Coxiella Burnetii - IgM antibody, Serum

Bacterial/ Viral

Report in 216Hrs

At Home

No Fasting Required

Details

Detects antibodies to Q fever agent.

₹2,176₹3,108

30% OFF

Coxiella Burnetii - IgM Antibody Serum Test Information Guide

Why is it done?
- Test Purpose: Detects Immunoglobulin M (IgM) antibodies against Coxiella burnetii, the causative agent of Q fever, to identify acute or early-stage infection
- Primary Indications: Evaluation of suspected Q fever in patients presenting with fever of unknown origin, pneumonia, hepatitis, or exposure to infected animals or animal products
- Clinical Symptoms Prompting Test: Fever, chills, headache, myalgia, fatigue, cough, and chest pain typically appearing 2-3 weeks after exposure
- Timing of Test: Ordered early in acute infection (first 1-2 weeks after symptom onset); IgM antibodies typically appear within 3-5 days of illness onset
- Risk Group Screening: Occupational exposure in veterinarians, farmers, slaughterhouse workers, and laboratory personnel handling animal tissues
Normal Range
- Normal/Negative Result: <0.8 IU/mL or Negative by immunofluorescence assay (negative, no detectable IgM antibodies)
- Units of Measurement: International Units per milliliter (IU/mL) or reported as Positive/Negative/Equivocal
- Positive Result Cutoff: ≥0.8 IU/mL or Positive (indicates presence of IgM antibodies to Coxiella burnetii Phase II)
- Equivocal Range: 0.6-0.8 IU/mL (borderline result; repeat testing may be recommended in 7-10 days)
- Interpretation Summary: Negative indicates no current acute Q fever infection; Positive indicates recent or acute Coxiella burnetii infection; Equivocal requires clinical correlation and repeat testing
Interpretation
- Positive IgM Antibody Result: Indicates acute or recent Coxiella burnetii infection (Q fever); IgM is the first antibody to appear and typically peaks at 3-8 weeks then gradually declines over months; suggests active or recent infection within past 3-4 months
- Negative IgM Antibody Result: No acute infection detected; may indicate absence of Q fever infection, remote past infection (chronic Q fever), or early infection before IgM antibodies develop (window period)
- Clinical Correlation with IgG Antibodies: IgM presence without IgG suggests acute infection; IgM and IgG co-existence suggests early convalescence; IgG alone may indicate past or chronic infection
- Phase II vs Phase I Antigens: Acute Q fever typically shows IgM and IgG against Phase II antigen; chronic Q fever shows high IgG titers against Phase I antigen; IgM testing specifically targets Phase II response
- Factors Affecting Test Results: Timing of sample collection (IgM appears 3-5 days post-symptom onset), immunocompromised status may affect antibody production, previous infections or vaccinations may influence results, Cross-reactivity with other Coxiella species is possible
- Clinical Significance: Positive result is diagnostic for acute Q fever in appropriate clinical context; result combined with symptoms, exposure history, and imaging findings (chest X-ray) establishes diagnosis; negative result does not exclude Q fever if obtained too early in disease course
- Serial Testing Interpretation: Rising IgM titers indicate progressive acute infection; declining IgM with rising IgG suggests convalescent phase; persistently negative IgM with positive IgG suggests resolved past infection
Associated Organs
- Primary Organ System: Respiratory system (lungs) - Q fever commonly presents as atypical pneumonia; also affects hepatic system (liver) causing hepatitis
- Commonly Associated Conditions - Acute Q Fever: Atypical pneumonia (most common presentation), Acute hepatitis with elevated liver enzymes, Fever of unknown origin, Myocarditis, Pericarditis, Meningoencephalitis, Guillain-Barré syndrome
- Chronic Q Fever Complications: Endocarditis (frequently on pre-existing valvular disease), Vasculitis, Osteomyelitis, Chronic hepatitis, Chronic fatigue syndrome
- Secondary Organ Involvement: Central nervous system (CNS) complications including meningitis, encephalitis, and neuritis; Cardiovascular system with myocarditis and pericarditis; Renal involvement with glomerulonephritis possible
- High-Risk Patients for Severe Disease: Pregnant women (risk of miscarriage and poor fetal outcomes), Patients with valvular heart disease, Immunocompromised individuals, Chronic kidney disease patients on dialysis, Heart transplant recipients
- Potential Complications of Untreated Infection: Progression to chronic Q fever with serious complications, Acute respiratory distress syndrome (ARDS), Multi-organ failure, Sepsis, Death if untreated (mortality 1-2% in acute untreated Q fever)
Follow-up Tests
- Coxiella Burnetii IgG Antibody Serum: Recommended to confirm acute Q fever (IgM+IgG positive) and monitor progression to convalescence phase; IgG appears approximately 1-2 weeks after IgM and remains elevated for years
- Repeat IgM Testing: Recommended 7-10 days after initial equivocal result or if initial test performed during window period; serial titers can assess disease progression with rising titers indicating active infection
- Chest X-ray: Essential imaging to evaluate for pneumonia (segmental or lobar consolidation) and rule out other respiratory pathology; helps correlate with clinical presentation
- Liver Function Tests (LFTs): AST, ALT, alkaline phosphatase, bilirubin to detect hepatitis; Q fever commonly causes mild hepatic involvement with elevated transaminases
- Complete Blood Count (CBC): Assess for anemia, thrombocytopenia, and leukopenia which may occur with Q fever; helpful in monitoring disease severity
- Echocardiography: Recommended if endocarditis is suspected (murmur on examination, persistent fever despite antibiotics); essential screening in patients with valvular disease or prosthetic heart valves
- Blood Cultures: Usually negative (Coxiella burnetii rarely isolated), but obtained to rule out other bacterial infections; may be positive in chronic Q fever with endocarditis
- PCR Testing for Coxiella Burnetii: Molecular testing can detect bacterial DNA in blood; useful for early diagnosis before antibodies develop; may be ordered in specialized centers
- Monitoring Frequency: Acute Q fever: clinical and laboratory monitoring during treatment; follow-up serology 6-12 weeks after symptom onset to confirm diagnosis; chronic Q fever requires long-term antibiotic therapy with repeat serology every 3-6 months
- Related Complementary Tests: Rickettsial serology (Rocky Mountain spotted fever), Leptospira serology, Brucella serology, Bartonella serology (to rule out similar rickettsioses)
Fasting Required?
- Fasting Requirement: No - Fasting is NOT required for this test
- Sample Collection Type: Serum blood sample obtained via venipuncture; patient can eat and drink normally before blood draw
- Pre-Test Instructions: No special preparation required; standard blood draw precautions apply; inform phlebotomist of any recent infections or illnesses
- Medications: No medications need to be avoided before this test; continue taking all prescribed medications including antibiotics if already initiated for Q fever treatment
- Specimen Handling: Blood collected in serum separator tube (SST) without anticoagulant; specimen allowed to clot for 30 minutes then centrifuged; serum stored at room temperature or refrigerated (4°C) until testing
- Timing Considerations: Optimal timing for IgM detection is 3-5 days after symptom onset through approximately 2-3 months; early collection (within first 2-3 days) may yield false negative results
- Activity Restrictions: No activity restrictions before testing; patients should be well-hydrated for easier venipuncture; avoid strenuous exercise immediately after blood draw
- Results Timing: Results typically available within 24-48 hours; immunofluorescence assay requires manual microscopy so turnaround may vary; ELISA methods may be faster (24 hours)

How our test process works!