What to explain
Tell the clinician exactly what exposure happened and what symptoms followed.
I would like to discuss whether cat-scratch disease, another Bartonella infection, or another health problem could be contributing to my symptoms. Could we review any scratch, bite, flea exposure, swollen glands, fever, eye symptoms, and original test results, then decide whether more testing would change my care?
Questions to take in
Ask whether Bartonella testing is needed and what each result could change.
- Does my exposure and illness fit typical cat-scratch disease, another Bartonella infection, or a more likely condition?
- Do I need a Bartonella test, or are the exposure, examination, and symptoms enough to choose observation or treatment?
- If antibodies are tested, which species, IgG or IgM, titer, method, and repeat timing will matter?
- If PCR is useful, which specimen should be tested and what would a negative blood result fail to exclude?
- Do my eye, neurological, heart, liver, spleen, bone, or immune findings require imaging, tissue testing, or specialist review?
- Does separate evidence justify testing for Lyme disease, Babesia, Q fever, another infection, or a noninfectious cause?
- Could a positive result reflect past infection or cross-reaction, and what finding would establish that current illness needs treatment?
- Who will review the results, what symptoms require urgent help, and when should I return if symptoms persist?
Bartonella tests and general medical checks your clinician may consider
What each available test can and cannot show.
Testing depends on exposure, symptoms, exam, immune health, sample type, and suspected Bartonella species. Typical cat-scratch disease often doesn't need lab confirmation.
Bartonella IgG/IgM Antibodies
Bartonella IgG and IgM antibodies can help when the illness and exposure fit. Antibodies can cross-react, may not identify the exact species, and can remain positive for years.
Read the test guideBartonella PCR
PCR looks for Bartonella DNA in the submitted specimen. Blood PCR can miss infection, so the report must show the specimen and the clinical reason for testing.
Read the test guideCBC + CMP Blood Test Bundle
CBC checks red cells, white cells, and platelets. CMP checks glucose, electrolytes, proteins, liver markers, and kidney markers. Abnormal results may show another problem but do not diagnose Bartonella.
Read the test guideESR Blood Test
ESR can rise with inflammation, infection, autoimmune illness, anemia, age, pregnancy, and other conditions. A normal or high result does not settle the Bartonella question.
Read the test guidehs-CRP
hs-CRP measures one inflammation marker. Infection, injury, chronic illness, smoking, body size, and other factors can change it. It is not a Bartonella test.
Read the test guideBefore the appointment
Take the exposure dates, original results, medicines, and a short symptom record.
The date and location of each cat scratch, bite, lick on broken skin, flea exposure, body-louse exposure, animal contact, or relevant travel.
Dates for the first bump, fever, tender swollen gland, rash, eye symptom, headache, confusion, bone pain, chest symptom, and brain fog.
Clear photos of the actual scratch, bite, bump, swollen area, or other visible change. Add the date and body location.
A full medicine and supplement list, including antibiotics taken before testing, immune-suppressing medicines, recent changes, and any side effects.
Conditions or treatment that weaken the immune system, heart-valve disease, implanted heart material, recent dental or medical procedures, and prior serious infections.
Mention recent travel, unstable or crowded housing, body lice, cat fleas, animal rescue or veterinary work, and any separate tick exposure.
Two examples of daily problems, such as losing steps at work, forgetting medicine, becoming unsafe while driving, or needing help with school tasks.
For each test result, include the Bartonella species, IgG or IgM, titer or index, test method, sample type, lab reference range, collection date, ordering clinician, and any antibiotics taken beforehand.
How the doctor assesses this
Details that make a Bartonella assessment more useful
- A cat or kitten scratched or bit you, licked broken skin, or had fleas. A bump, fever, or tender swollen gland appeared afterward.
- You have long-lasting fever, eye inflammation, liver or spleen findings, bone pain, nervous-system symptoms, or possible heart-valve infection.
- You have a weakened immune system, body-louse exposure, relevant travel, or another exposure that could involve a different Bartonella species.
Reasons to check sleep, medicines, anemia, thyroid, migraine, and other infections too
- You have no cat, flea, body-louse, or travel exposure that fits, and no fever, swollen gland, scratch-site bump, eye or heart finding, or other sign of Bartonella illness.
- The only evidence is an online symptom list, a skin line, or a reaction to treatment, with no matching illness, exam finding, or usable lab result.
- The only lab evidence is one old positive IgG (antibody) result. Your current symptoms began at another time, and your records better support a different cause.
- Brain fog changes with sleep loss, standing, migraine, meals, a medicine dose, alcohol, cannabis, anemia, thyroid disease, or another condition that has direct evidence.
- Symptoms continue after a diagnosed Bartonella illness has resolved and the clinician finds a separate untreated cause.
What to understand before choosing care
Information the clinician uses to choose examination, testing, imaging, referral, treatment, or observation.
- Give the exact exposure and symptom dates. Cat-scratch disease usually causes a bump, fever, or tender swollen gland, not brain fog alone.
- Bring the complete laboratory report. A positive antibody result can persist for years and does not establish current infection.
- Temporary worsening after medicine or supplements doesn't prove infection or prove that treatment is working.
- Ticks aren't known to spread Bartonella. Discuss Lyme disease or other tick-borne testing only when their own exposure and symptoms justify it.
- Ask who will interpret the result, whether you need an infectious-disease, eye, heart, or neurological review, and what would change treatment.
What the research found
What current guidance and research say about diagnosis, testing, and uncommon complications.
CDC guidance updated in March 2026 says doctors can diagnose most typical cat-scratch disease from symptoms, exam, and cat exposure. People generally don't need lab tests unless illness is severe or unusual.
CDC says Bartonella antibody tests may react to other germs, mix up species, and stay positive for years after effective treatment.
CDC says blood PCR sensitivity is not optimal. It also advises holding a suspected Bartonella culture for at least 21 days because the bacterium grows slowly.
A US claims study identified 14,824 cat-scratch disease cases. It counted 224, or 1.5%, as unusual (atypical) cases, and 13.8% of those involved the nervous system.
A 2025 diagnostic review found that culture, antibody tests, and PCR still face sensitivity, cross-reaction, and standardization problems. No single test can replace a compatible clinical assessment.
How age, sex, pregnancy, and immune health change the medical review.
CDC says cat-scratch disease occurs more often in children under age 15, although any age can be affected. A child with fever and tender swollen glands after cat exposure needs pediatric review.
Adults need the same exact exposure and symptom dates. There is no separate Bartonella antibody cutoff for men and women; the species, method, titer, timing, and clinical findings matter more.
People with weakened immune systems have a higher risk of severe illness. Report HIV, cancer treatment, transplant medicine, steroids, immune-suppressing drugs, and other immune conditions promptly.
Report pregnancy, recent birth, or breastfeeding before anyone chooses antibiotics, scans, or tests. During pregnancy, have a clinician treat any suspected infection.
Older adults may have heart-valve disease, immune problems, medicine effects, and other causes of confusion or fever. New confusion, fainting, chest symptoms, or marked weakness needs direct assessment.
If the answer is no
If your doctor will not order a broad Bartonella panel
A broad Bartonella panel cannot prove that the infection caused long-lasting, general symptoms. The CDC says common cat-scratch disease can often be diagnosed from the illness and a matching cat exposure. Tests are more useful in severe, unusual, or unclear cases. Antibody tests can react to related germs or stay positive after treatment. A blood PCR test can also miss an infection.
What changes the answer
- Bring the exposure and symptom dates. A recent cat scratch followed by swollen lymph nodes is different from years of fatigue with no matching exposure. Include animal, lice, and travel details.
- Ask which Bartonella illness is suspected. Cat-scratch disease, trench fever, and a Bartonella heart infection need different tests and care.
- Ask what a positive result would mean. Bartonella antibodies can react to related species and stay positive after treatment. The result must fit your exposure and illness.
- Name signs of a severe or unusual illness. Eye, heart, liver, or nerve problems may support an infection specialist review or focused testing.
United States, United Kingdom, and Australia
Where to seek Bartonella assessment.
US United States
Book primary care or pediatric care. Bring the scratch or bite date, symptoms, immune conditions, medicines, photos, and original results. Ask whether you need testing or specialist review.
- Book primary care or pediatric care for fever, a tender swollen gland, or a scratch-site bump after cat exposure.
- Severe, unusual, immune-related, eye, neurological, or heart symptoms may need specialist testing.
- Use emergency care for sudden confusion, seizure, new vision loss, stroke symptoms, fainting, severe breathing trouble, or rapidly worsening illness.
UK United Kingdom
Book a GP appointment. Bring the exposure, travel, symptom dates, immune conditions, medicines, photos, and original results. Ask whether you need UKHSA testing or referral.
- See your GP if fever, fatigue, swollen glands, skin lesions, or a similar illness starts after an exposure.
- UKHSA offers Bartonella antibody and PCR tests through the Rare and Imported Pathogens Laboratory. Requests need your medical and travel history.
- Use A&E for sudden confusion, seizure, new vision loss, stroke symptoms, fainting, severe breathing trouble, or rapidly worsening illness.
AU Australia
Book a GP appointment. Bring the exposure and symptom dates, immune conditions, medicines, photos, and original results. Ask whether you need testing or specialist referral.
- Healthdirect advises medical care after an animal bite or scratch, especially when the skin is broken or signs of infection appear.
- Tell the GP about fever, swollen glands, the scratch or bite date, immune conditions, medicines, and every complete Bartonella report.
- Call triple zero for sudden confusion, seizure, stroke symptoms, severe breathing trouble, fainting, or another life-threatening symptom.
Safety
Show how it affects daily life
- What shows up with the brain fog: fever, swollen glands, eye symptoms, headache, pain.
- One daily task that failed: a forgotten work step, a missed medicine, unsafe driving.
- Measure or photograph only what you can safely record. Do not press, drain, cut, or repeatedly handle a swollen lymph node or skin lesion.
- Do not start leftover antibiotics, stop prescribed medicine, provoke symptoms, or use a treatment reaction as a home diagnostic test.
- At follow-up, compare exposure dates, examination findings, laboratory details, treatment, and daily function. One symptom score alone isn't enough.
Source checked
Sources behind this handout.
- 01
Centers for Disease Control and Prevention. Clinical Overview of Cat Scratch Disease. Updated March 23, 2026.
Source - 02
Centers for Disease Control and Prevention. About Cat Scratch Disease. Updated March 23, 2026.
Source - 03
Centers for Disease Control and Prevention. Testing and Diagnosis for Lyme Disease. Notes that Bartonella transmission by ticks is not established.
Source - 04
UK Health Security Agency. Bartonella: diagnostic services. Updated May 22, 2025.
Source - 05
Cardoso TL et al. Bartonella henselae: A challenging diagnosis with a bright future. Journal of Microbiological Methods. 2025. PMID: 41109599.
Source - 06
Nawrocki CC et al. Atypical Manifestations of Cat-Scratch Disease, United States, 2005-2014. Emerging Infectious Diseases. 2020. PMID: 32568056.
Source