Quiz Questions Flashcards
A 45 year old woman from Jamaica presents with a 6 month history of weight loss and a two week history of fever. On examination she had cervical lymphadenopathy. Her calcium was raised at 3.0 and CXR showed bilateral hilar lymphadenopathy.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
H. Sarcoidosis - Sarcoidosis is a chronic multisystem disease with an unknown aetiology. Lymphadenopathy is a common presentation and nodes are enlarged but non-tender, typically involving the cervical and submandibular nodes. Although uncommon, the patient may present with unexplained modest weight loss (which is often mistaken for TB or lymphoma along with the abnormal CXR) and a low-grade fever. CXR will typically show bilateral hilar lymphadenopathy and CXR findings are used in the staging of disease. Additionally, serum calcium and ACE levels may be raised. A transbronchial biopsy is essential for diagnosis in most cases and shows the presence of non-caseating granulomas. Black people have a higher lifetime risk of sarcoidosis, as do those of Scandinavian origin. The mainstay of treatment for severe disease involves systemic corticosteroids. Skin manifestations include erythema nodosum which are tender erythematous nodules and lupus pernio presenting with indurated plaques with discoloration on the face.
A 25 year old man with a 3 day history of high temperatures, aching limbs and neck discomfort. Apart from temperatures of 39 degrees C and some mild conjunctivitis, examination was normal. Antibiotics were prescribed but had no effect.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
J. Influenza - This is an acute respiratory tract infection caused by seasonal viral influenza A or B, hence antibiotics would have no effect. It is characterised by respiratory symptoms including rhinorrhoea, cough, fever, chills, headache and myalgia. Recent upper respiratory tract infection has led to associated viral conjuncitivitis. The examination in this case is of course otherwise unremarkable. Antigenic change presents a challenge in creating new vaccines as there is no incremental protection from previous vaccinations. There have been 4 pandemics since 1918, the recent one being ‘swine flu’ in April 2009, caused by new gene rearrangement of human, avian and swine influenza.
A 50 year woman normally resident in the UK returned from visiting relatives in Pakistan. She described intermittent fevers with rigors, diarrhoea and severe headaches. She is mildly jaundiced.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
E. Malaria - In the Western world, almost all cases of malaria occurs in travellers so an adequate travel history is crucial or the diagnosis may be missed. Patients typically present with non-specific symptoms such as a fever, sweats, chills and myalgia. This can also include the diarrhoea which this patient is experiencing and headaches. The jaundice here suggests falciparum infection, which is always the cause in severe disease. This woman has just returned from an endemic area. Sometimes EMQs will describe patterns of fevers occuring at regular intervals of 48-72 hours associated with P. vivax, P. ovale and P. malariae infections but in most patients there is no specific pattern. Hepatosplenomegaly is a common presenting sign although not common at presentation in a first world setting. Thrombocytopenia is common with falciparum infection and a mild degree of anaemia ais commonly seen. WCC can be high, low or normal.
The severity of malaria depends partly on the species and also on host immunity. Therefore those who live in endemic areas may develop minimal symptoms due to IgG antibody and cell-mediated immunity and physiological tolerance of parasitaemia. Pregnant women affected by P. falciparum are also susceptible to the complications of pregnancy due to placental parasite sequestration. Treatment of malaria in pregnancy must be managed with an ID specialist and should be treated with IV antimalarial therapy.
The test of choice is Giesma-stained thick and thin blood smears. Thick films sensitively detect parasites whereas thin films allow species identification and calculation of parasitaemia to guide treatment. Studies have shown that for P falciparum, the most effective treatment is artesunate which is more effective than quinine without the risk of cinchonism. Numerous studies such as the AQUAMAT study in The Lancet showing that quinine should no longer be the established treatment of choice.
A 22 year old man presented with a two week history of fever and drenching night sweats. He had experienced severe itching during this time. Examination was normal except for swollen supraclavicular lymph nodes. CXR showed a mediastinal mass.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
L. Hodgkins Lymphoma - This is a case of lymphoma. Reed-Sternberg cells are binucleate cells characteristically seen in Hodgkin’s lymphoma. Hodgkin’s is localised to a single group of nodes (normally the cervical and/or supraclavicular) and extranodal involvement is rare. Mediastinal involvement is common. Spread is contiguous and B symptoms may be present such as a low grade fever, weight loss and night sweats. Pruritis may be found in approximately 10% of cases but has no prognostic significance. 50% of cases is associated with EBV infection and distribution is bimodal with peaks in young and old. There is classically pain in lymph nodes on alcohol consumption.
A 35 year old pregnant woman developed a temperature with chills and increased urinary frequency. She is tender in the right loin and has vomited. Dipstick urinalysis is positive for leukocytes, nitrites and blood.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
N. Pyelonephritis - Acute onset fever with chills, flank pain, vomiting and positive urine dipstick all point to the diagnosis of acute pyelonephritis. Urinalysis is highly sensitive but not very specific. Pregnancy is a risk factor for complicated disease as the enlarging uterus compresses the ureters and hormonal changes increase the likelihood of obstructive uropathy. In uncomplicated pyelonephritis, the most common cause is E. coli and gram stain will typically reveal gram negative rods, either E. coli, Proteus or Klebsiella. Gram positive cocci that could be implicated include enterococci and staphylococci. Older patients can often also present non-specifically. Treatment should start before culture results are received to prevent the patient from deteriorating, with empirical antibiotics.
A 50 year old woman presented with a temperature and aching joints 2 days prior to departure on holiday to Egypt. On examination she had a tender swelling on her left upper arm.
A. Post immunisation B. Glandular fever C. Pneumonia D. HIV infection E. Malaria F. Drug reaction G. SLE H. Sarcoidosis I. Appendicitis J. Influenza K. Tuberculosis L. Hodgkin's lympoma M. Gastric carcinoma N. Pyelonephritis
A. Post immunisation - Travel to Egypt may necessitate vaccinations for diseases such as typhoid and HAV. This is a side-effect of the vaccine and the history here points towards this. Vaccine side effects tend to be uncommon although this depends on the specific vaccine given. For example, some 10-30% of people will experience mild side effects such as muscle pain and headache after being given the yellow fever vaccine.
A 40 year old man returned from India 4 days ago & came down with fever. He went to his GP & got some paracetamol. His fever persisted, & he had a few bouts of diarrhoea & cough. He started getting drowsy & was admitted from casualty where his blood culture was taken. The next day the lab reported Gram negative bacilli seen on blood culture.
A. Mycobacterium tuberculosis B. Legionella pneumophila C. Dengue virus D. Falciparum malaria E. Lassa fever F. Entomoeba histolytica G. Streptococcus pneumoniae H. Salmonella typhi I. Neisseria meningitidis type B J. Influenza
H. Salmonella typhi - Typhoid (or enteric fever) is a faecal-oral illness caused by Salmonella enterica, serotype S typhi, Salmonella enterica and S paratyphi. There are over 2500 serovars for S enterica. In this country, it is mainly from people who have returned from a country where it is endemic – India, for example, which has the highest incidence of this disease. Mexico should also ring alarm bells. The water supplies are not treated and sanitary conditions are dire which prompts transmission of this infection. Humans are the only known reservoir. The vaccine only offers moderate protection and does not protect against paratyphoid infection. This person has a high fever which is a hallmark of infection (sometimes in a step-wise manner) which is not responding to paracetamol (it persists) and blood culture (you need a big sample of blood for testing as count is usually low) shows a gram negative bacilli, and he has returned from an endemic region. The fever of typhoid classically increases incrementally until a persistent fever with temperature 39-41 is established. There are also typically flu like symptoms after onset of fever and cough. Remember that characteristic findings such as bradycardia and rose spots may not be present and indeed rose spots may not be easy to spot in those with dark skin. Rose spots are blanching red lesions reported in 5-30% of cases usually occuring on the chest or abdomen.
This patient needs antibiotics though the temperature will fall over about week. A third generation cephalosporin is indicated due to resistance to fluoroquinolones in the Indian sub-continent. If the sensitivity panel returns and shows that this organism is sensitive to all antibiotics then ciprofloxacin should be given.
50 year old man went for Hajj. He was vaccinated against hepatitis & Group C meningococci. He came back with a high fever & was admitted with neck stiffness & drowsiness. He had a lumbar puncture & blood cultures. Gram stain of cerebrospinal fluid showed Gram negative diplococci.
A. Mycobacterium tuberculosis B. Legionella pneumophila C. Dengue virus D. Falciparum malaria E. Lassa fever F. Entomoeba histolytica G. Streptococcus pneumoniae H. Salmonella typhi I. Neisseria meningitidis type B J. Influenza
I. Neisseria meningitidis type B - This patient has meningitis. A big risk factor is crowding which occurs during Hajj. Commonly there will be a headache, fever and nuchal rigidity. There may also be an altered mental status, confusion, photophobia and vomiting. Kernig’s sign is uncommon but is positive when attempts to extend the leg are met with resistance when the patient is supine with the thigh flexed to 90 degrees. Another uncommon sign is Brudzinski’s sign and a petechial/purpuric rash, typically associated with meningococcal meningitis.
CT head should be considered before LP if there is any evidence of raised ICP. A LP will confirm the diagnosis with bacterial meningitis showing a low CSF glucose, elevated CSF protein and positive CSF culture/gram stain or meningococcal antigen. The CSF gram stain showing a gram negative diplococci here gives the organism away. If you know your gram stains etc you can get this one from just reading the last line.
40 year old social worker, lived in India & the Far East for the last 2 years. He came back with an intermittent fever of 2 months duration. On examination the GP noted tenderness & swelling of the right hypochondrium. He was sent to the hospital where on ultrasound a liver abscess was found.
A. Mycobacterium tuberculosis B. Legionella pneumophila C. Dengue virus D. Falciparum malaria E. Lassa fever F. Entomoeba histolytica G. Streptococcus pneumoniae H. Salmonella typhi I. Neisseria meningitidis type B J. Influenza
F. Entomoeba histolytica - This is amoebiasis caused by E. Histolytica. Again, there is history of travel to an endemic area. Additional risk factors include being male and male-male sex, both oral and anal. Diagnosis would be confirmed by the detection of antigen in stool samples, serology or PCR. As neither of these methods are 100% sensitive, it is normally good to use more than 1 test in diagnosis. The presentation is normally with diarrhoea, without blood or mucus, present for several days or longer, indicating intestinal infection. Half also report weight loss. This patient, has however got the fever more associated with hepatic infection. There may also be jaundice here and hepatomegaly on examination. The RUQ tenderness found here is indicative of hepatic infection and the mass here is likely a hepatic abscess, which itself may extend into the pleural or pericardial cavities in rare cases, causing effusions. Splenic abscesses and even brain abscesses with neurological abnormalities can also rarely occur. Treatment is with nitroimidazoles followed by agents like paromomycin.
30 year old stone mason came from India to work on a temple being constructed. He presented to the GP with history of fever, night sweats & cough of 3 months duration. Chest x-ray showed a cavitating shadow.
A. Mycobacterium tuberculosis B. Legionella pneumophila C. Dengue virus D. Falciparum malaria E. Lassa fever F. Entomoeba histolytica G. Streptococcus pneumoniae H. Salmonella typhi I. Neisseria meningitidis type B J. Influenza
A. Mycobacterium tuberculosis - It is important to have a high level of suspicion when evaluating patients with risk factors who present with suggestive symptoms. Night sweats, fever, malaise, cough, haemoptysis and erythema nodosum are all suggestive. In the first half of the 20th century, tuberculosis accounted for over 90% of cases of erythema nodosum. Other key risk factors for pulmonary TB include exposure to infection and returning from or being born in a high-risk region such as Asia, Africa and Latin America. If TB is suspected, the patient should be placed in isolation and a CXR obtained with 3 sputum samples cultured for AFB being the gold standard of diagnosis. Cavitating lesions like the one this patient has can be seen on CXR but is non-specific for TB. Culture takes several weeks so sputum smears will be done before culture results are known. Interferon-gamma release assays (IGRAs) are now used by some hospitals to rapidly determine a patient’s TB status. All patients who have TB should be tested for HIV within 2 months of diagnosis.
A 22-year-old student went to Thailand on holiday. A week following his return, he presented to his GP with a flu like illness and high fever. His GP presumed it was flu and told him to go home. Two days later, he re-presented to A&E, this time vomiting.
A. Mycobacterium tuberculosis B. Legionella pneumophila C. Dengue virus D. Falciparum malaria E. Lassa fever F. Entomoeba histolytica G. Streptococcus pneumoniae H. Salmonella typhi I. Neisseria meningitidis type B J. Influenza
D. Falciparum malaria - In the Western world, almost all cases of malaria occurs in travellers so an adequate travel history is crucial or the diagnosis may be missed. Patients typically present with non-specific symptoms such as a fever, sweats, chills and myalgia. This student has just returned from an endemic area. Sometimes EMQs will describe patterns of fevers occuring at regular intervals of 48-72 hours associated with P. vivax, P. ovale and P. malariae infections but in most patients there is no specific pattern. Hepatosplenomegaly is a common presenting sign although not common at presentation in a first world setting. Thrombocytopenia is common with falciparum infection and a mild degree of anaemia are commonly seen. WCC can be high, low or normal.
Pregnant women affected by P. falciparum are susceptible to the complications of pregnancy due to placental parasite sequestration. Treatment of malaria in pregnancy must be managed with an ID specialist and should be treated with IV antimalarial therapy.
A 22 year old female medical student returned from elective in Nigeria 3 months ago, she has had a fever & night sweats for 3 weeks.
choose the SINGLE investigation, most likely to confirm the diagnosis, from the above list of options:
A. Abdominal ultrasound B. Echocardiogram C. Urine microscopy & culture D. Thick blood film E. Liver function tests F. Lumbar puncture G. IVP H. Blood cultures I. Full blood count J. Clinical exam only K. CT brain scan L. Chest x-ray & sputum cultures M. Throat swabs
D. Thick blood film - In the Western world, almost all cases of malaria occurs in travellers so an adequate travel history is crucial or the diagnosis may be missed. Patients typically present with non-specific symptoms such as a fever, sweats, chills and myalgia. This medical student has just returned from an endemic area. Sometimes EMQs will describe patterns of fevers occuring at regular intervals of 48-72 hours associated with P. vivax, P. ovale and P. malariae infections but in most patients there is no specific pattern.
The test of choice is Giesma-stained thick and thin blood smears. Thick films sensitively detect parasites whereas thin films allow species identification and calculation of parasitaemia to guide treatment. Studies have shown that for P falciparum, the most effective treatment is artesunate which is more effective than quinine without the risk of cinchonism. However, not all hospitals are currently licensed to use it in the UK (in London, only the Hospital for Tropical Diseases and Northwick Park). Artesunate is manufactured by a pharmaceutical company in China and there are doubts over the quality of the product. However, there have now been numerous studies such as the AQUAMAT study in The Lancet showing that quinine should no longer be the established treatment of choice.
A 23 year old man has been living rough in London since being made homeless 6 months ago. He presents in A&E, unwell with 1 month history of cough, weight loss, fever & night sweats. Choose the SINGLE investigation, most likely to confirm the diagnosis, from the above list of options:
A. Abdominal ultrasound B. Echocardiogram C. Urine microscopy & culture D. Thick blood film E. Liver function tests F. Lumbar puncture G. IVP H. Blood cultures I. Full blood count J. Clinical exam only K. CT brain scan L. Chest x-ray & sputum cultures M. Throat swabs
L. Chest x-ray & sputum cultures - The patient’s symptoms point towards pulmonary TB. CXR is the first line test to order. Classically, in primary disease there are middle and lower zone infiltrates. Post-primary TB usually involves apical changes with or without cavitation. However, recent students have indicated that both presentations are seen in both primary and post-primary TB. HIV positive patients tend to have a more atypical CXR including effusion, lower zone involvement and a miliary pattern. Sputum cultures on LJ medium are the most sensitive and specific test but growth on solid media can take 4-8 weeks. A smear will be done in the meantime to look for AFB but the sensitivity is lower than that of a culture.
An 18 year old student started university 3 months ago. She has felt flu-like for 2 days. In the last 2 hours she has developed a severe headache, vomiting, temp of 390C & photophobia. On examination she has neck stiffness & a positive Kernig’s sign. Choose the SINGLE investigation, most likely to confirm the diagnosis, from the above list of options:
A. Abdominal ultrasound B. Echocardiogram C. Urine microscopy & culture D. Thick blood film E. Liver function tests F. Lumbar puncture G. IVP H. Blood cultures I. Full blood count J. Clinical exam only K. CT brain scan L. Chest x-ray & sputum cultures M. Throat swabs
F. Lumbar puncture - This patient has meningitis. Universities are common sites of outbreaks due to crowding. Commonly there will be a headache, fever and nuchal rigidity. There may also be an altered mental status, confusion, photophobia and vomiting. Kernig’s sign is uncommon but is positive when attempts to extend the leg are met with resistance when the patient is supine with the thigh flexed to 90 degrees. Another uncommon sign is Brudzinski’s sign and a petechial/purpuric rash, typically associated with meningococcal meningitis.
CT head should be considered before LP if there is any evidence of raised ICP. A LP will confirm the diagnosis with bacterial meningitis showing a low CSF glucose, elevated CSF protein and positive CSF culture/gram stain or meningococcal antigen.
5 days after a bowel resection for cancer, a 70 year old man gets a swinging fever & becomes confused. Choose the SINGLE investigation, most likely to confirm the diagnosis, from the above list of options:
A. Abdominal ultrasound B. Echocardiogram C. Urine microscopy & culture D. Thick blood film E. Liver function tests F. Lumbar puncture G. IVP H. Blood cultures I. Full blood count J. Clinical exam only K. CT brain scan L. Chest x-ray & sputum cultures M. Throat swabs
H. Blood cultures - Post-surgical patients are at risk of developing an abscess. An abscess is a collection of pus or infected material. A swinging fever is strongly indicative of an abscess and a blood culture is required to identify the pathogenic organism. Percutaneous or surgical drainage will usually be required with appropriate antimicrobial therapy.
A 3 year old girl is febrile and has been unwell for 12 hours. She complains of a headache and is drowsy but otherwise neurologically intact. Choose the single most discriminating investigation in the acute management from the list of options:
A. ESR B. Blood cultures C. Chest X-ray D. Urine culture E. Stool electron microscopy F. EEG G. Stool culture H. Culture of joint aspirate I. C-reactive protein J. Lumbar puncture K. Throat swab L. Full blood count M. CT brain
J. Lumbar puncture - Meningitis commonly affects the extremes of age (60 years) due to impaired immunity in the former, and waning immunity in the latter. A lumbar puncture to obtain CSF is the most important investigation when this diagnosis is considered. This should not however delay the starting of empirical antimicrobial therapy. When the specific organism is identified, treatment can be modified accordingly. Fever, headache and drowsiness should make you suspicious here of this diagnosis. Atypical presentations can also occur, and these tend to happen in the very young, older or immunocompromised patients. In older patients, frequently, the only presenting sign of meningitis is confusion or an altered mental status. In infants, the signs and symptoms can be very non-specific and may include lethargy, poor feeding, irritability and fever. A rash is noted in 80-90% of patients, commonly 4-18 hours after initial symptoms and is associated with meningococcal aetiology (although may be present with any bacterial meningitis).
In bacterial meningitis, the CSF pressure is usually raised and WBC count is elevated. The glucose level is decreased compared to the serum value and the protein level is increased. In those who are untreated, Gram stain and culture of CSF are usually positive for the causative organism. However, in those who get antibiotics before cultures are obtained, the diagnostic yield is much lower (as low as 20%). If a lumbar puncture is delayed or regarded as clinically unsafe (for instance, raised intracranial pressure), then blood samples should be obtained for culture. Of course, a head CT should be considered before LP if there is focal neurology, new onset seizures, papilloedema, altered consciousness or any sign which may indicate raised ICP.
A 2 month old child has had a fever and cough for three days. He is tachypnoeic with grunting and has nasal flaring. Choose the single most discriminating investigation in the acute management from the list of options:
A. ESR B. Blood cultures C. Chest X-ray D. Urine culture E. Stool electron microscopy F. EEG G. Stool culture H. Culture of joint aspirate I. C-reactive protein J. Lumbar puncture K. Throat swab L. Full blood count M. CT brain
C. Chest X-ray - This 2 month old child has pneumonia and is displaying signs of respiratory distress (tachypnoea, nasal flaring, grunting). The most sensitive and specific test to perform is a CXR (PA and lateral). What may be seen is an infiltrate, consolidation, effusions and cavitation. Initial treatment is empirical with antibiotics (amoxicillin is the first choice in children).
A 3 year old has had a high fever and sore throat for 2 days. This evening he had a generalised convulsion lasting 2 minutes. He is now drowsy but rousable with no localising signs. Choose the single most discriminating investigation in the acute management from the list of options:
A. ESR B. Blood cultures C. Chest X-ray D. Urine culture E. Stool electron microscopy F. EEG G. Stool culture H. Culture of joint aspirate I. C-reactive protein J. Lumbar puncture K. Throat swab L. Full blood count M. CT brain
K. Throat swab - This child has septicaemia secondary to a throat infection caused by group A beta-haemolytic streptococcus (Streptococcus pyogenes). This is no additional reason to believe that this is toxic shock syndrome or rheumatic fever, but the sore throat and fever for 2 weeks requires a culture of a throat swab to look for the causative organism. This is the most specific and sensitive test for GAS. However, a rapid antigen test can also be done for GAS which is about 80% sensitive and 95% specific compared to a throat culture but obviously much quicker. Blood cultures can also be done as the infection is now systemic but the throat culture is the best choice here as this is the obvious initial source of the infection. Treatment is with antibiotics and may be with penicillin or amoxicillin. GAS resistance to macrolides has been reported. Supportive care in this patient is also essential.
An 8 year old has developed a painful, swollen knee over the last day. O/E there is a tender, warm effusion of the left knee. She also has a pyrexia of 38 degrees. Choose the single most discriminating investigation in the acute management from the list of options:
A. ESR B. Blood cultures C. Chest X-ray D. Urine culture E. Stool electron microscopy F. EEG G. Stool culture H. Culture of joint aspirate I. C-reactive protein J. Lumbar puncture K. Throat swab L. Full blood count M. CT brain
H. Culture of joint aspirate - This 8 year old has septic arthritis. The septic knee joint here will be painful, hot, swollen and restricted movement of the affected joint. In all cases of suspected joint sepsis, the joint needs to be aspirated and empirical antibiotics need to be commenced once appropriate cultures have been taken. If the cause is a low virulence organism, TB or if in an older patient, the joint is prosthetic, then the presentation may be more insidious in onset. If there is already underlying joint disease then a septic joint should be suspected if the symptoms are out of proportion to normal disease activity. Some 20% of cases of septic arthritis is polyarticular. In sexually active patients, gonococcal arthritis is an important differential to consider. Presence or absence of fever is not a reliable indicator of joint sepsis and the diagnosis is largely one of clinical suspicion – treatment should therefore be commenced on this basis regardless of blood test results or microbiology. Synovial fluid Gram stain and culture is however positive in 70% of cases.
A 12 month old boy has a 24 hour history of profuse diarrhoea and irritability. He has a low grade fever. Choose the single most discriminating investigation in the acute management from the list of options:
A. ESR B. Blood cultures C. Chest X-ray D. Urine culture E. Stool electron microscopy F. EEG G. Stool culture H. Culture of joint aspirate I. C-reactive protein J. Lumbar puncture K. Throat swab L. Full blood count M. CT brain
G. Stool culture - The best investigation for presumed infectious diarrhoea here is to do a stool culture. It is not an absolutely necessary investigation in most cases as the mainstay of treatment is supportive with rehydration and the correction of electrolyte imbalance. However, stool cultures should be sent from patients with symptoms which are persistent or severe enough to prompt the patient to seek medical attention. Cultures are also mandatory in cases of bloody diarrhoea and signs of systemic involvement. The cultures should be sent within 3 days of admission as the yield is significantly reduced beyond this time period – and results take 2-4 days to become available.
This condition is more common in the extremes of age and complications are also more common in these groups. The commonly examined complication is haemolytic uraemic syndrome, which develops in 10% of patients with E coli O157 infection. Another complication is death, which is uncommonly examined but needless to say most patients who die from infectious diarrhoea are at the extremes of age. Diarrhoeal illness in young infants under 2 years of age is characteristically caused by EPEC (enteropathogenic E coli). Use of antibiotics is controversial and in most cases is not necessary (except possible in traveller’s diarrhoea).
A 30 year old, man became unwell 4 weeks after a holiday in Africa. He developed headaches, muscle pains, feeling cold, severe rigors, high fever, flushing, vomiting and profuse sweating.
A. Toxoplasmosis B. Syphilis C. Enteric fever D. CMV (cytomegalovirus) E. Tetanus F. Tuberculosis G. Giardiasis H. Malaria I. Herpes zoster (shingles) J. HIV K. Influenza L. Rabies M. Viral hepatitis N. Glandular fever O. Cholera P. Polio
H. Malaria - In the Western world, almost all cases of malaria occurs in travellers so an adequate travel history is crucial or the diagnosis may be missed. Malaria is endemic in many parts of Africa and this is a clue. Patients typically present with non-specific symptoms such as a fever, sweats, chills and myalgia. Sometimes EMQs will describe patterns of fevers occuring at regular intervals of 48-72 hours associated with P. vivax, P. ovale and P. malariae infections but in most patients there is no specific pattern. The test of choice is Giesma-stained thick and thin blood smears. Thick films sensitively detect parasites whereas thin films allow species identification and calculation of parasitaemia to guide treatment. Note that blackwater fever is a complication of malaria which occurs due to haemolysis and the release of haemoglobin into blood vessels and subsequently into the urine, which can frequently lead to renal failure.
A 50 year old man became unwell after a holiday in India. He developed a fever, tiredness, night sweats and a productive cough. He lost half a stone in weight since his return from holiday 6 weeks ago.
A. Toxoplasmosis B. Syphilis C. Enteric fever D. CMV (cytomegalovirus) E. Tetanus F. Tuberculosis G. Giardiasis H. Malaria I. Herpes zoster (shingles) J. HIV K. Influenza L. Rabies M. Viral hepatitis N. Glandular fever O. Cholera P. Polio
F. Tuberculosis - The patient’s symptoms and travel history point towards pulmonary TB. It is important to have a high level of suspicion when evaluating patients with risk factors who present with suggestive symptoms. Night sweats, fever, malaise, cough, haemoptysis and erythema nodosum are all suggestive. Key risk factors for pulmonary TB include exposure to infection and returning from or being born in a high-risk region such as Asia, Africa and Latin America. If TB is suspected, the patient should be placed in isolation and a CXR obtained with 3 sputum samples cultured for AFB being the gold standard of diagnosis. Culture on solid media can take 4-8 weeks so sputum smears will be done before culture results are known. Interferon-gamma release assays (IGRAs) are now used by some hospitals to rapidly determine a patient’s TB status. All patients who have TB should be tested for HIV within 2 months of diagnosis.
Classically, in primary disease CXR shows middle and lower zone infiltrates. Post-primary TB usually involves apical changes with or without cavitation. However, recent students have indicated that both presentations are seen in both primary and post-primary TB. HIV positive patients tend to have a more atypical CXR including effusion, lower zone involvement and a miliary pattern.
A 20 year old student presented with a sore throat, fever, anorexia, malaise and lymphadenopathy. She was treated for tonsillitis by her GP but did not complete the course because she developed an allergic rash.
A. Toxoplasmosis B. Syphilis C. Enteric fever D. CMV (cytomegalovirus) E. Tetanus F. Tuberculosis G. Giardiasis H. Malaria I. Herpes zoster (shingles) J. HIV K. Influenza L. Rabies M. Viral hepatitis N. Glandular fever O. Cholera P. Polio
N. Glandular fever - EBV causes a maculopapular pattern after ampicillin, which is what this patient has been given. Infectious mononucleosis (glandular fever) is caused by EBV and is characterised by fever, pharyngitis and lymphadenopathy. Enlargement of the spleen also begins in the first week and lasts 3-4 weeks, occuring in half of all cases. Risk factors for EBV transmission include kissing and sex (your 20 year old student here). A FBC will show an atypical lymphocytosis. Confirmation of IM involves detection of the existence of heterophile antibodies using the Paul Bunnell monospot. A more accurate test is a serological test detecting EBV specific antibodies. Treatment is usually symptomatic but IM carries rare but potentially life threatening complications.
A 60 year old diabetic man with fever, malaise, headache and muscle pains. After a few days he became very ill and is now confined to his bed with a hot water bottle.
A. Toxoplasmosis B. Syphilis C. Enteric fever D. CMV (cytomegalovirus) E. Tetanus F. Tuberculosis G. Giardiasis H. Malaria I. Herpes zoster (shingles) J. HIV K. Influenza L. Rabies M. Viral hepatitis N. Glandular fever O. Cholera P. Polio
K. Influenza - Diabetics are more suspectible to infectious such as flu. This is an acute respiratory tract infection caused by seasonal viral influenza A or B, hence antibiotics would have no effect. It is characterised by respiratory symptoms including rhinorrhoea, cough, fever, chills, headache and myalgia. Examination can be expected to be otherwise unremarkable. Antigenic change presents a challenge in creating new vaccines as there is no incremental protection from previous vaccinations. There have been 4 pandemics since 1918, the recent one being ‘swine flu’ in April 2009, caused by new gene rearrangement of human, avian and swine influenza.