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%)

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.

The most likely diagnosis is chronic tophaceous gout, which is classically associated with chronic renal impairment or long term diuretic therapy. There is tophus formation due to urate crystal deposition in and around the joint. These tophi can also form in the bones and soft tissues. Renal manifestations with uric acid include nephrolithiasis and uric acid nephropathy. Whenever there is an acute on chronic attack of gout, the inciting cause must be established and in case of diuretic use, they should be immediately replaced with another medication. Allopurinol is never started during an acute episode. it is first allowed to settle before administration of allopurinol. Although dietary restriction must be observed in people with a propensity of gout, this scenario clearly presents diuretics as the cause.

Ostium secundum atrial septal defects are known to cause stroke due to the passage of emboli from the right sided circulation to the left sided circulation. ECG shows tall, peaked P waves (usually best seen in leads II and V2) and prolongation of the PR interval, rSR pattern in leads V3 R and V1 as well as right axis deviation.

The blood investigations in this patient reveal hyponatremia as well as hypokalaemia. Among the options provided, Bendroflumethiazide therapy can cause the above presentation with the electrolyte disturbances.
Note:
– Spironolactone is a potassium-sparing diuretic that is associated with hyperkalaemia.
– Enalapril therapy can cause side effects of dizziness, hypotension, cough, and rarely a rash.
– Felodipine therapy can cause side effects of dizziness, headache, cough, and palpitations.

CHA₂DS₂-VASc score is used for atrial fibrillation stroke risk calculation.
Congestive heart failure – 1 point
Hypertension – 1 point
Age ≥75 years – 2 points
Diabetes mellitus – 1 point
Stroke/Transient Ischemic Attack/Thromboembolic event – 2 points
Vascular disease (prior MI, PAD, or aortic plaque) – 1 point
Age 65 to 74 years – 1 point
Sex category (i.e., female sex) – 1 point
Score of 2 or more is considered as high risk and anticoagulation is indicated. This patient’s score is 4, so he needs life-long warfarin to prevent a stroke.

The wedged hepatic venous pressure is a reflection of the portal venous pressure in the hepatic sinusoids. This is a fact to remember. Here is a great but concise explanation as to why: https://www.ncbi.nlm.nih.gov/pubmed/18695309

The type of significance test used depends on whether the data is parametric (can be measured, usually normally distributed) or non-parametric.
Parametric tests:
Student’s t-test – paired or unpaired*
Pearson’s product-moment coefficient – correlation

Non-parametric tests:
Mann-Whitney U test – unpaired data
Wilcoxon signed-rank test – compares two sets of observations on a single sample
chi-squared test – used to compare proportions or percentages
Spearman, Kendall rank – correlation.

The outcome measured is not normally distributed, i.e. it is non-parametric. This excludes the Student’s t-tests. We are not comparing percentages/proportions so the chi-squared test is excluded. The Mann–Whitney U test is a nonparametric test of the null hypothesis that it is equally likely that a randomly selected value from one sample will be less than or greater than a randomly selected value from a second sample.
This test can be used to investigate whether two independent samples were selected from populations having the same distribution.

Uric acid stones will most likely be found in this case because of the patient’s long history of gout. Additionally, studies have shown that ileostomy patients have an increased risk for the development of uric acid stones.

Interleukin 1 alpha and interleukin 1 beta (IL1 alpha and IL1 beta) are cytokines that participate in the regulation of immune responses, inflammatory reactions, and hematopoiesis. It is secreted mainly by macrophages and monocytes and acts as a costimulator of T cell and B cell proliferation.

The history is suggestive of leptospirosis. This is a zoonotic infection caused by a spirochete. As the patient is in shock, resuscitation with IV fluids is the first step in the management. IV antibiotics should be started (Doxycycline or Penicillin) as soon as possible. Other investigations mentioned are important during the management to rule out other possible diagnoses.

Alveolar haemorrhage (AH) is a rare, but serious manifestation of SLE. It may occur early or late in disease evolution. Extrapulmonary disease may be minimal and may be masked in patients who are already receiving immunosuppressants for other symptoms of SLE.

DLCO or TLCO (diffusing capacity or transfer factor of the lung for carbon monoxide (CO)) is the extent to which oxygen passes from the air sacs of the lungs into the blood.
Factors that can increase the DLCO include polycythaemia, asthma (can also have normal DLCO) and increased pulmonary blood volume as occurs in exercise. Other factors are left to right intracardiac shunting, mild left heart failure (increased blood volume) and alveolar haemorrhage (increased blood available for which CO does not have to cross a barrier to enter).

Hyperthermia (Temperature 39.5 C) points towards the use of ecstasy.

MDMA (3,4 – methylenedioxymethamphetamine), or more commonly known as Molly or Ecstasy, is a synthetic psychoactive substance.
Patients who consumed MDMA may present in a tachycardic, hypertensive, hyperthermic, and agitated state.
Adverse effects, even at minor recreational doses, include increased muscle activity (such as bruxism, restless legs, and jaw clenching), hyperactivity, insomnia, difficulty concentrating and feelings of restlessness.

Treatment of MDMA overdose:
Emphasis should be on maintaining the airway along with the stabilization of breathing and circulation.
Patients may present obtunded due to hyponatremia requiring endotracheal intubation.
For the hyperthermic patient, evaporative cooling along with ice packs to the groin and axilla are beneficial.
Patients who present in severe toxicity within one hour of ingestion can receive activated charcoal PO or via an NG tube.
Antipyretics, such as acetaminophen, should be avoided as they have no role and can worsen an already compromised liver.

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

The immunological changes in HIV include depletion in CD4+ T cell, cytokine dysregulation and immune dysfunction. The dominant immunologic feature of HIV infection is progressive depletion of the helper T cell (CD4+ T cell), which reverses the normal CD4:CD8 ratio and subsequently lead to immunodeficiency. Other imuunological changes include:
increased B2-microglobulin
decreased IL-2 production
polyclonal B-cell activation
decreased NK cell function
reduced delayed hypersensitivity responses

This case describes Zollinger-Ellison syndrome. It is characterized by refractory peptic ulcer disease, often multiple ulcers. This is typically caused by secretion of gastrin from a gastrinoma, a neuroendocrine tumour. The most common site of ulceration is the duodenum. A symptom of a pancreatic gastrinoma may be steatorrhea from hypersecretion of gastrin. Serum gastrin levels > 1000 and a pH < 2 are diagnostic of pancreatic gastrinoma. The secretin test is a test that can differentiate gastrinoma from other causes of high gastrin levels. Gastrin will rise after secretin injection if the patient has a gastrinoma.

The patient has acute promyelocytic leukaemia (APML) with associated disseminated intravascular coagulation (DIC). Although
the platelet count is high, platelet function is ineffective.

Patients may present, as in this case, with severe bleeding, and the most appropriate emergency treatment would be administration of fresh frozen plasma (FFP).

Finasteride is often prescribed for patients with Benign Prostatic Hyperplasia (BPH) or enlarged prostate. However, it has been known to cause a decrease in Prostatic Specific Antigen (PSA) levels in patients with BPH, which may lead to false negatives in a case like this, where a palpable mass has been detected and malignancy is suspected.

Blue tinge of vision/cyanopsia is caused due to the intake of sildenafil citrate.

Sildenafil citrate (Viagra) is the first oral drug to be widely approved for the treatment of erectile dysfunction.
It is a potent and selective inhibitor of type-V phosphodiesterase, the primary form of the enzyme found in human penile erectile tissue, thereby preventing the breakdown of cyclic guanosine monophosphate (cGMP), the intracellular second messenger of nitric oxide.

Uses:
It is used for the treatment of erectile dysfunction, idiopathic pulmonary hypertension, premature ejaculation, high altitude illness, penile rehabilitation after radical prostatectomy, angina pectoris, and lower urinary tract symptoms.

Adverse effects:
Mild headache, flushing, dyspepsia, cyanopsia, back pain, and myalgias – due to a high concentration of PDE11 enzyme in skeletal muscle, which shows significant cross-reactivity with the use of tadalafil.
It can also cause hypotension, dizziness, and rhinitis.

Note: Xanthopsia (yellow-green vision) may occur secondary to treatment with digoxin.

The cause for bone marrow suppression in this patient is most probably mercaptopurine toxicity.
Azathioprine is metabolized to 6-mercaptopurine (6-MP), which itself is metabolized by xanthine oxidase.
Xanthine oxidase inhibition by allopurinol leads to the accumulation of 6-MP which then precipitates bone marrow failure.
This may be potentially fatal if unrecognized.
Clinical presentation:
Toxicity symptoms include gastrointestinal symptoms, bradycardia, hepatotoxicity, myelosuppression.

One of the options of Psoriasis treatment is vitamin D analogues i.e. calcipotriol. Acne is exacerbated by steroids. Erythema nodosum can be caused by various diseases and the treatment of the primary condition resolves the symptoms. Lipomas require surgery, whereas Steven-Johnson syndrome requires use of steroids and eliminating the culprit drug, which is one of the most common causes.

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

Squamous-cell skin cancer usually presents as a hard lump with a scaly top but can also form an ulcer. Onset is often over months and it is more likely to spread to distant areas than basal cell cancer vie the lymphatics. The greatest risk factor is high total exposure to ultraviolet radiation from the Sun. Other risks include prior scars, chronic wounds, actinic keratosis, lighter skin, Bowen’s disease, arsenic exposure, radiation therapy, poor immune system function, previous basal cell carcinoma, and HPV infection. While prognosis is usually good, if distant spread occurs five-year survival is ,34%

Warfarin inhibits the vitamin K-dependent procoagulants II, VII, IX, and X as well as anticoagulant protein C and S. It is highly protein-bound and can be displaced by a wide variety of drugs. It has a half-life of 36–48 hours.

Bleeding is the major side effect. Easy bruising, as seen in this case, is commonly seen in patients of warfarin overdose. Grossly prolonged PT and lesser increase in APTT may be seen in such cases.

The rash is a characteristic sign of meningitis. Added to photophobia, headache and neck rigidity, meningitis is highly suggested diagnosis. IV antibiotics should be started immediately.

Acute, symptomatic hypocalcaemia is treated with 10ml of 10% calcium gluconate over 10 minutes.

Charles Bonnet syndrome (CBS) involves visual hallucinations due to eye disease, usually associated with a sharp decline in vision. The phenomenon is seen in patients with moderate or severe visual impairment. It can occur spontaneously as the vision declines or it may be precipitated, in predisposed individuals, by concurrent illness such as infections elsewhere in the body.

It is not clear why CBS develops or why some individuals appear to be predisposed to it. It is particularly noted in patients with advanced macular degeneration. It has been suggested that reduced or absent stimulation of the visual system leads to increased excitability of the visual cortex (deafferentation hypothesis). This release phenomenon is compared to phantom limb symptoms after amputation.

CBS is much more common in older patients because conditions causing marked visual loss are more common in older people. However, it can occur at any age and has been described in children.
The prevalence is hard to assess due to considerable under-reporting, perhaps because patients frequently fear that it is a sign of mental illness or dementia. However, it is thought to occur in:
About 10-15% of patients with moderate visual loss.
Possibly up to 50% of people with severe visual loss.
Presentation:
The nature of the hallucination depends on the part of the brain that is activated. The hallucinations may be black and white or in colour. They may involve grids/brickwork/lattice patterns but are typically much more complex:

The hallucinations are always outside the body.
The hallucinations are purely visual – other senses are not involved.
The hallucinations have no personal meaning to the patient.
Hallucinations may last seconds, minutes or hours.
CBS tends to occur in a ‘state of quiet restfulness’. This may be after a meal or when listening to the radio (but not when dozing off).
Symptoms also have a tendency to occur in dim lighting conditions.
Patients may report high levels of distress, with some patients reporting anger, anxiety and even fear associated with the hallucinations.

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)

An overall concordance rate in monozygotic twins was documented to be 25% as compared to dizygotic twins with 3%. First degree relatives have a chance of around 3% of developing the disease. Caucasians show an increase frequency of HLA-B8. The Japanese lupus patients had a stronger association with HLA-DR2.

Triamterene is a potassium-sparing diuretic that can cause hyperkalaemia, therefore, it was stopped in this patient. With all other lab results returning normal values and a normal ECG, management will simply require repeating the U & E after one week since the Triamterene has already be stopped.