Porphyromonas gingivalis coinfects with KSHV in oral cavities of HIV+ patients and induces viral lytic reactivation

Kaposi's sarcoma-associated herpesvirus (KSHV) infection causes several human cancers, including Kaposi's sarcoma (KS), one of the most common AIDS-associated tumors. The involvement of the oral cavity represents one common clinical manifestation of AIDS-KS individuals with periodontal diseases and an oral carriage of a variety of pathogenic bacteria, including Porphyromonas gingivalis. In the current study, we report the clinical relevance of P. gingivalis and KSHV coinfection in the oral cavity of a cohort of HIV+ patients. Furthermore, we found that P. gingivalis conditioned medium or derived lipopolysaccharide effectively induced KSHV lytic reactivation from infected oral cells. This reactivation requires TLR4 as well as the activities of p38 and Jun N-terminal kinase- mitogen-activated protein kinase signaling pathways. Our findings reveal the mechanisms through which coinfected periodontal pathogens potentially promote oncogenic virus pathogenesis in the unique niche of immunocompromised patients.

Signatures of oral microbiome in HIV-infected individuals with oral Kaposi's sarcoma and cell-associated KSHV DNA

Infection by Kaposi’s sarcoma-associated herpesvirus (KSHV) is necessary for the development of Kaposi’s sarcoma (KS), which most often develops in HIV-infected individuals. KS frequently has oral manifestations and KSHV DNA can be detected in oral cells. Numerous types of cancer are associated with the alteration of microbiome including bacteria and virus. We hypothesize that oral bacterial microbiota affects or is affected by oral KS and the presence of oral cell-associated KSHV DNA. In this study, oral and blood specimens were collected from a cohort of HIV/KSHV-coinfected individuals all previously diagnosed with KS, and were classified as having oral KS with any oral cell-associated KSHV DNA status (O-KS, n = 9), no oral KS but with oral cell-associated KSHV DNA (O-KSHV, n = 10), or with neither oral KS nor oral cell-associated KSHV DNA (No KSHV, n = 10). We sequenced the hypervariable V1-V2 region of the 16S rRNA gene present in oral cell-associated DNA by next generation sequencing. The diversity, richness, relative abundance of operational taxonomic units (OTUs) and taxonomic composition of oral microbiota were analyzed and compared across the 3 studied groups. We found impoverishment of oral microbial diversity and enrichment of specific microbiota in O-KS individuals compared to O-KSHV or No KSHV individuals. These results suggest that HIV/KSHV coinfection and oral microbiota might impact one another and influence the development of oral KS.

Kaposi’s sarcoma (KS) is the most common cancer occurring in HIV-infected individuals worldwide, and often involves the mouth. While infection by Kaposi’s sarcoma-associated herpesvirus (KSHV) is necessary for the development of KS, other cofactors remain unclear. In this study, we evaluated the impact of oral bacterial microbiota on the development of oral KS and the presence of oral cell-associated KSHV DNA by studying a cohort of HIV/KSHV-coinfected individuals all previously diagnosed with KS, classified as having oral KS with any oral cell-associated KSHV DNA status (O-KS), no oral KS but with oral cell-associated KSHV DNA (O-KSHV), or with neither oral KS nor oral cell-associated KSHV DNA (No KSHV). We observed impoverishment of oral microbial diversity and enrichment of specific types of microbes in O-KS individuals compared to O-KSHV or No KSHV individuals. Hence, HIV/KSHV coinfection and oral microbiota might impact one another and influence the development of oral KS.

Electron Microscopy Reveals Fungal Cells Within Tumor Tissue from Two African Patients with AIDS-associated Kaposi Sarcoma

Electron microscopic investigation of biopsy materials from Kaposi sarcoma (KS) skin lesions of 2 African AIDS patients occasionally revealed fungal cells within the tumor tissue. The spherical cells were surrounded by a triple-layered cell wall and were not encapsulated. The ultrastructural characteristics of the cells resemble those of Candida albicans organisms. Neither patient showed clinical signs of a generalized fungal infection. The presence of Candida albicans in the KS tissue specimens seems to represent an early and asymptomatic stage of cutaneous candidiasis in the 2 severely immunocompromised AIDS patients.

Mycobacterial spindle cell pseudotumor of the appendix vermiformis in a patient with aids

Mycobacterial pseudotumor (MP) is a rare pathologic presentation of both Mycobacterium tuberculosis and non-tuberculous mycobacterial disease, hitherto reported to occur only in immunosuppressed patients with or without human immunodeficiency virus infection. This lesion shares close pathologic resemblance to certain mesenchymal neoplasms, particularly Kaposi's sarcoma (KS), from which it must be properly differentiated due to distinct prognosis and therapy. We report a case of MP obliterating the lumen of the appendix vermiformis in a 34-year-old patient who died of complications of AIDS at our hospital in Rio de Janeiro. A total of 24 cases of MP (including our patient) have been described in the literature. MP has been found especially in lymph nodes, but extranodal lesions have been described in the skin, spleen, lung, bone marrow, brain and, in our patient, the appendix vermiformis. We offer a review of the other 23 published case reports of MP in both HIV-infected and uninfected patients and discuss the pathologic features that differentiate MP from KS.

Unidentified bacterial microorganisms entrapped within blood capillary spaces of tissue from different epidemiological types of Kaposi's sarcoma

Tissue specimens of different epidemiological types of Kaposis sarcoma (KS) from various geographical regions were investigated by transmission electron microscopy. Freshly fixed KS biopsies originated from 9 German patients: 3 classic KS cases, 5 AIDS-associated KS cases, and 1 atypical classic KS case. Additionally, KS autopsy material from the brain of a German AIDS patient was examined. Further biopsies came from 29 Ugandan patients: 16 endemic KS cases and 13 AIDS-associated KS cases. While investigating the ultrastructure, we discovered relatively small-sized bacterial microorganisms within blood capillary spaces of tumor tissue from 5 KS cases of different epidemiological type. The microorganisms often occurred in clusters. They were of coccoid-bacillary form and limited by a wrinkled multilayered cell wall. Many of them were encapsulated. They were not observed outside of the capillary lumen. The bacterial structures were often seen attached to capillary endothelial cells, which sometimes showed blistering into the capillary lumen. The observed bacterial microorganisms obviously represented agents of a bloodstream infection and must have been entrapped and accumulated within capillary spaces of KS tissue. The bacteria, which had an almost identical morphology in all 5 KS cases, could not be identified. If they are of pathogenic significance, it remains unknown.

Kaposi's sarcoma-associated herpesvirus: from cell biology to pathogenesis

Kaposi's sarcoma-associated herpesvirus (KSHV or HHV-8) is linked to the etiopathogenesis of Kaposi's sarcoma, a plasma-blastic variant of Castleman's disease and primary effusion lymphoma. KSHV is related to a number of non-human primate viruses. Only a limited number of KSHV proteins are expressed in tumor cells. Here we discuss the putative role of these proteins in KSHV pathogenesis.

Spindle cell tumors associated with mycobacteria in lymph nodes of HIV-positive patients: 'Kaposi sarcoma with mycobacteria' and 'mycobacterial pseudotumor'

Patients infected with HIV often have unusual manifestations of common infections and neoplasms. One such example is "mycobacterial pseudotumor," an exuberant spindle cell lesion induced in lymph nodes by mycobacteria. Kaposi sarcoma also produces a spindle cell proliferation in lymph nodes of HIV-positive patients. These two entities must be differentiated from one another because of differences in treatment and prognosis. We report here, however, three cases of intranodal Kaposi sarcoma with simultaneous mycobacterial infection, the occurrence of which has not been clearly documented. For comparison, we also studied three cases of mycobacterial pseudotumor, of which 14 cases have been described to date. There was considerable histologic overlap between these two lesions. Acid-fast bacilli were present in all cases, predominantly in the more epithelioid histiocytes in the cases of Kaposi sarcoma, and in spindle and epithelioid cells in the cases of mycobacterial pseudotumor. The morphologic features that favored Kaposi sarcoma over mycobacterial pseudotumor were the prominent fascicular arrangement of spindle cells and slitlike spaces, the lack of granular, acidophilic cytoplasm, and the presence of mitoses. Immunohistochemistry was a reliable adjunct study in the differential diagnosis, as the spindle cells in mycobacterial pseudotumor were positive for S-100 protein and CD68 whereas those of Kaposi sarcoma were CD31- and CD34-positive but negative for S-100 protein and CD68. Awareness that Kaposi sarcoma may coexist with mycobacterial infection in the same biopsy specimen is important because these lesions may be misdiagnosed as mycobacterial pseudotumor. The clinical impact of distinguishing between Kaposi sarcoma with mycobacteria and mycobacterial pseudotumor is significant because the presence of Kaposi sarcoma alters treatment and prognosis.

[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.

Infectious agents and the etiology of chronic idiopathic diseases

At the end of the nineteenth century, the field of microbiology was born, and the infectious nature of many previously unexplained diseases was illuminated as powerful new technology was applied. At the end of the twentieth century, the etiology of myriad chronic diseases remains unexplained. We have argued that many of these diseases have clinical, epidemiological, and pathological features that suggest a role for microbes in their pathogenesis. Although definitive evidence of microbial disease causation is lacking, we believe that new technologies, such as sequence-based microbial identification, will successfully be applied to many of these chronic idiopathic diseases in the near future. As novel pathogens and previously described pathogens are revealed as the causative agents for some of these conditions, new diagnostic, preventive, and therapeutic modalities may emerge, transforming some diseases from idiopathic and chronic, to infectious and curable.

[Detection of human herpesvirus 8 in patients with Kaposi's sarcoma or Castleman's disease associated with AIDS]

A new herpesvirus provisionally termed as KSHV or HHV-8 has been detected in lesions from AIDS-based Kaposi's sarcoma (KS) and from other KS clinical forms, and also in other tumors such as body cavity-based lymphomas or Castleman's disease (CD). We have assessed the presence of this novel herpesvirus in specimens from patients diagnosed with either AIDS and KS or AIDS and CD. DNA samples from skin lesions and peripheral blood obtained from 8 patients diagnosed with AIDS, seven with KS and one with multicentric CD were analyzed; skin specimens and peripheral blood samples from volunteer blood donors or from KS and CD free HIV seronegative patients were used as controls. Detection of the virus was done by PCR amplification of KS330 region, one of the HHV-8 sequences first reported. All skin lesions analysed tested positive for KS330; peripheral blood samples from 5 of the patients, including the one diagnosed with CD, showed also the virus sequence. All skin specimens and peripheral blood samples from controls were negative. From our results it can be concluded that the novel herpesvirus HHV-8 can also be detected in patients with AIDS-associated KS and AIDS-associated CD in Spain.

[Mycoplasmas and AIDS]

AIDS is a complex illness due to HIV type 1 and 2 infection. It is characterized by an important immunodeficiency mainly caused by depletion of CD4+ T lymphocytes. The reasons for this depletion have not been sufficiently clarified yet. In 1986, Shy Ching Lo astonished the scientific community with reported evidence concerning the direct role played by mycoplasma in the etiopathology of AIDS. Since then, different theories have pointed to mycoplasma as cofactors, commensals or opportunistic agents. Although in vivo and in vitro experiments are controversial they suggest a possible mechanism that would explain the synergism between both agents: the mycoplasma belonging to normal intestinal flora could move to urethra, oropharynx or blood due to high risk sexual practice. There it would proliferate favoured by early immunological disorders related to HIV. It has been speculated that several microorganisms including mycoplasma, acting as superantigens, could induce a chronic CD4+ and CD8+ T lymphocytes activation resulting in apoptosis of the infected lymphocytes. The release of cytokines induced by mycoplasma could influence the progression of the disease.

Open reading frame 26 of human herpesvirus 8 encodes a tetradecanoyl phorbol acetate- and butyrate-inducible 32-kilodalton protein expressed in a body cavity-based lymphoma cell line

DNA sequences corresponding to a novel herpesvirus (human herpesvirus 8 [HHV8]) are associated with Kaposi's sarcoma (KS), Castleman's disease, and body cavity-based lymphomas (BCBL). Studies of a BCBL-derived cell line suggest a direct correlation between seropositivity against antigens specifically present in such lines and the development of KS. We have generated recombinant proteins corresponding to open reading frame (ORF) 26 of HHV8 and have produced affinity-purified antibodies. Using these antibodies, we studied the expression of HHV8 ORF26 in a BCBL-derived cell line and found that it encodes a cytoplasmic protein whose expression is induced 16-fold by treatment with phorbol ester or sodium butyrate. This protein induction correlates with a significant induction of viral RNA transcripts. Interestingly, under our experimental conditions minimal increases in viral DNA were observed. No antibodies to the ORF26 protein of HHV8 were found in the sera from two human immunodeficiency virus-positive patients with KS as determined by immunoprecipitation analysis. However, antibodies in the sera from the two KS patients immunoprecipitated a 34-kDa protein found in extracts from induced BCBL1 cells that was not recognized by the control sera.

Presence of human herpesvirus 8 variants in the oral tissues of human immunodeficiency virus-infected persons

A 210-bp DNA segment specific to the human herpesvirus 8 (HHV-8) genome was amplified by nested polymerase chain reaction from 10 of 14 archived oral biopsy samples of HIV-positive patients in London who had no evidence of oral Kaposi's sarcoma (KS). Various oral sites were represented. Oral tissues from 20 general dental patients not known to be HIV-infected were negative. When DNA sequences of these products were compared with sequences derived from 5 oral KS tissues of AIDS patients in London and 10 skin biopsies of Italian patients with Mediterranean KS (total number of positive tissues = 25), 11 were found to be unique. DNA and predicted peptide motifs of these sequences were also different from those in 28 of 36 HHV-8-positive lesions previously reported from American and African patients. HHV-8 is tropic for the oral mucosa of HIV-infected persons, and HHV-8 variants, though diverse, may be geographically restricted.

Pathogenesis of AIDS--related Kaposi's sarcoma. Evidence of a viral etiology

Kaposi's sarcoma is the most common malignancy in patients with HIV infection. New studies point to the involvement of a new human Kaposi's sarcoma herpes virus (KSHV) as a transforming agent. After transformation, cytokine perturbations facilitate growth and in some cases clonal growth occurs. This results in a malignancy with devastating clinical consequences. A clear understanding of the mechanism of transformation by KSHV will lead to better therapies.

The Kaposi sarcoma-associated herpesvirus (KSHV) is present as an intact latent genome in KS tissue but replicates in the peripheral blood mononuclear cells of KS patients

Short DNA sequences have been identified, originally in association with Kaposi's sarcoma (KS) biopsies, that are highly homologous to oncogenic, lymphotropic herpesviruses. Recently a virus, Kaposi sarcoma associated herpesvirus (KSHV) or human herpesvirus-8 (HHV-8), bearing these sequences has been identified in a cell line derived from a body cavity-based lymphoma. In this report, we show that the same sequences are present in KS biopsies as DNA molecules of a form and size characteristic of latent herpesviruses-large, covalently closed, circular episomes. The genomes migrate with an apparent size larger than the herpesvirus Epstein-Barr virus (172 kb). This form of the viral genome was found in four of four biopsies and three of five peripheral blood samples from KS patients. Linear forms of the viral genome, characteristic of viral replication, were not detected in the biopsies, but were present in the peripheral blood of three out of five patients. The sequences for KSHV/HHV-8 were also detected in the blood of four of five allograft patients and three of five healthy donors without KS suggesting that the virus is widespread throughout the human population.

Frequency and distribution of herpesvirus-like DNA sequences (KSHV) in different stages of classic Kaposi's sarcoma and in normal tissues from an Italian population

The frequency and distribution of herpesvirus-like DNA sequences (KSHV) were investigated by PCR in the pathologic skin lesions of a series of 22 HIV-negative elderly patients with classic Kaposi's sarcoma (KS) from Italy, one of the few regions of the world where classic KS is prevalent. Viral sequences were clearly identifiable in 15 cases, in particular in 2 of 5 patch, in 3 of 6 plaque and in 10 of 11 nodular lesions. Our findings confirm the association of these herpesvirus-like DNA sequences with KS in unrelated populations, providing evidence of the putative KS-associated agent in all different histologic lesions of the disease, mainly in the nodular stage. The search for other herpesviruses by PCR showed that Epstein-Barr virus (EBV) sequences were present in 7 of 22 pathologic skin lesions. In 4 cases, both EBV and KSHV were present. On the contrary, all 22 classic KS specimens were negative for human herpesvirus-6 sequences. Two of 3 patch and the 1 nodular lesions from AIDS-related KS patients examined were positive for KSHV but negative for both EBV and HHV-6 sequences. Furthermore, we evaluated the prevalence of KSHV sequences in the normal population of the same geographical area. Thirteen peripheral blood mononuclear cell samples, 9 salivary gland tissues and 6 saliva samples from healthy subjects were invariably found negative for KSHV, using the same PCR technique. Of interest, 2 of 11 hyperplastic tonsils harboured these herpesvirus-like sequences, suggesting that, like other herpesviruses, the KS- associated agent may be harboured in a proportion of normal individuals and tonsils may represent at least one of the possible reservoirs of this putative lymphotropic gamma-herpesvirus in vivo.

Herpesvirus-like DNA sequences detected in endemic, classic, iatrogenic and epidemic Kaposi's sarcoma (KS) biopsies

The identification of Kaposi's sarcoma (KS) clusters in sub-equatorial Africa (endemic KS, AKS) and the high frequency of KS in sexually transmitted AIDS (epidemic KS, EKS), have previously suggested a role for infectious agents in the etiopathogenesis of KS. The recent identification of herpesvirus (HHV)-like DNA sequences in one case of EKS and their detection in > 90% of all tested EKS, prompted us to determine the prevalence of these viral sequences in all types of KS, such as AKS, EKS, classic KS (CKS) and iatrogenic KS (IKS). The presence of herpesvirus(HHV)-like DNA sequences has been examined in 61 KS skin tumors obtained from Greece, Italy, USA, Uganda and Kenya. All KS types (100%) were positive by polymerase chain reaction (PCR) and Southern-blot analysis, while 5 out of 6 (83%) and 4 out of 7 (57%) uninvolved autologous skin biopsies from AKS and CKS patients, respectively, were positive for HHV-like sequences. All samples from non-KS patients were negative, i.e. 17 human biopsies from healthy individuals or patients affected by other pathologies, 5 human cell lines and 15 peripheral blood mononuclear cells (PBMC) from HIV-positive subjects. These results suggest that HHV-like sequences play a major role in the pathogenesis of this neoplasm.

Association of Mycoplasma penetrans with human immunodeficiency virus infection

A cross-sectional study was done to determine the seroprevalence of Mycoplasma penetrans in human immunodeficiency virus (HIV) type 1-seropositive and -seronegative persons recruited in France. The data were analyzed with respect to the sociodemographic, clinical, and biologic status of the patients. M. penetrans seropositivity was associated with HIV infection (18.2% of HIV-seropositive vs. 1.3% of HIV-seronegative persons were M. penetrans-seropositive; P < .001). M. penetrans infection was predominantly but not exclusively associated with homosexual practices in HIV-seropositive subjects and thus presumably sexually transmitted. M. penetrans seroprevalence increased with progression of HIV-associated disease. No association was found between M. penetrans and Kaposi's sarcoma. Thus, there is an unambiguous association between M. penetrans and HIV, particularly among homosexual persons, but its clinical significance remains to be investigated.

Kaposi's sarcoma-associated herpesvirus-like DNA sequences in multicentric Castleman's disease

Multicentric Castleman's disease (MCD) is an atypical lymphoproliferative disorder defined using clinical and pathologic criteria. A characteristic of the MCD is a close association with Kaposi's sarcoma (KS), which occurs during the clinical course of most human immunodeficiency virus (HIV)-associated MCD cases and also, but less frequently, in HIV-negative patients. Recently, sequences of a putative new Herpesvirus (KSHV) have been isolated and further detected in almost all the acquired immunodeficiency syndrome (AIDS) KS and in most of the non-AIDS KS samples. In this study, we searched for these Herpesvirus-like sequences in MCD samples of 31 patients. KSHV sequences were detected in 14 of 14 cases of HIV-associated MCD, including 5 cases without detectable KS. Moreover, KSHV was detected in 7 of 17 MCD cases in HIV-negative patients, including 1 case associated with a cutaneous KS. In 34 non-MCD reactive lymph nodes (follicular and/or interfollicular hyperplasia) in HIV-negative patients, KSHV was detected in only 1 case. In 1 HIV-negative case of MCD, KSHV was found in both the lymph node and peripheral blood samples. These data suggest that KSHV could play a role in the pathogenesis of MCD, especially in HIV-infected patients.

Oral leishmaniasis and Kaposi's sarcoma in an AIDS patient

In the Mediterranean basin area, visceral leishmaniasis is an endemic disease caused by Leishmania donovani infantum. This study describes the clinical and pathological features of one patient with AIDS who had oral (tonsillar) leishmaniasis, caused by a viscerotropic zymodeme, concurrent with a Kaposi's sarcoma and with a CMV infection.

In vitro antibiotic susceptibility testing of different strains of Mycoplasma fermentans isolated from a variety of sources

The in vitro susceptibilities to antibiotics of 24 strains of Mycoplasma fermentans (isolated from human immunodeficiency virus type 1-infected AIDS patients, non-AIDS patients with acute respiratory disease, and tissue culture) were determined. MICs for 90% of the strains tested (micrograms per milliliter) were obtained for chloramphenicol (1.25), ciprofloxacin (0.078), clindamycin (0.078), doxycycline (0.625), erythromycin (> 10), gentamicin (> 10), levofloxacin (0.078), lincomycin (0.156), streptomycin (> 10), and tetracycline (0.625).

AIDS-related malignancies: the emerging epidemic

The incidence of three malignancies has increased in conjunction with the epidemic of human immunodeficiency virus (HIV) disease, and they are currently considered acquired immunodeficiency syndrome (AIDS)-defining conditions. These are Kaposi's sarcoma, associated with AIDS since the onset of the epidemic in 1981; intermediate or high-grade B-cell lymphoma, which became AIDS-defining in 1985; and cervical carcinoma in HIV-infected women, formally recognized as an AIDS-defining diagnosis on January 1, 1993. Approximately 40% of all patients with AIDS have developed cancer during the course of HIV infection. Further, as survival has improved in HIV disease, the incidence of these malignancies has increased. It is thus expected that greater numbers of patients with AIDS-related lymphoma and cervical cancer will be diagnosed in the years ahead. The epidemiologic factors associated with neoplastic disease differ among patients with the three AIDS-related malignancies. The pathogenesis of neoplastic disease also differs. The specific etiologic steps in the development of AIDS-related Kaposi's sarcoma and lymphoma are currently unknown. However, a great deal of information has already been acquired, which may have bearing on the pathogenesis of malignant disease in general, as well as the elucidation of future therapeutic modalities. The specific epidemiologic, etiologic, and clinical characteristics of the AIDS-related malignancies will be described herein. It is hoped that this review will serve to outline our current understanding of this area, to introduce the questions and controversies which are apparent in the field, and to mention those areas in which future research might be focused.

[Bacillary angiomatosis. A pseudoneoplastic infection in AIDS patients]

Bacillary angiomatosis is a newly recognized pseudoneoplastic vascular disease seen in the setting of human immunodeficiency virus (HIV) infection. The disease is characterized by a cutaneous infection with reddish papules or nodules that are similar to pyogenic granulomas or Kaposi's sarcoma in clinical appearance. It is caused by the mildly gram-negative bacillus Rochalimaea henselae, which can be identified in tissue sections by means of Warthin-Starry stain. The historical, clinical, histopathological, and microbiological aspects and the differential diagnosis and therapy of bacillary angiomatosis are reviewed. It is important to be aware of these characteristics, because these lesions can easily be treated with antibiotic therapy.

Otologic neurotologic manifestations of HIV-related disease

Human immunodeficiency virus (HIV), the causative agent of acquired immunodeficiency syndrome (AIDS), has reached worldwide epidemic proportions and is increasing. Otologists, neurotologists, and audiologists practicing in metropolitan centers in North America can expect to encounter patients with HIV-related illnesses, including patients with AIDS-related complex (ARC) and AIDS. Five representative cases are presented: chronic otitis media, facial palsy, Gradenigo's syndrome with facial paralysis, otosyphilis, and Kaposi sarcoma of the mastoid. The common link in all cases was HIV infection. This presentation discusses the management of several HIV-infected patients with otologic and neurotologic findings. HIV infection has extended to all parts of North America. The worldwide incidence is increasing. As the epidemic continues to unfold, new challenges to both the diagnosis and treatment of otologic and neurotologic disease in HIV-positive patients will confront the audiologist and otolaryngologist. Recommendations for the safety of the examining audiologist and treating physician are given.

Oral manifestations of cytomegalovirus infection

Disease caused by cytomegalovirus is reported with increasing frequency. Cytomegalovirus is an important pathogen in immunocompromised and immunosuppressed patients. The most common manifestation of cytomegalovirus infection of the gastrointestinal tract including the oral mucosa is ulceration. The role of cytomegalovirus in xerostomia, Sjögren's syndrome, and Kaposi's sarcoma is continuing to be investigated. This article reviews the oral manifestations of cytomegalovirus, including recently reported oral manifestations.

HIV-1 infection and modulation of cytokine and growth factor expression in Kaposi's sarcoma-derived cells in vitro

OBJECTIVES

HIV-1 transcripts have been detected in AIDS-related Kaposi's sarcoma (KS) tissues within the factor XIIIa + dermal dendrocytes present in the tumor. Various cytokines and growth factors have been shown to influence the growth of KS-derived cells in vitro. HIV-1 preferentially infects CD4+ cells and has also been found to infect some CD4- cells in vitro. The susceptibility of cultured KS cells in vitro to infection with HIV-1 and the expression of interleukin (IL)-1 beta, IL-6 and basic fibroblast growth factor (bFGF) after exposure to HIV-1 was examined.

METHODS

The susceptibility of two different KS-derived cell cultures to HIV-1 infection was examined by the expression of p24 antigen, detection of proviral sequence and electron microscopy. The expression of IL-1 beta, IL-6 and bFGF was detected by enzyme-linked immunosorbent assay and reverse transcriptase polymerase chain reaction.

RESULTS

KS-derived cells can be infected by HIV-1 in vitro. Both KS-derived cells were found to express CD4 mRNA. The expression of IL-1 beta and IL-6 was increased, whereas the expression of bFGF was not stimulated after exposure of KS cells to HIV-1.

CONCLUSION

These experiments describe the in vitro infection of KS-derived cells by HIV-1 and the expression of various cytokines and growth factor following infection. The increased production of cytokines observed following such infection may be involved in the pathogenesis of AIDS-related KS.

Multiple pathogens may induce growth factor cascade resulting in KS

While lipopolysaccharide endotoxin is the most prominent inducer of the kinecascade (TNF alpha, IL-1, 4, 6, 8) that leads to shock and multiple organ failure, bacterial exotoxins and products of certain gram positive bacteria can induce the same end results. We theorize that more than one pathogen can induce the sequence of protooncogene activation and growth factor release that results in the formation of KS. If KS has its own unique viral etiology, this virus has not as yet been isolated or identified but we continue to search for it. However, it is entirely possible that these lesions do not have a single well-defined etiologic agent but are the result of multiple agents cooperating in a set sequence. An endogenous, or apathogenic exogenous, retrovirus may replace HIV for initiator growth factor induction in CD4 cells in the classical (Mediterranean) or iatrogenic disease; and other pathogens co-exist or sequentially replace each other in the African endemic disease; whereas an array of viral pathogens (prominent among them CMV) take over growth factor induction in endothelial cells proliferating in response to the initiator growth factor (oncostatin M) released from HIV-infected CD4 lymphocytes in AIDS-KS.

The absence of Tat sequences in tissues of HIV-negative patients with epidemic Kaposi's sarcoma

OBJECTIVE

Tat, an essential regulatory protein of HIV, acts as a growth factor for Kaposi's sarcoma (KS)-derived cells in culture. We tested the hypothesis that HIV-negative epidemic KS patients who are also at high risk for HIV disease might have been infected with a defective HIV-1 virus that retained the ability to express Tat.

METHODS

We evaluated the presence of Tat sequences in KS tissue and peripheral blood mononuclear cells (PBMC) of HIV-1-negative individuals with epidemic KS who had risk factors for HIV infection by polymerase chain reaction using specific primers for the Tat region of HIV-1.

RESULTS

No evidence for the presence of Tat-1 sequences or for Tat-expressing defective HIV-1 virus was found.

CONCLUSION

These results suggest that HIV-1 Tat does not play a role in the initiation of KS in HIV-1-negative individuals. Tat might play an indirect role in epidemic KS in HIV-infected patients.

Clinical aspects of Kaposi's sarcoma

Kaposi's sarcoma is the most common tumor found in patients with the acquired immunodeficiency syndrome. This opportunistic neoplasm has characteristics of a sexually transmitted disease. Growth factors, cytokines, immune suppression, and interaction with infectious organisms all appear to play a role in the pathogenesis of this enigmatic disorder. The manifestations of Kaposi's sarcoma are protean, and lesions may appear at any time in the course of human immunodeficiency virus disease, remain localized and asymptomatic, or spread aggressively and cause morbidity. Treatment, which must be individualized, ranges from observation, local therapy with cosmetic makeup, and cryotherapy with liquid nitrogen or local intralesional injection of agents, to radiotherapy and systemic therapy with interferon-alpha and cytotoxic chemotherapy.

Pathogenesis of human immunodeficiency virus-related Kaposi's sarcoma

Infection with the human immunodeficiency virus-1 is associated with a marked increase in the incidence of Kaposi's sarcoma. Recent studies suggest that the risk of Kaposi's sarcoma in human immunodeficiency virus infection is increased with oral-fecal contact and that a sexually transmitted agent possibly related to human papillomavirus-16 could be involved. Exposure to this or another sexually transmitted agent apparently alters both the morphology and growth regulation of the Kaposi's sarcoma progenitor cells. These changes include the expression of the alpha chain of the interleukin-6 receptor with the acquisition of an interleukin-6-dependent autocrine growth loop. Subsequent perturbation of multiple cytokines during human immunodeficiency virus infection, including Oncostatin-M, interleukin-1 beta and tumor necrosis factor-alpha alters the subsequent growth of Kaposi's sarcoma. These studies suggest that control of cytokine perturbations or the underlying human immunodeficiency virus-1 infection should result in a significant reduction in the rate of growth of acquired immunodeficiency syndrome-related Kaposi's sarcoma.

Kaposi sarcoma in Okinawa

BACKGROUND

The authors encountered six patients with Kaposi sarcoma in Okinawa; one was classic type, two were associated with adult T-cell leukemia (ATL), one was with multiple myeloma, and two were with acquired immune deficiency syndrome (AIDS). In the classic type, many nodular lesions were seen on the skin of the extremities and a few on the trunk, some of which were ulcerated. Most lesions regressed in 1.5 years. In four other patients (three without AIDS and one with AIDS), many plaques and a few nodular lesions were seen on the trunk, face, and extremities. The other patient with AIDS showed Kaposi sarcoma only in the lymph nodes and perineural tissues in the abdomen.

METHODS

Immunohistochemical and lectin histochemical studies were done on deparaffinized sections and on cells cultured from small pieces of tumor mass from the classic type Kaposi sarcoma. Isolation of viruses from tumor tissue was also attempted.

RESULTS

Large numbers of endothelial cells lining irregular vascular spaces, and some spindle cells showed positive reactions for Factor VIII-related antigen, Ulex europaeus 1 (UEA-1) (E.Y. Labs, Inc., San Mateo, CA), Griffonia simplicifolia (GS-1) (E.Y. Labs, Inc.) lectins, and epidermal growth factor (EGF) receptor antigen. Cytomegalovirus (CMV), hepatitis B, herpes simplex virus (HSV) 1 and 2, papillomavirus antigens, and human immunodeficiency virus (HIV) p24 core antigen were not seen in any patients, except in the patient with AIDS in whom CMV was demonstrated in tissues adjacent to the tumor (Patient 6). In cell culture, elongated spindle cells proliferated in plate and also in three-dimensional cultures. The cells were positive immunohistochemically for Factor VIII-related antigen and EGF receptor. They also stained lectin histochemically with UEA-1 and GS-1. Tube formations were demonstrated by electron microscopic study.

CONCLUSIONS

Six cases of Kaposi sarcoma have been diagnosed within a short time span where this condition has previously been said to be rare. The studies suggest a vascular endothelial cell origin and growth factor regulated growth for this tumor.

Human T-cell leukemia virus type I or a related retrovirus in patients with mycosis fungoides/Sézary syndrome and Kaposi's sarcoma

Antibodies reactive with human T-cell leukemia virus type I (HTLV-I) proteins p19, p24, gp46, p56, and gp68 were detected in four of 27 patients with mycosis fungoides/Sézary syndrome (MF/SS) and one patient with Kaposi's sarcoma using radioimmunoprecipitation and Western blot analysis. Seroreactivity patterns to HTLV-I proteins of MF/SS sera were indeterminate or limited in comparison with sera of patients with adult T-cell leukemia/lymphoma. HTLV-I gag- and tax/rex-specific DNA was demonstrated in peripheral blood from three of the MF/SS patients and from the patient with Kaposi's sarcoma by the polymerase chain reaction. HTLV-I-specific DNA sequences were not detected in a cohort of seven seronegative MF/SS patients. The frequency of HTLV-I infection was four of 27 or 14.8% among the MF/SS patients, which is several hundredfold higher than in normal blood donors. The present data suggest a possible association of HTLV-I or a related retrovirus with mycosis fungoides/Sézary syndrome and Kaposi's sarcoma.

High level of HTLV-I specific protein expression in a patient with adult T-cell leukemia, chronic progressive myelopathy and Kaposi's sarcoma

Analysis was made of serum anti-HTLV-I antibodies, virus-specific proteins in peripheral blood lymphocytes (PBL) and proviruses in lymphocyte DNA of a patient with adult T-cell leukemia (ATL), Kaposi's sarcoma, and chronic myelopathy. Using Western blot and PCR (with HIV-1 specific primers), it was shown that Kaposi's sarcoma was not linked to HIV infection. Western blot analysis of serum revealed antibodies against p19, p24 and Pr 53 of HTLV-I. Examination of proteins in fresh PBL by Western blot revealed a high level of HTLV-I specific protein expression. Southern blot analysis of the patient's DNA revealed two different sites for HTLV-I provirus integration.