutation in the BRCA1 and BRCA2 genes also increase the risk of ovarian cancer.

2. Colorectal and Endometrial cancers: About 5% of cases of colorectal cancer are caused by hereditary non-polyposis colorectal carcinoma (HNPCC) and 1% are due to familial adenomatous polyposis. Women who have HNPCC also have a markedly increased risk of developing endometrial cancer—around 5% of endometrial cancers occur in women with this risk factor.

Deletion of part of chromosome 5 or 7 is a poor prognostic feature for acute myeloid leukaemia (AML).

AML is the acute expansion of the myeloid stem line, which may occur as a primary disease or follow the secondary transformation of a myeloproliferative disorder. It is more common over the age of 45 and is characterized by signs and symptoms largely related to bone marrow failure such as anaemia (pallor, lethargy), frequent infections due to neutropenia (although the total leucocyte count may be very high), thrombocytopaenia (bleeding), ostealgia, and splenomegaly.

The disease has poor prognosis if:
1. Age of the patient >60 years
2. >20% blasts seen after the first course of chemotherapy
3. Chromosomal aberration with deletion of part of chromosome 5 or 7.

Acute promyelocytic leukaemia (APL) is an aggressive form of AML.

Cephalosporins, such as ceftriaxone, do not cover methicillin-resistant staph aureus. They do cover some gram positives and gram negatives. Vancomycin and teicoplanin given intravenously have good coverage of MRSA and other gram positive bacteria. Rifampicin and doxycycline, although not the best treatment, can be used for outpatients if there are no systemic signs of illness.

The upper motor neurone signs in this patient point towards a diagnosis of spinal cord compression above the level of L1 and rules out cauda equina syndrome.

Spinal cord compression is an oncological emergency and affects up to 5% of cancer patients. Extradural compression accounts for the majority of cases, usually due to vertebral body metastases. One of the most common causes of spinal cord compression is osteoarthritis. It is also more commonly seen in patients with lung, breast, or prostate cancer.

Clinical features include:
1. Back pain: the earliest and most common symptom, may worsen on lying down or coughing
2. Lower limb weakness
3. Sensory changes: sensory loss and numbness
4. Neurological signs: depending on the level of the lesion.
Lesions above L1 usually result in upper motor neurone signs in the legs. Lesions below L1 usually cause lower motor neurone signs in the legs and perianal numbness. Tendon reflexes are increased below the level of the lesion and absent at the level of the lesion.

Management options are:
1. High-dose oral dexamethasone
2. Urgent MRI for consideration of radiotherapy or surgery

Causes for ST segment elevation other than myocardial infarction
Natural variants
-Early repolarization
-Left ventricular hypertrophy and hypertrophic cardiomyopathy
-Left bundle branch block
Artefacts
-Leads mispositioning
-Electrical cardioversion
Cardiovascular diseases
-Pericarditis/ Myocarditis
-Aortic dissection
-Prinzmetal’s angina
-Takotsubo Cardiomyopathy
-Brugada Syndrome and arrhythmogenic right ventricular cardiomyopathy/dysplasia
Pulmonary diseases
-Pulmonary thromboembolism
-Pneumothorax
-Atelectasis and pulmonary metastases
Gastrointestinal diseases
-Acute pancreatitis
-Acute cholecystitis
Other conditions
-Hyperkalaemia
-Drug induced ST segment elevation (e.g. – clozapine)
-Haemorrhagic cerebrovascular disease

Coronary artery disease and myocardial infarction can be excluded with a negative angiogram and a slightly elevated troponin. Hypertrophic cardiomyopathy can be excluded with cardiovascular MR findings. Left ventricular aneurysm usually occurs following a myocardial infarction, but there is no positive history for that. The characteristic findings on cardiovascular MR confirms the diagnosis of Takotsubo cardiomyopathy.

Motor neuron disease is a neurological condition of unknown cause which can present with both upper and lower motor neuron signs. It rarely presents before age 40 and various patterns of disease are recognised, including amyotrophic lateral sclerosis, progressive muscular atrophy and bulbar palsy.
Non-invasive ventilation (usually BIPAP) is used at night, with studies having shown a survival benefit of around 7 months. Riluzole prevents stimulation of glutamate receptors, used mainly in amyotrophic lateral sclerosis and has been shown to prolong life by about 3 months.

Drug metabolism can be broadly classified into:
Phase I (functionalization) reactions: also termed non-synthetic reactions, they include oxidation, reduction, hydrolysis, cyclization and de-cyclization. The most common and vital reactions are oxidation reactions. (Of the given enzymes only Alcohol dehydrogenase is involved in phase I drug metabolism. Succinate dehydrogenase, is a vital enzyme involved in the Kreb’s cycle and the mitochondrial electron transport chain). They are mainly catalysed by Cytochrome P-450 enzyme.

Phase II (conjugation) reactions: occur following phase I reactions, they include reactions: glucuronidation and sulphate conjugation, etc. They are mostly catalysed by UDP-glucuronosyltransferase enzyme. Other phase II enzymes include: sulfotransferases, N-acetyltransferases, glutathione S-transferases and methyltransferases.