Fever in the returned traveller — formative SAQs

SAQ 1 (10 marks)

A six-year-old boy is brought to the emergency department with three days of high fever, headache and increasing drowsiness. He returned five days ago from a three-week visit with grandparents in rural Papua New Guinea and took no malaria prophylaxis. On examination he is febrile to 39.8 °C, drowsy but rousable, pale, with deep acidotic breathing and an enlarged spleen. There is no rash or eschar. [1]

Question: Outline your immediate assessment, the investigations you will send, and the principles of management for this child. (10 marks) [2]

Model answer

Immediate recognition and resuscitation (3 marks). This child has possible severe falciparum malaria — a febrile, drowsy, acidotic, splenomegalic child days out of a malaria-endemic area with no prophylaxis — and he is in a resuscitation pathway, not an outpatient one. Perform a structured ABC assessment with a paediatric early-warning score, give high-flow oxygen for the respiratory distress, and secure intravenous access. Send the first blood draw for the investigations below and include the malaria film in that first draw, because the film is part of the resuscitation. [11]

Investigations (3 marks). The non-negotiable test is an urgent thick and thin malaria blood film examined on the same day, with a rapid diagnostic test as an adjunct where microscopy may be delayed. Add a full blood count and film, venous gas and lactate, glucose, urea and electrolytes, liver function tests, C-reactive protein, blood cultures (before antibiotics where possible) and a urinalysis. State the key pitfall explicitly: a single negative film never excludes malaria, so the film is repeated at twelve- to twenty-four-hour intervals — and sooner if he deteriorates — until malaria is found or an alternative diagnosis is secured and the clinical course fits. [6] [11]

Severity-driven management (3 marks). The drowsiness, acidotic breathing and pallor meet criteria for severe disease, so he receives intravenous artesunate immediately, without waiting for the film result. Justify the choice: the AQUAMAT trial randomised over five thousand African children with severe falciparum malaria and showed a relative reduction in mortality with artesunate compared with quinine, and artesunate is faster-acting, safer and easier to give. In parallel, give empiric broad-spectrum antibiotics (ceftriaxone) because bacterial sepsis cannot be excluded and dual pathology occurs. Once the film is positive and parasitaemia is falling, he completes a full course of oral artemisinin-based combination therapy. [5] [6]

Monitoring and disposition (1 mark). Admit to high-dependency or intensive care and monitor the conscious level, lactate, haemoglobin and urine output, watching for the complications of severe disease (cerebral oedema, renal failure, severe anaemia) and for post-artesunate delayed haemolysis weeks later. Involve paediatric infectious diseases and notify the case as required. [5]

SAQ 2 (10 marks)

Question: Describe the five must-not-miss causes of fever in the returned traveller, and for each give the time-critical therapy and one key diagnostic or management pitfall. (10 marks) [2]

Model answer

Falciparum malaria (3 marks). Time-critical therapy: intravenous artesunate for severe disease (AQUAMAT mortality benefit in African children; oral ACT for uncomplicated disease). Key pitfall: a single negative malaria blood film never excludes malaria, because parasitaemia fluctuates and low-level infection is missed — repeat the film at twelve- to twenty-four-hour intervals, and sooner if the child deteriorates. [5] [6]

Dengue (2 marks). Time-critical therapy: careful titrated isotonic crystalloid through the critical phase of capillary leak; transfusion only for significant bleeding. Key pitfall: dengue shock peaks around defervescence (day three to seven), exactly when the fever falls and the family relaxes — discharge at this transition is the classic error, so watch the haematocrit, pulse pressure and warning signs through the defervescence window. [7]

Enteric (typhoid) fever (2 marks). Time-critical therapy: an empiric antibiotic chosen by destination and resistance pattern — ceftriaxone for severe disease, azithromycin for uncomplicated suspected XDR typhoid from South Asia. Key pitfall: extensively drug-resistant Salmonella Typhi is now prevalent in South Asia and resistant to fluoroquinolones and often third-generation cephalosporins, so the empiric choice is a travel-history decision and a generic quinolone may fail. [10]

Rickettsial and scrub typhus (2 marks). Time-critical therapy: doxycycline, given on clinical suspicion at any age, because it is life-saving. Key pitfall: treatment must never wait for serology — the antibody response takes weeks and the disease can kill in days. Look for the eschar, a painless black necrotic lesion at the inoculation site, which is the single most specific clue. [11]

Viral haemorrhagic fever (1 mark). Time-critical therapy: immediate isolation, supportive care, and activation of the public-health and infectious-diseases protocol, with specific therapy (where it exists, as for Lassa) delivered within that framework. Key pitfall: the decision to isolate is made on the travel history alone — a child febrile within twenty-one days of a VHF risk zone — before any blood test or aerosol-generating procedure, because an unrecognised case is a nosocomial hazard. [2]