Melanocytic nevi are benign neoplasms or hamartomas composed of melanocytes. Melanocytes are derived from the neural crest and migrate during embryogenesis to selected ectodermal sites (primarily the skin and the CNS), but also to the eyes and the ears.
They tend to appear during early childhood and during the first 30 years of life. They may change slowly, becoming raised, changing color or gradually fading.. Pregnancy can increase the number of naevi as well as the degree of hyperpigmentation.
They may become malignant and this should be suspected if the naevus increases in size, develops an irregular surface or becomes darker, itches or bleeds.

Extended-spectrum beta-lactamases (ESBL) are enzymes that confer resistance to most beta-lactam antibiotics, including penicillins, cephalosporins, and the monobactam aztreonam. Extended spectrum beta-lactamase (ESBL) production is the main reason for multi-drug resistance among E.coli. Commonly used medications to treat ESBL-involved infections include carbapenems (imipenem, meropenem, and doripenem), cephamycins (cefoxitin and cefotetan), Fosfomycin, nitrofurantoin, beta-lactamase inhibitors (clavulanic acid, tazobactam, or sulbactam), non-beta-lactamases and colistin (if all other medications have failed.)

Illness anxiety disorder (IAD) is a recent term for what used to be diagnosed as hypochondriasis, or hypochondrial disorder. People diagnosed with IAD strongly believe they have a serious or life-threatening illness despite having no, or only mild, symptoms.

Symptoms of IAD may include:
-Excessive worry over having or getting a serious illness.
-Physical symptoms are not present or if present, only mild. If another illness is present, or there is a high risk for developing an illness, the person’s concern is out of proportion.
-High level of anxiety and alarm over personal health status.
-Excessive health-related behaviours (e.g., repeatedly checking body for signs of illness) or shows abnormal avoidance (e.g., avoiding doctors’ appointments and hospitals).
-Fear of illness is present for at least six months (but the specific disease that is feared may change over that time).
-Fear of illness is not due to another mental disorder.

The patient is most likely to have Postpartum thyroiditis which goes through 2 phases; hypothyroid and a hyperthyroid phase.
The hyperthyroid phase of postpartum thyroiditis occurs between 2 and 10 months postpartum. Most commonly, it presents at 3 months. Symptoms more common in women with hyperthyroid postpartum thyroiditis include palpitations, fatigue, heat intolerance, and irritability/nervousness. The frequency of asymptomatic hyperthyroidism is 33%.
Untreated, the hyperthyroidism resolves spontaneously within 2–3 months. This phase is diagnosed by the combination of a low serum TSH concentration in the presence of thyroid peroxidase antibodies, in women who are TSH receptor antibody-negative. Free T4 levels are typically elevated but may be normal.
Treatment of hyperthyroidism, when necessary, is based on symptom severity and should be a joint decision of patient and physician. Beta-blockers such as propranolol are given to alleviate palpitations, irritability, and nervousness. The morbidity associated with treatment is the side effects of beta-blockade. The downside of withholding treatment is allowing the woman to remain symptomatic. Antithyroid medicines (thioureas) are not a potential treatment alternative, because the hyperthyroidism is caused by destructive thyroiditis resulting in the release of preformed thyroid hormone.

Generalized Anxiety Disorder (GAD) is characterized by persistent and excessive worry about a number of different things. People with GAD may anticipate disaster and may be overly concerned about money, health, family, work, or other issues. Individuals with GAD find it difficult to control their worry. They may worry more than seems warranted about actual events or may expect the worst even when there is no apparent reason for concern.

GAD is diagnosed when a person finds it difficult to control worry on more days than not for at least six months and has three or more symptoms.

Treatment usually consists of a combination of pharmacotherapy and/or psychotherapy. Antidepressant agents are the drugs of choice in the treatment of anxiety disorders, particularly the newer agents, which have a safer adverse effect profile and higher ease of use than the older tricyclic antidepressants (TCAs), such as selective serotonin reuptake inhibitors (SSRIs).

A typical attack may last less than an hour but can also persist for longer. In primary Raynaud’s, attacks are more likely symmetric, episodic, and without evidence of peripheral vascular disease. Patients more commonly have a negative ANA and normal inflammatory markers. There should be no evidence of tissue gangrene, digital pitting, or tissue injury in primary Raynaud’s. In contrast, patients with secondary Raynaud’s will describe attacks that are more frequent, painful, often asymmetric and may lead to digital ulcerations.

In the petrous temporal bone the facial nerve produces three branches:
1. The greater petrosal nerve, which transmits preganglionic parasympathetic fibres to the sphenopalatine ganglion. These postganglionic fibres supply the lacrimal gland and the glands in the nasal cavity;
2. The nerve to stapedius;
3. Parasympathetic fibres to the submandibular and sublingual glands and taste fibres from the anterior two-thirds of the tongue.

Given she is not showing signs of systemic illness, you do not need to treat for an acute flair (which would be steroids), but you need to put her on maintenance medication. Oral ASA would be the best option for this, it is first line. You cannot give rectal ASA because the location of her disease is in the ascending colon and the enema will not reach.

The cytochrome p450 3A4 enzyme system in the liver is affected by grapefruit juice.

Patients taking antihistamines should be advised to avoid drinking grapefruit juice. This is because constituents of grapefruit juice such as naringin and bergamottin inhibit CYP3A4 in the liver, particularly at high doses, leading to decreased drug elimination via hepatic metabolism and can increase potential drug toxicities.

Inhibition of this enzyme system leads to reduced metabolism of antihistamines leading to an increased incidence of side effects like excessive drowsiness and nausea as in this patient.

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.

The correct answer is patchy inflammation. Superficial ulceration as well as non-patchy inflammation are seen in ulcerative colitis (UC) in the colon and rectum; you would expect to see transmural inflammation in Crohn’s disease and it can be patchy and located anywhere from mouth to anus. Crypt distortion and crypt abscesses are seen in both UC and Crohn’s, however they are more common in ulcerative colitis.

Again, remember the Hepatitis B serologies: In chronic hepatitis B infection, you have +HBsAg, +anti-HBc, (-)IgM antiHBc, and (-) anti-HBs. In acute hepatitis B infection, you have +HBsAg, + anti-HBc, + IgM anti-HBc, and negative anti-HBs. In immunity due to natural infection, you have negative HBsAg, + anti-HBc, and + anti-HBs. In immunity due to vaccination, you have negative HBsAg, negative anti-HBc, and positive anti-HBs. IN THIS CASE, the person is HBsAg+ for 6 months and everything else is negative, normal transaminase. They do not need antiviral therapy, but their serology should be monitored serially. There would be no reason to do a liver biopsy.

Pneumocystis Jiroveci. This causative organism is responsible for pneumonia in individuals that have a compromised immune system. Symptoms include cyanosis, dry cough and in some cases, diffuse bilateral alveolar shadows on CXR. Co-trimoxazole is normally the treatment for this.

To confirm the diagnosis, especially in patients with negative anti-Ro or anti-La antibodies, labial gland biopsy is done. In performing a labial biopsy, the surgeon typically makes a shallow 1/2 inch wide incision on either side of the inner lip after numbing the area with a local anaesthetic. Schirmer’s test determines whether the eye produces enough tears to keep it moist. This test can be done for ocular symptoms of Sjogren syndrome but is of no diagnostic importance as it can be positive with many other diseases.

The farmer has most likely ingested an organophosphate insecticide.
Organophosphorus compounds are used widely as:
• Insecticides – Malathion, parathion, diazinon, dichlorvos
• Nerve gases – Soman, sarin, tabun, VX
• Ophthalmic agents – Echothiophate
• Antihelmintics – Trichlorfon
• Herbicides – merphos
• Industrial chemical (plasticizer) – Tricresyl phosphate
Signs and symptoms of Organophosphorus Poisoning (OPP) can be classified as:
• Muscarinic effects:
o Cardiovascular – Bradycardia, hypotension
o Respiratory – Rhinorrhoea, bronchorrhea, bronchospasm, cough, severe respiratory distress
o Gastrointestinal – Hypersalivation, nausea and vomiting, abdominal pain, diarrhoea, faecal incontinence
o Genitourinary – Incontinence
o Ocular – Blurred vision, miosis
o Glands – Increased lacrimation, diaphoresis
• Nicotinic effects:
o Muscle fasciculation, weakness, cramping, diaphragmatic failure, and autonomic side effects include: hypertension, tachycardia, and mydriasis.
• Central nervous system (CNS) effects:
o Anxiety, emotional lability, restlessness, confusion, ataxia, tremors, seizures, coma, apnoea
Mainstay Treatment:
• Decontamination
• Securing Airway, Breathing and Circulation
• Atropine
• Pralidoxime
• Benzodiazepines

Astereognosis is associated with lesions to the parietal lobe, not the temporal lobe, so this symptom would not arise in this patient.

Among the given options the most appropriate management in this patient would be ethanol and haemodialysis.

Ethanol competes with ethylene glycol for alcohol dehydrogenase and thus, helps manage a patient with ethylene glycol toxicity.

Ethylene glycol is a type of alcohol used as a coolant or antifreeze
Features of toxicity are divided into 3 stages:
Stage 1: (30 min to 12 hours after exposure) Symptoms similar to alcohol intoxication: confusion, slurred speech, dizziness (CNS depression)
Stage 2: (12 – 48 hours after exposure) Metabolic acidosis with a high anion gap and high osmolar gap. Also tachycardia, hypertension
Stage 3: (24 – 72 hours after exposure) Acute renal failure

Management has changed in recent times:
Fomepizole, an inhibitor of alcohol dehydrogenase, is now used first-line in preference to ethanol.
Ethanol has been used for many years works by competing with ethylene glycol for the enzyme alcohol dehydrogenase this limits the formation of toxic metabolites (e.g. glycolaldehyde and glycolic acid) which are responsible for the hemodynamic/metabolic features of poisoning.
Haemodialysis has a role in refractory cases.

The most probable diagnosis in this patient is serotonin syndrome.

The serotonin syndrome is a cluster of symptoms and signs (range from barely perceptible tremor to life-threatening hyperthermia and shock).
It may occur when SSRIs such as citalopram, escitalopram, fluoxetine, fluoxetine, paroxetine, and sertraline that impair the reuptake of serotonin from the synaptic cleft into the presynaptic neuron are taken in combination with monoamine oxidase inhibitors or tricyclic antidepressants. It has also been reported following an overdose of selective serotonin reuptake inhibitors (SSRIs) alone.

Treatment:
Most cases of serotonin syndrome are mild and will resolve with removal of the offending drug alone.
After stopping all serotonergic drugs, management is largely supportive and aimed at preventing complications.
Patients frequently require sedation, which is best facilitated with benzodiazepines.
Antipsychotics should be avoided because of their anticholinergic properties, which may inhibit sweating and heat dissipation.

Myasthenia gravis (MG) is an organ-specific autoimmune disease caused by an antibody-mediated assault on the muscle nicotinic acetylcholine receptor (AChR) at the neuromuscular junction. Binding of antibodies to the AChR leads to loss of functional AChRs and impairs the neuromuscular signal transmission, resulting in muscular weakness.

Reactive arthritis, (formerly known as Reiter’s syndrome), is an autoimmune condition that occurs after a bacterial infection of the gastrointestinal or urinary tract. It is categorized as a seronegative spondylarthritis because of its association with HLA-B27. Reactive arthritis primarily affects young men and usually presents with musculoskeletal or extra‑articular symptoms. The characteristic triad consists of arthritis, conjunctivitis, and urethritis. Symmetric lower limb arthropathy and a sterile joint aspirate points towards reactive arthropathy.

The major endocrine functions of adrenal gland are to produce catecholamines and steroids. Catecholamine, synthesized by the adrenal medulla, is responsible for blood pressure and blood flow regulation whereas steroids produced by the cortex control energy and water homeostasis and immune responses. Glucocorticoids, a major group of adrenal steroids, have a stimulatory effect on catecholamine synthesis in the medulla.

Temazepam is an orally available benzodiazepine used in the therapy of insomnia.
The soporific activity of the benzodiazepines is mediated by their ability to enhance gamma-aminobutyric acid (GABA) mediated inhibition of synaptic transmission through binding to the GABA-A receptor.
The recommended initial dose for insomnia is 7.5 mg before bedtime, increasing as needed to a maximum dose of 30 mg.

The most common side effects of temazepam are dose-related and include daytime drowsiness, lethargy, ataxia, dysarthria, and dizziness.
Tolerance develops to these side effects, but tolerance may also develop to the effects on insomnia.

Lewy body dementia is an increasingly recognised cause of dementia, accounting for up to 20% of cases. The characteristic pathological feature is alpha-synuclein cytoplasmic inclusions (Lewy bodies) in the substantia nigra, paralimbic and neocortical areas. Neuroleptics should be avoided in Lewy body dementia as patients are extremely sensitive and may develop irreversible parkinsonism. Questions may give a history of a patient who has deteriorated following the introduction of an antipsychotic agent.

Bulimia nervosa is a serious, potentially life-threatening eating disorder characterized by a cycle of bingeing and compensatory behaviours such as self-induced vomiting designed to undo or compensate for the effects of binge eating.

According to the DSM-5, the official diagnostic criteria for bulimia nervosa are:
Recurrent episodes of binge eating. An episode of binge eating is characterized by both of the following:
Eating, in a discrete period of time (e.g. within any 2-hour period), an amount of food that is definitely larger than most people would eat during a similar period of time and under similar circumstances.
A sense of lack of control over eating during the episode (e.g. a feeling that one cannot stop eating or control what or how much one is eating).
Recurrent inappropriate compensatory behaviour in order to prevent weight gain, such as self-induced vomiting, misuse of laxatives, diuretics, or other medications, fasting, or excessive exercise.
The binge eating and inappropriate compensatory behaviours both occur, on average, at least once a week for three months.
Self-evaluation is unduly influenced by body shape and weight.
The disturbance does not occur exclusively during episodes of anorexia nervosa.

Antidepressants as a group – particularly selective serotonin reuptake inhibitors (SSRIs) – are the mainstay of pharmacotherapy for bulimia nervosa. These may be helpful for patients with substantial concurrent symptoms of depression, anxiety, obsessions, or certain impulse disorder symptoms. They may be particularly good for patients who have not benefited from or had suboptimal response to suitable psychosocial therapy or who have a chronic, difficult course in combination with other treatments.

Food and Drug Administration (FDA) approved treatments
Fluoxetine (Prozac): Initial dose 20 mg/d with advance over 1–2 weeks to 60 mg/d in the morning as tolerated. Some patients may need to begin at a lower dose if side effects are intolerable. A maximum dose of 80 mg/d may be used in some cases.

Uhthoff’s phenomenon is worsening of vision following a rise in body temperature.
Lhermitte’s sign describes paraesthesia in the limbs on neck flexion.
Oppenheim’s sign is seen when scratching of the inner side of leg leads to extension of the toes. It is a sign of cerebral irritation and is not related to multiple sclerosis.
Werdnig-Hoffman’s disease is also known as spinal muscular atrophy.

Lead can be absorbed through the skin and by inhalation. It is associated with iron deficiency and a microcytic anaemia. The most common gastrointestinal symptoms are abdominal colic and constipation.

The size of the kidneys on ultrasound would differentiate chronic from acute renal failures. Chronic renal failure is more associated with small-sized kidneys.

Campylobacter is the most likely cause of diarrheal illness often due to undercooked meat being ingested. It is also a major cause of traveller’s diarrhoea. Sufficient fluid replacement and anti-emetics are indicated first followed by the antibiotic, Erythromycin although antibiotic treatment in adults is still in question. Ciprofloxacin and Tetracycline may also be effective.

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.
The boy most probably has nephrogenic diabetes insidious (DI) not central DI so he is not responding to the ADH treatment.

Ramipril is an ACE inhibitor that blocks the conversion of angiotensin I to angiotensin II as well as preventing the breakdown of bradykinin, leading to blood vessel dilatation and decreased blood pressure. However, bradykinin also causes smooth muscles in the lungs to contract, so the build-up of bradykinin is thought to cause the dry cough that is a common side-effect in patients that are on ACE inhibitors.