Chikungunya Fever: Diagnosis, Differentials, and Management Guidelines

1. 👁️‍🗨️ Signs & Symptoms (Clinical Presentation)

System	Findings
Systemic	High-grade fever (acute onset), chills
Musculoskeletal	Severe polyarthralgia (bilateral, symmetric, especially hands, wrists, ankles), may persist for weeks to months
Dermatologic	Maculopapular rash (trunk/extremities), pruritic
Ocular	Conjunctivitis (non-purulent)
Neurologic (severe cases)	Encephalitis, seizures, Guillain-Barré (rare)
GI	Nausea, vomiting, abdominal pain
Others	Headache, retro-orbital pain, fatigue

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2. 🔬 Investigations

A. 🧪 Specific (Virologic)

Test	Timing	Result
RT-PCR for Chikungunya	Day 1–5	Detects viral RNA
Chikungunya IgM	After Day 5	Confirms recent infection
Chikungunya IgG	Week 2+	Confirms past exposure

Note: ELISA for IgM/IgG is standard in many low-resource settings.

B. 🧪 Non-Specific

Test	Result
CBC	Leukopenia, mild thrombocytopenia
CRP/ESR	↑ inflammation
LFT	Mild AST/ALT elevation
Creatinine	Dehydration risk
Dengue NS1/IgM/IgG	Co-infection exclusion
Zika RT-PCR	In pregnant patients
Malaria smear	Endemic areas

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3. 🧠 Diagnosis Criteria

A. Suspected Case

• Acute fever + arthralgia + epidemiological exposure (travel/residence in endemic area)
  

B. Probable Case

• Above + positive Chikungunya IgM or RT-PCR
  

C. Confirmed Case

• RT-PCR or IgM seroconversion (IgG also useful in serial testing)

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4. 🔄 Differentiation Table: Chikungunya vs Dengue vs Zika vs Yellow Fever

Feature	Chikungunya	Dengue	Zika	Yellow Fever
Fever	High-grade	High	Low/moderate	High
Joint pain	Severe (disabling)	Mild	Mild	Rare
Rash	Yes	Yes (petechiae possible)	Yes	Occasionally
Bleeding	Rare	Common (hemorrhagic)	Rare	Common in severe
Conjunctivitis	+/-	No	Yes	No
Neurologic	Rare but possible	Rare	Congenital Zika syndrome	Yes (encephalopathy)
IgM ELISA	Yes	Yes	Yes	Yes
Vector	Aedes	Aedes	Aedes	Aedes, Haemagogus
Special risk	Chronic arthritis	Shock, bleeding	Fetal malformations	Hepatic necrosis, death

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5. ⚠️ Severity Grading for Chikungunya

Grade	Description
Mild	Fever, arthralgia manageable, no complications
Moderate	Dehydration, moderate pain, needs supportive care
Severe	Neurologic signs, hemorrhage, organ dysfunction, pregnant with complications

🏥 Severe cases = Admit + consult Internal Medicine or Infectious Disease

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6. 📅 Follow-up and When to Consult

🗓️ Follow-up

• 7–10 days post-acute phase to evaluate resolution

• At 3 weeks if joint pain persists → screen for post-viral arthritis

• Monitor for secondary infection or Dengue co-infection
  

🧑‍⚕️ Consult Internal Medicine / ID if:

• Severe arthritis >2–4 weeks (may need steroids)

• Neurologic symptoms

• Suspected coinfection (Dengue, Zika, Malaria)

• Chronic comorbidities (diabetes, CKD, immunosuppressed)

• Pregnant patient with systemic involvement
  

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7. 🩺 Management Summary

🧊 A. Acute Phase (Day 1–10)

Treatment	Dosage/Details
Paracetamol	500–1000 mg PO q6h (max 4 g/day)
Hydration	Oral/IV fluids (based on clinical status)
❌ Avoid NSAIDs initially	Until Dengue is ruled out
Antihistamine (rash)	Chlorpheniramine 4 mg tid

🧩 B. Persistent/Post-viral Arthritis

Step	Treatment
1️⃣	NSAIDs: Ibuprofen 400 mg tid OR Naproxen 250–500 mg bid
2️⃣	If no response → Prednisolone 5–10 mg/day PO x 5–10 days, taper
🔁	Refer to a rheumatologist if symptoms > 6 weeks

🚨 C. Severe Case / Hospitalization (IPD)

• Admit, monitor vitals, IV fluids

• Rule out sepsis, dengue shock

• Pain control: IV Paracetamol ± Tramadol

• Specialist referral
  

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🗃️ Prescribing Example for Outpatient (RDU-compliant)

• Paracetamol (500 mg) 1 tab q6h PO PRN for fever/pain

• ORS sachet 1 packet in 1L water q2h

• Chlorpheniramine (4 mg) 1 tab PO tid for rash

• Ibuprofen (400 mg) 1 tab PO tid after meals (ONLY if dengue ruled out)
  

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📌 Take-Home Clinical Pearls

• Suspect Chikungunya in patients with acute fever + disabling joint pain

• Do not use NSAIDs until dengue is excluded

• Watch for post-viral arthritis

• Pregnant and elderly = high-risk → consult early

• Follow-up arthritis beyond 2 weeks → rheumatology