Hypogammaglobulinemia is a complication of chronic lymphocytic leukaemia (CLL) that leads to recurrent infections.

CLL is a type of cancer caused by monoclonal proliferation of well-differentiated lymphocytes, typically B cells (99%). Onset of the disease is usually asymptomatic and later constitutes anorexia, weight loss, bleeding, and recurrent infections. Lymphadenopathy is more marked in CLL than in chronic myelogenous leukaemia (CML).

Investigations to diagnose CLL include blood film and immunophenotyping. Smudge cells (also known as smear cells) seen on the blood film point towards CLL. Complications of the disease include hypogammaglobulinemia leading to recurrent infections, autoimmune haemolytic anaemia in 10–15% of the patients, and transformation to high-grade lymphoma (Richter’s transformation).

Thioridazine has a quinidine-like action on the heart and is known to cause cardiac arrhythmias including prolonged PR and QT intervals and widening of QRS complexes. Intravenous magnesium sulphate is regarded as the treatment of choice for this arrhythmia.

Normal pO2 but decreased oxygen saturation is characteristic of methemoglobinemia.

Methemoglobinemia is a rare condition in which the haemoglobin iron is in oxidized or ferric state (Fe3+) and cannot reversibly bind oxygen. Normally, the conversion of ferrous form of iron (Fe2+) to its ferric form (Fe3+) is regulated by NADH methaemoglobin reductase, which results in the reduction of methaemoglobin to haemoglobin. Disruption in the enzyme leads to increased methaemoglobin in the blood. There is tissue hypoxia as Fe3+ cannot bind oxygen, and hence the oxygen-haemoglobin dissociation curve is shifted to the left.

Methemoglobinemia can occur due to congenital or acquired causes. Congenital causes include haemoglobin variants such as HbM and HbH, and deficiency of NADH methaemoglobin reductase. Acquired causes are drugs (e.g. sulphonamides, nitrates, dapsone, sodium nitroprusside, and primaquine) and chemicals (such as aniline dyes).

The features of methemoglobinemia are cyanosis, dyspnoea, anxiety, headache, severe acidosis, arrhythmias, seizures, and loss of consciousness. Patients have normal pO2 but oxygen saturation is decreased. Moreover, presence of chocolate-brown coloured arterial blood (colour does not change with addition of O2) and brown urine also point towards the diagnosis of methemoglobinemia.

The pattern of muscle involvement seen with quadriceps and long-finger flexors is characteristic of inclusion body myositis, an inflammatory myopathy. Polymyositis is likely to cause a predominantly proximal weakness, associated with muscle pain. The signs and symptoms are not consistent with upper cord compression, as there would likely be sensory signs, reflex changes, and possible urinary symptoms. Motor neuron disease cannot be ruled out, but there are no findings of upper motor neuron or bulbar features.

Historically, high rates of maternal and fetal death have been reported for pregnant women with pulmonary hypertension (30–56% and 11–28%, respectively). The causes of poor maternal outcomes are varied and include risk of death from right heart failure and stroke from intracardiac shunting. Furthermore, there is a high peri-/post-partum risk due to haemodynamic stress, bleeding complications and the use of general anaesthesia, which can all lead to right heart failure.
The most common risk to the foetus is death, with premature birth and growth retardation being reported in successfully delivered children.
CXR is not contraindicated in pregnancy. D-dimers are not used as a diagnostic aid as they are almost always elevated in pregnancy. Nifedipine, although contraindicated in pregnant women may be used judiciously if the need arises.

From the given history the patient has NYHA grade III heart failure. He can be safely started on an ACE inhibitor as his serum potassium was towards the lower limit. As there an impairment of renal function, his urea, creatinine and serum electrolytes should be closely monitored after commencing an ACE inhibitor. Adding atenolol will not have any clinical benefit. Increasing the digoxin dose is not needed as the patient is in sinus rhythm. Increasing furosemide will only have symptomatic relief.

SIGN produced guidelines in 2008 on the management of migraines. Key points include that if patients have migraines with aura then the combined oral contraceptive (COC) is absolutely contraindicated due to an increased risk of stroke (relative risk 8.72).

People with polyarteritis nodosa often exhibit anaemia of chronic disease. Leucocytosis and eosinophilia may also be present. ANCA is only rarely positive. As polyarteritis nodosa affects the kidneys as well, the creatinine is elevated in most cases.

In mild-to-moderate heroin overdoses, arterial blood gas (ABG) analysis reveals respiratory acidosis. In more severe overdoses, tissue hypoxia is common, leading to mixed respiratory and metabolic acidosis.

The normal range for PaCO2 is 35-45 mmHg (4.67 to 5.99 kPa). Respiratory acidosis can be acute or chronic. In acute respiratory acidosis, the PaCO2 is elevated above the upper limit of the reference range (i.e., >45 mm Hg) with an accompanying academia (i.e., pH < 7.35). In chronic respiratory acidosis, the PaCO2 is elevated above the upper limit of the reference range, with a normal or near-normal pH secondary to renal compensation and an elevated serum bicarbonate levels (i.e., >30 mEq/L).

Arterial blood gases with pH = 7.31; pCO2 = 7.4 kPa; pO2 = 8.1 kPa would indicate respiratory acidosis.

To describe how often a disease or another health event occurs in a population, different measures of disease frequency can be used. The prevalence reflects the number of existing cases of a disease. In contrast to the prevalence, the incidence reflects the number of new cases of disease and can be reported as a risk or as an incidence rate. Prevalence and incidence are used for different purposes and to answer different research questions.

Poor prognostic factors for breast cancer include:
1. Young age (<40 years)
2. Premenopausal at the time of diagnosis
3. Increased tumour size
4. High-grade tumour
5. Oestrogen and progesterone receptor-negative tumour
6. Positive lymph node status

Nail dystrophy (pitting of nails, onycholysis, subungual hyperkeratosis), dactylitis, sausage shaped fingers are most commonly seen with psoriatic arthropathy. There is asymmetric joint involvement most commonly distal interphalangeal joints. Uveitis and sacroiliitis may also occur. Arthritis mutilans may occur but is very rare. Cutaneous lesions may or may not develop. When they do, its usually much after the symptoms of arthritis.

This clinical scenario describes pernicious anaemia. Anti-intrinsic factor (IF) antibodies are most specific for pernicious anaemia. Antigastric parietal cell antibodies have a higher sensitivity but are less specific for pernicious anaemia. The other antibodies listed are not related to pernicious anaemia. Anti-TTG is seen with Celiac’s disease, anti-TPO is seen with thyroid disease, GAD is seen with type I diabetes, but this does not explain her anaemia.

The question describes an alcohol abusing man with chronic epigastric discomfort, radiating into his back, worse with meals, and foul-smelling stools, weight loss, as well as chronic nausea. This is likely, thus chronic pancreatitis due to alcohol abuse. Hepatomegaly and peripheral neuropathy secondary to anaemia support the diagnosis of long term alcohol abuse. Bacterial overgrowth may present with diarrhoea and is a less likely diagnosis than pancreatitis. Celiac disease is a less likely diagnosis than pancreatitis, and you would also expect mention of diarrhoea. VIPoma would also likely present with diarrhoea. Cecal carcinoma would more than likely present with blood in the stool.

Traditionally two forms of macular degeneration are seen:
– Dry (geographic atrophy) macular degeneration is characterized by drusen – yellow round spots in Bruch’s membrane.
– Wet (exudative, neovascular) macular degeneration is characterized by choroidal neovascularization. Leakage of serous fluid and blood can subsequently result in a rapid loss of vision. This carries the worst prognosis.

The most probable diagnosis in the given scenario would be Charles-Bonnet syndrome.

Charles-Bonnet syndrome (CBS) is characterized by persistent or recurrent complex hallucinations (usually visual or auditory), occurring in clear consciousness. This is generally against a background of visual impairment (although visual impairment is not mandatory for a diagnosis). Insight is usually preserved. This must occur in the absence of any other significant neuropsychiatric disturbance.

Risk factors include:
Advanced age
Peripheral visual impairment
Social isolation
Sensory deprivation
Early cognitive impairment

CBS is equally distributed between sexes and does not show any familial predisposition. The most common ophthalmological conditions associated with this syndrome are age-related macular degeneration, followed by glaucoma and cataract.

Well-formed complex visual hallucinations are thought to occur in 10-30 percent of individuals with severe visual impairment. The prevalence of CBS in visually impaired people is thought to be between 11 and 15 percent.

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.

Normal distribution, also known as the Gaussian distribution, is a probability distribution that is symmetric about the mean. The normal distribution has the following properties:
– It is symmetric around the mode, the median and the mean of the distribution.
– It is unimodal
– The area under the curve and over the x-axis is unity (i.e. equal to one).
– Its density has two inflection points.
– Its density is log-concave.
The standard deviation (SD) is a measure of how much dispersion exists from the mean. SD = square root (variance)

Clubbing of the fingers can be present in many clinical conditions like CLD, bronchiectasis, lung abscess, Ulcerative colitis and Crohn’s Disease. Koilonychia or spoon shaped nails are a typical finding in iron deficiency anaemia. Splinter haemorrhages are pin point haemorrhages found in infective endocarditis and secondary to trauma. Yellow nails are present in pulmonary and renal diseases.

This patient presentation is unlikely to be an L5 nerve root lesion given the results of the MRI scan. Therefore, the most likely diagnosis is a mononeuritis affecting the left common peroneal nerve. This would lead to sensory loss over the dorsum of the foot and anterolateral leg on the left.

Charcot arthropathy is a progressive condition of the musculoskeletal system that is characterized by joint dislocations, pathologic fractures, and debilitating deformities. It results in progressive destruction of bone and soft tissues at weight-bearing joints. In its most severe form, it may cause significant disruption of the bony architecture.
Charcot arthropathy can occur at any joint; however, it occurs most commonly in the lower extremity, at the foot and ankle. Diabetes is now considered to be the most common aetiology of Charcot arthropathy.

The number needed to treat (NNT) is valuable information in treatment decisions. NNT is the inverse of the absolute risk reduction (1/ARR) between two treatment options. Control event rate = 10 / 50 = 0.2
Experimental event rate = 18 / 120 = 0.15

Absolute risk reduction = 0.2 – 0.15 = 0.05
Number needed to treat = 1 / 0.05 = 20

NPV = TN / FN+TN

= TN (true negative) / FN+TN (false negative + true negative)

= Probability (patient not having disease when test is negative)

Charles Bonnet syndrome (CBS) involves visual hallucinations due to eye disease, usually associated with a sharp decline in vision. The phenomenon is seen in patients with moderate or severe visual impairment. It can occur spontaneously as the vision declines or it may be precipitated, in predisposed individuals, by concurrent illness such as infections elsewhere in the body.

It is not clear why CBS develops or why some individuals appear to be predisposed to it. It is particularly noted in patients with advanced macular degeneration. It has been suggested that reduced or absent stimulation of the visual system leads to increased excitability of the visual cortex (deafferentation hypothesis). This release phenomenon is compared to phantom limb symptoms after amputation.

CBS is much more common in older patients because conditions causing marked visual loss are more common in older people. However, it can occur at any age and has been described in children.
The prevalence is hard to assess due to considerable under-reporting, perhaps because patients frequently fear that it is a sign of mental illness or dementia. However, it is thought to occur in:
About 10-15% of patients with moderate visual loss.
Possibly up to 50% of people with severe visual loss.
Presentation:
The nature of the hallucination depends on the part of the brain that is activated. The hallucinations may be black and white or in colour. They may involve grids/brickwork/lattice patterns but are typically much more complex:

The hallucinations are always outside the body.
The hallucinations are purely visual – other senses are not involved.
The hallucinations have no personal meaning to the patient.
Hallucinations may last seconds, minutes or hours.
CBS tends to occur in a ‘state of quiet restfulness’. This may be after a meal or when listening to the radio (but not when dozing off).
Symptoms also have a tendency to occur in dim lighting conditions.
Patients may report high levels of distress, with some patients reporting anger, anxiety and even fear associated with the hallucinations.

The burning sensation described is typical of a neuropathy affecting the small unmyelinated and thinly myelinated nerve fibres. General neurological examination and reflexes are usually normal in this type of neuropathy unless there is coexisting large (myelinated) fibre involvement. Neuropathy affecting the large myelinated sensory fibres generally causes glove and stocking sensory loss and loss of reflexes.

A precordial thumb is not routinely recommended because of its very low success rate for cardioversion of a shockable rhythm. It’s only recommended when there is a delay in getting the defibrillator.

Acute cord compression is a medical emergency. Typically, signs of segmental damage at the level of compression are usually combined with corticospinal tract dysfunction (e.g., hyperreflexia, Babinski’s sign and weakness) and sensory deficits below the level of compression. Symptoms include spinal pain that precedes the development of weak legs and sensory loss. There may be loss of bladder (and anal) sphincter control, manifesting as hesitancy, frequency and, finally, painless retention.
Spinal X-rays are rarely diagnostic. MRI is usually the investigation of choice and should not be delayed, but if not available consider doing a CT scan and myelography to confirm cord compression and fully define the level and extent of the lesion. If malignancy is the cause, it is important to give dexamethasone (oral or intravenous) while considering therapy more specific to the cause.

The patient most likely suffers from Paget’s disease of the bone as his radiological examination shows both osteolytic and osteosclerotic lesions. Any bone or bones can be affected, but Paget’s disease occurs most frequently in the pelvis > lumbar spine > femur > thoracic spine > sacrum > skull > tibia.

Pulmonary metastasis is seen in 20-54% of extrathoracic malignancies. The lungs are the second most frequent site of metastases from extrathoracic malignancies. Twenty percent of metastatic disease is isolated to the lungs. The development of pulmonary metastases in patients with known malignancies indicates disseminated disease and places the patient in stage IV in TNM (tumour, node, metastasis) staging systems.
Chest radiography (CXR) is the initial imaging modality used in the detection of suspected pulmonary metastasis in patients with known malignancies. Chest CT scanning without contrast is more sensitive than CXR.
Breast, colorectal, lung, kidney, head and neck, and uterus cancers are the most common primary tumours with lung metastasis at autopsy. Choriocarcinoma, osteosarcoma, testicular tumours, malignant melanoma, Ewing sarcoma, and thyroid cancer frequently metastasize to lung, but the frequency of these tumours is low.

Only cystine stones are semi-opaque because they contain sulphur. All the other stones will appear either radio-lucent or radio-opaque.