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 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.

Atopic dermatitis is an allergic condition which is more apparent in those children who have a positive family history in their 1st or 2nd degree relatives. In some cases, there might be a positive history of bronchial asthma. The best treatment option in this case would be topical application of 1% hydrocortisone ointment to the affected areas of the child. We cannot prescribe a strong ointment to the face because it may lead to skin atrophy, telangiectasia and other steroid related topical complications.

This is most likely describing irritable bowel syndrome (IBS). Symptoms are either diarrhoea, constipation, or both, abdominal pain, bloating, of varying duration. It is a functional, not an 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.

This is a classic clinical presentation, with alcohol intake and nausea/vomiting that leads to hematemesis, of a Mallory-Weiss tear. In Mallory-Weiss tear, they typically present as a hemodynamically stable patient after a night of binge drinking and excessive resultant vomiting. Given his EGD did not show any other pathology and he is now stable, he can be discharged home.

Graves’ disease is the most common cause of thyrotoxicosis in pregnancy.

– Poor control of thyrotoxicosis is associated with pregnancy loss, pregnancy-induced hypertension, prematurity, low birth weight, intrauterine growth restriction, stillbirth, thyroid storm, and maternal congestive heart failure.

– Antithyroid drugs are the treatment of choice of hyperthyroidism during pregnancy. The lowest dose of ATD needed to maintain TT4 1.5× the upper limit of the non-pregnant reference range or FT4 at the upper limit of the reference range should be used.
Two different antithyroid drug (ATD) regimens are in common use for Grave’s disease: i) Titration method and ii) Block-and-replace method.
In the titration method, the usual starting dose is 15–30 mg/day methimazole (or equivalent doses of other thionamides); further to periodic thyroid status assessment, daily dose is tapered down to the lowest effective dose (avoiding both hyper- and hypothyroidism).
The block-and-replace method uses persistently high ATD doses in association with L-thyroxine replacement to avoid hypothyroidism; treatment lasts 6 months. This method has advantages and disadvantages over the titration method. Higher doses of ATDs may have a greater immunosuppressive action useful for a permanent remission of hyperthyroidism, but this effect remains to be demonstrated.
Avoidance of hypothyroidism or ‘escape’ of hyperthyroidism seems easier than with the titration method; treatment is shorter, and the number of visits lower. On the other hand, the much higher number of tablets taken every day may create problems of poor compliance. The block-and-replace method should not be used during pregnancy.

– Breastfeeding has been shown to be safe in mothers taking ATDs in appropriate doses.

PCR is a simple, yet elegant, enzymatic assay, which allows for the amplification of a specific DNA fragment from a complex pool of DNA. PCR can be performed using source DNA from a variety of tissues and organisms, including peripheral blood, skin, hair, saliva, and microbes. Only trace amounts of DNA are needed for PCR to generate enough copies to be analysed using conventional laboratory methods. For this reason, PCR is a sensitive assay. Each PCR assay requires the presence of template DNA, primers, nucleotides, and DNA polymerase. The DNA polymerase is the key enzyme that links individual nucleotides together to form the PCR product. The above mentioned components are mixed in a test tube or 96-well plate and then placed in a machine that allows repeated cycles of DNA amplification to occur in three basic steps. The machine is essentially a thermal cycler. It has a thermal block with holes, into which the test tubes or plates holding the PCR reaction mixture are inserted. The machine raises and lowers the temperature of the block in discrete, precise and pre-programmed steps. The reaction solution is first heated above the melting point of the two complementary DNA strands of the target DNA, which allows the strands to separate, a process called denaturation. The temperature is then lowered to allow the specific primers to bind to the target DNA segments, a process known as hybridization or annealing. Annealing between primers and the target DNA occurs only if they are complementary in sequence (e.g. A binding to G). The temperature is raised again, at which time the DNA polymerase is able to extend the primers by adding nucleotides to the developing DNA strand. With each repetition of these three steps, the number of copied DNA molecules doubles.

The major delayed problem with radiotherapy is the development of secondary cancers. This risk begins to appear ten years after therapy.

CURB Pneumonia Severity Score estimates the mortality of community-acquired pneumonia to help determine inpatient vs. outpatient treatment.
Select Criteria:
Confusion (abbreviated Mental Test Score <=8) (1 point)
Urea (BUN > 19 mg/dL or 7 mmol/L) (1 point)
Respiratory Rate > 30 per minute (1 point)
Blood Pressure: diastolic < 60 or systolic < 90 mmHg (1 point) The CURB-65 scores range from 0 to 5. Clinical management decisions can be made based on the score:
Score Risk Disposition
0 or 1 – 1.5% mortality – Outpatient care
2 – 9.2% mortality – Inpatient vs. observation admission
≥ 3 – 22% mortality – Inpatient admission with consideration for ICU admission with score of 4 or 5

Pseudogout is a paroxysmal joint inflammation due to calcium pyrophosphate crystal deposition (calcium pyrophosphate dihydrate). Aetiology includes mostly idiopathic (primary form) and secondary form occurring as a result of joint trauma, familial chondrocalcinosis, hyperparathyroidism, hemochromatosis, gout, hypophosphatemia. Clinical presentation: Often asymptomatic.
Acute (pseudogout attack): monoarthritis (rarely oligoarthritis), mostly affecting the knees and other large joints (e.g., hips, wrists, and ankles). It may become chronic (can affect multiple joints). Osteoarthritis with CPPD (most common form of symptomatic CPPD): progressive joint degeneration with episodes of acute inflammatory arthritis typical of pseudogout attacks. Arthrocentesis should be performed, especially in acute cases. Polarized light microscopy: detection of rhomboid-shaped, positively birefringent CPPD crystals. Synovial fluid findings: 10,000-50,000 WBCs/μL with > 90% neutrophils. X-ray findings: cartilage calcification of the affected joint (chondrocalcinosis). Fibrocartilage (meniscus, annulus fibrosus of intervertebral disc) and hyaline cartilage (joint cartilage) may be affected.

Botulinum toxin is a neurotoxic protein from Clostridium botulinum that causes flaccid paralysis as it acts by preventing the release of Ach at the neuromuscular joint. It is the first-line treatment for cervical dystonia (torticollis) because the condition is a neurological disorder characterised by unusual muscle contractions of the neck. With the use of Botulinum toxin, the contractions would be released.

The water deprivation test (i.e., the Miller-Moses test), is a semiquantitative test to ensure adequate dehydration and maximal stimulation of ADH for diagnosis. It is typically performed in patients with more chronic forms of Diabetes Insipidus (DI). The extent of deprivation is usually limited by the patient’s thirst or by any significant drop in blood pressure or related clinical manifestation of dehydration.

In healthy individuals, water deprivation leads to a urinary osmolality that is 2-4 times greater than plasma osmolality. Additionally, in normal, healthy subjects, administration of ADH produces an increase of less than 9% in urinary osmolality. The time required to achieve maximal urinary concentration ranges from 4-18 hours.

In central and nephrogenic DI, urinary osmolality will be less than 300 mOsm/kg after water deprivation. After the administration of ADH, the osmolality will rise to more than 750 mOsm/kg in central DI but will not rise at all in nephrogenic DI. In primary polydipsia, urinary osmolality will be above 750 mOsm/kg after water deprivation.
A urinary osmolality that is 300-750 mOsm/kg after water deprivation and remains below 750 mOsm/kg after administration of ADH may be seen in partial central DI, partial nephrogenic DI, and primary polydipsia.

Features that affect prognosis are tumour thickness in millimetres (Breslow’s depth – the deeper the Breslow thickness the poorer the prognosis.), depth related to skin structures (Clark level – the level of invasion through the dermis), type of melanoma, presence of ulceration, presence of lymphatic/perineural invasion, presence of tumour-infiltrating lymphocytes (if present, prognosis is better), location of lesion, presence of satellite lesions, and presence of regional or distant metastasis. Malignant melanoma tends to grow radially before entering a vertical growth phase. The diameter it reaches has not been found to be a prognostic factor.

Temazepam is a medication that is often prescribed for the treatment of short-term insomnia. It belongs to the benzodiazepine family of drugs and is classed as intermediate-acting, meaning that it can take between six and twenty-four hours for the drug to take effect.

Although it is known that shorter-acting benzodiazepines are more harmful and more likely to cause addiction, temazepam is, nevertheless, a highly addictive drug. It should not be taken for longer than four weeks.

-Adverse effects associated with the use of benzodiazepine hypnotics (to which the elderly are most vulnerable) include confusion, over sedation, increased risks of falls and consequent fractures

-Withdrawal from a benzodiazepine hypnotic must be agreed between the clinician and the patient – patients should never be forced or threatened. The risks of continued benzodiazepine use should be explained. An agreed schedule for reduction of and gradual withdrawal from the benzodiazepine hypnotic should also be agreed. This will involve substitution of the hypnotic with a long-acting benzodiazepine (e.g. diazepam) and a subsequent gradual reduction in dose of the substituted benzodiazepine -the substituted benzodiazepine can then be withdrawn in steps of about one-eighth to one-tenth every fortnight
Example: withdrawal schedule for patient on temazepam 20mg nocte
week 1 – temazepam 10mg, diazepam 5mg
week 2 – stop temazepam, diazepam 10mg
week 4 – diazepam 9mg
week 6 – diazepam 8mg
continue reducing dose of diazepam by 1mg every fortnight – tapering of dose may be slower if necessary

Diagnosis of multiple myeloma (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

Pulsus alternans is the alternation of one strong and one weak beat without a change in the cycle length. It occurs most commonly in heart failure due to increased resistance to LV ejection, as occurs in hypertension, aortic stenosis, coronary atherosclerosis, and dilated cardiomyopathy. Pulsus alternans is usually associated with an S3 gallop, which is associated with a poor prognosis. It usually disappears with treatment of the heart failure.

Normal distribution, also known as the Gaussian distribution, is a probability distribution that is symmetric about the mean. The normal distribution has the following properties:
– It is symmetric around the mode, the median and the mean of the distribution.
– It is unimodal
– The area under the curve and over the x-axis is unity (i.e. equal to one).
– Its density has two inflection points.
– Its density is log-concave.
The standard deviation (SD) is a measure of how much dispersion exists from the mean. SD = square root (variance)

A prominent A wave is observed in the jugular venous pulse and this indicates the presence of established pulmonary hypertension. In addition the pulmonic component of the second heart sound (P2) may be increased and the P2 may demonstrate fixed or paradoxical splitting. The signs of right ventricular failure include a high-pitched systolic murmur of tricuspid regurgitation, hepatomegaly, a pulsatile liver, ascites, and peripheral oedema.

J waves in an ECG is associated with hypothermia, hypercalcemia, the Brugada syndrome, and idiopathic ventricular fibrillation. The other responses are all associated with atrial myxoma

The positive family history and the smoking make him an ideal candidate for a myocardial infarction. The chest pain is also a suggestive symptom. So troponin is needed to rule out MI.