Bartonellosis: Causes, Symptoms, Diagnosis, and Treatment

What is Bartonellosis (Cat Scratch Disease)?

Bartonellosis, commonly known as Cat Scratch Disease (CSD), is a bacterial infection caused by Bartonella henselae. It is primarily transmitted to humans through scratches, bites, or licks from infected cats, particularly kittens.

While most cases are mild, the infection can cause serious complications in people with weakened immune systems, such as those with HIV/AIDS, cancer, or organ transplants.

What Causes Bartonellosis?

Bartonellosis is caused by Bartonella henselae, a bacteria found in the saliva and claws of infected cats. The bacteria are transmitted to humans through:

• Cat scratches or bites (especially from kittens)
• Licking of open wounds or broken skin by an infected cat
• Flea bites (fleas spread the bacteria between cats, but not directly to humans)

Risk Factors:

• Owning or handling cats, particularly kittens
• Scratches or bites from stray or outdoor cats
• Weakened immune system (HIV/AIDS, chemotherapy, diabetes)
• Flea infestations (increase bacterial spread among cats)

What Are the Symptoms of Bartonellosis?

Symptoms usually appear 3 to 14 days after exposure and range from mild to severe, depending on the person’s immune status.

Common Symptoms:

• Swollen, painful lymph nodes (near the scratch or bite site)
• Red, raised bump or blister at the scratch site
• Fatigue and weakness
• Low-grade fever (100–102°F or 37.7–38.8°C)
• Headache and body aches

Severe Symptoms (Rare, but Serious):

• High fever and chills
• Severe swelling of lymph nodes with pus drainage
• Loss of appetite and weight loss
• Neurological issues (seizures, confusion, or vision problems)
• Endocarditis (heart valve infection in rare cases)

Complications in Immunocompromised Individuals:

• Bacillary Angiomatosis – Skin and blood vessel growths, often seen in HIV/AIDS patients.
• Peliosis Hepatis – Blood-filled cysts in the liver and spleen.
• Ocular Bartonellosis – Eye infections leading to vision problems.

How is Bartonellosis Diagnosed?

Doctors diagnose Bartonellosis based on medical history, symptoms, and lab tests.

Diagnostic Tests:

• Physical Examination – Checks for swollen lymph nodes and scratch marks.
• Blood Tests – Detects Bartonella antibodies or bacterial DNA.
• Polymerase Chain Reaction (PCR) – Identifies bacterial genetic material.
• Lymph Node Biopsy – Performed in severe or unclear cases.

What is the Treatment for Bartonellosis?

Most healthy individuals recover without treatment within 2 to 4 months. However, antibiotics are recommended for severe or prolonged cases.

Medications Used:

• Azithromycin – First-line antibiotic for faster recovery.
• Doxycycline + Rifampin – For severe or systemic infections.
• Erythromycin or Ciprofloxacin – Alternative antibiotics.

Supportive Care:

• Pain relievers (Ibuprofen or Acetaminophen) – Helps with fever and swelling.
• Warm compresses – Reduces swollen lymph nodes.
• Rest and hydration – Aids recovery.

Complications of Bartonellosis?

Although rare, untreated Bartonellosis can lead to serious complications, especially in people with weak immune systems.

Potential Complications:

• Chronic lymph node swelling (lasting months)
• Neurological problems (encephalopathy, seizures)
• Eye infections (neuroretinitis, optic nerve swelling)
• Heart infections (endocarditis, myocarditis)
• Liver and spleen cysts (peliosis hepatis)

Prevention of Bartonellosis?

To reduce the risk of infection, follow these preventive measures:

• Avoid rough play with cats, especially kittens.
• Wash cat scratches or bites immediately with soap and water.
• Keep cats indoors to minimize exposure to fleas.
• Use flea control measures to prevent Bartonella transmission.
• Trim cat nails regularly to reduce scratching injuries.
• Do not allow cats to lick open wounds or broken skin.

When to See a Doctor?

Seek medical attention if you experience:

• Swollen lymph nodes lasting more than 2 weeks
• Severe fever, headaches, or fatigue
• Pus-draining lymph nodes
• Neurological symptoms (seizures, confusion, vision problems)
• Symptoms worsening despite treatment