Skip to content

Ricksfiggmsmtser

Published: August 9, 2026Updated: August 17, 2026

A blood test that detects IgG antibodies against Rickettsia bacteria to help diagnose spotted fever infections.

Quick summary

{"A simple blood test that checks for IgG antibodies against Rickettsia bacteria","Helps diagnose Rocky Mountain spotted fever and other related infections","Sample is collected from a vein in your arm","Results can indicate current or past infection","Early diagnosis is important for prompt antibiotic treatment"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
110689-7
Short code
RICK-IgG
Synonyms
Rick SF IgG Msmt Ser
Category
cardiac
Sample
serum
Container
Serum separator tube (SST) or plain red top tube
Units
N/A
Ref low
64
Ref high
128
Critical range
— – 10000 N/A
Fasting
false
Population
adult
Sex
all
Age range
≥ 0 years
Method
Immunofluorescence Assay (IFA) or Enzyme-Linked Immunosorbent Assay (ELISA)
CPT
86757
SNOMED
413458004
Specimen volume
1.0 to 2.0 mL of serum
Stability
Room temperature: 24 hours; Refrigerated (2-8°C): 7 days; Frozen (-20°C or below): 30 days. Avoid repeated freeze-thaw cycles.
Hemolysis max
50
Lipemia max
300
Icterus max
20
TAT
24–72 hours
Order
routine

What is this test?

The Rickettsia Spotted Fever Group IgG Antibody Test is a blood test that looks for IgG antibodies in your serum. IgG antibodies are proteins produced by your immune system in response to an infection. This test specifically checks for antibodies against Rickettsia bacteria that cause spotted fever diseases, including Rocky Mountain spotted fever, Mediterranean spotted fever, and other related infections. These bacteria are typically transmitted through tick bites.

Reference range

Negative: <1:64 titer; Indeterminate: 1:64 to 1:128 titer; Positive: >=1:128 titer (titers may vary by laboratory)N/A

Specimen: serum

No special preparation required. Fasting not necessary. Inform laboratory of recent infections, antibiotic therapy, or immunization history.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Frequently asked questions

Why do I need this test?
Your doctor may order this test if you have symptoms such as fever, headache, rash (typically starting on wrists and ankles and spreading to the trunk), muscle pain, or if you have a known or suspected tick bite. These symptoms are common in spotted fever infections.
How is the test performed?
A healthcare professional will draw a small blood sample from a vein in your arm. The blood will be sent to a laboratory where it will be tested for the presence of IgG antibodies against Rickettsia bacteria.
What do the results mean?
A positive result indicates that you have or have had an infection with Rickettsia bacteria that cause spotted fever. A negative result may mean you do not have the infection, or it may be too early in the infection to detect antibodies. Your doctor will interpret the results in combination with your symptoms and other test findings.
Is any special preparation needed?
No special preparation is typically required for this test. You can eat and drink normally before the blood draw. However, always follow any specific instructions your healthcare provider gives you.
How long does it take to get results?
Results are usually available within a few days to a week, depending on the laboratory. Your healthcare provider will contact you with the results or discuss them at your follow-up appointment.
  1. 1
    Centers for Disease Control and Prevention (CDC) - Rocky Mountain Spotted FeverSource
  2. 2
    Mayo Clinic - Rocky Mountain Spotted FeverSource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy