Refeeding syndrome can be defined as the potentially fatal shifts in fluids and electrolytes that may occur in malnourished patients receiving artificial refeeding (whether enterally or parenterally). These shifts result from hormonal and metabolic changes and may cause serious clinical complications. The hallmark biochemical feature of refeeding syndrome is hypophosphatemia. However, the syndrome is complex and may also feature abnormal sodium and fluid balance; changes in glucose, protein, and fat metabolism; thiamine deficiency; hypokalaemia; and hypomagnesaemia.

Lithium acts by:
– I inhibiting postsynaptic D2 receptor super sensitivity
– Altering cation transport in nerve and muscle cells and influencing reuptake of serotonin or norepinephrine
– Inhibiting phosphatidylinositol cycle second messenger systems

The NICE guidelines for depression and bipolar disorder both recommend Lithium as an effective treatment; patients who take lithium should have regular blood tests to monitor the amount of lithium in their blood (every 3 months), and to make sure the lithium has not caused any problems with their kidneys or thyroid (every 6 months).

Lithium adverse effects include:
– Leucocytosis (most patients) which is when the white cells are above the normal range in the blood.
– Polyuria/polydipsia (30-50%)
– Dry mouth (20-50%)
– Hand tremor (45% initially, 10% after 1 year of treatment)
– Confusion (40%)
– Decreased memory (40%)
– Headache (40%)
– Muscle weakness (30% initially, 1% after 1 year of treatment)
– Electrocardiographic (ECG) changes (20-30%)
– Nausea, vomiting, diarrhoea (10-30% initially, 1-10% after 1-2 years of treatment)
– Hyperreflexia (15%)
– Muscle twitch (15%)
– Vertigo (15%)

Macular disease can affect central vision at any stage of diabetic retinopathy and may be seen in type 2 diabetic patients. Diabetic retinopathy affects up to 80 percent of those who have had diabetes for 20 years or more. Macular oedema occurs when damaged blood vessels leak fluid and lipids onto the macula, the part of the retina that lets us see detail. The fluid makes the macula swell, which blurs vision.

From the given history and physical examination findings, this patient has Bell’s palsy. There is no evidence to suggest involvement of any other cranial nerves, which might raise suspicion of a cerebello-pontine angle space-occupying lesion. With her history of possible optic neuritis, there is a possibility that the lesion is in fact a manifestation of multiple sclerosis, although this should be differentiated by examination of an upper motor neuron lesion (with sparing of the forehead facial muscles because of bilateral innervation). In light of her diabetes and the limited evidence of benefit from corticosteroid use, the most sensible first management step for her would be meticulous eye care to avoid corneal ulceration, as a result of the difficulty she is having closing her left eye.

Diabetes insipidus (DI) is defined as the passage of large volumes (>3 L/24 hr) of dilute urine (< 300 mOsm/kg). It has the following 2 major forms:
– Central (neurogenic, pituitary, or neurohypophyseal) DI, characterized by decreased secretion of antidiuretic hormone (ADH; also referred to as arginine vasopressin [AVP])
– Nephrogenic DI, characterized by decreased ability to concentrate urine because of resistance to ADH action in the kidney
This patient has the central type from metastases.
In patients with central DI, desmopressin is the drug of choice. It is a synthetic analogue of antidiuretic hormone (ADH). It is available in subcutaneous, IV, intranasal, and oral preparations. Generally, it can be administered 2-3 times per day. Patients may require hospitalization to establish fluid needs. Frequent electrolyte monitoring is recommended during the initial phase of treatment.

The vas deferens is a long tube that connects the epididymis to the ejaculatory ducts. It acts as a canal through which mature sperm may pass through the penis during ejaculation.

Most men with CF (97-98 percent) are infertile because of a blockage or absence of the vas deferens, known as congenital bilateral absence of the vas deferens (CBAVD). The sperm never makes it into the semen, making it impossible for them to reach and fertilize an egg through intercourse. The absence of sperm in the semen can also contribute to men with CF having thinner ejaculate and lower semen volume.

Becks triad (hypotension, elevated systemic venous pressure, often with jugular venous distention and muffled heart sounds) is a characteristic collection of clinical findings found in cardiac tamponade. Pulsus paradoxus is also associated with it. The history and clinical findings in this scenario are compatible with the diagnosis of cardica tamponade. The normal respiratory examination excludes tension pneumothorax.

This presentation could be due to either a meningitis or encephalitis, which are clinically not distinguishable from the given history. Encephalitis is mostly viral and in UK herpes simplex virus is the main cause. Advanced neuro imaging and EEG will help to differentiate them however from the given answers CSF analysis is the most appropriate, provided that intracranial pressure is not raised. CSF analysis will help to differentiate a pyogenic meningitis from other forms of meningitis and encephalitis.

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.

Thrombotic thrombocytopenic purpura (TTP) is characterised by the von Willebrand factor (vWF) microthrombi within the vessels of multiple organs. In this condition, the ADAMTS13 metalloprotease enzyme which is responsible for the breakdown of vWF multimer, is deficient, causing its build-up and leading to platelet clots that then decreases the circulating platelets, leading to bleeding in the patient.

Poor prognostic factors for breast cancer include:
1. Young age (<40 years)
2. Premenopausal at the time of diagnosis
3. Increased tumour size
4. High-grade tumour
5. Oestrogen and progesterone receptor-negative tumour
6. Positive lymph node status

A retrospective cohort study of the primary care records of 247 lung cancer patients diagnosed between 1998–2002 showed that 10% of the X-rays were reported as normal.
Other tests may include:
– Imaging tests: A CT scan can reveal small lesions in your lungs that might not be detected on an X-ray.
– Sputum cytology: sputum may reveal the presence of lung cancer cells.
– Tissue sample (biopsy): A sample of abnormal cells may be removed for histological analysis. A biopsy may be performed in a number of ways, including bronchoscopy, mediastinoscopy and needle biopsy. A biopsy sample may also be taken from adjacent lymph nodes.

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.

Acute angle closure glaucoma is associated with hypermetropia, whereas primary open-angle glaucoma is associated with myopia. Glaucoma is a group of eye disorders characterised by optic neuropathy due, in the majority of patients, to raised intraocular pressure (IOP). It is now recognised that a minority of patients with raised IOP do not have glaucoma and vice versa.

Congenital cytomegalovirus infection causes; jaundice, hepatosplenomegaly, petechia, microcephaly, hearing loss and seizures.

Peroneal nerve injury is also known as foot drop. The common peroneal nerve supplies the ankle and toe extensor muscle groups as well as sensation over the dorsum of the foot; thus, there is also loss of sensation in these cases.

The given history suggests a small fibre painful peripheral sensory neuropathy, the most common cause of which is diabetes. Joint position sense and vibratory sensation are carried through large fibres, and therefore are not currently affected. Sensory nerves are affected more often than motor, so reflexes usually remain in tact.

Vitamin B12 deficiency causes impairment of joint position and vibratory sensation.

Chronic inflammatory demyelinating polyneuropathy (CIPD) causes a large fibre peripheral neuropathy with areflexia.

In syringomyelia there is impaired pain and temperature noted in the upper limbs.

Finally, with alcoholic polyneuropathy, all fibre types are affected (sensory and motor loss). It is usually gradual with long term alcohol abuse and may be accompanied by a nutritional deficiency. In addition, pain is a more dominant feature.

It is proven that spironolactone has survival benefits and loop diuretics only give symptomatic relief. Beta blockers are however, known to improve exercise tolerance, left ventricular function and reduce symptoms. They also reduce the mortality associated with heart failure. So administration of beta blockers will reduce the time spent in hospital by improving symptoms.

T. gondii infection in immunocompetent people is usually asymptomatic. It can present as fits in patients with AIDs, who are immunosuppressed. Additionally, infection in the first trimester of pregnancy is very harmful. Congenital toxoplasmosis presents with intracranial calcifications, classically. It can also present with hydrocephalus, microcephaly, blindness, petechiae. Siramycin is the drug of choice to try to prevent vertical transmission from mother to baby. It is typically gotten from cat faeces or raw/undercooked meat, not raw eggs (raw eggs: think salmonella).

The statement that fits the characteristics of doxapram is, epilepsy is a contraindication for doxapram use. Concurrent use with theophylline may increase agitation not relaxation.

Doxapram is a central respiratory stimulant. In clinical practice, doxapram is usually used for patients who have an acute exacerbation of chronic obstructive pulmonary disease (COPD) who are unsuitable for admission to the intensive therapy unit for ventilatory support. Doxapram infusion may buy an extra 24 h to allow for recovery.

Contraindications include: ischaemic heart disease, epilepsy, cerebral oedema, acute stroke, asthma, hypertension, hyperthyroidism, and pheochromocytoma.
The infusion may worsen agitation and dyspnoea and lead to hypertension, nausea, vomiting and urinary retention.

Drug interactions:
Concomitant administration of doxapram and aminophylline (theophylline) can cause increased skeletal muscle activity, agitation, and hyperactivity.

Treatment with ARB or ACE-I may slow further deterioration in renal function in this patient, as studies have shown that blocking of the RAS in type 2 diabetic patients improve renal function.

Glucagon-like peptide 1 (GLP-1) is a 30-amino acid peptide hormone produced in the intestinal epithelial endocrine L-cells by differential processing of proglucagon. GLP-1 is released in response to meal intake.
The main actions of GLP-1 are to stimulate insulin secretion (i.e., to act as an incretin hormone) and to inhibit glucagon secretion, thereby contributing to limit postprandial glucose excursions. It also inhibits gastrointestinal motility and secretion and thus acts as an enterogastrone and part of the ileal brake mechanism. GLP-1 also appears to be a physiological regulator of appetite and food intake.
Decreased secretion of GLP-1 may contribute to the development of obesity, and exaggerated secretion may be responsible for postprandial reactive hypoglycaemia.

Age-related macular degeneration is the most common cause of blindness in the UK. Degeneration of the central retina (macula) is the key feature with changes usually bilateral. Smoking and genetic factors are risk factors for macular degeneration. The severity is divided into early, intermediate, and late types. The late type is additionally divided into dry and wet forms with the dry form making up 90% of cases.

Good prognosis of chronic lymphocytic leukaemia (CLL) is associated with deletion of the long arm of chromosome 13 (del 13q). This is the most common abnormality, seen in around 50% of all CLL patients. Poor prognosis of the disease is related to deletion of part of the short arm of chromosome 17 (del 17p). This is seen in around 5-10% of the patients suffering from CLL.

Poor prognostic factors of CLL include:
1. Male sex
2. Age >70 years
3. Lymphocyte count >50
4. Prolymphocytes comprising more than 10% of blood lymphocytes
5. Lymphocyte doubling time <12 months
6. Raised LDH
7. CD38 expression positive

The patient is asymptomatic but matches the diagnostic criteria for multiple myeloma (MM). Therefore, the underlying diagnosis of this condition is smouldering multiple myeloma (SMM). SMM is an early precursor to MM. Its treatment is typically to watch and wait.

MM is a neoplasm of the bone marrow plasma cells. Peak incidence is in patients aged 60–70 years.

Clinical features of MM include:
1. Ostealgia, osteoporosis, pathological fractures (typically vertebral), and osteolytic lesions
2. Lethargy
3. Infections
4. Hypercalcaemia
5. Renal failure
6. Other features: amyloidosis e.g. macroglossia, carpal tunnel syndrome; neuropathy; hyperviscosity

Diagnosis of MM is based on the confirmation of (a) one major criterion and one minor criterion or (b) three minor criteria in an individual who has signs or symptoms of multiple myeloma.

Major criteria:
1. >30% plasma cells on bone marrow biopsy
2. Monoclonal band of paraprotein on electrophoresis: >35g/L for IgG, 20g/L for IgA, or >1g of light chains excreted in the urine per day

Minor criteria:
1. 10–30% plasma cells on bone marrow biopsy
2. Abnormal monoclonal band but levels less than listed above
3. Lytic bone lesions observed radiographically
4. Immunosuppression

Before the initiation of trastuzumab, an echocardiography is a must to rule out any pre-existing cardiac abnormalities as trastuzumab is cardiotoxic.

Trastuzumab (Herceptin) is a monoclonal antibody directed against the HER2/neu receptor. It is used mainly in metastatic breast cancer although some patients with early disease are now also given trastuzumab.

Adverse effects include:
Flu-like symptoms and diarrhoea are common.
Cardiotoxicity:
– Risk increases when anthracyclines are used concomitantly.
– Trastuzumab-induced cardiac dysfunctions are regarded as less severe and largely reversible because primary cardiomyocyte do not show ultrastructure changes unlike those associated with anthracycline-induced cardiotoxicity.
– Primary myocyte injury does not occur in patients who were treated with trastuzumab.

A lucid interval, in which the patient portrays a temporary improvement in condition after a traumatic brain injury, is especially indicative of an epidural haematoma.

Pulmonary metastasis is seen in 20-54% of extrathoracic malignancies. The lungs are the second most frequent site of metastases from extrathoracic malignancies. Twenty percent of metastatic disease is isolated to the lungs. The development of pulmonary metastases in patients with known malignancies indicates disseminated disease and places the patient in stage IV in TNM (tumour, node, metastasis) staging systems.
Chest radiography (CXR) is the initial imaging modality used in the detection of suspected pulmonary metastasis in patients with known malignancies. Chest CT scanning without contrast is more sensitive than CXR.
Breast, colorectal, lung, kidney, head and neck, and uterus cancers are the most common primary tumours with lung metastasis at autopsy. Choriocarcinoma, osteosarcoma, testicular tumours, malignant melanoma, Ewing sarcoma, and thyroid cancer frequently metastasize to lung, but the frequency of these tumours is low.

Sevelamer is a phosphate-binding drug that can lower raised serum phosphate levels in chronic kidney disease. Because of its aluminium-related side-effects, aluminium hydroxide is no longer the drug of choice.
The other options are calcium-containing salts that may increase risks of tissue calcification.

Right ventricular volume overload is indicated by a parasternal heave and right axis deviation. Oxygen saturation in right atrium is higher than oxygen saturation of the inferior and superior vena cavae. So the most probable diagnosis is atrial septal defect.