Multiple myeloma is a clonal abnormality affecting plasma cells in which there is an overproduction of functionless immunoglobulins. The most common patient complaint is bone pain, especially in the back and ribs. Anaemia and renal failure are common, along with hypercalcemia. Hypercalcemia may lead to an altered mental status, as in this case. Chronic lymphocytic leukaemia occurs due to the overproduction of lymphocytes, usually B cells. CLL may present with an asymptomatic elevation of B cells. Patients are generally more than 50 years old and present with non-specific fatigue and weight loss symptoms.There is no history of alcohol abuse in this case. Furthermore, patients with a history of alcohol abuse may have signs of liver failure, which are not present here. Metastatic prostate cancer would most often cause lower backache as it metastasises first to the lumbar spine via the vertebral venous plexus. A patient with Vitamin B12 deficiency would have anaemia, megaloblastic, hypersegmented neutrophils, and signs of peripheral neuropathy.

Decreased blood volume stimulates the secretion of renin (because of decreased renal perfusion pressure) and initiates the renin-angiotensin-aldosterone cascade. Angiotensin-converting enzyme (ACE) inhibitors block the cascade by decreasing the production of angiotensin. Hyperosmolarity stimulates antidiuretic hormone (ADH) [not aldosterone] secretion. Hyperkalaemia, not hypokalaemia, directly stimulates aldosterone secretion by the adrenal cortex. ANP inhibits renin secretion, thereby inhibiting the production of angiotensin and aldosterone.

In February 2016 the Society of Critical Care Medicine published a JAMA article reformatting the definitions of sepsis in an attempt to overcome the shortcomings of the old definitions.The main changes are a new definition of sepsis, the replacement of the SIRS criteria with the quick Sepsis-related Organ Failure Assessment (qSOFA), and the complete removal of “severe sepsis” as an entity.The new definition of sepsis is that it is “life-threatening organ dysfunction caused by a dysregulated host response to infection.”Septic shock is “a subset of sepsis in which underlying circulatory and cellular metabolism abnormalities are profound enough to increase mortality.”In essence this means that septic shock is sepsis plus the following, despite adequate fluid resuscitation:Vasopressors required to maintain a MAP > 65 mmHgSerum lactate > 2 mmol/lThe qSOFA score is a bedside prompt designed to identify patients with suspected infection who are at greater risk for a poor outcome outside of the intensive care unit. It uses the following three criteria:Hypotension (SBP < 100 mmHg)Tachypnoea (RR > 22)Altered mental status (GCS < 15)The presence of 2 or more of the qSOFA criteria near the onset of infection is associated with greater risk of death or a prolonged intensive care unit stay.

Heparin acts as an anticoagulant by enhancing the inhibition rate of clotting proteases by antithrombin III impairing normal haemostasis and inhibition of factor Xa. Low molecular weight heparins have a small effect on the activated partial thromboplastin time and strongly inhibit factor Xa. Enoxaparin is derived from porcine heparin that undergoes benzylation followed by alkaline depolymerization.

External (lateral) rotation at the hip joint is produced by the gluteus maximus together with a group of 6 small muscles (lateral rotators): piriformis, obturator internus, superior and inferior gemelli, quadratus femoris and obturator externus.

Fetal haemoglobin is the most common type of haemoglobin found in the foetus during pregnancy. It transports oxygen from the maternal circulation to the fetal circulation. It can easily bind to oxygen from the maternal circulation because it has a high affinity for oxygen. From 10 to 12 weeks of pregnancy to the first six months after birth, the erythroid precursor cells produce fetal haemoglobin. In comparison to adult haemoglobin, fetal haemoglobin has two alpha and two gamma subunits, whereas adult haemoglobin has two alpha and two beta subunits in its major form. And, unlike adult haemoglobin, the oxygen dissociation curve of fetal haemoglobin is left-shifted. Myoglobin is an oxygen storage molecule with a very high affinity for oxygen. Only when the partial pressure of oxygen is exceeded does it release oxygen.

Diabetes ketoacidosis is an acute complication of diabetes mellitus. Insulin is administered to achieve euglycemia, and crystalloids or colloidal solution is administered to achieve euvolemia and euelectrolytaemia. Potassium levels severely fluctuate during the treatment of DKA, hypokalaemia being more common. Insulin promotes the cell to take up potassium from the extracellular space via increased sodium-potassium pump activity. It is important to monitor potassium levels during the treatment of DKA regularly. It is widely suggested that the normal saline shall be used for initial resuscitation, and once the potassium level is retrieved, the patient can be started on potassium replacement should the serum potassium level be between 3.3 and 4.5 mmol/L If potassium levels fall below 3.3 mmol/l, insulin administration may need to be interrupted to correct the hypokalaemia.

End-organ damage (e.g. encephalopathy, intracranial haemorrhage, acute myocardial infarction or ischaemia, dissection, pulmonary oedema, nephropathy, eclampsia, papilledema, and/or angiopathic haemolytic anaemia) characterises a hypertensive emergency (also known as ‘accelerated hypertension’ or malignant hypertension’ It’s a life-threatening condition that necessitates rapid blood pressure reduction to avoid end-organ damage and a negative outcome.In the presence of cardiac ischaemia, hypertensive emergencies require immediate treatment to prevent myocardial infarction. Similarly, if myonecrosis occurs in the presence of an existing infarction, prompt treatment is required to prevent further myonecrosis. When thrombolysis is used as the primary reperfusion therapy for acute myocardial infarction, blood pressure control is especially important.An intravenous nitrate is the drug of choice in this situation (e.g. GTN). These have a dual purpose in that they can help patients with ischaemic chest pain manage their symptoms. Because lowering blood pressure with nitrates isn’t always enough to achieve optimal results, intravenous beta-blockers are frequently used as a supplement. For this, intravenous atenolol and metoprolol are commonly used.

Bartter’s syndrome is an autosomal recessive renal tubular disorder characterized by hypokalaemia, hypochloraemia, metabolic alkalosis, and hyperreninemia with normal blood pressure. The underlying kidney abnormality results in excessive urinary losses of sodium, chloride, and potassium. Bartter’s syndrome does not cause an elevated potassium level, but instead causes a decrease in its concentration (hypokalaemia). The other choices are causes of hyperkalaemia or elevated potassium levels. Renal failure, Addison’s disease (adrenal insufficiency), congenital adrenal hyperplasia, renal tubular acidosis (type 4), rhabdomyolysis, burns and trauma, tumour syndrome, and acidosis are non-drug causes of hyperkalaemia. On the other hand, drugs that can cause hyperkalaemia include ACE inhibitors, angiotensin receptor blockers, NSAIDs, beta-blockers, digoxin, and suxamethonium.

To avoid the spread of infection, infected patients should be isolated. All lesions should be crusted over before children return to nursery or school, even if the standard exclusion time is 5 days.