Microbio Flashcards
The antiviral which is given to untreated pregnant women with HIV to prevent vertical transmission of the virus during childbirth.
Nevirapine (NNRTI).
Is more effective that ZDV when given as a stat dose in childbirth.
Zidovudine can be given as monotherapy in pregnancy or in combination with Nevirapine and lamivudine.
An immunomodulatory therapy used in the treatment of hepatitis B.
Interferon-alpha.
Hep B is not treated with intereferon B
The final metabolite of the antiviral used to treat Herpes Simplex
Aciclovir triphosphate.
Resistance develops when viral tyrosine kinases mutate to reduce aciclovir to a monophosphate.
An antiviral which can be used in aerosol form to prevent respiratory syncytial virus in children with heart and lung disease
Ribavirin
The synthetic nucleoside analogue ganciclovir is the drug of choice against which infective virus?
CMV
Valaciclovir, a prodrug of aciclovir, is used to treat patients with which viral disease in the list, above?
VZV
Used for the treatment of severe, resistant herpes infections
Foscarnet - DNA polymerase inhibitor.
A drug that is effective against influenza A but not influenza B
Amantadine
A purine nucleoside analogue that selects specifically for thymidine kinase
Aciclovir
A nucleoside analogue which inhibits reverse transcriptase
Zidovudine
The drug mechanisms which acts by stopping post-translational cleaving of polyproteins by inhibiting proteases
Indinavir, Nelfinavir, Ritonavir - anything ending *navir.
The drug that is selectively toxic to virally infected cells through its selective phosphorylation using viral thymidine kinase
Aciclovir
The drug which can be delivered by inhalation to treat both influenza A and B.
Zanamivir, Oseltamivir
Ending *mivir.
A 19yr old medical student who lives in residential halls presents with a one week history of headache, malaise, shortness of breath and a cough. Her WBC is not raised but tests reveal the presence of cold agglutinins.
Mycoplasma pneumonia
Dry cough, new infiltrates on CXR, dyspnoea and target shaped lesions on the palms. No recent history of herpes.
Mycoplasma pneumonia
An 80 year old clown appears at the GP having been discharged from hospital for a complicated bowel resection with a stint in the ITU. He has a cough and fever and is prescribed a macrolide antibiotic because he is penicillin allergic.
MSSA - because being given a macrolide.
Macrolides are the drug of choice in legionella and mycoplasma, camplylobacter.
A 55 year old female clown, recovering from a cold, is found to have a cavitating lesion on CXR and a productive cough.
Flu is a classic precedent of S. aureus pneumonia. S. aureus pneumona produces cavitating lesions on CXR.
An 18 year old trainee clown is being seen in the cystic fibrosis clinic and is found to be colonised with a particularly persistent organism.
Burkhoderia cepacia
A 25 year old man with a latex allergy comes into GUM clinic with small grouped vesicles and papules on the shaft and glans of his penis. This was accompanied with severe pain in his groin, buttocks and upper thighs, a fever, and dysuria. Virology showed the presence of an alpha herpesvirus, HHV 2
Primary genital herpes
A 21 year old man came to hospital complaining of severe headache, fever, malaise and a sore throat. On examination he showed cervical lymphadenopathy, especially the posterior cervical nodes, and splenomegaly. Peripheral blood tests showed the presence of lymphocytosis with atypical mononuclear cells. The Paul Bunnell reaction was positive for heterophilic antibiodies.
Glandular fever, EBV
HSV1 is commonly assoc with
Primary stomatitis
CMV is commonly assoc with
Pneumonitis
HSV2 is commonly assoc with
Neonalta infection associated with vaginal delivery.
HHV8 is commonly assoc with
Kaposis sarcome
HHV6 is commonly assoc with
roseola infantum (Exanthem subitum)
Pneumonitis after a bone marrow transplant
CMV (beta)
Endemic Burkitt’s lymphoma
EBV (gamma)
Acute necrotising encephalitis
HSV1 (alpha)
A 43-year-old man with a known history of HIV presents to his doctor with creamy plaques coating his tongue and oral cavity. His symptoms subside after treatment with fluconazole.
Candidiasis
A 37-year-old woman with a past history of intravenous drug use presents to her GP for her methadone prescription. On examination they note pale rigid lesions on the side of her tongue. Alongside her methadone the GP prescribes aciclovir.
hairy Leukoplakia
Naturally occurring cytokine that is able to inhibit HIV fusion to CD4+ T-lymphocytes?
MIP-1a, MIP-1b and RANTES
Which viral protein is responsible for the binding or fusion of HIV to human CD4+ T-lymphocytes?
gp120
An immunocompromised HIV positive patient should not receive this vaccine.
BCG
75 year old female has been diagnosed with MRSA bacteraemia secondary to an infected leg ulcer.
Vancomycin
Treatment of an 18 year old with Meningitis
Ceftriaxone
Patient with an abdominal collection that contains gram –ve anaerobes.
Metronidazole
56 year old male with endocarditis caused by VRE.
Linezolid
C.difficile colitis where metronidazole has failed
Vancomycin
Atypical pneumonia caused by Legionella in individuals with penicillin allergy
Erythromycin
Severe systemic infection before cause has been identified
Cefuroxime
Long-term prophylactic treatment for post-splenectomy patients
Penicillin V
An 82 yr old gentleman, living at home, develops severe dyspnoea with a productive cough and fever. His PaO2 has fallen below 8kPa, and he is becoming confused.
cefuroxime and clarithromycin
A 6 month old child whose father has just been diagnosed with tuberculosis.
isoniazid
This microbes affects mainly the distal colon, producing acute mucosal inflammation and erosion. It is spread by person-to-person contact, and its clinical features include fever, pain, diarrhoea and dysentery.
Shigella
This microbe affects the ileum, appendix and colon. Its peyer patch invasion leads to mesenteric lymph node enlargement with necrotising granulomas. Complication can include peritonitis, pharyngitis and pericarditis.
Yersinia
Yersinia enterocolitica undergoes multiplication in Peyer’s patches following invasion of human epithelial cells and penetration of the mucosa which occurs in the ileum. Complications include diarrhoea, mesenteric adenitis, mesenteric ileitis, or acute pseudoappendicitis, reactive arthritis and erythema nodosum.
A 34 year old female returned from Indonesia two weeks ago. She complains of diarrhoea, abdominal pain, weight loss, nausea and vomiting for the past few days. She has no fever. Investigation reveals steatorrhoea and stools appear to contain numerous cysts.
Giardiasis
Following a trip to Brazil, a patient develops bloody diarrhoea, with a high fever, sweating and on examination the patient is found to have RUQ pain.
Entamoeba Histolyticia.
Ingestion of Entamoeba histiolytica cysts is followed by excystation in the small bowel and trophozite colonisation of the small colon. The trophozyte may then encyst and be excreted in faeces or it may invade the intestinal mucosal barrier, thereby gaining access to the circulation. Complications include amoebic colitis, liver abscesses, pleuropulmonary amoebiasis and cerebral amoebiasis.
A 40 year old homosexual man develops severe flatulence, accompanied by bloating and explosive diarrhoea.
Giardia (but could be entamoeba)
Mrs A became ill at about midnight after eating chicken wings for lunch at a summer BBQ. Mrs A complained of nausea, vomiting and non-bloody diarrhoea. Her symptoms resolved 3 days later.
Salmonella (duration too long for Brucella)
Mr S became ill with nausea, vomiting and watery diarrhoea about 4 hours after eating some ham at a conference buffet lunch. Mr B’s illness was attributed to a heat stable, preformed toxin in the ham. His symptoms resolved within 24hours.
Bacillus Cerus
Mr C complained of fever and severe (>10 bowel movements/day) diarrhoea after looking after his neighbours dogs for a few days. Laboratory analysis of Mr C’s stools found the causative organism to be a S-shaped microaerophillic bacteria.
Campylobacter
Miss D initially complained of a dry mouth and visual disturbance a few days after ingesting some home canned produce. She sought medical attention after she began to experience bilateral descending paralysis. Miss A later died from respiratory failure.
Clostridium botulinum
Cause of bubonic plauge
Yeersinia pestis
A student who presented with two day history of bloody diarrhoea, vomiting, fever, headache and myalgia. He has just returned from camping in the country side near a farm where he had fresh cow’s milk for breakfast everyday.
Campylobacter
A 2 year old boy living in the slums who has a one day history of profuse watery diarrhoea, fever and abdominal cramps. His family’s main source of water is the river near their squatters
Cryptosporidium parvum -
Parasitic disease of mammalian intestinal tract. Usually immunocompromised. Profuse diarrhoea with anorexia, nausea and vomiting, with adbo pain.
Can cause cryptosopridosis of lungs, hepatitis and cholecystitis
A man was bitten by a rat in Asia. Ten days later he complains of fever, malaise, headache and myalgia.
Siprillium minus - gram negative
Associated with rat-bite fever.
Cat-scratch disease
Bartonella henselae (or bartonella species)
A zoonosis associated with hepatitis, jaundice, conjunctival injection and renal impairment. Transmission normally occurs by direct contact with either the urine or tissues of an infected animal.
Leptospirosis (associated with rat urine in water). Corkscrew shaped bacteria
Myalgia, conjunctivits, hepatitis, renal failure.
Combination of jaundice and renal failure is Weil’s disease.
Treat with penicillin.
A 22 year old student, who returned from a holiday in the Mediterranean 3 weeks ago, presents with an undulant fever, malaise, weakness and generalized bone pain. Upon examination lymphadenopathy and hepatosplenomegaly are also noted.
Brucellosis
A 45 year old male farmer presents with a raised, erythematous rash, with clearing in the centre. He also complains of headache, fever, athralgia and malaise.
Lyme disease - rash is erythema migrans (immune mediated rash at site of the bite).
A 30 year man presented with jaundice and conjunctival haemorrhages. He had recently been canoeing in the US and had felt ‘run-down’ upon his return to the UK.
Leptospira interrogans
A 25 year old Maltese man presented to his GP with lethargy for a month and headaches and fever. On examination, he had a temperature of 39°C and one fingerbreadth splenomegaly. Small Gram-negative coccobacilli were seen on culture in Casteneda’s medium.
Brucella melitensis (Gram negative rod)
Associated with malta (maltese fever). From unpasteruised milk
Undulating fever with with muscle pain. Can cause hepatitis and neuro disorders.
A 22 year old student presented to her GP upon return from a biology field trip, with a lesion on her leg which was 3” in diameter and flat, with a red edge and dim centre. She also mentioned feeling tired and suffering from headaches. On examination, the GP noted a fever of 38.0°C and an irregular heartbeat.
Borrelia burgdorferi (causative organism of Lyme disease).
A tanner on holiday from India presented to hospital with an ulcerating papule on his hand. On inspection of the ulcer, the centre was black and necrotic. Gram-positive rods grew on blood agar culture and responded to treatment with large doses of penicillin.
Bacillus anthraticus
A 6 month old baby presents at his GP with nappy rash. Which is the most likely causative fungus?
Candida albicans
A 21 year old man presents at his GP complaining of an itchy, scaly rash on the soles of his feet. Skin scrapings are taken and sent away for microscopic examination. Which fungi might be identified?
Trichophytum rubrum commonest causative organism of tinia pedis.
E floccusum is associated with groin infgection.
A 55 year old farmer is seen in the Oncology clinic with a diagnosis of hepatocellular carcinoma. He is a lifelong teetotal and his virology has all been negative. Which fungus may have indirectly been a cause of his cancer?
Aspegillus
A 27 year old lady from Botswana presents at A+E complaining of a dry cough and feeling feverish. A chest x-ray is normal, but fine crackles were heard on auscultation. Serology shows a CD4+ count of 50 and she is admitted. Later a high resolution CT of the chest shows a ground glass appearance of the lungs. What AIDS defining infection does this lady have?
Pneumocystis carinii
A 17 year old Nigerian girl presents at her GP with patches of hypopigmentation on her trunk. After an initial trial of steroid cream, the girl returns complaining that the rash is spreading. Woods lamp examination of the rash produces a yellow fluorescence. What is the causative fungus?
Pityrosporum orbiculare (causes tinia versicolour Also malassezia furfur
A homosexual male presented with painful dyspagia and was noted to have whitish velvety plaques on the mucous membranes of the mouth and tongue. When his GP scraped away the whitish material pinpoint bleeding occurred. What is the most likely diagnosis
Candidiasis
A 47 year old man is admitted following lung transplantation three months ago with cough and breathlessness. He has a cavitating lesion on chest X-ray. At the time of his transplant, building work was being done on the hospital campus in close proximity to the surgical ward.
Aspergillosis
A 47 year old man is admitted following lung transplantation three months ago with cough and breathlessness. He has a cavitating lesion on chest X-ray. At the time of his transplant, building work was being done on the hospital campus in close proximity to the surgical ward.
Cryptococcis
Cryptococcus neoformans, is a pathogenic fungus commonly found in pigeon droppings and pigeon nests (and also soil). The predominant clinical process usually in immunocompromised pts, is a variably subacute meningitis with occasional patients showing features of brain abscess or inflammatory cerebral vasculitis, so the clinical feats are usually - headache, fever, nausea, neck stiffness, feats of raised ICP.
An 8 year-old boy presents to casualty with a painful and swollen right thigh after being kicked in a football match. On examination a boil is found on the upper part of his right thigh and blood cultures are positive.
Staph osteomyelitis
The boil is a source of infection for the bone.
A 19 year-old student presents to her GP with a macular rash and suboccipital lymphadenopathy. She also complains of pain on moving her hands and wrists.
Rubella
Gives macpap rash with lymphadenopathy and arthralgia. A reactive polyarthritis in a RA like distrubition.
A 35 year old lady with a history of TB presents with collapsed cervical vertebrae, a marked kyphosis causing difficulty in moving
Potts disease
Mr PD, a 26 year old musician, arrives in AandE with a warm, painful abscess on his inner upper forearm surrounded by puncture marks, he has a low grade fever. He reports no problem in playing his guitar, but does forget lyrics on stage.
Staphylococcus osteomyelitis
Accompanying Mr PD, is a 17 year old female (musician) with a larger, redder, painful abscess on her inner upper forearm. She has almost no movement in her elbow.
Septic arthritis
Your Consultant spotlights you to expand on the diagnosis of osteomyelitis in a gentleman with a history of sickle cell crises, presenting with bone pain and excessive sweating. On X-ray he informs you there is “cortical destruction, involucrum and sequestra”.
Salmonella osteomyelitis
Salmonella is a very rare cause of osteomyelitis, except in sickle cell disease.
It is suggested that the peculiar susceptibility of patients with sickle cell anaemia to salmonella osteomyelitis is due to spread of salmonella from the intestine facilitated by devitalisation of gut caused by intravascular sickling,
A 10 year old boy presents with moderate pain in his lower leg, little redness and swelling, remitting for 6 months. His mother gives you the X-ray report from the previous episode, which showed “a well defined ovoid shape with a surrounding sclerotic margin but little involucrum in his tibia”.
Brodies abscess
A Brodie abscess is a subacute osteomyelitis, which may persist for years before converting to a frank osteomyelitis.
Localized pain, often nocturnal, alleviated by aspirin. Often mimics the symptoms of Osteoid osteoma, which is typically
A 30 year old builder develops abdominal pain and diarrhoea 48 hours after having Texa Fried Chicken. Faecal culture shows motile, oxidase-positive colonies and gram stain shows gram-negative rods.
Campylobacter
an example where prophylactic systemic antibiotic therapy should not be used.
Removal of breast ca
A man is recovering from surgery and inspection of the wound reveals that it has become infected. A swab is taken and the laboratory results show Staphylococcal aureus infection. What is appropriate treatment for this man?
Oral Flucoxacillin
A 15 year old girl consults her GP after experiencing a high temperature and several headaches over the last three weeks. She has no medical history of note and has recently begun a weekend job helping at a local farm.
Brucellosis
An 80 year old man returns to his GP two weeks after being prescribed co-trimoxazole for a UTI. His urinary symptoms have now eased, but he is still experiencing a fever. His blood count shows eosinophilia.
Drug-induced fever
18 yr old female presents with pyrexia, jaundice and a history of lymphadenopathy and sore throat. Most likely cause?
Infectious mononucleosis
40 yr old male presents with jaundice, fever, hepatomegaly, and a positive past history of HBV. Most likely cause?
Hep D
A 20 year old male presents with a sore throat and headache. He has a maculopapular and petechial rash on his hands and feet. The CSF sample grows Gram negative diplococcus.
Neiserria Meningitidis
A 25 year old lady is brought to A&E. She complained earlier of headaches. She has a fever and speech disturbance. She starts to lose consciousness.
Viral encephalitis
A 30 year old gentleman presents with headache, fever and general malaise. He reports no neck stiffness or photophobia. A lumbar puncture revealed clear CSF with no bacteria present, a high number of lymphocytes and protein of 0.75g/L. CSF glucose was within normal range
Viral meningitis
A 42 year old East African woman presents with haemoptysis and neck stiffness and photophobia and subsequent impairment of consciousness. On questioning it is revealed that she has been feeling unwell for a couple of weeks. CSF from a lumbar puncture was turbid with a high level of protein (2.3g/L).
TB meningitis
A 3 year old girl with incomplete vaccinations presents with insidious symptoms of meningism over the course of a couple of days. Blood culture revealed presence of Gram negative coccibacilli.
Haemophilus influenzae
A 24 yr old male is brought to AandE by his distressed girlfriend. They had just returned from a 2 week stay in Scotland when her boyfriend began to feel generally unwell. Since then he has become hyperactive and becomes uncontrollable when he sees or even hears water with jerky head and body movements. On examination he is severely dehydrated and you notice a small bite mark on his shoulder. You also notice ptyalism.
Viral encephalitis
A 56 yr old male presents with fever, vomiting and seizures. Examination reveals a well established ear infection and there is a ‘ring-enhancing’ lesion on the MRI of his brain.
Cerebral abscess
The ring usually represents vasogenic oedema.
DDx cerebra abscess is tuberculoma, toxoplasmosis and CNS lymphoma.
Toxoplasmosis - raw meat, cat faeces or immunecompromised
A 1 yr old child is brought into AandE by his mother. She has noticed he has a fever and is now becoming increasingly restless and will not stop screaming. He has a non-blanching rash on his thigh.
Acute bacterial meningtis
An 18 yr old student comes in feeling ‘pretty lousy and aching all over’. She is wearing dark glasses and complains of a stiff neck. CSF examination reveals a normal CSF/blood glucose ratio and 0.7 g/L protein with a lymphocyte count of 15
Acute viral meningitis
A 70 yr old man presents with his wife. She complains that he has become increasingly forgetful and now she is unable to understand what he says. On examination you notice some ataxia and sudden spasms of his muscles. An EEG shows periodic sharp waves.
Prion disease
Used as antimicrobial treatment of UTIs during the initial stages of pregnancy. Concentrated in the urine.
Nitrofurantoin
These infections are almost invariably associated with functional or anatomical abnormalities of the renal tract. Tip: also causes cavitating pneumonia.
Klebsiella
Broad spectrum penicillin traditionally used in the treatment of UTIs
Ampicillin
One of the 1st line drugs for UTIs in non pregnant women but contra-indicated in pregnant women
Trimethoprim - teratogenic in pregnancy.
In pregnancy can use nitrofurantoin, amoxicillin or cephalexin. Nitrofurantoin shouldn’t be ucsed near term as it can cause haemolysis in neonates.
The most common cause of UTI in catheterized men
E.coli
The 2nd commonest cause of uncomplicated UTI in young women
Staph saprophyticus
Can be used as monotherapy for acute pyelonephritis and should always be prescribed orally because its bioavailability is near 100% and iv dosing is 30 times more expensive.
Ciprofloxacin
Causes haemorrhagic cystitis in children.
Adenovirus
A cephalosporin used for treating pseudomonal infections in cystic fibrosis
Ceftazidime
Given IM as a single shot for gonococcal urethritis
Ceftriaxone
A 40-year-old Indian male presents to AandE with dysuria and back pain. He has recently noticed blood in his urine and his past medical history reveals that he has had hypertension for 5 years. After some initial reluctance, he admits to having HIV, which was diagnosed on his arrival in the UK 7 years previously.
Renal TB
A 23-year-old Caucasian women presents to her GP with urinary frequency, urgency and burning. She also complained of slow stream as well as suprapubic pain. She has had several UTIs in the past and analysis of her urine showed no significant bacteruria.
Urethral syndrome
Hx of recurrent UTIs without pyuria. Symptoms of UTIs
A 42-year-old African American male presents to AandE with severe loin pain that radiates to the groin. He complains of painful urination, interrupted flow and increased urinary frequency. Urine dipstick reveals the presence of leucocytes, nitrites, haematuria and proteinuria. Intravenous uretogram shows a filling defect of the right kidney.
Calculi
A 63 year old gentleman has a two day history of fever and rigors with lower back pain and discomfort on passing urine. Urine microscopy and culture revealed 2 x 104 Escherichia Coli per ml urine.
Bacterial prostatitis
Individuals who walk or swim in the river Nile put themselves at risk of developing this condition
Schistosomiasis of bladder
A 35 year old Asian gentleman has recently migrated to the United Kingdom. He presents with urinary frequency, dysuria and loin tenderness. Urine culture is negative, however he has pyuria.
Renal TB
A sterile pyuria occurs in renal tuberculosis
A 40 year old lady was previously diagnosed with acute UTI and treated with trimethoprim. Ten days later she returns to her GP with the same symptoms of dysuria and frequency, and urine microscopy reveals a positive culture of the same bacteria.
Relapse of UTI
A relapse of a UTI implies re-infection with the SAME organism. Recurrent UTIs imply infection with DIFFERENT organisms.
A 32 year old male recently underwent a kidney transplant procedure. During his time in hospital he was continually disturbed by the noise of building work. He started to develop fever, dyspnoea an dslight confusion.
Aspergillus fumigatis
A 74 year old male is soon to undergo colorectal surgery and hospital procedures of antibiotic prophylaxis is followed.
Cef and Met 0-2h before incision and no longer than 24h post op
A 35 year old woman receiving chemotherapy for high grade lymphoma develps SOB and dry cough. CXR shows bilateral reticulonodular shadowing. A transbronchial biopsy shows alveoli filled with foamy eosinophilic material and numerous boat-shaped organisms staining positively with silver stain. Sputum culture is negative.
Pneumocystis pneumonia
A 60-year-old man was admitted for coronary artery bypass graft. Three days following his operation, his blood culture grew coagulase-positive staphylococcus spp. which was resistant to flucloxacillin. His wound swab also grew the same organism. Identical isolates were obtained from four other adjacent patients and were also found in the nasal swabs of one of the surgeons. These isolates were subsequently shown to be of the same phage-type.
MRSA
A 50-year-old man was admitted with acute pancreatitis and underwent emergency pancreatectomy. He was in ITU for four weeks for respiratory support where he remained febrile and septic. Blood cultures and wound swabs grew gram-positive cocci in chains, which grew on MacConkey plate and was aesculin-positive. This isolate was also resistant to the conventional anti-streptococcal antibiotics.
VRE
A patient with 20% burns with open wounds is awaiting skin grafting. The wound swab grew gram-negative bacilli that produced a green pigment and was oxidase-positive. A similar organism was isolated from other patients on the same unit. Bacteriological typing subsequently proved all the isolates were of the same type
Pseudomonas aeruginosa
Three patients on the same ward/medical firm came down with diarrhoea and vomiting within 24 hours. The attention is drawn to the ward sister that many patients started their symptoms at the same time. Stool samples were sent for bacterial cultures and viral studies. Subsequently, the diagnosis was obtained by electron microscopy, which showed the same pathogen for all patients.
Rotavirus
Sitting in on your consultant’s GUM clinic, you see a shy 30-year-old woman who admits to losing her virginity a week ago and now is worried about the appearance of insect bite-like marks in her genital region and a concurrent fever. On intense questioning, she reveals that her partner seemed to have a painful sore on his penis
HSV2
On Tuesday, a confident African friend comes to you for advice. He has noticed a painful ulcer on his penis, from which he has helpfully collected exudate. Sneaking into the labs at Chelsea and Westminster late one evening, you culture this. Later, you note the presence of Haemophilus ducreyi.
Chancroid.
STI characterised by painful sores on genetalia. Usually due to haemophilus ducreyi in developing countries.
On Thursday evening, you receive a panicked phone call from your mother. Your 16-year-old sister, whom you have always been close to (since her diagnosis at age 3 with a complement disorder), has been feeling feverish, has a rash and painful joints. Suddenly, you remember having seen Jim, one of her many ‘boyfriends’, secretively sneaking out of GUM clinic. You vaguely remember that microscopy showed a gram negative diplococcus
Disseminated gonococcal infection
After a Friday night out, you return to your room in halls with Helga, a promiscuous fellow student on your corridor. Before copulating, you notice Helga has some muco-purulent discharge from her vagina. Upon questioning, she admits to a history of pelvic pain.
Chlamydiae Trachomatis
A 45 year old female presents with fever. O/E she is pyrexial, has hepatosplenomegaly, lymphadenopathy and a severely swollen eyelid. She returned from Guatemala 2 days ago.
Chagas Disease (american trypanosomiasis)
Parasitic disease by protazoan Trypanosoma cruzi.
Initial - fever, fatigue, aches, rash, diarrhoea. Mild hepatosplenomegaly, lymphadenopathy and local swelling where parasite entered body. Romoana’s sign is swelling of eyelid.
Can progress to cardiomypoathy, digestive problems and enecephalopathy.
A 21 year old female presents with chronic diarrhoea beginning 2 days before her return to the UK from India 3 weeks ago. She has lost weight, feels bloated and also complains of very offensive burps.
Giardia
A 35 year old male complains of a persistent ulcer in the mucosa of the mouth. When questioned further admits to remembering a small ulcer on his upper arm which healed without treatment when holidaying in Brazil one year ago.
Mucocutaneous leishmaniasis
Cause by protazoa of leishmania genus via bite of sandflies. can be cutaneous, mucocutaneous or visceral. Initially with ulcers and then progresses to fever, low RBCs and hepatosplenomegaly.
Tropical sprue
Malabsorption due to inflammation in lining of small intestine.
Sx- diarrhoea, steatorrhoea, indegestion, cramps, weight loss and fatigue.
Tropical sprue should be considered in symptomatic patients who have lived for more than one month in an area where tropical sprue exists.
A 45 year-old Egyptian male complains of haematuria. On further investigation, cystoscopy reveals a squamous cell carcinomatous lesion.
Scistosoma haematobium.
S.haematobium migrates to the bladder and gives LUTS.
S.mansoni migrates to the gut and gives bloody diarrhoea.
An African woman and her 33 year-old husband come to their doctor because she is worried that he is not as alert as he used to be. On examination, he has non-tender lymphadenopathy, hepatomegaly and marked CNS abnormalities. He is noted to be quite lethargic.
African trpanosomiasis (sleeping sickness). Trypanosoma brueci gambiense (there is also a rhodesienese variety but gambiense cause 98% of cases). Two phases: haemolytic with intermittent fever, headache, arthralgia and itching, lymphadenopathy and hepatomegaly. CNS phase with altered sleeping cycle, confusion.
A thin peripheral blood film from a 59 year-old female demonstrates eosinophilia and microfilariae. On examination, the skin overlying her superficial lymph nodes is streaky red and tender
Wuchereria bancrofti (parasitic worm causing lymphatic filariasis) Sx - lymphoedema, fever, chills, skin infection, painful LN and tender skin over LNs. Later phase is obstruction of lymph and lymph varices, elephantitis. Wucheria bancrofti is characterised by the detection of microfilariae in peripheral blood, marked eosinophilia and symptoms affecting the lymph nodes.
A 43 year-old Asian male with AIDS presents with a prolonged fever, dizziness and a persistent cough. On examination, he is found to have marked splenomegaly and rough, dry skin. Blood results reveal pancytopenia.
Leishmania donovani (visceral leishmaniasis) is an opportunistic infection in HIV leading to prolonged fever, splenomegaly, leukopenia and hypergammaglobulinaemia. Pancytopenia may also occur. Patients present with fatigue, weight loss, dizziness, cough and diarrhoea. An uncommon feature is xerosis (rough dry skin). In contrast, pneumocystis carnii infection presents with a non- productive cough, fever and dyspnoea.
A 20 year-old man presents with a persisting intermittent fever which began whilst he was travelling in South America the previous week. He has a dry cough and a massively enlarged spleen. Sandfly parasites are detected in a spleen aspirate.
Visceral leishmaniasis (kala-azar)
A 16 year-old boy complains that his friends keep ‘taking the mick’ out of his ‘smelly, eggy burps’. He also mentions he has experienced some diarrhoea and abdominal pain.
Giadiasis
A 55 year-old Gambian man presents with a low-grade fever which has been coming and going for about 2 months. He says it started when visiting his family in Gambia when he was also feeling weak and sleeping a lot.
Trypanosomiasis
A 7 year-old girl presents with a few week’s history of fever, malaise and weight loss. She has hepatosplenomegaly and neck stiffness. Chest x-ray shows diffuse, small, nodular opacities.
Miliary TB
A 25 yr old female humanitarian volunteer complaining of swinging fever, profound abdominal pain with severe malaise. On further questioning she reveals a history of self limiting diarrhoeal illness 3/52 ago during which she passed mucus and some blood. You are also informed she recently returned from a humanitarian mission to Ghana 6/52 ago. O/E she is unwell with exquisitely tender hepatomegaly. You also find increased breath sounds and a dull percussion note in the lower region of the right lung.
Entomoeba hystolytica
A 24 yr old male complaining of 3/52 history of fever/chills with muscular aches and spasms. On further questioning he reveals the he also an episode of diarrhoea/vomiting with a headache lasting 48hrs. This followed his participation in an amateur eating competition 1/12 ago, during which he may have eaten some improperly cooked pork. O/E he has marked periorbital oedema with conjunctivitis. Blood tests reveal a marked eosinophillia, while gastrocnemius biopsy demonstrates the presence of encysted larvae.
Trichinella spiralis
parasite in rodents, pigs and horses causes trichonosis.
From eating undercooked meat infected with LARVAE.
Enteral phase - nausea, heartburn, diarrhoea. Eosinophillia.
Paraenteral phase - oedema, clasically periorbital.
A 32 yr old female complaining of the presence of small pale bodies in her stools on a number of occasions. On further questioning she admits some occasional mild epigastric pain over the past 4/12. O/E she appears clinically well. There is no significant travel history.
Taenia saginata (beef tapeworm) usually asymptomatic but can cuase abdo pain, diarrhoea, nausea and constipation.
A 35 yr old male presented with bloody, mucoid diarrhoea, headache, nausea and anorexia. He had recently returned from a holiday in the tropics with his male partner. On examination of his stool, E. histolytica trophozoites were present.
Ameobiasis
A 25yr old man who had recently returned from travel in Afrcia presented with fever, diarrhoea and hepatoslenomegaly. He also noted skin changes which had developed over the past month.
Visceral leishmania
A 40 yr old Indian lady who was vacationing in the UK presented with fever which followed no particular pattern, vomiting and the production of brown-black urine.
Malaria
A 25 year old man presents with weight loss and diarrhoea. He has recently been on holiday in India. On examination of his stool cysts and “tear-drop” shaped trophozoites are present.
Giardiasis
The CT scan of a neonate shows diffuse intracranial calcification and hydrocephalus. On questioning, his mother tells you that she used to work in a slaughterhouse and has five cats.
Toxoplasma gondii
A 10 year old girl presents with fever, hepatomegaly, splenomegaly and anaemia. She recently emigrated from the Sudan. Her mother tells you that 6 months ago the girl developed dark patches on her hands and forehead.
Leishmania donovani
An 18 month old girl from Brazil sees you whilst on a short holiday in Britain. Her parents are worried because she appears to have had fever for the last few weeks, seems more tired and out of spirits than usual, has loss of appetite, vomiting and diarrhoea and complains of pains in her legs. On examination she has general lymphadenitis and non-pitting oedema in her legs and feet. Her Machado-Guerreiro test is positive.
Trypanosoma cruzi
A 2 week old infant develops swollen red eyelids. The mother explains that the initial ocular discharge seen at 10 days was watery, but has become copious, thick and purulent. Mother, father and infant are shown to all be infected with the same bacterium and are treated with penicillin.
Chlamydial conjunctivitis in the newborn
Chlamydial ophthalmia
A French mother brings her 2 month old daughter with fever to hospital. The infant is shown to have elevated hepatic enzymes and is treated with pyrimethamine, sulphadiazine and folic acid for a year after appropriate investigations are performed.
Congenital Toxoplasmosis
An infant is born prematurely and subsequently has low birth weight. In addition, he has encephalitis and vesicular skin lesions. Despite being recommended to have a caesarean due to active viral lesions, the mother refuses and the neonate was delivered vaginally. Emperic Acyclovir is given to the neonate.
Neonatal Herpes Simplex Infection
A 2 week old female had an enlarged liver and spleen and her skin was tinged yellow. She was not eating much nor was she vomiting. She also suffered from regular seizures. Investigation revealed intra-cranial calcification.
Congenital toxoplasmosis
A newly born male presented with microphthalmia, deafness and hepatosplenomegaly. His platelet count was 50 x 10^9/L. In addition, rashes were noticed on his body. He suffers from SOB and is unable to finish feeding.
Congential rubella
A prematurely born 1 week old infant presented with microcephaly, chorioretinitis and vesicular skin lesions. He also had non-specific features of fever, irritability and failure to feed.
Neonatal HSV
A 31 year old man presents to a GUM clinic complaining of pain on passing urine and a penile discharge. His history reveals that he had travelled to Bangkok 10 days earlier “on a business trip”. On examination he had a purulent urethral discharge and a swollen tender prostate. Gram negative diplococci were found in smears of the discharge and culture of the causative agent confirmed the presumed diagnosis.
Gonorrhoea
27 year old male presents with urethral discharge and urethritis for several days. Culture of organisms present produced gram negative oxidase positive diplococci
Neisseria gonorrhoea
19 year old woman presents with cervicitis, erythema and oedema. Cultures were unable to be grown with agar but were subsequently grown using tissue medium.
Chlamydia
29 year old male presents with a painless ulcer on the penis. The lesion organism was identified using dark ground microscopy to show treponemes.
Syphilis
Presents as a shallow painful ulcer, sometimes progressing to a lymphadenopathy.
Chancroid (not herpes due to the lymphadenopathy)
Disseminated infection of this STI can be found in people with deficiencies in late complement components
Gonorrhoea
Causative organism is Haemophilus Ducreyi
Chancroid
A neonate is referred and presents with skin lesions, lymphadenopathy and failure to thrive.
Syphilis
A 22-year old male medical student is prescribed erythromycin after presenting with mucopurulent discharge. No gram negative organisms seen.
Chlamydia
