Case study
A 43-year-old male presented with a two-week history of mucocutaneous lesions in addition to anorexia and weight loss. His medical history included HIV infection with previous non-adherence to antiretroviral therapy and loss to follow-up. On inspection, widespread, polymorphic skin lesions were observed, including a nodule on the arm resembling a dermatofibroma (Fig. 1), subcutaneous nodules on the forehead (Fig. 2) and lower back, scattered papules on the limbs, an abscess-like lesion on the back, and an ulcer of the hard palate. CD4 lymphocyte count was 41 cells/μL. Histopathological examination of sections from a skin biopsy (Fig. 3) demonstrated proliferation of capillary sized vessels with epitheloid endothelial cells, interstitial mixed inflammatory cells, and extracellular granular amphophilic material that stained positive with Warthin-Starry stain. Electron microscopy performed on tissue from the skin biopsy revealed bacilli with characteristic trilaminar cell membranes (Fig. 4). Skin tissue cultures were negative, but amplification and sequencing of the 16s rRNA gene identified Bartonella quintana. The patient was treated with doxycycline 100 mg twice daily with prompt clinical improvement. Later, antiretrovirals were re-introduced with adherence counselling. Bacillary angiomatosis is a potentially fatal disease in immunocompromised hosts, caused by infection with B. henselae or B. quintana, transmitted by the cat flea and human body louse, respectively. It is characterized by mucocutaneous and, less commonly, visceral, or bony lesions. Polymorphic skin lesions may be observed in a single patient, as in the current case. Demonstration of bacilli with Warthin-Starry stain is characteristic, but confirmation of the Bartonella species by culture or PCR is pathognomonic. Electron microscopy is a diagnostic aid. Treatment includes tetracyclines or macrolide antibiotics, often requiring protracted therapy depending on immune reconstitution.
Fig. 1.
A nodule on the patient’s forearm resembling a dermatofibroma.
Fig. 2.
Subcutaneous nodules on the patient’s forehead.
Fig. 3.
Hemotoxylin and Eosin stain demonstrating masses of extracellular granular amphophilic material (arrows).
Fig. 4.
Electron microscopy image of Bartonellae appearing as pleomorphic rods. Note the trilaminar cell membranes (arrow).
Contributorship and conflict of interest statement
The authors declare no conflicts of interest.
All authors have contributed significantly to the work and have seen and approved the manuscript being submitted.
The authors confirm that the material within this manuscript represents original work, and has or will not be submitted for publication elsewhere as long as it is under consideration by ID cases.
Written informed consent for this manuscript and the photos therein was obtained from the patient. The corresponding author has retained a copy of the informed consent document.