Fever and thrombocytopenia in a returning agricultural worker
A 34-year-old man from a rural district in the south of the country presents to the emergency department in late June with 5 days of fever up to 39.4°C, severe headache, myalgia, and one episode of vomiting. He works as a shepherd and reports removing ticks from himself and his dog two weeks ago. Examination: alert but flushed, conjunctival injection, no neck stiffness, no rash. Blood pressure 105/65 mmHg, pulse 96/min, temperature 38.9°C. Laboratory results: platelets 58 ×10⁹/L, white cells 3.1 ×10⁹/L, hemoglobin 128 g/L, AST 140 U/L, ALT 96 U/L, creatinine 110 µmol/L, CRP 42 mg/L. Peripheral smear shows no schistocytes. The nearest laboratory able to perform confirmatory serology and PCR is 180 km away and results will take 48-72 hours. The patient lives alone and has no one to observe him at home.
1. Outline your initial diagnostic and disposition plan, justifying each decision with the information given.
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The syndrome is a febrile illness with leukopenia, thrombocytopenia, and transaminase elevation after tick exposure in an endemic rural setting in early summer. Crimean-Congo hemorrhagic fever is the priority concern because of its epidemic potential, high case-fatality, and nosocomial transmission risk; tick-borne rickettsiosis, anaplasmosis, and leptospirosis are plausible alternatives.
Disposition: admit to a single room with contact and droplet precautions, dedicated equipment, and restricted visitors, because he cannot be safely observed at home and the platelet count is below 100 ×10⁹/L. Do not wait for the distant laboratory. Draw paired acute sera and an EDTA whole-blood sample for PCR before any treatment, label them as high-risk biological material, and arrange courier transport with prior notification of the reference laboratory.
Notify the public health authority immediately - suspected CCHF is a notifiable disease and triggers contact tracing of anyone with exposure to his blood or body fluids. Obtain a careful exposure history from family and any healthcare workers who handled him before precautions were applied.
Baseline coagulation screen, fibrinogen, and daily platelet and transaminase monitoring are essential because deterioration typically occurs in the second week. Avoid intramuscular injections and NSAIDs. Do not start empiric ribavirin routinely before confirmation unless there is clinical deterioration, and never start it without discussing the limited evidence base; if used, it is given orally or intravenously under protocol with monitoring. Empiric doxycycline may be considered for rickettsial cover while awaiting results if there is no strong contraindication, but it must not delay isolation measures.
2. On day 3 the platelet count falls to 22 ×10⁹/L, the patient develops gum bleeding and melena, and his INR rises to 1.9. What are your immediate priorities?
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This is progression to the hemorrhagic phase, which carries a high mortality and a high risk of nosocomial transmission. Immediate priorities:
Escalate infection control: move to a negative-pressure room if available, enforce full PPE with double gloves, fluid-resistant gown, face shield, and strict sharps discipline; restrict staff to a small trained team and keep a log of all entrants.
Resuscitate and support: secure two large-bore intravenous lines, take blood for crossmatch, full blood count, coagulation, fibrinogen, renal and liver function, and lactate. Transfuse platelets for active bleeding with severe thrombocytopenia, and give fresh frozen plasma for coagulopathy with bleeding. Target hemoglobin to maintain adequate oxygen delivery rather than a fixed threshold. Avoid intramuscular injections and rectal procedures.
Consider ribavirin under the local protocol after discussion with the infectious diseases consultant, acknowledging that evidence is limited and it is not a substitute for supportive care.
Investigate the bleeding source: urgent endoscopy is high-risk and should be done only if it will change management, with full PPE and senior involvement.
Reassess for disseminated intravascular coagulation and multiorgan failure; involve critical care early and discuss goals of care with the patient while he is still able to participate.
Update the public health authority and begin post-exposure risk assessment and monitoring of exposed contacts, including staff and family.