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

Activated charcoal is useful if given within one hour of the paracetamol overdose. Liver function tests, INR and prothrombin time will be normal, as liver damage may not manifest until 24 hours or more after ingestion.

The antidote of choice is intravenous N-acetylcysteine, which provides complete protection against toxicity if given within 10 hours of the overdose.

A Mongolian spot can be present in new born babies which usually appears over the back and fades with time. There is nothing to worry about.

Supravalvular aortic stenosis, is associated with a condition called William’s syndrome.
William’s syndrome is an inherited neurodevelopmental disorder caused by a microdeletion on chromosome 7. The most common symptoms of Williams syndrome are heart defects and unusual facial features. Other symptoms include failure to gain weight appropriately in infancy (failure to thrive) and low muscle tone. Individuals with Williams syndrome tend to have widely spaced teeth, a long philtrum, and a flattened nasal bridge.
Most individuals with Williams syndrome are highly verbal relative to their IQ, and are overly sociable, having what has been described as a cocktail party type personality.

Dermatitis herpetiformis (DH), or Duhring’s disease, is a chronic blistering skin condition,characterised by blisters filled with a watery fluid. Despite its name, it is neither related to nor caused by herpes virus: the name means that it is a skin inflammation having an appearance similar to herpes.
Dermatitis herpetiformis is characterized by intensely itchy, chronic papulovesicular eruptions, usually distributed symmetrically on extensor surfaces (buttocks, back of neck, scalp, elbows, knees, back, hairline, groin, or face)
Dermatitis herpetiformis is an autoimmune condition associated with HLA-DR3.
HLA-A3 is associated with haemochromatosis. HLA-B5 is most commonly associated with Behcet’s disease. HLA-DR4 is associated with both type 1 diabetes mellitus and rheumatoid arthritis. HLA-B27 is most commonly associated with several diseases, most commonly ankylosing spondylitis.

The classic history in this high risk patient is suggestive of a dissecting aortic aneurysm. His transoesophageal echocardiogram confirms the diagnosis. ST elevation in ECG is probably due to the extension of the dissection of the aorta which results in compromised coronary blood supply.

For medical management of carcinoid syndrome, there are two somatostatin analogues available, Octreotide and Lanreotide. Somatostatin is an amino acid peptide which is an inhibitory hormone, which is synthesized by paracrine cells located ubiquitously throughout the gastrointestinal tract. Both somatostatin analogues provide symptom relief in 50% to 70% of patients and biochemical response in 40% to 60% patients. Many studies have shown that Octreotide and Lanreotide also inhibit the proliferation of tumour cells.

Prolactinomas, benign lesions that produce the hormone prolactin, are the most common hormone-secreting pituitary tumours.
Based on its size, a prolactinoma can be classified as a microprolactinoma (< 10 mm diameter) or a macroprolactinoma (>10 mm diameter). If the prolactinoma is large enough to compress the surrounding normal hormone-secreting pituitary cells, it may result in deficiencies of one or more hormones (e.g., thyroid-stimulating hormone [TSH], growth hormone [GH], adrenocorticotropic hormone). However, the patient has microadenoma so it is unlikely to cause compression manifestations.
Hyperprolactinemia inhibits GnRH secretion from the medial basal hypothalamus and LH release from the pituitary.

Rasburicase is a recombinant version of urate oxidase which is an enzyme that metabolizes uric acid to allantoin.

TLS is a potentially fatal condition occurring as a complication during the treatment of high-grade lymphomas and leukaemias. It occurs from the simultaneous breakdown (lysis) of the tumour cells and subsequent release of chemicals into the bloodstream. This leads to hyperkalaemia and hyperphosphatemia in the presence of hyponatraemia. TLS can occur in the absence of chemotherapy, but it is usually triggered by the introduction of combination chemotherapy. Awareness of the condition is critical for its prophylactic management.

Patients at high risk of TLS should be given IV rasburicase or IV allopurinol immediately prior to and during the first few days of chemotherapy. Allantoin is much more water soluble than uric acid and is therefore more easily excreted by the kidneys. Patients in lower-risk groups should be given oral allopurinol during cycles of chemotherapy in an attempt to avoid the condition.

TLS is graded according to the Cairo-Bishop scoring system as:
1. Laboratory tumour lysis syndrome
2. Clinical tumour lysis syndrome

A grossly elevated APTT may be caused by heparin therapy, haemophilia, or antiphospholipid syndrome. A normal factor VIIIc activity, however, points towards the diagnosis of haemophilia B, which is the deficiency of factor IX in the blood.

Haemophilia is an X-linked recessive disorder of coagulation. Up to 30% of patients have no family history of the condition. Haemophilia A is due to the deficiency of clotting factor VIII and is more common than haemophilia B, accounting for 90% of the cases. In haemophilia B (Christmas disease), there is a deficiency of clotting factor IX.

Characteristic features of haemophilia include hemarthrosis, haematomas, and prolonged bleeding following trauma or surgery. Coagulation profile of a haemophiliac person shows prolonged bleeding time, activated partial thromboplastin time (APTT), thrombin time (TT), but a normal prothrombin time (PT).

Leptin, a 167–amino acid hormone, was discovered in 1994 and is secreted mainly by adipocytes. Plasma leptin levels are significantly correlated with body mass index (BMI) and the total amount of body fat.

The next step in managing this patient is to give 10 mg and continue administering in 10 mg increments each hour until symptoms are under control.

Methadone alleviates opioid withdrawal symptoms and reduces cravings. Methadone is useful for detoxification from longer-acting opioids such as morphine or methadone itself.
Methadone should be used with caution if the patient has:
Respiratory deficiency
Acute alcohol dependence
Head injury
Treatment with monoamine oxidase inhibitors (MAOIs)
Ulcerating colitis or Crohn’s disease
Severe hepatic impairment
The dose must be reviewed on a daily basis and adjusted based upon how well the symptoms are controlled and the presence of side effects. The greater the dose of opioids used by the patient, the greater the dose of methadone required to control withdrawal symptoms.

To avoid the risk of overdose in the first days of treatment The recommended dosing of methadone is 30mg in two doses of 15mg morning and evening.

It is important to note that a methadone dose equivalent to what the patient reports they are taking should never be given.
It is rare to need more than 40 mg per 24 hours: beware of overdosing which can lead to respiratory arrest.

The presentation of the patient is typical of chronic lithium toxicity (due to the presence of mainly neurological manifestations). Additional to the blood investigations mentioned, urine analysis, electrolyte levels, and renal function should also be performed. A low urine Anion gap and a low urine specific gravity are highly suggestive of lithium toxicity.
ECG obtained in this patient is likely to show: nonspecific, diffuse ST segment depression with T wave inversion.
Acute lithium toxicity presents with more GI manifestations while, the clinical features of chronic lithium toxicity are mainly neurological and can include:
Coarse tremors (fine tremors are seen in therapeutic levels), hyperreflexia, acute confusion, seizures, and coma.
The management of lithium toxicity is as follows:
Immediate GI decontamination with gastric lavage (in case of acute intoxication)
Saline Administrations: the goal of saline administration is to restore GFR, normalize urine output and enhance lithium clearance.
Haemodialysis remains the mainstay treatment for lithium toxicity as lithium is readily dialyzed because of water solubility, low volume of distribution, and lack of protein binding.
The Extracorporeal Treatments in Poisoning Workgroup (EXTRIP Workgroup) recommendations for dialysis (extracorporeal treatment) in lithium toxicity include:
• Impaired kidney function and lithium levels > 4.0 mEq/L
• Decreased consciousness, seizures, or life-threatening dysrhythmias, regardless of lithium levels
• Levels are > 5.0 mEq/L, significant confusion is noted, or the expected time to reduce levels to < 1.0 mEq/L is more than 36 hours
As post-dialysis rebound elevations in lithium levels have been documented, continuous veno-venous hemofiltration (CVVH) has been advocated.

Sickle cell anaemia is characterised by periods of good health with intervening crises. One of the main types is aplastic crisis characterised by a sudden fall in haemoglobin without marked reticulocytosis (3%—in this case—is just above the normal range). It usually occurs secondary to parvovirus infection.

The other main types of sickle cell crises are thrombotic crisis (painful or vaso-occlusive crisis), sequestration crisis, and haemolytic crisis. Thrombotic crisis is precipitated by infection, dehydration, alcohol, change in temperature, and deoxygenation. Sequestration crisis is characterised by acute chest syndrome (i.e. fever, dyspnoea, chest/rib pain, low pO2, and pulmonary infiltrates). In haemolytic crisis, fall in haemoglobin occurs secondary to haemolysis. It is a rare type of sickle cell crises.

Moxonidine and alpha-methyl dopa are centrally acting antihypertensives and modify blood pressure through modifying sympathetic activity.

Other options:
Verapamil is a calcium antagonist.
Minoxidil and hydralazine are both vasodilators.
Phenoxybenzamine is an alpha-blocker.

Adverse effects:
Dry mouth and somnolence were the most frequently reported adverse events, followed by headache, dizziness, nausea and allergic skin reactions.

NICE now recommends the three acetylcholinesterase inhibitors (donepezil, galantamine and rivastigmine) as options for managing mild to moderate Alzheimer’s disease. Memantine is reserved for patients with moderate to severe Alzheimer’s.

Bradycardia and miosis should be anticipated following the administration of anticholinesterases.

Anticholinesterase agents include the following medications:
– Pyridostigmine, neostigmine, and edrophonium which play a significant role in the diagnosis and the management of myasthenia gravis.
– Rivastigmine, galantamine and donepezil are cholinesterase inhibitors found to be significantly useful in the management of Alzheimer’s disease.

Mechanism of action and pharmacological effects:
Inhibition of cholinesterase increases the level and the duration of action of acetylcholine within the synaptic cleft.

Thus, cholinergic effects such as a reduction in heart rate (bradycardia), miosis (pupillary constriction), increased secretions, increased gastrointestinal motility and reduction in BP may occur with anticholinesterases.

Toxins such as organophosphates and carbamates also are primarily anticholinergic and cause the following typical SLUDGE symptoms:
– Salivation
– Lacrimation
– Urination
– Diaphoresis
– Gastrointestinal upset
– Emesis

Waldenström’s macroglobulinemia (also called lymphoplasmacytic lymphoma) is an uncommon type of non-Hodgkin lymphoma seen in older people. It is a lymphoplasmacytoid malignancy characterised by the secretion of a monoclonal IgM paraprotein. Its features include weight loss and lethargy; monoclonal IgM paraproteinemia; hyperviscosity syndrome leading to bilateral central retinal vein occlusion (CRVO) and hence, visual disturbances; hepatosplenomegaly and lymphadenopathy; and cryoglobulinemia. It is not, however, associated with bone pain.

Inherited metabolic disorders are often characterized by the lack of an essential enzyme and are currently treated by dietary restriction and other strategies to replace the substrates or products of the missing enzyme. Patients with homocystinuria lack the enzyme cystathionine β-synthase (CBS), and many of these individuals do not respond to current treatment protocols.

The question describes an alcohol abusing man with chronic epigastric discomfort, radiating into his back, worse with meals, and foul-smelling stools, weight loss, as well as chronic nausea. This is likely, thus chronic pancreatitis due to alcohol abuse. Hepatomegaly and peripheral neuropathy secondary to anaemia support the diagnosis of long term alcohol abuse. Bacterial overgrowth may present with diarrhoea and is a less likely diagnosis than pancreatitis. Celiac disease is a less likely diagnosis than pancreatitis, and you would also expect mention of diarrhoea. VIPoma would also likely present with diarrhoea. Cecal carcinoma would more than likely present with blood in the stool.

Subcutaneous (S/C) low-molecular-weight heparin (LMWH) is a preferred anticoagulant in pregnancy. Warfarin is contraindicated due to its teratogenic effects, especially in the first trimester and at term.

Pregnancy is a hypercoagulable state with the majority of VTE incidents occurring in the last trimester.

Hypercoagulability in pregnancy is caused by:
1. Increase in factors VII, VIII, X, and fibrinogen
2. Decrease in protein S
3. Uterus pressing on IVC causing venous stasis in legs

Management options include:
1. S/C LMWH preferred to IV heparin (less bleeding and thrombocytopaenia)
2. Warfarin contraindicated

The number needed to treat (NNT) is an absolute effect measure that has been used to assess beneficial and harmful effects of medical interventions. In this case the NNT can be calculated as follows: NNT = 1/ Absolute risk reduction (ARR). ARR=(Control event rate expressed per 1000 patient years) – (Experimental event rate expressed per 1000 patient years) = 43.9-37.3 = 6.6/1000 patient years

NNT=(Patient years)/ARR = 1000/ 6.6 = 151.5. The closest to 151.5 is 150, thus it is the correct answer.

Contact dermatitis is a red, itchy rash caused by direct contact with a substance or an allergic reaction to it. The entry of allergen into the epidermis or dermis causes a localized allergic reaction. Local mast-cell activation in the skin leads immediately to a local increase in vascular permeability, which causes extravasation of fluid and swelling. Histamine released by mast cells activated by allergen in the skin causes large, itchy, red swellings of the skin.

Hyperacute rejection appears in the first minutes following transplantation and occurs only in vascularized grafts. This very fast rejection is characterized by vessel thrombosis leading to graft necrosis. Hyperacute rejection is caused by the presence of antidonor antibodies existing in the recipient before transplantation. These antibodies induce both complement activation and stimulation of endothelial cells to secrete Von Willebrand procoagulant factor, resulting in platelet adhesion and aggregation. The result of these series of reactions is the generation of intravascular thrombosis leading to lesion formation and ultimately to graft loss. Today, this type of rejection is avoided in most cases by checking for ABO compatibility and by excluding the presence of antidonor human leukocyte antigen (HLA) antibodies by cross-match techniques between donor graft cells and recipient sera. This type of rejection is also observed in models of xenotransplantation of vascularized organs between phylogenetically distant species when no immunosuppressive treatment is given to the recipients.

Downbeat nystagmus (DBN) suggests a lesion in the lower part of the medulla. Chiari Type I malformation usually presents with symptoms due to brain stem and lower cranial nerve dysfunction, which includes DBN.

Carbon monoxide (CO) poisoning:
It is considered as the great imitator of other diseases as the patients present with a myriad of symptoms. The carbon monoxide diffuses rapidly across the pulmonary capillary membrane binding to the haem molecule with a very high affinity (240 times that of oxygen) forming carboxy-haemoglobin (COHb). Non-smokers have a baseline COHb of ,3% while smokers have a baseline COHb of 10-15%.

Clinical features of carbon monoxide toxicity:
Headache: 90% of cases (most common clinical feature)
Nausea and vomiting: 50%
Vertigo: 50%
Confusion: 30%
Subjective weakness: 20%
Severe toxicity: ‘pink’ skin and mucosa, hyperpyrexia, arrhythmias, extrapyramidal features, coma, death
Cherry red skin is a sign of severe toxicity and is usually a post-mortem finding.
Management
• 100% oxygen
• Hyperbaric oxygen therapy (HBOT)

The use of Hyperbaric oxygen therapy (HBOT) for treatment mild to moderate CO poisoning is not routine.
The selection criteria for HBOT in cases of CO poisoning include:
• COHb levels > 20-25%
• COHb levels > 20% in pregnant patient
• Loss of consciousness
• Severe metabolic acidosis (pH <7.1)
• Evidence of end-organ ischemia (e.g., ECG changes, chest pain, or altered mental status)

The history gives you a woman who is on inhaled steroid therapy. It is always a good idea for patients to rinse their mouths well after using inhaled steroids. Odynophagia (pain on swallowing) is a symptom of oesophageal candidiasis, which is the most likely answer given the steroids. Typically, you might see this in someone who is immunocompromised (classically, in HIV+ patients).

Diagnosis of RA is mainly based on clinical features (e.g., morning stiffness, symmetrical joint swelling) and laboratory tests (e.g., anti-CCP). Rheumatoid factor is not very specific for this disease and hence has low reliability. X-ray findings (e.g., soft tissue swelling or joint space narrowing) occur late in the disease and are therefore not typically used for diagnosis.

In hyperkalaemia the ECG will show tall, tented T waves as well as small P waves and widened QRS complexes. 

The most common causes of a sudden painless loss of vision are:
– ischaemic optic neuropathy
– occlusion of central retinal vein or artery
– vitreous haemorrhage
– retinal detachment.
Central retinal artery occlusion is due to thromboembolism (from atherosclerosis) or arteritis (e.g. temporal arteritis). Features include afferent pupillary defects, and a ‘cherry red’ spot on a pale retina.