[Infection and angiomatous cutaneous lesions]

The occurrence of angiomatous cutaneous lesions in the presence of an infective process is not a frequent phenomenon. Most infectious diseases are associated with an exanthematous reaction. The combination of an infective illness and angiomatous lesions is seen essentially in the bartonelloses and in Kaposi's disease. Bartonelloses: group of infections due to alpha-proteobacteria such as Bartonella. Bartonella bacilliformis (BB), is the causal agent of Carrion's disease, the chronic cutaneous form of which (verruga peruana), in which the vector is an arthropod of the Lutzomyia species found in South America, presents superficial and deep angiomatous cutaneous nodules. Spontaneous regression occurs in a few months or years. Bartonella henselae (BH) and Bartonella quintana (BQ), are the causal agents of bacillary angiomatosis (BA), described in 1983, in which angiomatous papules or nodules with an appearance like botryomycomas, are associated with visceral lesions. The characteristic histological features (with the demonstration or the bacilli by Warthin-Starry stain) together with culture of the bacterium in various tissues (including the blood) are diagnostic. BA occurs most commonly, but not exclusively, in patients with HIV infection. Furthermore, BH is responsible for cat scratch disease while BQ causes trench fever. The reservoir of BH is the cat. The bartonella produce angiogenic factors responsible for the neovascularisation seen in angiomatous lesions. The differential diagnosis is between botryomycomas and Kaposi's disease. Numerous antibiotics are effective against botryomycomas, particularly chloramphenicol and penicillin for BB and macrolides, cyclins and fluoroquinolones for BH and BQ. Kaposi's disease (KD): whether classical, endemic or epidemic (due to HIV infection) is characterised by cutaneous and visceral angiomatous lesions: these are associated with multifocal tumorous proliferations (of endothelial and fusiform cells) affected by angiogenic growth factors (PDGF, FGF, IL6, alphaTGF, HIVtat, androgens) and strongly linked to the lymphocytic and endothelial tropism of a gamma herpes virus (HHV8, Chang and Moore 1994). HHV8 infection, probably sexually transmitted, is also the cause of lymphomas occurring in cavities and of Castleman's disease. The course of KD is very variable: from the indolent form in elderly HIV-ve patients, to the explosive forms in the immunodepressed (particularly in HIV+ve patients.