MRCP OFFICIAL PAPER 2 Flashcards
Treatment for erythrodermic psoriasis?
Erythroderma is a term used when more than 95% of the skin is involved in a rash of any kind.
‘red man syndrome’
Initial treatment is with topical white soft paraffin smeared all over the skin, which helps to make the skin more comfortable, partially reduces the inflammation, improves the skin barrier, thus helping to prevent entry of bacteria through the skin (), and helps to reduce water loss from the skin (and prevent dehydration).
Which protein is abnormal in Marfan’s syndrome?
Marfan’s syndrome is an autosomal dominant connective tissue disorder. It is caused by a defect in the FBN1 gene on chromosome 15 that codes for the protein fibrillin-1.
At laparotomy, bowel was found to be ischaemic from the lower part of the duodenum through to midway along the transverse colon.
What artery is most likely to be occluded?
Superior Mesenteric Artery.
The superior mesenteric arises from the abdominal aorta and supplies the small intestine from the distal duodenum as well as the large intestine as far as 2/3 of the transverse colon.
Erythematous, scaly rash involving the nasolabial folds and eyebrows, and the skin overlying the sternum. There was mild scaling of the scalp. The nails were normal.
What is the most likely diagnosis?
Seborrhoeic dermatitis
Mx for fungal nail infections?
onychomycosis
if limited involvement - topical treatment with amorolfine 5%
if more extensive involvement due to a dermatophyte infection: oral terbinafine is currently recommended first-line; 6 weeks - 3 months therapy is needed for fingernail infections whilst toenails should be treated for 3 - 6 months
With which condition is H. pylori infection most strongly associated?
Duodenal ulcers
Duodenal ulcers have a strong association with Helicobacter pylori, with over 90% of patients with duodenal ulcers being H. pylori positive. There is also an association with gastric ulceration and carcinoma but to a lesser degree.
GORD is not particularly associated with H. pylori since infection tends to reduce gastric acid secretion.
Pulse abnormality seen in cardiac tamponade?
Pulsus paradoxus
What additional information would be most useful to support a diagnosis of syndrome of inappropriate antidiuretic hormone?
Thyroid function tests.
SIADH is a diagnosis made once other causes of hyponatraemia are ruled out such as hypocortisolaemia, thyroid dysfunction (hypothyroidism) and adequate renal function.
What receptors are chiefly involved in mediating the antipsychotic effects of risperidone?
The primary mechanism of action of antipsychotic drugs is dopamine receptor antagonism.
A 68-year-old woman with atrial fibrillation presented for DC cardioversion. The procedure resulted in successful restoration of sinus rhythm.
Which drug would be most likely to maintain sinus rhythm following this procedure?
Amiodarone.
Ix for Addison’s disease?
In a patient with suspected Addison’s disease the definite investigation is an ACTH stimulation test (short Synacthen test). Plasma cortisol is measured before and 30 minutes after giving Synacthen 250ug IM.
A 32-year-old man presented with weight loss and feeling generally unwell. On direct questioning, he had been having dizzy spells, especially on sudden changes in posture.
On examination, he was tanned. There was a postural drop in his BP.
What is the most likely biochemical finding?
Plasma adrenocorticotropic hormone 95 pmol/L (3.3–15.4)
The clinical picture is compatible with primary adrenal failure. In a young person, Addison’s disease is the most likely cause. The adrenocorticotropic hormone (ACTH) will be raised in the absence of negative feedback due to cortisol deficiency.
- hyperkalaemia
- hyponatraemia
- hypoglycaemia
- metabolic acidosis
MOA of isosorbide mononitrates?
Increased cyclic guanosine monophosphate (GMP) production
A 25-year-old man presented with a 5-day history of foul-smelling diarrhoea, abdominal pain, nausea, bloating and flatulence. He had returned from a holiday in Borneo 1 week previously.
On examination, he appeared dehydrated. Examination was otherwise normal.
Stool microscopy: trophozoite and cysts
Giardia intestinalis.
the history of small bowel malabsorptive symptoms and of travel to an endemic area is suggestive of giardiasis. This is confirmed by the finding of trophozoites and cysts on microscopy.
Mx: Metronidazole
Which antibiotics cause prolonged QT?
Antimicrobials that cause QT prolongation are:
- Erythromycin, Clarithromycin
- Moxifloxacin
- Fluconazole and Ketoconazole.
Which coagulation factor is most likely to be present at a reduced activity in patient taking Warfarin?
Warfarin inhibits the vitamin K-dependent synthesis of clotting factors including factor II, VII, IX and X as well as the regulatory factors protein C and protein S.
Blood abnormality seen in osteomalacia?
- Low vitamin D levels
- Low calcium
- Low Phosphate
- Raised alkaline phosphatase
Mx: Vitamin D supplementation (Colecalciferol)
A 55-year-old woman presented with a 2-month history of lower back pain, for which she had been taking paracetamol 4 g daily. She admitted to drinking 16 units of alcohol per week.
serum alanine aminotransferase 55 U/L (5–35)
serum aspartate aminotransferase 29 U/L (1–31)
serum alkaline phosphatase 90 U/L (45–105)
serum IgG 21.0 g/L (6.0–13.0)
serum IgA 2.4 g/L (0.8–3.0)
serum IgM 1.8 g/L (0.4–2.5)
What is the most likely cause of her abnormal liver function tests?
Autoimmune hepatitis.
The raised IgG levels suggests autoimmune hepatitis and a diagnosis can be provisionally made while awaiting the autoantibody profile.
The ratio of alanine aminotransferase (ALT) to aspartate aminotransferase (AST) is greater than 1, which favours autoimmune or viral over alcoholic cause.
Artery occluded in posterior MI?
Posterior descending artery.
It is the left circumflex artery that supplies the posterior descending artery in around 15% of people, called a left dominant system.
In 85% of people, the posterior descending artery arises from the right coronary artery, called a right dominant system.
What investigation is most appropriate for assessing response to Hep C antiviral medication?
HCV Viral Load.
Guidance for monitoring response to treatment of hepatitis C is by finding a sustained virological response using HCV viral load.
A 67-year-old woman presented with palpitations and a goitre. Propranolol was started to improve her symptoms.
On examination, she had a coarse tremor and sweaty palms, but no thyroid eye signs.
Low TSH
Raised T4
technetium-99m scan of thyroid: increased uptake in right upper lobe, with uptake suppressed in rest of thyroid gland.
What is the most appropriate treatment for her thyroid condition?
Radioiodine.
This case highlights the treatment of an autonomous nodule causing hyperthyroidism (‘toxic adenoma’). The technetium-99m scan highlights the focus of overactivity and does not suggest thyroiditis, therefore prednisolone is not required. The lack of eye signs is further reassurance.
Total thyroidectomy is not an appropriate treatment option given the localisation of the increased activity to the right upper lobe. While carbimazole and propylthiouracil may be an interim treatment, the overactivity would still continue if the medication was stopped and therefore the more appropriate (and definitive) treatment is radioiodine.
A 37-year-old woman presented with a 1-day history of abdominal pain and diarrhoea.
On examination, she was drowsy and hallucinating, and had widespread purpura.
Investigations:
haemoglobin 92 g/L (115–165)
white cell count 13.3 × 109/L (4.0–11.0)
platelet count 17 × 109/L (150–400)
serum creatinine 195 µmol/L (60–110)
What abnormality is most likely to be present on blood film examination?
Fragmented cells.
The patient presents with gastrointestinal and neurological symptoms, and the blood results show anaemia, thrombocytopaenia and renal impairment. The neurological features and marked thrombocytopaenia would be in keeping with thrombotic thrombocytopaenic purpura (TTP). Both TTP and HUS are associated with microangiopathic haemolytic anaemia (MAHA). An important blood film feature of MAHA is the presence of fragmented red cells.
Formula for calculating serum osmolality?
Calculated osmolality = (2 × Na) + (2 × K) + glucose + urea (all in mmol/L).
As potassium is present and concentration is higher than 5 mmol/L, accounting for this and associated anions should be made by using the formula including potassium multiplied by 2.
Organism seen in lyme disease as well as rash?
Lyme disease is caused by the spirochaete Borrelia burgdorferi and is spread by ticks.
Erythema migrans: ‘Bulls-eye’ rash is typically at the site of the tick bite.
Headache, fever, lethargy, heart block.
dont forget can develop LMN FACIAL PALSY.
- Doxycycline if early disease. 2. Amoxicillin is an alternative if doxycycline is contraindicated (e.g. pregnancy)
People with erythema migrans should be commenced on antibiotic without the need for further tests.
