Dapagliflozin works by inhibiting sodium glucose cotransporter 2 (SGLT2) and blocking resorption of glucose in the kidney, leading to an increase in urinary glucose excretion and lowering of both plasma glucose levels and body weight.
All studies with SGLT2 inhibitors have found significant reductions in BP, with greater reductions seen in systolic (1.66 to 6.9mmHg) than diastolic (0.88 to 3.5mmHg) BP.
While some trials have shown no change in lipid parameters, others have shown a modest but statistically significant increase in both HDL and LDL cholesterol with no effect on triglycerides or the LDL/HDL ratio.

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.

Azathioprine therapy can cause acute myelosuppression. Toxicity is in part caused by the incorporation of azathioprine-derived 6-thioguanine nucleotides (6-TGN) into deoxyribonucleic acid (DNA). The enzyme thiopurine methyltransferase (TPMT) plays an important role in azathioprine catabolism.

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.

This man has gingivostomatitis, a characteristic feature of primary herpes simplex virus infection. Herpetic gingivostomatitis is often the initial presentation during the first (primary) herpes simplex infection. It is of greater severity than herpes labialis (cold sores) which is often the subsequent presentations. Primary herpetic gingivostomatitis is the most common viral infection of the mouth.
Primary herpetic gingivostomatitis (PHGS) is caused predominantly by HSV-1 and affects mainly children. Prodromal symptoms, such as fever, anorexia, irritability, malaise and headache, may occur in advance of disease. Sub-mandibular lymphadenitis, halitosis and refusal to drink are usual concomitant findings.

Occupational asthma (OA) could be divided into a nonimmunological, irritant-induced asthma and an immunological, allergy-induced asthma. In addition, allergy-induced asthma can be caused by two different groups of agents: high molecular weight proteins (>5,000 Da) or low molecular weight agents (<5,000 Da), generally chemicals like the isocyanates.
Isocyanates are very reactive chemicals characterized by one or more isocyanate groups (–N=C=O). The main reactions of this chemical group are addition reactions with ethanol, resulting in urethanes, with amines (resulting in urea derivates) and with water. Here, the product is carbamic acid which is not stable and reacts further to amines, releasing free carbon dioxide.

Diisocyanates and polyisocyanates are, together with the largely nontoxic polyol group, the basic building blocks of the polyurethane (PU) chemical industry, where they are used solely or in combination with solvents or additives in the production of adhesives, foams, elastomers, paintings, coatings and other materials.

The complex salts of platinum are one of the most potent respiratory sensitising agents having caused occupational asthma in more than 50% of exposed workers. Substitution of ammonium hexachlor platinate with platinum tetra amine dichloride in the manufacture of catalyst has controlled the problem in the catalyst industry. Ammonium hexachlorplatinate exposure still occurs in the refining process.

Rosin based solder flux fume is produced when soldering. This fume is a top cause of occupational asthma.

Bakeries, flour mills and kitchens where flour dust and additives in the flour are a common cause of occupational asthma.

Cadmium was not found to cause occupational asthma.

Euthyroid sick syndrome (also known as nonthyroidal illness syndrome) can be described as abnormal findings on thyroid function tests that occurs in the setting of a nonthyroidal illness (NTI), without pre-existing hypothalamic-pituitary and thyroid gland dysfunction. After recovery from an NTI, these thyroid function test result abnormalities should be completely reversible.
Multiple alterations in serum thyroid function test findings have been recognized in patients with a wide variety of NTIs without evidence of pre-existing thyroid or hypothalamic-pituitary disease. The most prominent alterations are low serum triiodothyronine (T3) and elevated reverse T3 (rT3), leading to the general term low T3 syndrome. Thyroid-stimulating hormone (TSH), thyroxine (T4), free T4 (FT4), and free T4 index (FTI) also are affected in variable degrees based on the severity and duration of the NTI. As the severity of the NTI increases, both serum T3 and T4 levels drop, but they gradually normalize as the patient recovers.
Reverse T3 is used to differentiate between this condition and secondary thyroid failure.

The symptoms of ataxia, slurred speech and blurred vision are all suggestive of phenytoin toxicity. Cimetidine increases the efficacy of phenytoin by reducing its hepatic metabolism.

Phenytoin has a narrow therapeutic index (10-20 mg/L) and its levels are monitored by measuring the total phenytoin concentration.
Cimetidine is an H2 receptor antagonist used in the treatment of peptic ulcers. It acts by decreasing gastric acid secretion.
Cimetidine also has an inhibitory effect on several isoforms of the cytochrome enzyme system including the CYP450 enzymatic pathway. Phenytoin is metabolized by the same cytochrome P450 enzyme system in the liver.
Thus, the simultaneous administration of both these medications leads to an inhibition of phenytoin metabolism and thus increases its circulating levels leading to phenytoin toxicity.

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.

Pneumothorax is defined as air in the pleural space and may be classified as spontaneous, traumatic or iatrogenic. Primary spontaneous pneumothorax occurs in patients without clinically apparent lung disease.
Primary pneumothorax has an incidence of 18-28 per 100,000 per year for men and 1.2-6 per 100,000 per year for women. Most patients present with ipsilateral pleuritic chest pain and acute shortness of breath. Shortness of breath is largely dependent on the size of the pneumothorax and whether there is underlying chronic lung disease.

Young patients may have chest pain only. Most episodes of pneumothorax occur at rest. Symptoms may resolve within 24 hours in patients with primary spontaneous pneumothorax. The diagnosis of a pneumothorax is confirmed by finding a visceral pleural line displaced from the chest wall, without distal lung markings, on a posterior-anterior chest radiograph.

Breathless patients should not be left without intervention regardless of the size of pneumothorax. If there is a rim of air >2cm on the chest X-ray, this should be aspirated.
Aspiration is successful in approximately 70 per cent of patients; the patient may be discharged subsequently. A further attempt at aspiration is recommended if the patient remains symptomatic and a volume of less than 2.5 litres has been aspirated on the first attempt.

If unsuccessful, an intercostal drain is inserted. This may be removed after 24 hours after full re-expansion or cessation of air leak without clamping and discharge may be considered.

Throughout pregnancy the tubular reabsorption of glucose is less effective than in the non-pregnant state, this leads to glycosuria.

TNF-alpha inhibitors are known to ameliorate the symptoms and disease activity of Arthritis mutilans (a rare and severe form of psoriatic arthritis), by disabling the cytokines that are involved in inflammation and joint destruction. From the mentioned choices, this would be the most effective option. Methotrexate is the most commonly used DMARD, followed by sulfasalazine used in mild to moderate forms of psoriatic arthritis but has not shown much efficacy in arthritis mutilans. Phototherapy, narrowband UVB light therapy can be very effective in clearing skin lesions.

A cohort study is a particular form of longitudinal study that samples a cohort (a group of people who share a defining characteristic, typically those who experienced a common event in a selected period, such as birth or graduation), performing a cross-section at intervals through time.
The relative risk (RR) or risk ratio is the ratio of the probability of an outcome in an exposed group to the probability of an outcome in an unexposed group. Relative risk is used in the statistical analysis of the data of experimental, cohort and cross-sectional studies, to estimate the strength of the association between treatments or risk factors, and outcomes.

CMV infection is usually asymptomatic in adults. However, if the mother is infected for the first time during pregnancy then there is high chances of this infection passing on to the foetus. CMV infection can cause blindness, deafness, learning difficulties, restricted growth etc. Hepatitis B, herpes simplex, syphilis and HIV do not present with these classical signs of CMV infection in new-borns. It is estimated that 10 stillbirths occur in England and Wales every year due to CMV infection. The foetus is most at risk in early pregnancy. There is no effective prevention.

Because of the patient’s history of excessive alcohol consumption, there is a strong suspicion of alcoholic peripheral neuropathy. In the UK, alcohol abuse and diabetes are the most common causes of peripheral neuropathy.

This patient has complaints of diplopia in the right eye, when looking towards the right. Eyeball movements towards the right side are controlled by right lateral rectus muscle which is supplied by the abducent nerve.

Malingering is not considered a mental illness. In the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), malingering receives a V code as one of the other conditions that may be a focus of clinical attention. The DSM-5 describes malingering as the intentional production of false or grossly exaggerated physical or psychological problems. Motivation for malingering is usually external (e.g., avoiding military duty or work, obtaining financial compensation, evading criminal prosecution, or obtaining drugs).

Malingering should be strongly suspected if any combination of the following factors is noted to be present: (1) medicolegal context of presentation; (2) marked discrepancy between the person’s claimed stress or disability and the objective findings; (3) lack of cooperation during the diagnostic evaluation and in complying with the prescribed treatment regimen; and (4) the presence in the patient of antisocial personality disorder (ASPD).

This patient is be pretending to be sick in order to get morphine.

The normal partial pressure reference values are: oxygen PaO2 more than 80 mmHg (11 kPa), and carbon dioxide PaCO2 lesser than 45 mmHg (6.0 kPa).
This patient has an elevated PaCO2 of 6.8kPa which exceeds the normal value of less than 6.0kPa.
The pH is also lower than 7.35 at 7.32

In any patient with asthma, an increasing PaCO2 indicates severe airway obstruction that is leading to respiratory muscle fatigue and patient exhaustion.

According to the British Thoracic Society guidelines:
Indications for admission to intensive care or high-dependency units include
patients requiring ventilatory support and those with acute severe or life-threatening asthma who are failing to respond to therapy, as evidenced by:
• deteriorating PEF
• persisting or worsening hypoxia
• hypercapnia
• arterial blood gas analysis showing fall in pH or rising hydrogen concentration
• exhaustion, feeble respiration
• drowsiness, confusion, altered conscious state
• respiratory arrest

Transfer to ICU accompanied by a doctor prepared to intubate if:
• Deteriorating PEF, worsening or persisting hypoxia, or hypercapnia
• Exhaustion, altered consciousness
• Poor respiratory effort or respiratory arrest

A single dose of intravenous magnesium sulphate is safe and may improve lung function and reduce intubation rates in patients with acute severe asthma. Intravenous magnesium sulphate may also reduce hospital admissions in adults with acute asthma who have had little or no response to standard treatment.

Consider giving a single dose of intravenous magnesium sulphate to
patients with acute severe asthma (PEF <50% best or predicted) who have not had a good initial response to inhaled bronchodilator therapy.
Magnesium sulphate (1.2–2 g IV infusion over 20 minutes) should only be used following consultation with senior medical staff.

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.

Syringomyelia is a development of a cavity (syrinx) within the spinal cord. Signs and symptoms include loss of feeling, paralysis, weakness, and stiffness in the back, shoulders, and extremities. Syringomyelia may also cause a loss of the ability to feel extremes of hot or cold, especially in the hands. Symptoms typically vary depending on the extent and, often more critically, on the location of the syrinx within the spinal cord.

The human cell has two type of DNA: Nuclear DNA and Mitochondrial DNA (MtDNA). A MtDNA copy is passed down entirely unchanged, through the maternal line. Males cannot pass their MtDNA to their offspring although they inherit a copy of it from their mother. Mitochondrial inheritance therefore has the following characteristics:
– Inheritance is only via the maternal line
– All children of affected males will not inherit the disease
– All children of affected females will inherit it

The classic history in this high risk patient is suggestive of a dissecting aortic aneurysm. His transoesophageal echocardiogram confirms the diagnosis. ST elevation in ECG is probably due to the extension of the dissection of the aorta which results in compromised coronary blood supply.

The most likely diagnosis is idiopathic Parkinson’s disease because of the unilateral presentation. In addition, cogwheel rigidity is a classic presenting symptom. Neuroleptic-induced parkinsonism is usually bilateral and symmetrical. Essential tremors do not cause rest tremors.

Hypotensive effect of streptokinase occurs during the streptokinase infusion which is usually transient. Acute mitral regurgitation due to rupture of papillary muscles, ventricular septal defects and reinfarctions (left or right) are known to cause hypotension after 24 hrs. Pulmonary embolism is less likely but cannot be excluded.

Carbon monoxide (CO) is a colourless, odourless gas produced by incomplete combustion of carbonaceous material. Clinical presentation in patients with CO poisoning ranges from headache and dizziness to coma and death. Hyperbaric oxygen therapy can significantly reduce the morbidity of CO poisoning, but a portion of survivors still suffer significant long-term neurologic and affective sequelae.

Complaints:
Malaise, flulike symptoms, fatigue
Dyspnoea on exertion
Chest pain, palpitations
Lethargy
Confusion
Depression
Impulsiveness
Distractibility
Hallucination, confabulation
Agitation
Nausea, vomiting, diarrhoea
Abdominal pain
Headache, drowsiness
Dizziness, weakness, confusion
Visual disturbance, syncope, seizure
Faecal and urinary incontinence
Memory and gait disturbances
Bizarre neurologic symptoms, coma

Vital signs may include the following:
Tachycardia
Hypertension or hypotension
Hyperthermia
Marked tachypnoea (rare; severe intoxication often associated with mild or no tachypnoea)
Although so-called cherry-red skin has traditionally been considered a sign of CO poisoning, it is in fact rare.

The clinical diagnosis of acute carbon monoxide (CO) poisoning should be confirmed by demonstrating an elevated level of carboxyhaemoglobin (HbCO). Either arterial or venous blood can be used for testing. Analysis of HbCO requires direct spectrophotometric measurement in specific blood gas analysers. Elevated CO levels of at least 3–4% in non-smokers and at least 10% in smokers are significant.

Heterochromia (difference in iris colour) is seen in congenital Horner’s syndrome, as well as anhidrosis. Other features of non-congenital Horner’s include miosis, ptosis and enophthalmos.

Hypopyon can be seen in anterior uveitis, however the combination of a normal pupillary reaction and contact lens use make a diagnosis of keratitis more likely. Keratitis describes inflammation of the cornea, and features include red eye with pain and erythema, photophobia, and foreign body/gritty sensation.

Stopping smoking is the single most effective non-pharmacological intervention which will reduce future ischaemic events. But the rest of the responses are also important interventions with regards to reducing future ischaemic events.

Hydroxychloroquine is used in the management of SLE as it prevents disease progression and has relatively mild side effects, for instance headache, nausea etc. Its use reduces the usage of corticosteroids. It is particularly effective when the disease is less severe and there is no organ involvement. Cyclophosphamide and prednisolone are indicated in cases of renal, neurological and lung involvement.

The patient’s symptoms are suggestive of ankylosing spondylitis which is often accompanied by iritis, the cause of this patient’s red eye.