Infectious Diseases Module 3

A 35 year old man is undergoing dental procedure.

Which of the following poses the strongest indication for prophylactic antibiotic against endocarditis?

Which of the following is the most common fungal infection in immunocompromised patients?

Which of the following carries the highest mortality rate in immunocompromised patients with invasive fungal infection?

A 26-year-old man who just returned from the Solomon island a week ago presents with a two-day history of fevers, rigors, headache, malaise, nausea and vomiting, dry cough, mild arthralgia and backache.

He denies any symptom of shortness of breath, diarrhoea, neck stiffness or photophobia. He had taken doxycycline regularly as malarial prophylaxis.

On day 3 after the onset of the illness he develops a rash over his trunk and face. A petechial rash was noted on his lower limbs.

Which of the following is the most likely diagnosis?

What is the most common cause of fever in a returned traveller?

For which one of the following conditions is there the best evidence of benefit from systemic corticosteroids?

Which of the following Plasmodium species causes the most virulent form of malaria?

A 35-year-old man returned from a holiday in Africa. He was taking mefloquine antimalarial prophylaxis until two weeks after his return to Australia. Eight weeks later he presents with fever and rigors. A blood film examination demonstrates Plasmodium vivax in 1% of red cells.

Which one of the following is the most appropriate management?

A 15-year-old girl who emigrated from Zimbabwe 18 months ago presents with a three month history of recurrent painless terminal gross haematuria. Several mid stream urine specimens show a large number of red cells, white cells 100-500 per cm3 and 2+ protein on dipstix but there was no significant bacteria growth.

Renal function is normal as is renal ultrasound. Urine microcopsy shows the following:

What is the most appropriate treatment?

A medical student returns from his elective in rural Thailand and is hospitalised with an acute febrile illness associated with myalgias. He quickly develops hypotension, acute renal failure, interstitial pneumonitis, aseptic meningitis with associated hepatosplenomegaly and jaundice.

Which one of the following is the most appropriate treatment?

A 12-year-old boy presents with a two day history of severe right iliac fossa pain. The illness started with vomiting, as well as high fevers and diarrhoea. On examination, he is tender in the right iliac fossa, with the remainder of the physical examination unremarkable.

Which of the following organisms is most likely to cause this clinical picture?

The most common cause of diarrhoea in an adult traveller to a developing country is:

A 22-year-old man presents with ten days of fever that started three weeks after returning from visiting family in Bangladesh. He complains of headache, abdominal pains, anorexia, a dry cough and generalised muscular aches and pains.

On examination he looks ill. Temperature is 40.5 degrees Celcius, pulse 92/minute and blood pressure 120/65 mm Hg. On auscultation he has a clear chest. There is generalised abdominal tenderness without rigidity or guarding.

Blood tests show:

• haemoglobin 140 g/L [130-180]
• white cell count 3.5 x 109/L [4.0-11.0]
• blood films are repeatedly negative for malaria. 
• renal function, electrolytes, liver enzymes and chest X-ray are normal.

What is the most appropriate treatment?

A 50-year-old male has a two month history of frequent, small volume stools associated with cramps and flatulence. This has occurred since returning from a holiday in South East Asia.

The empiric treatment most likely to be successful is:

A 25-year-old man presents six weeks after a trip to central Africa with fever, chills and rigors.

Stool examination is positive for Entamoeba histolytica. An ultrasound reveals a 7.5 cm liver abscess.

The most appropriate next step in this patient’s management is:

Which of the following is least likely to be associated with a rash?

Which of the following is the most life threatening fungal infection requiring urgent surgical debridement of the devitalized tissue?

A 72-year-old patient on total parenteral nutrition (TPN) becomes unwell and develops a fever. A blood culture is reported as growing Candida krusei.

In addition to treatment with amphotericin B, which one of the following management strategies is most appropriate?

A 72-year-old patient with pancreatitis on total parenteral nutrition (TPN) develops a persistent fever. Blood cultures grow Candida kruzei.

Which one of the following would be the most appropriate?

Other than bacterial infections, opportunistic infection with which of the following is most likely to occur in a patient after induction chemotherapy for acute myeloid leukaemia (AML)?

An 15-year-old girl has undergone a T-cell depleted unrelated bone marrow transplant for relapsed acute lymphoblastic leukaemia. Recovery is complicated by slow neutrophil engraftment, grade 3 acute graft-versus-host disease requiring high dose methylprednisolone, and persistent fevers.

The computerised tomography (CT) scan of her chest, performed at day +50 post-transplantation, is shown below.

Which one of the following pathogens is most likely to be responsible for the CT scan findings?

A previously well 18 year-old male presents to the Outpatient Department with a three months history of cough. On examination his temperature is 37.8oC and there is reduced air entry in the right upper lobe.

He has no unwell contacts and has not travelled outside Australia since visiting extended family in the Philippines three years ago.

His chest X-ray is shown below.

Which of the following is the most appropriate initial treatment?

Which of the following factor is highly predictive of the development of multidrug resistant TB (MDR-TB)?

Which of the following strategies has shown to be the most effective method in reducing the incidence of infections with multi-resistant Mycobacterium tuberculosis in a population?

A 20 year old female from South East Asia presents with recent history of cough,night sweats and weight loss.She has several children at home who are well.

Her sputum is positive for acid fast bacilli.

What is the most appropriate initial intervention?

A 60-year-old gentleman is diagnosed with endocarditis caused by Streptococcus bovis, which has been promptly and effectively managed. Given this diagnosis, there is a heightened suspicion for an underlying malignancy.

Which type of cancer is this patient most likely predisposed to?

Which of the following is NOT an indication for surgery in native valve infective endocarditis?

Native valve endocarditis in an intravenous drug user is most likely to be caused by?

A 50 year old man presents with severe community acquired pneumonia. He has a history of immediate hypersensitivity to penicillin.

What is the most appropriate antibiotic therapy?

A 40-year-old gentleman is grappling with a severe case of pneumonia. His sputum analysis reveals the presence of Methicillin-Resistant Staphylococcus Aureus (MRSA).

Despite being administered vancomycin, with trough levels maintained at 20 mg/L, his condition continues to deteriorate, marked by persistent hypoxia, fever, and ongoing positive cultures. The vancomycin Minimum Inhibitory Concentration (MIC) stands at 2 mg/L, yet his clinical status is worsening.

What would be the most judicious next step in his treatment plan?