Paget’s accelerates the remodelling process with old bone breaking down more quickly which disrupts the normal growth process. New bone development eventually adjusts to the faster pace and speeds up on its own. The pace is too fast for healthy bone growth, and the regrowth ends up softer and weaker than normal. The effect of this accelerated process causes bone pain, fractures, and deformities. Since osteosarcoma is a type of bone cancer linked to abnormal bone growth, this makes it a rare but possible complication of Paget’s disease although the chances of developing osteosarcoma are minimal. Fractures are painful and restrict movement whereas this patients pain is gradually developing. Pain associated with osteoarthritis is usually mild to moderate and worsens as the day progresses.

When you hear painless jaundice and weight loss in the same sentence, the first thing you should think is cancer. Likely cholangiocarcinoma here or some other biliary tract obstructing cancer. The first line imaging for this would be MRCP because you’re looking for obstruction– the dilatation of the intra and extrahepatic ducts suggests this. This is less invasive than an ERCP or a liver biopsy. CT C/A/P will likely be needed for staging later but it is asking for the initial test.

Chicken pox in adults may manifest with acute encephalitis, causing the confusional syndrome known as delirium. Blisters on the trunk favour the diagnosis. The trip to Italy however seems unimportant since the incubation period of chicken pox is 10 to 21 days.

Protein-calorie malnutrition is observed in almost 50% of dialysis patients, contributing to increased morbidity and mortality. All the other complications listed can usually be prevented thanks to modern-day dialysis techniques.

Mild deficiencies of 21-hydroxylase or 3-beta-hydroxysteroid dehydrogenase activity may present in adolescence or adulthood with oligomenorrhea, hirsutism, and/or infertility. This is termed nonclassical adrenal hyperplasia.
Late-onset or nonclassical congenital adrenal hyperplasia (NCAH) due to 21-hydroxylase deficiency is one of the most common autosomal recessive disorders. Reported prevalence ranges from 1 in 30 to 1 in 1000. Affected individuals typically present due to signs and symptoms of androgen excess.
Treatment needs to be directed toward the symptoms. Goals of treatment include normal linear growth velocity, a normal rate of skeletal maturation, ‘on-time’ puberty, regular menstrual cycles, prevention of or limited progression of hirsutism and acne, and fertility. Treatment needs to be individualized and should not be initiated merely to decrease abnormally elevated hormone concentrations.
Normal Ultrasound rules out Turner’s syndrome.

Vitamin B12 is mostly used in the body for the development of red blood cells and maintenance of the nervous system. It is actively absorbed in the terminal ileum after binding to the intrinsic factor (IF) which is secreted from the parietal cells of stomach. Moreover, a small amount is also passively absorbed without being bound to IF.

Vitamin B12 deficiency is characterised by sore tongue and mouth, mood disturbances, ataxia, and macrocytic anaemia. Its causes include poor diet, impaired absorption (due to disorders of terminal ileum), pernicious anaemia, and post-gastrectomy. While managing this condition, if the person is also deficient in folic acid, then it is important to treat the B12 deficiency first in order to avoid precipitating subacute combined degeneration of the cord.

CXR, blood, and urine tests should be carried out initially to exclude an underlying malignancy. If these are normal, a CT scan of abdomen and pelvis should be arranged as the patient’s age is >40 years. Antiphospholipid antibodies should also be checked for the first unprovoked DVT/PE. There is no history, however, to support an inherited thrombophilia.

The National Institute for Health and Care Excellence (NICE) published guidelines in 2012 for the investigation and management of DVT. If a patient is suspected of having DVT, a two-level DVT Wells score should be used:

DVT likely: 2 points or more
DVT unlikely: 1 point or less

This system of points is based on the following clinical features:
1. Active cancer (treatment ongoing, within six months, or palliative)—1
2. Paralysis, paresis, or recent plaster immobilisation of the lower extremities—1
3. Recently bedridden for three days or more, or major surgery within 12 weeks requiring general or regional anaesthesia—1
4. Localised tenderness along the distribution of the deep venous system—1
5. Entire leg swollen—1
6. Calf swelling at least three cms larger than the asymptomatic side—1
7. Pitting oedema confined to the symptomatic leg—1
8. Collateral superficial veins (non-varicose)—1
9. Previously documented DVT—1
10. An alternative diagnosis is at least as likely as DVT—2

If two points or more—DVT is ‘likely’
If one point or less—DVT is ‘unlikely’

Management

1. LMWH or fondaparinux should be given initially after a DVT is diagnosed.
2. A vitamin K antagonist such as warfarin should be given within 24 hours of the diagnosis.
3. LMWH or fondaparinux should be continued for at least five days or until the international normalised ratio (INR) is 2.0 or above for at least 24 hours. LMWH or fondaparinux is given at the same time as warfarin until the INR is in the therapeutic range.
4. Warfarin should be continued for at least three months. At three months, clinicians should assess the risks and benefits of extending the treatment.
5. Consider extending warfarin beyond three months for patients with unprovoked proximal DVT if their risk of VTE recurrence is high and there is no additional risk of major bleeding. This essentially means that if there is no obvious cause or provoking factor (surgery, trauma, significant immobility, etc.), it may be implied that the patient has a tendency to thrombose and should be given treatment longer than the normal of three months. In practice, most clinicians give six months of warfarin for patients with an unprovoked DVT/PE.
6. For patients with active cancer, LMWH should be used for six months.

As both malignancy and thrombophilia are obvious risk factors for DVT, therefore, all patients with unprovoked DVT/PE who are not already known to have cancer should undergo the following investigations:
1. Physical examination (guided by the patient’s full history)
2. Chest X-ray
3. Blood tests (full blood count, serum calcium, and liver function tests) and urinalysis
4. Testing for antiphospholipid antibodies
5. Testing for hereditary thrombophilia in patients who have had unprovoked DVT/PE and have a first-degree relative who has a history of DVT/PE.

After the exposure to chickenpox while pregnant, even if the patient is negative for antibodies she requires immunoglobulin to prevent further issues.

The differential diagnosis of bilateral exercise-induced pain would include metabolic muscle disease, lumbar canal stenosis and intermittent claudication. The patient’s age, history and lack of other risk factors make the latter two options unlikely.

The syndrome described is in fact McArdle’s disease (myophosphorylase deficiency). This is a disorder of carbohydrate metabolism. Clinical features of pain and fatigue are precipitated in early exercise, as carbohydrates cannot be mobilized to provide an energy substrate to the muscle. With prolonged exercise, fatty acid metabolism provides energy, and symptoms lessen. The dark urine described is likely to represent myoglobinuria following rhabdomyolysis. Definitive diagnosis of most metabolic muscle diseases relies on muscle biopsy and enzyme analysis.

Mechanism of action of low molecular weight heparin (LMWH):
It inhibits coagulation by activating antithrombin III. Antithrombin III binds to and inhibits factor Xa. In doing so it prevents activation of the final common path; Xa inactivation means that prothrombin is not activated to thrombin, thereby not converting fibrinogen into fibrin for the formation of a clot.

LMHW is a small fragment of a larger mucopolysaccharide, heparin. Heparin works similarly, by binding antithrombin III and activating it. Heparin also has a binding site for thrombin, so thrombin can interact with antithrombin III and heparin, thus inhibiting coagulation.
Heparin has a faster onset of anticoagulant action as it will inhibit not only Xa but also thrombin, while LMWH acts only on Xa inhibition.

Compared to heparin, LMWHs have a longer half-life, so dosing is more predictable and can be less frequent, most commonly once per day.

Dosage and uses:
LMWH is administered via subcutaneous injection. This has long-term implications on the choice of anticoagulant for prophylaxis, for example, in orthopaedic patients recovering from joint replacement surgery, or in the treatment of DVT/PE.

Adverse effects:
The main risk of LMWH will be bleeding. The specific antidote for heparin-induced bleeding is protamine sulphate.
Less commonly it can cause:
Heparin-induced thrombocytopenia (HIT)
Osteoporosis and spontaneous fractures
Hypoaldosteronism
Hypersensitivity reactions

Diseases that cause predominantly sensory loss include diabetes, uraemia, leprosy, alcoholism, vitamin B12 deficiency, and amyloidosis.
Those that cause predominantly motor loss include Guillain-Barre syndrome, porphyria, lead poisoning, hereditary sensorimotor neuropathies, chronic inflammatory demyelinating polyneuropathy, and diphtheria.

Acromegaly occurs due to excessive action of insulin-like growth factor I (IGF-I) after the growth plate cartilage fuses in adulthood.
It can be an insidious disease. Symptoms, which may precede diagnosis by several years, can be divided into the following groups:
1. Symptoms due to local mass effects of an intracranial tumour
Tumour damage to the pituitary stalk may cause hyperprolactinemia (Increased blood prolactin levels associated with galactorrhoea) due to loss of inhibitory regulation of prolactin secretion by the hypothalamus
2. Symptoms due to excess of GH/IGF-I including:
– Hyperhidrosis (Not hypohidrosis)
– Arthritis
– Peripheral Neuropathies e.g. Carpal Tunnel Syndrome

Brugada syndrome is an autosomal dominant disorder characterized by sudden cardiac death. The positive family history and characteristic ECG findings are in favour of Brugada syndrome. Usually the physical findings are normal.

A case-control study is designed to help determine if an exposure is associated with an outcome (i.e., disease or condition of interest). In theory, the case-control study can be described simply. Case-control studies have specific advantages compared to other study designs. They are comparatively quick, inexpensive, and easy. They are particularly appropriate for (1) investigating outbreaks, and (2) studying rare diseases or outcomes. Sudden infant death syndrome is a rare medical event, thus case-control study is the most suitable option.

This patient has a poorly controlled T2DM with an underlying diabetic nephropathy. The histological findings are Kimmelstiel-Wilson lesions (nodular glomerulosclerosis) and hyaline arteriosclerosis. This is due to nonenzymatic glycosylation.

Diabetic nephropathy is the chronic loss of kidney function occurring in those with diabetes mellitus. Protein loss in the urine due to damage to the glomeruli may become massive, and cause a low serum albumin with resulting generalized body swelling (edema) and result in the nephrotic syndrome. Likewise, the estimated glomerular filtration rate (eGFR) may progressively fall from a normal of over 90 ml/min/1.73m2 to less than 15, at which point the patient is said to have end-stage kidney disease (ESKD). It usually is slowly progressive over years.

The patient most likely suffers from Paget’s disease of the bone as his radiological examination shows both osteolytic and osteosclerotic lesions. Any bone or bones can be affected, but Paget’s disease occurs most frequently in the pelvis > lumbar spine > femur > thoracic spine > sacrum > skull > tibia.

Cyclophosphamide is a cytotoxic alkylating agent that acts by causing cross-linking of DNA strands. Its major adverse effects include haemorrhagic cystitis, myelosuppression, and transitional cell carcinoma.

Cardiomyopathy is caused by doxorubicin and ototoxicity is caused by cisplatin. Alopecia and weight gain are associated with a variety of chemotherapeutic agents especially those that treat breast cancers (e.g. paclitaxel).

The principal mechanism of action of taxanes (e.g. docetaxel) is the prevention of microtubule disassembly.

Other aforementioned options are ruled out because:

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

2. Vincristine, vinblastine: inhibits formation of microtubules.

3. Cisplatin: causes cross-linking in DNA.

Alpha1-antitrypsin (AAT) deficiency, first described in 1963, is one of the most common inherited disorders amongst white Caucasians. Its primary manifestation is early-onset of pan acinar emphysema. In adults, alpha1-antitrypsin deficiency leads to chronic liver disease in the fifth decade. As a cause of emphysema, it is seen in non-smokers in the fifth decade of life and during the fourth decade of life in smokers.

Symptoms of alpha1-antitrypsin (AAT) deficiency emphysema are limited to the respiratory system. Dyspnoea is the symptom that eventually dominates alpha1-antitrypsin deficiency. Similar to other forms of emphysema, the dyspnoea of alpha1-antitrypsin deficiency is initially evident only with strenuous exertion. Over several years, it eventually limits even mild activities.
The serum levels of some of the common genotypes are:
•PiMM: 100% (normal)
•PiMS: 80% of normal serum level of A1AT
•PiSS: 60% of normal serum level of A1AT
•PiMZ: 60% of normal serum level of A1AT, mild deficiency
•PiSZ: 40% of normal serum level of A1AT, moderate deficiency
•PiZZ: 10–15% (severe alpha 1-antitrypsin deficiency)

Finasteride inhibits the formation of dihydrotestosterone.
Finasteride is a 5α-reductase inhibitor and thus, inhibits the conversion of testosterone to dihydrotestosterone (DHT).

DHT is much more active than testosterone and binds more avidly to cytoplasmic receptors. DHT stimulates prostate growth and may be responsible for benign prostatic hyperplasia in the elderly.

Thus, finasteride can cause a reduction in prostatic volume and help in managing a patient with benign prostatic hyperplasia.

The most likely complaint of this patient would be hot flushes.

Alopecia and cataracts are listed in the BNF as possible side-effects. They are however not as prevalent as hot flushes, which are very common in pre-menopausal women.

Tamoxifen is a Selective Oestrogen Receptor Modulator (SERM) which acts as an oestrogen receptor antagonist and partial agonist. It is used in the management of oestrogen receptor-positive breast cancer

Adverse effects:
Menstrual disturbance: vaginal bleeding, amenorrhoea
Hot flushes – 3% of patients stop taking tamoxifen due to climacteric side-effects.
Venous thromboembolism.
Endometrial cancer
Tamoxifen is typically used for 5 years following the removal of the tumour.

Raloxifene is a pure oestrogen receptor antagonist and carries a lower risk of endometrial cancer.

Although antagonistic with respects to breast tissue tamoxifen may serve as an agonist at other sites. Therefore the risk of endometrial cancer is increased cancer.

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 patient likely has celiac’s disease, but if she has been avoiding gluten, a biopsy may be negative. Even though a biopsy is the gold standard for diagnosis, she will need to re-introduce gluten into her diet prior to undergoing the biopsy.

Normal distribution describes the spread of many biological and clinical measurements. Usually, 68.3% lies within 1 standard deviation (SD) of the mean, 95.4% lies within 2 SD of the mean and 99.7% lies within 3 SD of the mean.

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.

If the INR in the range of 2-3 has still resulted in thrombosis, the target INR is increased to 3-4. However, because the risk of bleeding increases as the INR rises, the INR is closely monitored and adjustments are made as needed to maintain the INR within the target range.

In adults, the most common symptom of meningitis is a severe headache, occurring in almost 90% of cases of bacterial meningitis, followed by nuchal rigidity (the inability to flex the neck forward passively due to increased neck muscle tone and stiffness). Other signs commonly associated with meningitis include photophobia (intolerance to bright light) and phonophobia (intolerance to loud noises).
In the United Kingdom empirical treatment consists of a third-generation cefalosporin such as cefotaxime or ceftriaxone. In the USA, where resistance to cefalosporins is increasingly found in streptococci, addition of vancomycin to the initial treatment is recommended. Penicillins, cephalosporins, carbapenems and monobactams all act via inhibition of cell wall synthesis.

Risk factors specific to depression:
-Family history of mental disorder.
-History of previous suicide attempts (this includes self-harm).
-Severe depression.
-Anxiety.
-Feelings of hopelessness.
-Personality disorder.
-Alcohol abuse and/or drug abuse.
-Male gender.

Protective Factors for Suicide.
Protective factors buffer individuals from suicidal thoughts and behaviour. To date, protective factors have not been studied as extensively or rigorously as risk factors. Identifying and understanding protective factors are, however, equally as important as researching risk factors.

Protective Factors:
-Effective clinical care for mental, physical, and substance abuse disorders
-Easy access to a variety of clinical interventions and support for help seeking
-Family and community support (connectedness)
-Support from ongoing medical and mental health care relationships
-Skills in problem solving, conflict resolution, and nonviolent ways of handling disputes
-Cultural and religious beliefs that discourage suicide and support instincts for self-preservation

Memantine is an antagonist of the NMDA (N-Methyl-D-Aspartate)-receptor subtype of glutamate receptor. It is used to slow the neurotoxicity thought to be involved in Alzheimer’s disease and other neurodegenerative diseases.

Drug interactions:
When given concomitantly with other NMDA-receptor antagonists (e.g., ketamine, amantadine) increase the risk of psychosis.
Dopamine agonists, L-dopa, and anticholinergics enhance effects of memantine.
Antispasmodics (e.g., baclofen)  enhance effects, as memantine has some antispasmodic effects.
Drugs excreted by cationic transporters in the kidney (e.g. quinine, cimetidine, ranitidine) reduce excretion.

Common adverse effects include dizziness, headache, confusion, diarrhoea, and constipation.

The patient most likely has reactive arthritis which is usually diagnosed on history and clinical examination. The classic triad of symptoms include conjunctivitis, urethritis and arthritis. Arthritis and conjunctivitis may occur 4-6 weeks after a gastrointestinal or genitourinary infection. Arthritis usually occurs acutely, mostly involving the lower limb and is asymmetrical. Blood culture, urine culture and arthrocentesis (joint aspiration) will not yield positive results.