Rare, disseminated Kaposi sarcoma in advanced HIV with high-burden pulmonary and skeletal involvement

We describe the case of a 30-year-old man who presented to our institution with hypoxia and widespread pulmonary infiltrates managed initially as COVID-19 before receiving a new diagnosis of HIV-associated Kaposi sarcoma (KS) with widespread pulmonary and skeletal involvement. Initial differential diagnoses included Pneumocystis jirovecii pneumonia, disseminated mycobacterial infection and bacillary angiomatosis. A bone marrow biopsy showed heavy infiltration by spindle cells, staining strongly positive for human herpes virus-8 (HHV-8) and CD34, suggesting symptomatic, disseminated KS as the unifying diagnosis. The patient commenced cytotoxic therapy with weekly paclitaxel, with a clinical and radiological response. To our knowledge, this case is among the most severe described in the literature, which we discuss, along with how COVID-19 initially hindered developing a therapeutic allegiance with the patient.

Giant bacillary angiomatosis

No abstract available.

Bartonella henselae Persistence within Mesenchymal Stromal Cells Enhances Endothelial Cells Activation and Infectability Amplifying the Angiogenic Process.

Some bacterial pathogens can manipulate the angiogenic response, suppressing or inducing it for their own ends. In humans, B. henselae is associated with cat-scratch disease and vasculoproliferative disorders such as bacillary angiomatosis and bacillary peliosis. Although endothelial cells (ECs) support the pathogenesis of Bartonella , the mechanisms by which Bartonella induces EC activation are not completely clear, as well as the possible contribution of other cells recruited at the site of infection. Mesenchymal stromal cells (MSCs) are endowed with angiogenic potential and play a dual role in infections exerting antimicrobial properties but also acting as a shelter for pathogens. Here we delved into the role of MSCs as reservoir of Bartonella and modulator of EC functions. B. henselae readily infected MSCs and survived in perinuclear bound vacuoles for up to 8 days. Infection enhanced MSC proliferation and the expression of EGFR, TLR2 and NOD1, proteins that are involved in bacterial internalization and cytokine production. Secretome analysis revealed that infected MSCs secreted higher levels of the proangiogenic factors VEGF, FGF-7, MMP-9, PIGF, serpin E1, TSP-1, uPA, IL-6, PDGF-D, CCL5 and CXCL8. Supernatants from B. henselae -infected MSCs increased the susceptibility of ECs to B. henselae infection and enhanced EC proliferation, invasion and reorganization in tube-like structures. Altogether, these results candidate MSCs as a still underestimated niche for B. henselae persistent infection and reveal a MSC-EC crosstalk that may contribute to exacerbate bacterial-induced angiogenesis and granuloma formation.

Pulse Treatment Using Azithromycin in HIV/AIDS-Associated Solitary Tumor-Like Bacillary Angiomatosis

With the advent of the HIV/AIDS pandemic within the South Saharan region, clinicians are faced with accentuated clinical presentations of previously well-known diseases. Bacillary angiomatosis is no exception to this rule. Bacillary angiomatosis is a cutaneous and systemic bacterial infection caused by gram-negative Bartonella species. We report a case of an immunocompromised 44 years old female patient who presented with a solitary tumor-like bacillary angiomatosis that was treated successfully with azithromycin in a bi-weekly pulsed dosing regimen. This patient had a considerably large (12 x 10cm’s) single lesion of the disease. The case highlights the potential that immunosuppressed patients are not only at risk of disseminated disease, but also of developing severe localized disease. Furthermore, Azithromycin pulse treatment may offer a convenient alternative as there is still no clear consensus regarding treatment protocol for using azithromycin in the treatment of cutaneous bartonellosis.