Case reports: Bartonella associated with psychiatric symptoms


The Bartonella pathogen can be carried and transmitted by various animals and insects including fleas, flea feces, cat licks or scratches, ticks, lice, and biting flies. The infection has been associated with new-onset neurologic and psychiatric symptoms.

In their 2007 article, “Do Bartonella Infections Cause Agitation, Panic Disorder, and Treatment-Resistant Depression?” Schaller and colleagues describe 3 patients with acute psychiatric symptoms associated with Bartonella-like sign and symptoms.¹

Each of the patients was exposed to ticks or fleas and manifest symptoms consistent with Bartonella, i.e., an enlarged lymph node near an Ixodes tick bite and bacillary angiomatosis found only in Bartonella infections, according to the authors.

“… we have presented case studies of patients with new clear psychiatric morbidity, sudden agitation, panic attacks, and treatment-resistant depression, all possibly attributed to Bartonella.”

The patients were treated at an outpatient clinic for acute-onset personality changes including agitation, depression and panic attacks.

Interestingly, treatment with psychotropics was not effective in relieving their symptoms.

However, “After receiving antibiotic treatment for presumed Bartonella, [psychotropic] doses were reduced and all patients improved significantly, returning to their baseline mental health status,” the authors wrote.

In this article, we highlight 2 of those cases.

Case #1

A 41-year-old man had a complete personality change, according to his family, following a camping trip in North Carolina. The man developed a small, “aching” right-sided axillary lymph node and fever after the trip. He had removed 3 deer ticks from his leg and shoulder.

Five weeks later, he exhibited irritability, severe insomnia, rage and sensitivity to smells and sounds. He also reported having an “enlarged and very annoying” right-sided axillary lymph node which had been present since the trip.

Lyme disease testing was negative. However, clinicians suspected Bartonella, given his unilateral lymph node symptom and tick bite.

“A PCR test for 2 Bartonella species was negative, but positive for B henselae when repeated,” the authors wrote.

During the next 2 weeks, the patient developed serious agitation, panic attacks, and major depression.

“He was so agitated that during arguments with his spouse, he threw objects such as kitchen glasses, a baseball, and a chair into his home’s drywall.”

The patient was diagnosed with bipolar disorder, although he had no previous history of depression or mania. However, psychotropic medications did not relieve his symptoms.

“At this point, the patient still had a large tender unilateral lymph node, fatigue, and new papules under his right arm,” the authors wrote. “Various causes of persistent large unilateral lymph nodes with papules were felt to fit a diagnosis of Bartonella.”

An infectious disease clinician prescribed azithromycin and Rifampin for suspected Bartonella infection.

After 8 weeks of treatment, the patient’s lymph node complaints resolved. And, his psychiatric symptoms were reduced substantially.

“His personality is felt to be 90% of baseline, according to his spouse and closest friend.”

“We suggest this man’s psychiatric problems support a Bartonella presentation,” as he had a positive response to antibiotics targeting Bartonella and his psychiatric symptoms resolved almost simultaneously with the resolution of his enlarged lymph node.

Case #2

A medical student reported having a rash on her thighs consisting of 4 linear lines, which developed after she had adopted 2 young cats from a shelter. She also reported having several flea bites.

“The patient complained of new panic attacks, profound restlessness, and depression that began around the time of her new thigh rashes,” the authors wrote.

Treatment with psychotropic medications was not effective.

The patient’s nurse practitioner suspected Bartonella and prescribed a course of cefuroxime and azithromycin.

During the first week of treatment, the young woman became “increasingly sad, irritable, and hopeless, with increased panic attacks,” the authors wrote. Week 2, the symptoms had subsided slightly. By week 3, the rash had disappeared and by the 8th week, her depression and anxiety had improved substantially.

Six months later, some of the symptoms reappeared with “moderate return of inappropriate anger, excess interpersonal sensitivity, severe premenstrual dysphoric disorder, irritability, and sadness.”

The patient was retreated with rifampicin and cefdinir and improved somewhat.

The author’s point out that all of the patients initially required higher doses of psychotropic medications to function normally. However, following antibiotic treatment, doses were reduced or stopped entirely as Bartonella symptoms appeared to remit.


  1. Schaller JL, Burkland GA, Langhoff PJ. Do bartonella infections cause agitation, panic disorder, and treatment-resistant depression? MedGenMed. 2007 Sep 13;9(3):54. PMID: 18092060; PMCID: PMC2100128.

2 Replies to "Case reports: Bartonella associated with psychiatric symptoms"

  • Vito
    01/22/2024 (3:09 pm)

    Dr Cameron, I’m under the care of an LLMD in my area (Central New Jersey) for Lyme and Bartonella. I was on doxy and Clarithromycin for 4 1/2 months after catching the symptoms early (I’ve had Lyme several times before). I stopped taking the antibiotics after I got a terrible intestinal Candida infection that I couldn’t get rid of while on the antibiotics. After almost three weeks on Diflucan, I feel better. Is 4 1/2 months of antibiotics generally long enough to treat Bartonella? I’m reading between 4 and 6 months and I’m in that range. I ask because my LLMD – there aren’t a lot available in my area – feels that I should keep taking the antibiotics but the problems the problems they’re now causing are just as bad as the original infection.

    • Dr. Daniel Cameron
      01/22/2024 (5:58 pm)

      I have had patients who have benefited from treatment for other tick borne infections ie Lyme with Ceftin or Babesia with Malarone, I sometimes have used lower doses or single therapy. Finally, I have had to refer to rule out other issues.

Join the Lyme Conversation
(Note: comments are moderated. You will see your comment after it has been reviewed.)

Some html is OK