Vesicoureteral reflux is the condition when the urine flows backwards from the bladder into the kidneys, which is the most common cause of UTI in patients this age.

Oxycodone is a safer opioid to use in patients with moderate to end-stage renal failure.
Active metabolites of morphine accumulate in renal failure which means that long-term use is contraindicated in patients with moderate/severe renal failure.
These toxic metabolites can accumulate causing toxicity and risk overdose.
Oxycodone is mainly metabolised in the liver and thus safer to use in patients with moderate to end-stage renal failure with dose reductions.
Adverse effects:
Constipation is the most common overall side effect. Others include: asthenia, dizziness, dry mouth, headache, nausea, pruritus, etc.

Medications in renal failure:
Drugs to be avoided in patients with renal failure
Antibiotics: tetracycline, nitrofurantoin
NSAIDs
Lithium
Metformin
Drugs that require dose adjustment:
Most antibiotics including penicillin, cephalosporins, vancomycin, gentamicin, streptomycin
Digoxin, atenolol
Methotrexate
Sulphonylureas
Furosemide
Opioids
Relatively safe drugs:
Antibiotics: erythromycin, rifampicin
Diazepam
Warfarin

COPD is commonly associated with progressive hypoxemia. Oxygen administration reduces mortality rates in patients with advanced COPD because of the favourable effects on pulmonary hemodynamics.

Long-term oxygen therapy improves survival 2-fold or more in hypoxemic patients with COPD, according to 2 landmark trials, the British Medical Research Council (MRC) study and the US National Heart, Lung and Blood Institute’s Nocturnal Oxygen Therapy Trial (NOTT). Hypoxemia is defined as PaO2 (partial pressure of oxygen in arterial blood) of less than 55 mm Hg or oxygen saturation of less than 90%. Oxygen was used for 15-19 hours per day.

Therefore, specialists recommend long-term oxygen therapy for patients with a PaO2 of less than 55 mm Hg, a PaO2 of less than 59 mm Hg with evidence of polycythaemia, or cor pulmonale. Patients should be evaluated after 1-3 months after initiating therapy, because some patients may not require long-term oxygen.

The most probable cause for diarrhoea is pseudomembranous colitis which is caused by Clostridium difficile. Pseudomembranous colitis is an inflammatory disease of the colon where the antibiotic-induced change in the balance of normal gut flora allows overgrowth of C difficile. Any antibiotic can cause this but the chances are higher with ampicillin, clindamycin, fluoroquinolones, and cephalosporins.

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%.

Turner syndrome (TS) is one of the most common genetic disorders; occurs with an incidence of I: 2,500 female live births. It results from complete or partial chromosome X monosomy. TS is associated with abnormalities of the X chromosome and characteristic clinical features of short stature, gonadal dysgenesis, sexual developmental deficiencies, cardiac and/or renal defects, webbed neck, low-set ears, skeletal deformities including cubitus valgus, a propensity to ear infections and hearing deficits.

There is a high risk of bleeding due to recent surgery and heparin. So thrombolysis is not an option. The most appropriate management is percutaneous coronary intervention.

Melanocytic naevi are skin tumours produced by melanocytes. They usually present in childhood but increase during puberty. The mnemonic A-B-C-D, is used by institutions to assess for suspicion of malignancy. The letters stand for asymmetry, border, colour, and diameter. If a mole starts changing in size, colour, shape or, especially, if the border of a mole develops ragged edges or becomes larger than a pencil eraser, it would be an appropriate time to consult with a physician. Other warning signs include if it begins to crust over, bleed, itch, or become inflamed.

Among the given anti-epileptics the best drug that can be given in this patient is lamotrigine.
Topiramate, carbamazepine, phenytoin, and phenobarbital are all hepatic enzyme inducers and are associated with decreased effectiveness of the oral contraceptive (OCP) due to acceleration of the metabolism of oestrogens and progestogens.
If she is planning on pregnancy then registry studies suggest that lamotrigine would also be the best choice.
Other hepatic enzyme inducers include rifampicin, spironolactone, griseofulvin, etc.

The chronic asymptomatic carrier state is thought to be why there is continued appearance of the bacterium in human populations. As shedding of the organism is intermittent and sometimes at low levels, methods to detect it have been limited. The Salmonella typhi may be cultured from intestinal secretions, faeces or urine in chronic carriers and is recommended to confirm the diagnosis. Vi agglutination test can also be high in normal people in areas with typhoid endemic. Full blood count or blood culture would not be helpful to determine carrier status. Widal antigen test is unable to differentiate carriers from people with a hx of prior infection.

Retinal and cerebellar haemangiomas are key features of Von Hippel-Lindau syndrome. Retinal haemangiomas are bilateral in 25% of patients and may lead to vitreous haemorrhage. Von Hippel-Lindau (VHL) syndrome is an autosomal dominant condition predisposing to neoplasia. It is due to an abnormality in the VHL gene located on short arm of chromosome 3.

Acute angle closure glaucoma can manifests itself with severe headache, nausea or vomiting, very blurry or hazy vision, seeing rainbows or halos around lights and redness in the white part of the affected eye. It is caused by a rapid or sudden increase in pressure inside the eye – intraocular pressure (IOP). In order to establish the diagnosis and start treatment immediately, IOP should first be measured.

Over consumption of fluids, prolonged race duration and inadequate training all can predispose to acute hyponatraemia.
Mild symptoms include a decreased ability to think, headaches, nausea, and an increased risk of falls. Severe symptoms include confusion, seizures, and coma. Normal serum sodium levels are 135 – 145 mEq/liter (135 – 145 mmol/L). Hyponatremia is generally defined as a serum sodium level of less than 135 mEq/L and is considered severe when the level is below 120 mEq/L.
The correct treatment to give is hypertonic saline. Decompressive craniotomy would help alleviate raised intracranial pressure due to cerebral oedema however is not an appropriate first line treatment. Demeclocycline is used for SIADH and mannitol is more likely to be used in the context of traumatic brain injury.
Hyponatremia is corrected slowly, to lessen the risk of the development of central pontine myelinolysis (CPM), a severe neurological disease involving a breakdown of the myelin sheaths covering parts of nerve cells. During treatment of hyponatremia, the serum sodium (salt level in the blood) should not rise by more than 8 mmol/L over 24 hours.

Varicose eczema is a common problem, particularly in elderly patients due to stasis or blood pooling from insufficient venous return; the alternative name of varicose eczema comes from a common cause of this being varicose veins. It is often mistaken for cellulitis, but cellulitis is rarely bilateral and is painful rather than itchy.

European guidelines for the treatment of syndrome of inappropriate antidiuresis include the following recommendations for the management of moderate or profound hyponatremia:
– Restrict fluid intake as first-line treatment.
– Second-line treatments include increasing solute intake with 0.25–0.50 g/kg per day or a combination of low-dose loop diuretics and oral sodium chloride.
– Use of lithium, demeclocycline, or vasopressin receptor antagonists is not recommended.
Recommendations on the treatment of SIADH from an American Expert Panel included the following:
– If chronic, limit the rate of correction.
– Fluid restriction should generally be first-line therapy.
– Consider pharmacologic therapies if serum Na + is not corrected after 24-48 hr of fluid restriction or if the patient has a low urinary electrolyte free water excretion.
– Patients being treated with vaptans should not be on a fluid restriction initially.
– Water, 5% dextrose or desmopressin can be used to slow the rate of correction if the water diuresis is profound.

Rasburicase should be given prior to chemotherapy in order to reduce the risk of tumour lysis syndrome (TLS). Rasburicase is a recombinant version of urate oxidase which is an enzyme that metabolizes uric acid to allantoin. Allantoin is 5–10 times more soluble than uric acid, hence, renal excretion is more effective.

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.

Burkitt lymphoma is a high-grade B-cell neoplasm. There are two major forms:
1. Endemic (African) form: typically involves maxilla or mandible.
2. Sporadic form: abdominal (e.g. ileocaecal) tumours are the most common form. More common in patients with HIV.

Burkitt lymphoma is associated with the c-myc gene translocation, usually t(8;14). The Epstein-Barr virus (EBV) is strongly implicated in development of the African form of Burkitt lymphoma and to a lesser extent, the sporadic form.

Management of the lymphoma is with chemotherapy. This tends to produce a rapid response which may cause TLS.

With a clinical history of weight loss, smoking, drinking alcohol, and hematemesis, the most likely answer is gastric carcinoma (also a mass). Based on symptomatology alone this is more likely than gastric lymphoma, as she has many risk factors for adenocarcinoma and/or squamous cell carcinoma. Helicobacter gastritis would not likely present with the severity of symptoms, neither would benign gastric ulcers.

Cholecystokinin (CCK) was discovered in 1928 in jejunal extracts as a gallbladder contraction factor. It was later shown to be member of a peptide family, which are all ligands for the CCK1 and CCK2 receptors. CCK peptides are known to be synthetized in the small intestinal endocrine I-cells and cerebral neurons.

Streptococcus pneumonia is the chief causative organism for lobar pneumonia in this age group patients. Typically patients present with rusty coloured sputum and a cough. Pneumocystis jiroveci is responsible for causing pneumocystis pneumonia among immunocompromised patients.

Measles and chickenpox are spread by droplets. Thus, patients should be isolated.
Rheumatic fever and post-streptococcal glomerulonephritis are immune mediated diseases that don’t require isolation.
Herpetic gingivostomatitis spreads by direct transmission of infected secretions to the stratified squamous epithelium.
HSP is not an infectious disease.

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%)

Flashes of light, presence of floaters and loss of vision (often described as a black curtain closing in on the visual field) are symptoms that strongly indicate retinal detachment. The fundoscopy findings of retinal tears support this diagnosis. Therefore, surgery of retina must be done to treat this patient.

Atopic dermatitis is an allergic condition which is more apparent in those children who have a positive family history in their 1st or 2nd degree relatives. In some cases, there might be a positive history of bronchial asthma. The best treatment option in this case would be topical application of 1% hydrocortisone ointment to the affected areas of the child. We cannot prescribe a strong ointment to the face because it may lead to skin atrophy, telangiectasia and other steroid related topical complications.

Achondroplasia is a common cause of dwarfism. It is caused by a mutation in fibroblast growth factor receptor 3 (FGFR3). In normal development FGFR3 has a negative regulatory effect on bone growth. In achondroplasia, the mutated form of the receptor is constitutively active and this leads to severely shortened bones. The effect is genetically dominant, with one mutant copy of the FGFR3 gene being sufficient to cause achondroplasia, while two copies of the mutant gene are invariably fatal. A person with achondroplasia thus has a 50% chance of passing dwarfism to each of their offspring. People with achondroplasia can be born to parents that do not have the condition due to spontaneous mutation. It occurs as a sporadic mutation in approximately 80% of cases (associated with advanced paternal age) or it may be inherited as an autosomal dominant genetic disorder.
People with achondroplasia have short stature, with an average adult height of 131 centimeters (52 inches) for males and 123 centimeters (48 inches) for females.

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.

Colonoscopy screening should begin 10 years after the first diagnosis in ulcerative colitis, given the increased risk for colon cancer. Given that she has developed primary sclerosing cholangitis, her risk of colon cancer is even higher. Colonoscopy screening should occur at 3 year intervals in the second decade, 2 year intervals in the third decade, and 1 year intervals by the first decade, making A the correct answer choice.

Insulin/dextrose infusion will increase the activity of the sodium-potassium pump in the cells, which will in turn decrease serum potassium levels.

Nephrotic syndrome usually presents with the symptoms in this patient: low albumin, abnormal cholesterol, increased urinary albumin excretion, oedema, and as a consequence, hypertension as well.

Live virus vaccines include: Vaccinia (smallpox), Measles, Mumps, Rubella (MMR combined vaccine), Varicella (chickenpox), Influenza (nasal spray), Rotavirus, Zoster (shingles) and Yellow fever. Inactivated vaccines are Polio (IPV), Hepatitis A and Rabies.

Osteopenia is an early sign of bone weakening that is less severe than osteoporosis.
The numerical result of the bone density test is quantified as a T score. The lower the T score, the lower the bone density. T scores greater than -1.0 are considered normal and indicate healthy bone. T scores between -1.0 and -2.5 indicate osteopenia. T scores lower than -2.5 indicate osteoporosis.
DEXA also provides the patient’s Z-score, which reflects a value compared with that of person matched for age and sex.
Z-score values of –2.0 SD or lower are defined as below the expected range for age and those above –2.0 SD as within the expected range for age.