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Flashcards in General II Deck (49):
1

appendix mass vs abscess

Appendix massThe natural history of untreated acute appendicitis is that it will resolve, become gangrenous and perforate, or it will become surrounded by a mass of omentum and small bowel that walls off the inflammatory process and prevents inflammatory spread to the abdominal cavity yet delays resolution of the condition. Such patients usually present with a longer history (a week or more) of right lower quadrant abdominal pain. On examination the patient has a persistent low-grade fever, mild tachycardia and there is a tender indistinct mass in the right iliac fossa. The condition is usually best managed conservatively, as the risk of perforation has passed and removal of the appendix can be difficult. This differs from appendix abscess, when a perforated appendix becomes walled off by omentum. Unlike an appendix mass, the patient with an appendix abscess becomes systemically unwell with intermittent swinging pyrexia, rigors and profuse sweating. Drainage, either under radiological control or surgically, is the best initial treatment

2

Rectus sheath haematoma

Rectus sheath haematomaThis occurs following rupture of the inferior epigastric artery, typically after coughing or straining. The site of the haematoma is usually at the level of the arcuate line and produces a mass in the relevant iliac fossa. The lump is related to the muscles of the anterior abdominal wall, contraction of which makes the lump indistinct. Bruising may not always be apparent. The condition occurs in three distinct groups of individuals: elderly women, pregnant women and athletic, muscular men. Exploration of the anterior abdominal wall, evacuation of haematoma and ligation of the bleeding vessel may be required, however, small haematomas can be treated conservatively.

3

Utero-vaginal prolapse

Utero-vaginal prolapseUtero-vaginal prolapse is related to pelvic floor trauma sustained during childbirth and oestrogen deficiency following the menopause. Typically, symptoms associated with genital prolapse include a dragging sensation in the pelvis or awareness of ‘something coming down’. Resultant pelvic floor dysfunction impacts on urinary, sexual and rectal evacuatory function, resulting in voiding difficulties/urinary incontinence, impaired coitus and evacuation difficulties, respectively. The multi-system disruption of pelvic organ function suggests the diagnosis, which is confirmed on clinical examination. Such patients are prone to bladder and rectal prolapse as a result of weakening of the pelvic floor musculature. Treatment may include non-surgical measures (pelvic floor physiotherapy, oestrogen replacement therapy and intravaginal devices), although surgery to eliminate the prolapse and restore pelvic floor function offers definitive treatment.

4

Benign ovarian tumour

Benign ovarian tumourBenign ovarian tumours are common in this age group. Most tumours of the ovary are simply large versions of the cysts that form during the normal ovarian cycle, and so are small, asymptomatic and resolve spontaneously. These are termed ‘functional’ cysts. Benign germ cell tumours (eg dermoid cyst) are also common in women less than 30 years of age. Other histological types include benign epithelial and sex cord stromal tumours. Symptoms tend not to occur until the tumour is larger than 3–5 cm, although complications such as rupture, haemorrhage, or infection may result in acute pelvic pain. Occasionally, large tumours may give rise to urinary or gastrointestinal symptoms because of pressure effects. Menstrual disturbance is uncommon, unless the tumour secretes oestrogens (sex cord tumours). Cyst formation may complicate endometriosis (endometrioma), but here the clinical picture is usually of dysmenorrhoea, dyspareunia and sub-fertility.

5

Painful bladder syndrome

Painful bladder syndromePatients with painful bladder syndrome complain of bladder pain and irritative bladder symptoms (frequency, urgency, nocturia and dysuria). The bladder pain is worse when the bladder is distended, and often improved following micturition. Urine cultures are repeatedly negative, leading the unwary to exclude a urinary cause of pain in such patients. Causes include radiation, chemical and interstitial cystitis. Urine should be cultured for atypical organisms (Mycoplasma and Ureaplasma). Cystometry and cystoscopy are useful diagnostic tests and often reveal a low capacity, non-compliant (‘stiff’) bladder. Cystoscopy may reveal subepithelial haemorrhages in patients with interstitial cystitis and allows biopsies to be taken for histological confirmation of this condition.

6

caecal ca

Carcinoma of the caecumIn contrast with left-sided tumours, caecal carcinoma has an insidious onset with generalised features of malignant disease, such as anaemia, anorexia, weight loss and lethargy. Late features include a palpable mass in the right iliac fossa and obstruction to the ileocaecal valve resulting in small bowel obstruction. Obstruction of the appendiceal orifice can give rise to symptoms and signs of acute appendicitis, a fact that should be remembered when faced with a patient over the age of 40 with appendicitis.

7

pancreas ca

Carcinoma of the head of the pancreasThe history and findings are of obstructive jaundice with a palpable gallbladder. Courvoisier’s law states ‘when the gallbladder is palpable and the patient is jaundiced, the obstruction of the bile duct causing the jaundice is unlikely to be a stone because previous inflammation will have made the gallbladder thick and non-distensible’. While there are a few exceptions to this rule, the history of substantial weight loss, and of pain radiating to the left side of the back strongly indicate the likelihood of pancreatic carcinoma – which is the commonest cause of malignant biliary obstruction

8

mesenteric cyst

Mesenteric cystThese cysts are found most commonly in the mesentery of the ileum arising from congenitally misplaced lymphatic tissue (chylolymphatic cyst) or from remnants of reduplicated bowel (enterogenous cyst). They typically present in the second decade of life as a painless swelling or with recurrent episodes of abdominal pain. Acute abdominal pain may arise following rupture or bleeding into a cyst. On examination the characteristic finding is that of a fluctuant, resonant, spherical swelling, close to the umbilicus. The cyst is freely mobile in a plane at right angles to the root of the mesentery and may ‘slip’ during the course of the examination.

9

Congenital spherocytosis

Congenital spherocytosisApproximately 75% of cases are autosomal dominant disorders characterised by defects in the red cell membrane that render erythrocytes spheroidal, less deformable and vulnerable to splenic sequestration. Anaemia, moderate splenomegaly and jaundice are characteristic. After 10 years of age, 40–50% of patients develop gallstones secondary to hyperbilirubinaemia. Splenectomy is indicated in the majority of patients, as red cell survival reverts to normal even though the abnormality persists.

10

CML

B – Chronic myeloid leukaemiaThis primarily affects adults in the 4th and 5th decades of life, accounting for 15–20% of all cases of leukaemia. It is a clonal disorder of pluripotent stem cells that predominantly differentiate along the granulocytic pathway. Initial symptoms are non-specific; however, a dragging sensation in the abdomen caused by extreme splenomegaly is characteristic. Symptomatic hypersplenism may occur during the chronic phase of the disorder and may require splenectomy.

11

Overwhelming post-splenectomy sepsis

Overwhelming post-splenectomy sepsisAfter splenectomy the ability of the spleen to destroy encapsulated organisms is lost and infection can lead to the distinct clinical syndrome of overwhelming post-splenectomy infection (OPSI). In children splenectomised for trauma the incidence is about 1–2%, while for adults it is about 0.5%. Long-term penicillins are of proven value in children, as the maximal incidence of OPSI occurs within 2 years of surgery. Prophylaxis with polyvalent vaccines is also recommended (usually to pneumococcus, meningococcus and Haemophilus influenzae).

12

gallstone ileus

Gallstone ileusGallstones are responsible for less than 1% of all cases of small bowel obstruction. About 90% of stones entering the intestine will impact in the terminal ileum, although other reported sites include the duodenum, jejunum, colon and rectum. A stone formed in the gall bladder enters the small bowel via a biliary-enteric fistula, usually between the gallbladder and duodenum. Patients tend to be elderly and often do not report a history of cholecystitis. On X-ray the presence of a pneumobilia is pathognomic, provided there is no recent history of biliary-intestinal bypass or sphincterotomy

13

Volvulus

The case gives the classical history of a patient with a sigmoid volvulus who is typically elderly and institutionalised, suffering with chronic constipation and regular laxative use. There is usually a history of similar episodes in the past, which resolve following ‘untwisting of the sigmoid mesentery’. Typical X-ray findings are of a large oval gas shadow on the left hand side, which is looped onto itself, the so-called ‘bent inner tube’ or ‘coffee bean’ sign. Treatment is by decompression by means of a flatus tube inserted via a sigmoidoscope, done of course at arm’s length! Should this fail then operative ‘untwisting’ with or without resection may be required.

14

large bowel obstruction

There are four common causes of large bowel obstruction in Western society: carcinoma, diverticular disease, volvulus (principally sigmoid) and pseudo-obstruction.

15

Pseudo-obstruction

Pseudo-obstructionIn a large hospital, barely a week goes by without being referred such a patient either by the medical, neurosurgical, or orthopaedic teams. Colonic pseudo-obstruction probably represents about a quarter of all large bowel obstruction. It is a reactive dilatation and ileus, presumed (although notproven) to be secondary to disturbed autonomic (cholinergic) innervation. Classic conditions that may precipitate it are sepsis, especially chest infections, cerebrovascular accident/neurosurgery, fractured NOF, and spinal/retroperitoneal surgery (these probably directly disrupt nerves – indeed, the condition was first described in this respect with retroperitoneal tumours (Ogilvie’s syndrome).

16

ischaemic stricture

Ischaemic strictureIschaemia of the left hemicolon is a recognised complication of abdominal aortic aneurysm repair and occurs as a result of an insufficient collateral blood supply from the marginal artery following ligation of the inferior mesenteric artery. Presentation may be acute, with the passage of bloody diarrhoea, or insidious as in the case described. The region of the splenic flexure is commonly affected and chronic ischaemia may result in the formation of a stricture, indistinguishable from a carcinoma on barium enema examination. Mesenteric arteriography confirms the diagnosis.

17

Diffuse oesophageal spasm

Diffuse oesophageal spasmThis is a clinical syndrome characterised by symptoms of retrosternal chest pain and/or intermittent dysphagia. The chest pain can be severe and is frequently mistaken as cardiac in origin. Initially described by Osgood in 1889, the first manometric descriptions were not until 1958. Before manometry, the diagnosis relied on the symptom complex and the radiological findings of a normal oesophageal lumen, failure of peristaltic propagation, and simultaneous oesophageal contractions, sometimes resulting in a beaded appearance. A variety of radiological appearances and terminologies have been used such as ‘pseudodiverticulosis’, ‘segmental spasms’, and ‘corkscrew oesophagus’, although in most cases the diagnosis would be missed by barium swallow/gastroscopy as the oesophagus usually appears normal.

18

Bulbar palsy

This is a palsy of the tongue, muscles of mastication, muscles of deglutition, and facial muscles as a result of loss of function of brainstem motor nuclei. The signs are those of a lower motor neurone lesion. Bulbar palsy is one of the principal clinical patterns distinguished in motor neurone disease (MND) (25% of cases); other causes include Guillain–Barré syndrome, polio and brainstem tumours. MND never affects the extraocular movements, distinguishing it from myasthenia gravis. In contrast to bulbar palsy, pseudobulbar palsy is an upper motor neurone lesion usually caused by stroke.

19

actively bleeding duodenal ulcer with visible vessels at its base.

OGD and adrenaline injectionIn such a situation it is recommended that haemostasis is attempted with injection of 1 : 10, 000 adrenaline. Although evidence-based practice has shown heat probe, bipolar diathermy and injection sclerotherapy all to be effective, adrenaline injection is often used in combination with these modalities, and available trials show that adrenaline alone is equally effective. Repeated injection of fibrin glue or the application of micro-clips should be limited to specialist centres where operators are undertaking such procedures on a regular basis, and hence have special expertise. Only if this fails or if there are other endoscopic or clinical indications should the patient undergo surgery (under-running of ulcer).

20

pancreatic ca

Pancreatic carcinomaThe patient has presented with progressive symptoms suggestive of underlying pancreatic carcinoma. The finding of a palpable gallbladder may imply gallbladder pathology (eg gallstones). However, if Courvoisier’s law (‘if in the presence of jaundice the gallbladder is palpable, the cause is unlikely to be related to stones’) is applied, the correct diagnosis is reached. The principle is that if the obstruction of the common bile duct is a stone, the gallbladder is usually fibrotic and therefore does not distend. Cholangiocarcinoma and multiple liver metastases can present similarly but the former is much less common than pancreatic cancer (this is therefore the more likely diagnosis) and the latter is associated with a palpable liver not gallbladder. Other characteristic symptoms of pancreatic cancer include severe abdominal and back pain. Investigations include ultrasound, computed tomography and endoscopic retrograde cholangiopancreatography and cytology.

21

PBC

Primary biliary cirrhosisThe presentation described is fairly typical for this disorder, 90% of cases are female and the peak age is 45–50 years. This autoimmune disorder is suspected from the typical pattern of the liver function tests, is confirmed by the finding of anti-mitochondrial antibodies/smooth muscle antibodies, and is proven by characteristic histology from liver biopsy. Associated disorders include thyroid disease and CREST (calcinosis, Raynaud phenomenon, oesophageal motility disorders, sclerodactyly, telangiectasia) syndrome. Treatment is symptomatic, eg nutritional support for malabsorption. Liver transplantation may be required.

22

acute pancreatitis

Acute pancreatitisThe patient’s symptoms and signs are consistent with the diagnosis of acute pancreatitis. Of importance is the fact that a normal serum amylase concentration is not sufficiently sensitive to rule out the diagnosis. As in the case illustrated, late presentation makes this more likely; serum amylase typically peaks in the first 12–48 h and may return to normal after 72 h. In such cases the urinary amylase and serum lipase concentrations may be of value. Hypocalcaemia may occur in this potentially life-threatening disorder. The absence of previous episodes of pain, diabetes and symptoms suggestive of malabsorption make chronic pancreatitis unlikely. The diagnosis is confirmed on ultrasound and computed tomography scan findings.

23

Vipoma

VipomaThese tumours are of APUD cells of the gastroenteropancreatic endocrine system. Patients tend to be middle-aged, with more women affected than men. Episodes of profuse watery diarrhoea are typical and continue even in the presence of fasting. Hypokalaemia occurs following excessive gastrointestinal secretion and symptoms of such may be the presenting feature. Vasoactive intestinal peptide (VIP) normally inhibits acid secretion; therefore, patients are hypochlorhydric or achlorhydric. Other abnormalities include hypercalcaemia and hyperglycaemia. Plasma VIP levels are elevated. Initial treatment is directed toward correcting volume and electrolyte abnormalities. Octreotide controls diarrhoea in 80% of cases. Both computed tomography and magnetic resonance imaging are of value in diagnosis and staging. Surgical exploration with tumour resection leads to cure in 50% of patients

24

ß-cell tumour of the pancreas

ß-cell tumour of the pancreasß-Cell tumour, or insulinoma, is the commonest form of islet cell tumour. Symptoms are related to hypoglycaemia and occur with increasing frequency and severity. Attacks may be more frequent in the early hours of the morning, with vague abdominal pain relieved by carbohydrates, hence the confusion with peptic ulcer disease. Episodes may similarly occur following exercise. The diagnosis is suggested by Whipple’s triad, ie: • attacks occurring in the fasting state• during the height of the attack there is hypoglycaemia below 2.5 mmol/litre• symptoms relieved by glucose.Confirmation is by the identification of fasting hypoglycaemia associated with elevated levels of human insulin. Pancreatic angiography may aid in preoperative localisation with treatment by surgical excision of the tumour.

25

Gallstone ileus

Gallstone ileusThis patient has symptoms typical of small bowel obstruction. Small bowel obstruction from impaction of a gallstone in the distal ileum is rare but most commonly occurs in women over 70 years old. It accounts for 20% of older patients with small bowel obstruction who do not have a history of a hernia or previous abdominal surgery. Plain abdominal films may show a classic triad of small bowel obstruction, a gallstone in the gut and gas in the biliary tree (although the Editor has yet to observe this in practice). Treatment is surgical with proximal enterotomy, removal of the stone, a search for further stones but not cholecystectomy (which is dangerous and unnecessary). A bonus mark could be given for this question for also choosing Mirizzi’s syndrome because most patients also have a fistula

26

angiodysplasia

AngiodysplasiaThese are a type of arteriovenous malformation and are one of the common causes of significant lower gastrointestinal bleeding in the elderly population. As in this case, it is notoriously difficult to pinpoint the actual offending vessel. Where direct vision fails, mesenteric angiography or radionucleotide scans can sometimes be of diagnostic use but often also yield negative results if the vessel is not actively bleeding at the time of investigation. Should angiography demonstrate the source of bleeding, therapeutic embolisation can be performed. In cases of continued bleeding with negative investigations, treatment may involve total colectomy as a life-saving measure.

27

outlet obstruction

Outlet obstructionThis patient has ‘functional constipation’, because investigations have excluded an organic cause. Constipation may refer to the infrequent and/or difficult passage of stools. A predominance of symptoms of difficult evacuation, which is often referred to as obstructed defaecation (eg excessive straining, a sensation of incomplete evacuation, digitation etc) is suggestive of outlet obstruction, rather than slow transit constipation, although physiological confirmation is required as symptoms do not accurately predict underlying pathophysiology. The history of perineal massage and a ‘bulge’ in the vagina (posterior wall) is suggestive of the presence of a rectocoele, which may lead to outlet obstruction, as a result of redistribution of evacuatory forces during defaecation.

28

idiopathic megabowel

Persistent dilatation of the bowel is known as megabowel. This may occur secondary to an absence of ganglion cells in the myenteric plexus (Hirschsprung disease), where failure of relaxation of the affected segment leads to gross proximal dilatation. Alternatively, no obvious cause may be identifiable, when it is termed idiopathic megabowel. This condition is characterised by severe infrequency of defaecation, with several weeks between bowel movements. There is usually associated passive leakage of stool as a result of ‘overflow’ around impacted stool in the rectum. The diagnosis is confirmed on barium enema, which reveals dilatation of the rectum, and sometimes colon. Management involves behavioural, medical and, rarely, surgical treatment.

29

collagenous colitis

Collagenous colitisThis is an uncommon form of colitis and is part of the disease spectrum termed microscopic colitis (the other main subdivision is lymphocytic). It is most common among middle-aged women and there is an association with autoimmune disorders such as coeliac disease, thyroid disorders, diabetes and rheumatoid arthritis. Patients typically present with symptoms and signs of colitis, as in the case described. Stool and blood investigations tend to be normal. Endoscopic examination of the bowel similarly appears normal to the naked eye and the disorder is generally diagnosed on histolological examination of biopsies taken at endoscopy – hence the name, microscopic colitis. No cure is yet available. Treatment is directed at reducing inflammation and the symptoms of diarrhoea by means of drugs such as sulphasalazine and mesalazine. Short courses of steroids may be required for severe cases.

30

colorectal cancer risk

D – ColonoscopyWhen assessing a patient’s risk of developing colorectal cancer (CRC), the family history is of paramount importance. A family history of CRC in a first-degree relative is a significant finding and the age at which the diagnosis was made is similarly of importance when quantifying a patient’s overall relative risk. So an individual with a first-degree relative diagnosed with CRC earlier than age 55 years has a relative risk that is two- to fivefold above that of individuals without a family history of CRC. In this case, the patient is categorised as at moderate risk of developing CRC during her lifetime and as such this warrants screening by colonoscopy. Moderate risk is defined as having:
one first-degree relative affected by CRC before the age of 45 years
two (one aged less than 55 years) or three relatives at any age affected by CRC or endometrial carcinoma who are first-degree relatives of each other and one a first-degree relative of the patient
two affected first-degree relatives (one aged less than 55 years).

31

faecal incontinence

The aetiology of faecal incontinence should be thought of as a disturbance to the passage or passenger. The ‘passage’ consists of the rectum, which stores and expels faeces when appropriate, and the anal canal which is composed of two rings of muscle (the internal and external anal sphincter) that relax to allow emptying. The pudenal nerve is a mixed nerve that provides motor function to the external anal sphincter, as well as sensation to the anal canal providing sensory input that forms part of a ‘sampling reflex’. The ‘passenger’ or faeces, if loose, will frequently result in incontinence even in the presence of a normally functioning anorectal sphincteric complex (as anyone who has experienced severe dysentery would know). Alternatively, sphincteric disruption may lead to incontinence even for normal stool

32

rectal fistulas

Transsphincteric fistulae have a primary tract that passes through both sphincters at varying levels into the ischiorectal fossa where they may lead to ischiorectal abscess formation. The fistula may be described as high, mid- or low depending on where the fistula crosses the external sphincter, ie above, at, or below the level of the dentate line respectively.

IntersphinctericSepsis having developed within the intersphincteric plane, it follows the path of least resistance down the intersphincteric space, emerging at the peri-anal skin, resulting in an intersphincteric fistula (and often presenting acutely as a peri-anal abscess

ExtrasphinctericThese rare fistulae run without relation to the sphincters and are classified according to their pathology. They often originate from a segment of sigmoid diverticular disease or from ileal or sigmoid Crohn’s disease. They can also be created by injudicious probing of peri-anal sepsis (iatrogenic).

33

anal cancer

Anal Carcinoma, (B - Anal intra-epithelial neoplasia, or E - Condylomata acuminata) Infection with human papillomavirus can lead to anal warts and dysplastic changes within the anal epithelium (mild to severe: termed anal epithelial neoplasia). These may progress to anal carcinoma. So patients with warts and those with other sexually transmitted diseases affecting the anus should have biopsies and possibly thence surveillance if required.

34

fibroadenoma

FibroadenomaThis young woman has clinical, histological and radiological signs of a fibroadenoma (sometimes called a ‘breast mouse’ on account of its mobility). Fibroadenoma is a benign breast disorder and is a developmental aberration of lobular development. Any organ in the body that undergoes cyclical changes of proliferation and regression can be subject to disorders of these processes. To appropriately reflect this the nomenclature of benign breast disease refers to the processes as ‘aberrations of normal development and involution’ or ANDI (described by the Cardiff Breast Clinic). The umbrella of ANDI covers cyclical mastalgia and nodularity, cyst formation, sclerosing adenosis, duct ectasia, fibroadenoma and papilloma formation. Surgical excision should be offered in women over 35, or if the lump is over 4 cm in size. In the under 35s excision or reassessment should be proffered dependent on patient wishes (anxiety etc). Cancer risk in a fibroadenoma is 1/1000 (usually lobular carcinoma in situ).

35

breast cyst

Breast cystCysts usually present as discrete, painful swellings, often with sudden onset. Cysts fall into the category of ANDI (see above) as they represent aberrations of lobular involution. They are commonly seen in perimenopausal women, and can be multiple and involve both breasts. Fineneedle aspiration of a cyst reveals fluid that can be green, yellow, or brown in colour. If the fluid is blood-stained and, after aspiration, a mass remains at the site of the swelling, malignancy must be suspected. In such cases the fluid should be sent for cytology and a mammogram should be performed

36

invasive ductal ca

F – Invasive ductal carcinomaThe clinical presentation clearly points to a diagnosis of breast cancer. The cytological grading, C5 (malignant cells) confirms this. The features of this lump that make it more likely to be a ductal carcinoma rather than a lobular one are:
presence of a single lesion (multiple and bilateral lesions are more likely in lobular cancer)
branching microcalcification visible on mammography
increased incidence of ductal carcinoma versus lobular (75–80% of cases versus 10–15% of cases respectively).

37

The length of this is the actual length of myosin.

A-band
The A-band actually reflects the length of the myosin fibres in muscle fibres.

38

The distance between two Z-lines.

Sarcomere
A sarcomere is the distance between two Z-lines. This distance changes with species, but changes very little from person to person.

39

This decreases during contraction.

H-band
Under the microscope, it is the H-band (and also the I-band) that decrease (shortens) during contraction. The myosin of the A-band and the actin in the I-band increase their overlap as the Z lines move closer together.

40

Smooth muscle cells

Unlike skeletal and cardiac muscle, smooth muscle cells do not have striated appearance.

They do however still contain both actin and myosin.

Smooth muscle cells have intrinsic contractile properties the activity of which is controlled by the autonomic nervous system.

Smooth muscle and cardiac muscle cells are electrically coupled.

41

Epithelial dysplasia features

Epithelial dysplasia is associated with nuclear hyperplasia and hyperchromatism, prominent nucleoli, increased nuclear to cytoplasmic ratio, increased cell density, increase mitotic activity with abnormal mitoses. An intact basement membrane would be a feature of normality but also would be in keeping with dysplasia rather than signifying infiltration and cancer.

42

Subacute cord degeneration

Subacute cord degeneration is caused by B12 deficiency and typically presents with weakness and tingling affecting all limbs.

A disc protrusion typically produces pain affecting the nerve roots irritated locally.

Central cord syndrome typically causes weakness affecting all limbs and is usually associated with a fall in which there is hyperextension of the neck.

Multiple sclerosis tends not to present with neurology affecting all limbs and usually presents in younger patients.

43

HIV infections

Cryptococcal meningitis is the most common cause of fungal brain disease.

Co-trimoxazole is the treatment of choice for Pneumocystis jirovecii pneumonia (PCP). It is also used as a prophylaxis agent in HIV patients at risk from PCP.

Opportunistic infections normally occur with a CD4 count less than 200 cells/mm3.

It is debatable whether patients with a CD4+ count of <500 should be treated with antiretrovirals. The cut off is stated as less than 200 in most texts. However, recent studies now suggest that long term outcome is improved with treatment at much higher CD4+ counts.

Up to 25% of patients can have a normal appearance initially.

44

Features of atrial fibrillation (AF) include which of the following?

Discordant apical and radial rate

AF is the commonest rhythm disturbance, and is associated with a discordance between apical and radial rate, an irregularly irregular pulse rate and, of course, AV dissociation, as not all the atrial impulses are conducted.

Radio femoral delay is associated with coarctation, and pulsus paradoxus with conditions such as severe asthma or pericardial effusion.

Water hammer pulse is associated with increased stroke volume of the left ventricle and decrease in the peripheral resistance, leading to the widened pulse pressure of aortic regurgitation.

45

A 30-year-old male is admitted to the MAU with a 72 hour history of significant lethargy, fever and a sore throat.
The nurse is concerned that his breathing is 'noisy' and describes it to you over the phone as harsh and high pitched. His current observations demonstrate a temperature of 39.4 and a raised respiratory and heart rate.
What is the most likely diagnosis?

Added airway sounds must always be addressed with the utmost urgency.

Stridor in particular is heard predominantly on inspiration and implies a compromised upper airway. It is important to remember that stridor is a sign and not a diagnosis, and the underlying cause must be sought urgently. All the causes listed above can present with stridor, thus the history is paramount in helping to identify the correct precipitant.

In children croup (viral laryngotracheitis) is the most common reason for a patient to present with stridor, with parainfluenza 1 virus being the most common precipitant. The barking cough of croup and subsequent stridor is predominantly limited to children under the age of 12, and thus stridor in adults should demand the clinician to pursue other more likely diagnoses.

In this case the patient appears toxic with worsening lethargy, pyrexia and overt deterioration of the upper airway. A bacterial cause must be suspected and bacterial tracheitis is the most likely culprit. Diphtheria can present with stridor, however immunisation programmes have reduced the incidence in the western world. Remember to consider varying levels of immunisation in patients who have grown up abroad.

Laryngospasm is a common cause of stridor in adults but again a relevant precipitant must be sought out. Exposure to smoke and toxic fumes in a history should lend a high degree of suspicion, and prompt the clinician urgently to involve the anaesthetic teams in consideration of securing the patient's airway.

The diagnoses of foreign body and anaphylaxis are both life threatening and must always be considered and excluded, however the duration and onset of the stridor will be a key factor. An abrupt onset with a history of eating nuts or even chewing on a pen lid or plastic bead is often present in foreign body aspiration and thus must be sought out.

Anaphylaxis again may have a defined food precipitant and the onset is often more rapid than in the other conditions.

46

You are the foundation year doctor in the Emergency department when a mother brings her 2-year-old son to you with a one hour history of noisy breathing.
She states that although he had a mild coryza over the last week, he was improving and so they had gone to a children's picnic with nursery friends. Another parent had found him coughing and spluttering, and ever since the breathing has remained noisy.
He is an ex-prem baby born at 30 weeks, but has attained all his milestones to date and is fully immunised.
Though he appears well in the department, his current observations demonstrate a raised respiratory rate and saturations of 91% on air.
What is the most likely diagnosis?

Added airway sounds must always be addressed with the utmost urgency.

In children stridor can be heard on both inspiration and expiration depending on the anatomical level of the pathology, but in all cases implies a compromised upper airway. It is important to emphasis that stridor is a sign and not a diagnosis, and the underlying cause must be sought urgently. As all the causes listed above can present with stridor, thus the history is paramount in helping to identify the correct precipitant.

This scenario is the classic case presentation of foreign body aspiration, in which an inquisitive child, usually aged 1 to 3 years, has put an object into their mouth and inhaled it. The foreign body is now lodged within the trachea or main bronchi and obstructs airflow causing the stridor. The concern is that the airway may fully obstruct depending upon the position and lead to respiratory deterioration.

The nature of onset is always abrupt and may be highlighted by a choking or vomiting episode. All cases must be referred to specialists for consideration of bronchoscopy and removal of foreign body.

Anaphylaxis can also have an abrupt onset, however a more definitive precipitant such as a new food may be implicated.

In children croup (viral laryngotracheitis) is the most common reason for a patient to present with stridor, with parainfluenza 1 virus being the most common precipitant. The classic 'barking cough' of croup and subsequent stridor is predominantly limited to children under the age of 12.

Risk stratification can be done in these children by performing a Westley croup score to classify patients as mild, moderate or severe and to allow initiation of treatment appropriately. In this scenario, croup is a possibility however other diagnoses are more probable.

Epiglottitis has now become rare in children, as the previous main precipitant of Haemophilus influenzae B is now routinely immunised against.

Laryngomalacia is associated with premature babies and in the early weeks can present with stridor however with increasing age the larynx matures and stridor should settle. ENT teams will follow these patients closely and the stridor history from the parents will be a chronic one.

47

A 19-year-old woman presents with gross oedema and frothy urine. She is investigated and is found to have an albumin of 10 and heavy proteinuria of 11.5 g/l with a cholesterol of 9 mmol/l.
She undergoes a renal biopsy and is diagnosed as having minimal change nephropathy. She initially goes into remission with oral prednisolone but on withdrawal of steroids relapses quickly. She is readmitted with a painful left leg and further significant oedema.
D-dimers are elevated and a deep vein thrombosis extending to her external iliac vein is diagnosed on Doppler ultrasound.
She is commenced on heparin but symptoms fail to respond. She is back on oral prednisolone and diuretics. Her albumin remains at 20. On examination she has gross oedema of both legs and some mild facial swelling. Her left leg is painful and erythematous with a dusky hue. JVP is not raised. Her BP lying is 110/70 mmHg and standing is 102/62 mmHg.
Her clotting studies show an APTT ratio of 1.86 and INR of 1.5.
What is the most likely diagnosis?

ATIII deficiency is likely, as nephrotics often lose antithrombin in the urine.

Hodgkin's disease can cause minimal change disease, but there is nothing in the history to suggest this.

She has no postural drop, so dehydration is unlikely in the presence of oedema.

Anti-phospholipid syndrome does not cause minimal change nephropathy.

48

WHO pain ladder

Morphine and other opiod drugs cause constipation. They should always be prescribed with laxatives as a preventative measure.

Analgesia should follow the WHO guidelines (1996), steps 1 to 3. Although it has been proven that bone pain usually can be settled with a combination of nonsteroidal anti-inflammatory drugs (NSAIDs)(step 1), and weak opiods (step 2), the treatment for stage 3 is morphine/oxycodone (moderate to severe pain).

When prescribing pain killers you should always try and follow the analgesic ladder, where if a drug is not providing satisfactory pain relief, a stronger drug should be used instead.

SVC obstruction is best treated with radiotherapy; also nerve compression from bony metastasis can be treated with radiotherapy.

Hyoscine may be used to help dry secretions in lung cancer as it acts as an antimuscarinic. Hyoscine butylbromide causes less sedation than hyoscine hydrobromide. Both are given by subcutaneous infusions (see BNF section on palliative care)

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A 53-year-old woman with inoperable cancer has pain due to posterior abdominal wall infiltration. This has been controlled well with Kapake (codeine 30 mg and paracetamol 500 mg), two tablets four times per day.
The patient has been admitted with nausea and vomiting the cause of which is, as yet, unknown. Because she cannot retain her analgesics, she has severe pain in her loin.
What is the best option for controlling her pain until the vomiting settles?

This patient has inoperable carcinoma and already needs opiate analgesia orally; as she is vomiting she will need parenteral analgesia.

The most effective way of achieving this, and being able effectively to titrate the dose to achieve adequate analgesia, is subcutaneous diamorphine by continuous infusion.

Fentanyl patches are difficult to titrate because they are used for 72 hours. You usually therefore only use them once a patient has a stable opiate usage.

Intramuscular pethidine has a delayed onset and its effect is prolonged, which again is not ideal when you do not know what the patient's opiate requirements are.

Oral morphine is unlikely to be tolerated whilst she is vomiting.

Non-steroidals are unlikely to be sufficient in this case.