A t test is a type of statistical test that is used to compare the means of two groups. It is one of the most widely used statistical hypothesis tests in pain studies. There are two types of statistical inferences: parametric and nonparametric methods. Parametric methods refer to a statistical technique in which one defines the probability distribution of probability variables and makes inferences about the parameters of the distribution. In cases in which the probability distribution cannot be defined, nonparametric methods are employed. T tests are a type of parametric method; they can be used when the samples satisfy the conditions of normality, equal variance, and independence. In this case the data is parametric, comparing two independent samples from the same population.

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.

Chloride channels are involved in a diverse set of functions in normal physiology and acquired diseases. Additionally, there are genetic diseases caused by mutations in chloride channels (channelopathies) — the most common being cystic fibrosis, which has a prevalence of 1 in 2,000 Caucasians.

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.

Pneumococcal meningitis is the most common and severe form of bacterial meningitis. Fatality rates are substantial, and long-term sequelae develop in about half of survivors. Disease outcome has been related to the severity of the proinflammatory response in the subarachnoid space. The complement system, which mediates key inflammatory processes, has been implicated as a modulator of pneumococcal meningitis disease severity in animal studies. C5 fragment levels in cerebrospinal fluid (CSF) of patients with bacterial meningitis correlated with several clinical indicators of poor prognosis. The common terminal pathway consists of complement components C5–C9, and activation forms the anaphylatoxin C5a, a strong proinflammatory mediator, and the membrane attack complex (MAC), which creates pores in the bacterial cell wall (12). Deficiencies in these late complement components have been recognized as a cause of recurrent and familial meningococcal infections.

Lidocaine is an example of class IB antiarrhythmics.

The Vaughan-Williams classification of antiarrhythmics
I: Membrane stabilizing agents
IA: Quinidine, Procainamide, Disopyramide
IB: Lidocaine, Mexiletine
IC: Propafenone, Flecainide
II: β blockers – Propranolol, Esmolol
III: Agents widening AP – Amiodarone, Dronedarone, Dofetilide, Ibutilide, Sotalol
IV: Calcium channel blockers – Verapamil, Diltiazem
V: Miscellaneous – Digoxin, adenosine, magnesium

There are number of diseases that have to be notified to relevant authorities to prevent or reduce their spread. Those conditions include Cholera, Diphtheria, Food poisoning, Infectious bloody diarrhoea, Malaria, Measles, Meningococcal septicaemia, Mumps, Plague, Rabies and Rubella.

Carbimazole is used to treat hyperthyroidism. Carbimazole is a pro-drug as after absorption it is converted to the active form, methimazole. Methimazole prevents thyroid peroxidase enzyme from coupling and iodinating the tyrosine residues on thyroglobulin, hence reducing the production of the thyroid hormones T3 and T4 (thyroxine).

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.

Post-primary pulmonary tuberculosis is a chronic disease commonly caused by either endogenous reactivation of a latent infection or exogenous re-infection by Mycobacterium tuberculosis.
Post-primary pulmonary tuberculosis (also called reactivation tuberculosis) develops in 5%–20% of patients infected with M. tuberculosis.

Found mainly in adults, this form of tuberculosis arises from the reactivation of bacilli that lay dormant within a fibrotic area of the lung. In adults, reinfection with a strain of mycobacterium that differs from that which caused the primary infection is also possible. Predisposing factors include immunosuppression, diabetes, malnutrition and alcoholism.

Infliximab is a monoclonal antibody against tumour necrosis factor α (TNF-α). It is FDA approved for many autoimmune conditions, including rheumatoid arthritis and Crohn’s disease. One of the many known side effects of infliximab therapy is reactivation of latent tuberculosis (TB). Because of the resemblances in clinical and radiological features, tubercular lesions in the lung may mimic malignancy. TB accounts for 27% of all infections initially presumed to be lung cancer on imaging studies.

Glomerulosclerosis is the scarring and hardening of the glomeruli known as diabetic glomerulosclerosis occurring in long-standing diabetes.

Hypovitaminosis B1, consistent with dry beriberi is crucially a treatable condition, although sometimes with incomplete recovery, but it is probably under-recognized yet increasingly common given increasing levels of alcohol abuse in the western world. Dry beriberi or ‘acute nutritional polyneuropathy’ is considered to be rare in the western world. Rapid deterioration can occur, typically with weakness, paraesthesia and neuropathic pain. Striking motor nerve involvement can occur, mimicking Guillain-Barré syndrome (GBS). In the context of increasing alcohol abuse in the western world, it is possible that alcoholic neuropathy associated with abrupt deterioration due to concomitant nutritional hypovitaminosis B1 may be seen increasingly often.

Specificity (negative in health)
The ability of a test to correctly classify an individual as disease- free is called the test′s specificity. [Table 2]

Specificity = d / b+d

= d (true negative) / b+d (true negative + false positive)

= Probability of being test negative when disease absent.

Example: One hundred persons with normal angles (diagnosed by ′gold standard′: gonioscopy) are examined by peripheral angle chamber depth examination. Eighty-five persons had normal peripheral angle chamber depth [Table 3]. The specificity of the peripheral angle chamber depth examination to PACG is therefore –

85 / 100 = 85%.

Osteomalacia is a condition due to defective mineralization of osteoid. Occurs as a result of Vitamin D deficiency secondary to poor dietary intake and sun exposure, malabsorption e.g., inflammatory bowel disease and gastrointestinal bypass surgery. Radiological findings include reduced bone mineral density (a non specific finding), inability to radiologically distinguish vertebral body trabeculae (the film appears poor quality), looser pseudo fractures, fissures, or narrow radiolucent lines (these are the characteristic findings). Osteolytic or punched out lesions may be seen with multiple myeloma and bony metastases. Areas of sclerosis may be observed with conditions like osteosclerosis and Paget disease. A Brodie abscess is a subacute osteomyelitis, which may persist for years before progressing to a chronic, frank osteomyelitis.

It should be noted that as a general rule 5-HT receptor agonists are used in the acute treatment of migraine whilst 5-HT receptor antagonists are used in prophylaxis. NICE produced guidelines in 2012 on the management of headache, including migraines. Prophylaxis should be given if patients are experiencing 2 or more attacks per month. Modern treatment is effective in about 60% of patients. NICE advises either topiramate or propranolol ‘according to the person’s preference, comorbidities and risk of adverse events’. Propranolol should be used in preference to topiramate in women of child bearing age as it may be teratogenic and it can reduce the effectiveness of hormonal contraceptives.

Klinefelter syndrome (KS), the most common human sex chromosome disorder 47,XXY. It is characterized by hypogonadism (micro-orchidism, oligospermia/azoospermia) and gynecomastia in late puberty. If Klinefelter syndrome is not diagnosed prenatally, a patient with 47,XXY karyotype may demonstrate various subtle, age-related clinical signs that would prompt diagnostic testing. These include the following:
Infants: Hypospadias, small phallus, cryptorchidism.
Toddlers: Developmental delay (especially expressive language skills), hypotonia.
Older boys and adolescent males: Tall stature; delayed or incomplete pubertal development with eunuchoid body habitus; gynecomastia; small, firm testes; sparse body hair.

From childhood with progression to early puberty, the pituitary-gonadal function observed is within normal limits for 47,XXY males.
At mid puberty and later, follicle-stimulating hormone (FSH) and luteinizing hormone (LH) concentrations rise to hyper-gonadotropic levels, inhibin B levels fall until they are undetectable, and testosterone levels are at low or low-normal levels after an initial increase.

Fragile X syndrome, also termed Martin-Bell syndrome or marker X syndrome, is the most common cause of inherited mental retardation, intellectual disability, and autism.
However, the patient here does not have any mental disabilities as he already works as a clerk, and that too would make Down’s Syndrome less likely.

Classic Kallmann syndrome (KS) and idiopathic hypogonadotropic hypogonadism (IHH) are rare genetic conditions that encompass the spectrum of isolated hypogonadotropic hypogonadism. Most patients have gonadotropin-releasing hormone (GnRH) deficiency, as suggested by their response to pulsatile GnRH therapy. Hypothalamic-pituitary function is otherwise normal in most patients, and hypothalamic-pituitary imaging reveals no space-occupying lesions. By definition, either anosmia or severe hyposmia is present in patients with Kallmann syndrome, in contrast to patients with idiopathic hypogonadotropic hypogonadism, whose sense of smell is normal.

The diagnosis for the aforementioned case is thrombotic thrombocytopenic purpura (TTP). TTP is classically characterised as a pentad of thrombocytopaenia, microvascular haemolysis, fluctuating neurological signs, renal impairment, and fever.

The differential diagnosis for severe thrombocytopaenia is immune thrombocytopenic purpura (ITP). ITP is more common than TTP. However, a patient of ITP would not present with the range of symptoms seen in this scenario.

In TTP, there is deficiency of a protease which breaks down large multimers of von Willebrand factor. This leads to abnormally large and sticky multimers of von Willebrand factor which cause platelets to clump within the vessels.

Untreated TTP has a mortality rate of up to 90%. Therefore, rapid plasma exchange (PEX) may be a life-saving intervention. Platelet transfusion in TTP is only indicated if there is an ongoing life-threatening bleed. Intravenous methylprednisolone is indicated after treatment with PEX has been completed. There is no current role of intravenous immunoglobulin in the routine management of TTP. However, there have been reports of its successful use in PEX- and steroid-refractory cases. Intravenous argatroban is indicated in heparin-induced thrombocytopaenia (HIT), but there is no history of recent heparin administration or hospitalisation in this patient nor are the clinical signs consistent with HIT.

Management options for TTP include PEX as the treatment of choice. Steroids and immunosuppressants are also given. Antibiotics are not recommended as they may worsen the outcome of the disease. For cases resistant to PEX and pharmacologic therapy, vincristine is given.

There are two types of Non-alcoholic fatty liver disease (NAFLD); simple fatty liver and non-alcoholic steatohepatitis (NASH). Simple fatty liver and NASH are two separate conditions.
Simple fatty liver, also called non-alcoholic fatty liver (NAFL), is a form of NAFLD in which you have fat in your liver but little or no inflammation or liver cell damage. Simple fatty liver typically does not progress to cause liver damage or complications.
Non-alcoholic steatohepatitis (NASH)
NASH is a form of NAFLD in which you have hepatitis and liver cell damage, in addition to fat in your liver. Inflammation and liver cell damage can cause fibrosis, or scarring, of the liver. NASH may lead to cirrhosis or liver cancer. Type I diabetes is not associated with NASH (non-alcoholic steatohepatitis), but type II diabetes is. Hyperlipidaemia, obesity, sudden weight loss/starvation and jejunoileal bypass are all associated with NASH. This is the most common cause of liver disease in the developed world.

Serum vitamin D levels are influenced by sun exposure and diet. Cod liver oil is an important dietary vitamin D source in high-latitude countries like Norway where there is no sun-induced vitamin D production during the winter. 14 Norwegian Health Authorities have recommended 5 ml of cod liver oil daily (400 IU of vitamin D) for more than 60 years to prevent diseases like rickets, formerly more prevalent in areas with little access to vitamin D-rich fatty fish.

Escherichia coli (also known as E. coli) is a gram-negative, facultatively anaerobic, rod-shaped bacterium commonly found in the lower intestine of warm-blooded organisms. Most E. coli strains are harmless, but some serotypes can cause serious food poisoning in their hosts, and are occasionally responsible for product recalls due to food contamination. The harmless strains are part of the normal flora of the gut, and can benefit their hosts by producing vitamin K2, and preventing colonization of the intestine with pathogenic bacteria. Virulent strains can cause gastroenteritis, urinary tract infections, and neonatal meningitis.
The most common causes of neonatal meningitis is bacterial infection of the blood, known as bacteremia (specifically Group B Streptococci (GBS; Streptococcus agalactiae), Escherichia coli, and Listeria monocytogenes). Although there is a low mortality rate in developed countries, there is a 50% prevalence rate of neurodevelopmental disabilities in E. coli and GBS meningitis

This girl most probably has Turner’s syndrome, which is caused by the absence of one set of genes from the short arm of one X chromosome.
Turner syndrome is a lifelong condition and needs lifelong oestrogen replacement therapy. Oestrogen is usually started at age 12-15 years. Treatment can be started with continuous low-dose oestrogens. These can be cycled in a 3-weeks on, 1-week off regimen after 6-18 months; progestin can be added later.

In childhood, growth hormone therapy is standard to prevent short stature as an adult.

Fetal ovarian development seems to be normal in Turner syndrome, with degeneration occurring in most cases around the time of birth so pulsatile GnRH and luteinising hormone would be of no use.

According to the updated GMC guidelines, patient safety is more important than anything else, thus the correct thing to do is inform your colleague’s employing body.

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.)

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)

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

The patient presents with worsened renal condition from the last consultation when he was started on enalapril (an ACE inhibitor) so this medication should be stopped. Because there is also no fluid overload; furosemide, a diuretic, should also be stopped.

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 the hypersecretion of gastrin. Serum gastrin levels > 1000 and a pH < 2 are diagnostic of pancreatic gastrinoma. None of the other answer choices are a better answer than this. CT abdomen may potentially show a tumour, but this is not diagnostic for type.

An odds ratio (OR) is a measure of the association between an exposure and an outcome. The OR represents the odds that an outcome will occur given a particular exposure, compared to the odds of the outcome occurring in the absence of that exposure. Odds ratios are most commonly used in case-control studies, however they can also be used in cross-sectional and cohort study designs as well (with some modifications and/or assumptions). Where

a = Number of exposed cases

b = Number of exposed non-cases

c = Number of unexposed cases

d = Number of unexposed non-cases

OR=(a/c) / (b/d) = ad/bc

The history gives you a woman who is on inhaled steroid therapy. It is always a good idea for patients to rinse their mouths well after using inhaled steroids. Odynophagia (pain on swallowing) is a symptom of oesophageal candidiasis, which is the most likely answer given the steroids. Typically, you might see this in someone who is immunocompromised (classically, in HIV+ patients).

Lead poisoning is characterised by abdominal pain, fatigue, constipation, peripheral neuropathy (mainly motor), and blue lines on gum margin in 20% of the adult patients (very rare in children).

For diagnosis, the level of lead in blood is usually considered with levels greater than 10 mcg/dL being significant. Furthermore, the blood film shows microcytic anaemia and basophilic stippling of red blood cells. Urinary coproporphyrin is increased (urinary porphobilinogen and uroporphyrin levels are normal to slightly increased). Raised serum and urine levels of delta-aminolaevulinic acid may also be seen, making it sometimes difficult to differentiate from acute intermittent porphyria.