This is a classical picture of graft versus host disease (GVHD) following bone marrow transplant. Acute GVHD occurs in the first 100 days post transplant with chronic GVHD occurring 100-300 days after transplant. GVHD is graded according to the Seattle system, and each organ involved is scored (skin, liver, and gut).

The standard initial treatment in the acute setting is high-dose methylprednisolone started immediately. If there is no response, a more intensive immunosuppressive agent such as alemtuzumab or antilymphocyte globulin is needed.

Normally blood glucose is filtered out by the kidneys, however as glucose levels exceed 180 mg/dL, the renal tubules become saturated and additional reabsorption is not possible. Glucose remains in the renal tubules, causing additional water and electrolytes to diffuse into the renal system and be excreted as urine (also known as osmotic diuresis). Excessive urine production results in electrolyte loss, and dehydration. Thus an important part of managing these patients is fluid replacement. Initially a litre of 0.9% NaCl over the 1st hour is given which may followed by either 0.45 or 0.9% NaCl, depending on the corrected serum sodium and the hemodynamic status of the patient.

Patients with diabetes often develop ophthalmic complications, the most common and potentially most blinding of these complications is diabetic retinopathy.
The following are the 5 stages in the progression of diabetic retinopathy:
1. Dilation of the retinal venules and formation of retinal capillary microaneurysms.
2. Increased vascular permeability.
3. Vascular occlusion and retinal ischemia.
4. Proliferation of new blood vessels on the surface of the retina.
5. Vitreous haemorrhage and contraction of the fibrovascular proliferation.
The first 2 stages of diabetic retinopathy are known as background or nonproliferative retinopathy. Initially, the retinal venules dilate, then microaneurysms (tiny red dots on the retina that cause no visual impairment) appear. As the microaneurysms or retinal capillaries become more permeable, hard exudates appear, reflecting the leakage of plasma.

Mild nonproliferative diabetic retinopathy (NPDR) or background diabetic retinopathy is indicated by the presence of at least 1 microaneurysm, while neovascularization is the hallmark of Proliferative Diabetic Retinopathy (PDR).

The history is suggestive of hypertrophic obstructive cardiac myopathy. The degree of left ventricular hypertrophy is strongly associated with sudden cardiac death.

Deletion of part of chromosome 5 or 7 is a poor prognostic feature for acute myeloid leukaemia (AML).

AML is the acute expansion of the myeloid stem line, which may occur as a primary disease or follow the secondary transformation of a myeloproliferative disorder. It is more common over the age of 45 and is characterized by signs and symptoms largely related to bone marrow failure such as anaemia (pallor, lethargy), frequent infections due to neutropenia (although the total leucocyte count may be very high), thrombocytopaenia (bleeding), ostealgia, and splenomegaly.

The disease has poor prognosis if:
1. Age of the patient >60 years
2. >20% blasts seen after the first course of chemotherapy
3. Chromosomal aberration with deletion of part of chromosome 5 or 7.

Acute promyelocytic leukaemia (APL) is an aggressive form of AML.

During pregnancy, profound changes in thyroid physiology occur to provide sufficient thyroid hormone (TH) to both the mother and foetus. This is particularly important during early pregnancy because the fetal thyroid starts to produce considerable amounts of TH only from approximately 20 weeks of gestation, until which time the foetus heavily depends on the maternal supply of TH. This supply of TH to the foetus, as well as increased concentrations of TH binding proteins (thyroxine-binding globulin) and degradation of TH by placental type 3 iodothyronine deiodinase, necessitate an increased production of maternal TH. This requires an intact thyroid gland and adequate availability of dietary iodine and is in part mediated by the pregnancy hormone human chorionic gonadotropin, which is a weak agonist of the thyroid-stimulating hormone (TSH) receptor. As a consequence, serum-free thyroxine (FT4) concentrations increase and TSH concentrations decrease from approximately the eighth week throughout the first half of pregnancy, resulting in different reference intervals for TSH and FT4 compared to the non-pregnant state.

The causes of orthostatic hypotension include the following: Hypovolemia (a drop in the volume of blood) and dehydration (low fluid volume in the body). Common causes of these are bleeding, elevated sugar, diarrhoea, vomiting, and medications like thiazide diuretics (HCTZ) and loop diuretics (furosemide, bumetanide)

Lesions in cerebellum and pontine region should be excluded. So the most appropriate investigation is MRI of cerebellum.

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.

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.

Gastric carcinoma may present as atypical general symptoms including emesis, fatigue and weight loss. It may also result in anaemia which might be responsible for the palpitations. The left supraclavicular swelling is referring to Virchow’s node, strongly associated with gastric cancer. Ascites and hepatomegaly generally appear late in the course of the disease and Blood group A has been shown to be associated with gastric cancer.

Because of the patient’s history of chronic analgesic use of daily paracetamol intake, the most likely diagnosis of this case is Analgesic misuse headache. In these cases, the headache is only temporarily relieved by analgesics. Treatment involves gradual withdrawal of analgesics.

Distal renal tubular acidosis is due to defective proton secretion from the alpha intercalated cells of the distal tubule caused by dysfunction of the H+/K+ antiporter on the apical membrane. This leads to failure of H+ excretion thereby causing systemic acidosis and potassium depletion. Inability to lower the urine pH below 5.3 in the presence of systemic acidosis is the diagnostic hallmark of type I or distal renal tubular acidosis. Hypercalciuria, hypocitraturia and elevated urinary pH observed in distal renal tubular acidosis can lead to nephrocalcinosis and may cause renal calculi, obstructive uropathy and renal failure necessitating surgical or endoscopic stone extraction.

Extrinsic allergic alveolitis (EAA) refers to a group of lung diseases that can develop after exposure to certain substances. The name describes the origin and the nature of these diseases:

‘extrinsic’ – caused by something originating outside the body
‘allergic’ – an abnormally increased (hypersensitive) body reaction to a common substance
‘alveolitis’ – inflammation in the small air sacs of the lungs (alveoli)

Symptoms can include: fever, cough, worsening breathlessness and weight loss. The diagnosis of the disease is based on a history of symptoms after exposure to the allergen and a range of clinical tests which usually includes: X-rays or CT scans, lung function and blood tests.

EAA is not a ‘new’ occupational respiratory disease and occupational causes include bacteria, fungi, animal proteins, plants and chemicals.

Examples of EAA include:

Farmer’s lung
This is probably the most common occupational form of EAA and is the outcome of an allergic response to a group of microbes, which form mould on vegetable matter in storage. During the handling of mouldy straw, hay or grain, particularly in a confined space such as a poorly ventilated building, inhalation of spores and other antigenic material is very likely.

There also appears to be a clear relationship between water content of crops, heating (through mould production) and microbial growth, and this would apply to various crops and vegetable matter, with the spores produced likely to cause EAA.

Farmer’s lung can be prevented by drying crops adequately before storage and by ensuring good ventilation during storage. Respiratory protection should also be worn by farm workers when handling stored crops, particularly if they have been stored damp or are likely to be mouldy.

CD8+ T cells recognize antigens in the form of short peptide fragments bound to major histocompatibility complex class I (MHCI) molecules on the target cell surface.1 Specific engagement of peptide-MHCI (pMHCI) complexes via the clonotypically expressed ?β T-cell receptor (TCR) triggers a range of effector functions that play a critical role in protective immunity against intracellular infections and various malignancies.

Difficulty in breathing and unequal chest movements are due to paralysis of the diaphragm. So the nerve affected is the left phrenic nerve.

The patient has primary Hypogonadism.
Since he already had two children, Klinefelter syndrome is excluded and the patient does not need karyotyping.
His lab results are normal indicating normal pituitary gland functions.
So the next step is testicular ultrasound as testicular tumour, infiltration or idiopathic failure is suspected.

Etanercept is a TNF receptor fused with human immunoglobulin. It binds to TNF-alpha preventing it from binding to its normal receptor. Thus, inhibiting it competitively. It is used for treatment of rheumatoid arthritis in adults when traditional treatments fail. When injected subcutaneously, it is accompanied with skin reactions and urticaria. It should be given intravenously. Serious blood disorders and demyelination have also been associated.

Extrinsic allergic alveolitis, also known as hypersensitivity pneumonitis, is an allergic response of the lungs to an environmental allergen. Nodular shadowing in the chest X-ray is characteristic of extrinsic allergic alveolitis.
Churg-Strauss syndrome is an auto-immune disorder that is known to cause vasculitis mostly in patients having a pre-existing airway disease.
Cryptogenic organizing pneumonia is an inflammatory condition of the alveoli. The CXR of which shows ground-glass opacifications.
The CXR of progressive massive fibrosis also shows opacifications normally in the upper lung lobes.

Bradycardia and miosis should be anticipated following the administration of anticholinesterases.

Anticholinesterase agents include the following medications:
– Pyridostigmine, neostigmine, and edrophonium which play a significant role in the diagnosis and the management of myasthenia gravis.
– Rivastigmine, galantamine and donepezil are cholinesterase inhibitors found to be significantly useful in the management of Alzheimer’s disease.

Mechanism of action and pharmacological effects:
Inhibition of cholinesterase increases the level and the duration of action of acetylcholine within the synaptic cleft.

Thus, cholinergic effects such as a reduction in heart rate (bradycardia), miosis (pupillary constriction), increased secretions, increased gastrointestinal motility and reduction in BP may occur with anticholinesterases.

Toxins such as organophosphates and carbamates also are primarily anticholinergic and cause the following typical SLUDGE symptoms:
– Salivation
– Lacrimation
– Urination
– Diaphoresis
– Gastrointestinal upset
– Emesis