Cat-scratch disease
Cat-scratch disease is due to an infection by B. henselae and manifests as gradual regional lymph nodes enlargement (axilla, groin, neck) which may last 2–3 months or longer and a distal scratch and/or red-brown skin papule (not always seen at the time of the disease). The enlarged lymph node is painful and tender. The lymph nodes may suppurate, some patients may remain afebrile or asymptomatic. Other presentations include fever (particularly in children), Parinauds oculoglandular syndrome, encephalopathy, and neuroretinitis.B. henselae can be associated with bacteremia, bacillary angiomatosis, and peliosis hepatis in HIV patients, and bacteremia and endocarditis in immunocompetent and immunocompromised patients. Symptoms may include fatigue, headaches, fever, memory loss, disorientation, insomnia, and loss of coordination. The bacteria block the normal immune response by suppressing the NF-κB apoptosis pathway. Disease progression may be accelerated if the host is subsequently infected by an immune-suppressing virus such as Epstein Barr virus. Bacillary angiomatosis
B. henselae and B. quintana can cause bacillary angiomatosis, a vascular proliferative disease involving mainly the skin, and other organs. The disease was first described in human immunodeficiency virus (HIV) patients and organ transplant recipients. Severe, progressive and disseminated disease may occur in HIV  patients. Differential diagnoses include Kaposis sarcoma, pyogenic granuloma, hemangioma, verruga peruana, and subcutaneous tumors. Lesions can affect bone marrow, liver, spleen, or lymph nodes. Peliosis hepatis
B. henselae is the etiologic agent for peliosis hepatis, which is defined as a vascular proliferation of sinusoid hepatic capillaries resulting in blood-filled spaces in the liver in HIV patients and organ transplant recipients.
are fastidious, slow-growing bacteria that are difficult to grow using traditional solid agar plate culture methods due to complex nutritional requirements and potentially a low number of circulating bacteria. This conventional method of culturing Bartonella spp. from blood inoculates plated directly onto solid agar plates requires an extended incubation period of 21 days due to the slow growth rate. Enrichment Culture
Bartonella growth rates improve when cultured in an enrichment inoculation step in a liquid insect-based medium  such as Bartonella Alphaproteobacteria Growth Medium (BAPGM)  or Schneiders Drosophila-based insect powder medium. Several studies have optimized the growing conditions of Bartonella spp. cultures in these liquid media, with no change in bacterial protein expressions or host interactions in vitro. Insect-based liquid media supports the growth and co-culturing of at least seven Bartonella species, reduces bacterial culturing time and facilitates PCR detection and isolation of Bartonella spp. from animal and patient samples. Research shows that DNA may be detected following direct extraction from blood samples and become negative following enrichment culture, thus PCR is recommended after direct sample extraction and also following incubation in enrichment culture. Several studies have successfully optimized sensitivity and specificity by using PCR amplification (pre-enrichment PCR) and enrichment culturing of blood draw samples, followed by PCR (post-enrichment PCR) and DNA sequence identification. Serial Testing
As Bartonella spp. infect at low levels and cycle between blood and tissues, multiple blood draws over time may be necessary to detect infection. Treatment
Treatment of infections caused by Bartonella species include:
Some authorities recommend the use of azithromycin.