Detection of Bartonella vinsonii subsp. berkhoffii in an HIV patient using metagenomic Next-Generation Sequencing

Bartonella species are fastidious, aerobic bacteria that are transmitted by blood-sucking arthropods. Bartonella spp. are responsible for cat scratch disease, Carrion's disease, bacillary angiomatosis and trench fever. On the other hand, Bartonella vinsonii is rarely reported in the literature and there exist a few reports of systemic infection caused by Bartonella vinsonii in patients with acquired immunodeficiency syndrome. A 31-year-old male (diagnosed with AIDS six years ago) had persistent fever and ulceration in the right knee. The elevated levels of inflammatory markers suggested an infectious aetiology. Despite the negative findings of blood culture, metagenomic Next-Generation Sequencing of plasma detected Bartonella vinsonii. The polymerase chain reaction of whole blood and Sanger sequencing confirmed the mNGS findings. Immunohistochemical staining had later suggested bacillary angiomatosis, which was consistent with Bartonella infection. Following antibiotic treatment, the ulcers subsided significantly, but a high fever persisted. The patient died due to sudden respiratory failure.