[Chlamydophila pneumoniae: from its proteomics to arteriosclerosis]

Chlamydophila pneumoniae is a highly prevalent intracellular human pathogen with a unique biphasic life cycle. It is a common cause of upper respiratory infection and pneumonia, and is currently being studied as a potential risk factor for the development of atherosclerotic cardiovascular disease. The outer membrane surface antigens of C. pneumoniae are highly complex: some, such as the major outer membrane protein, are specific, but poorly immunodominant, whereas others have stronger immunogenicity, but are cross-reactive among Chlamydia species. Therefore, new, highly immunodominant, species-specific antigens should be sought. In this regard, the polymorphic membrane proteins (PMPs) are a) unique to Chlamydiae, b) often exposed on the surface of the bacteria, and c) highly immunogenic; these factors make them potential candidates for application in laboratory assays. Other chlamydial antigens, such as heat shock protein (HSP) 60, have been associated with atherosclerotic lesions because of their ability to induce an immunological attack on the endothelial wall. Over the last decade, several studies have suggested a potential role of chronic C. pneumoniae infection in human atherosclerosis. Nevertheless, prospective studies with sufficiently large samples and a healthy comparison group, using a combination of direct and indirect microbiological techniques in the same subject and sample, are needed to establish a relationship between the infection and disease activity.

Inflammatory choroidal neovascular membrane in presumed ocular Lyme borreliosis

INTRODUCTION

Lyme disease is a multisystemic disease with protean ocular manifestations. We describe the occurrence of inflammatory choroidal neovascular membrane (CNVM) in two patients suffering from presumed Lyme disease.

METHODS

Descriptive review of the clinical records of two patients.

RESULTS

Patient 1: 16-year-old healthy male presenting with a visual acuity of counting fingers [oculus dexter (OD)] and 6/6 [oculus sinister (OS)] 3 months after a tick bite. He had papillitis and an exudative subretinal macular lesion OD. Treatment was started with intravenous (IV) ceftriaxone; a week later, IV methylprednisolone was administered with a tapering dose of oral steroids thereafter. Three months later, VA had improved to 3/60 OD. Patient 2: 38-year-old healthy female presenting with reduced left-eye vision (6/24) 6 weeks after a tick bite. She also suffered from erythema migrans and arthralgias. She had left-eye papillitis, macular haemorrhages and vascular sheathing. Treatment was started with IV ceftriaxone. One month later, there was profound loss of vision with development of CNVM. Treatment was declined by the patient and eventually retinal fibrosis developed.

CONCLUSION

Inflammatory CNVM has not been described previously in the setting of ocular Lyme borreliosis. We herein describe the occurrence of inflammatory CNVM in two patients whose diagnosis with Lyme disease was clinically based--both were sero-negative. Visual outcome in the two patients was profoundly impaired because of the ensuing macular scar.

Infection and vasculitis

Vasculitis may be associated with infection, immunization or anti-microbial drugs. Infections are responsible for a number of different types of vasculitis. Conversely, patients with vasculitis may develop infections, which sometimes mimic relapse. The aim of this review is to summarize the various aspects of the inter-relationship between vasculitis and infection, and the physiopathological mechanisms involved, in light of our current knowledge from animal models. Currently, a causal relationship between infection and vasculitis has only been established in a few instances and many mechanisms remain hypothetical. This inter-relationship is further assessed from the point of view of clinical presentation and therapeutic options, based on case reports and prospective observational data.

Infections, connective tissue diseases and vasculitis

In genetically predisposed individuals, viruses, bacteria, or parasitic infectious agents are suspected of inducing autoimmunity and/or exacerbating autoimmune rheumatic diseases (ARD) once self-tolerance is broken. Although direct evidence for this association is still lacking, numerous data from animal models as well as from humans support the hypothesis of a direct contribution of pathogens to the induction of several ARD. This review focuses on the possible role of infectious agents as triggers of autoimmunity in systemic lupus erythematosus, polymyositis-dermatomyositis, antiphospholipid antibody syndrome, and primary vasculitis. Indeed, vasculitis may be a clinical manifestation of an infectious disease (secondary vasculitis). In addition, immune response abnormalities and immunosuppressive medications may be responsible for the high percentage of infectious complications in ARD patients. Recent therapeutic approaches aimed at lowering doses of cytotoxic agents and shortening duration of treatment with the most toxic drugs, have proved to be as effective as conventional regimens. New drugs and strategies aimed at preventing infections could further improve the outcome of ARD patients.

Extracutaneous sporotrichosis in a patient with liver cirrhosis

We report an unusual case of disseminated cutaneous sporotrichosis with oral mucous and tracheal involvement in a forty-year-old male with a history of heavy drinking and liver cirrhosis. We also review the literature and other similar published cases.

Endothelial cells as active participants in veterinary infections and inflammatory disorders

Endothelial cells were once viewed as relatively inert cells lining the vasculature. They are now recognized as active and responsive regulators of coagulation, platelet adhesion, fluid homeostasis, wound healing, leukocyte extravasation and vascular tone. Endothelial cells play a key role in the host response to infectious agents by regulating leukocyte trafficking, producing inflammatory cytokines and presenting antigen in association with major histocompatibility class II (MHC II) molecules. A number of infectious agents have a tropism for endothelial cells. Infection of endothelial cells can promote thrombosis, vascular leakage, and increased adherence and emigration of leukocytes. Furthermore, activation of a systemic inflammatory response, in the absence of direct endothelial cell infection, can also lead to endothelial cell dysfunction. The purpose of this review is to highlight the interactions between endothelial cells and infectious or inflammatory agents that contribute to coagulation disturbances, vasculitis and edema. A select group of viral and bacterial pathogens will be used as examples to demonstrate how endothelial cell dysfunction contributes to the pathogenesis of infectious and inflammatory disorders.

Cutaneous vasculitis associated with Mycoplasma pneumoniae infection: case report and literature review

Mycoplasma pneumoniae is an important bacterial agent that causes pneumonia in pediatric patients; it can also affect other organs or systems. Extrapulmonary manifestations include neurological, cardiac, hematologic, renal, gastrointestinal, osteoarticular, cutaneous, and ocular involvement. This report presents a 7-year-old male affected with cutaneous and retinal vasculitis due to M pneumoniae infection without pulmonary detection. The available literature on cutaneous vasculitis and M pneumoniae infection is also reviewed.

Disseminated gonococcal infection presenting as vasculitis: a case report

A 50-year-old man with alcoholic liver disease presented with fever, tenosynovitis, polyarthritis and a vasculitic rash on the hands and feet for 4 days. He had neutrophilia and raised inflammatory markers. He had no history of sore throat, urethral discharge or travel abroad. His initial blood cultures were negative, and he was treated for vasculitis with steroids. The rash and arthritis seemed to improve initially, but he had another episode of fever. Repeat blood cultures grew Neisseria gonorrhoeae,and he received intravenous ceftriaxone followed by oral ciprofloxacin. He had marked improvement in rash, tenosynovitis and arthritis, and the fever dropped. He also had chlamydial urethritis and received azithromycin. The presentation of disseminated gonococcal infection after a presumptive episode of asymptomatic urethral gonorrhoea is highlighted.

Experimental Coxiella burnetii infection in pregnant goats: a histopathological and immunohistochemical study

Pregnant goats were inoculated subcutaneosly with Coxiella burnetii and the course of infection was studied. Abortion in the last third of pregnancy occurred in all infected animals. Tissues from the placenta and other organs were studied before and after abortion by immunohistochemistry and PCR analysis. After infection, mild lesions were observed in several maternal organs, mainly the mammary gland but also the lung and the liver. The trophoblast cells of the choriallantoic membrane were the first target cells of the placenta; there was, however, a substantial delay between initial infection and placental colonization. In the last weeks of pregnancy, just before abortion, massive bacterial multiplication was detected in the placenta. In this stage of infection a necrotic and suppurative placentitis separated the fetal trophoblast cells from maternal syncytial epithelium. Vasculitis was observed in the fetal mesenchyme. A strong maternal T-cell response was detected in the inter-placentomal areas but not in the placentomes, where only neutrophils and smaller numbers of macrophages were associated with the lesions. Neither lesions nor C. burnetii DNA were found in maternal organs in animals maintained until day 120 post-abortion.

Favorable outcome of IgA nephropathy on antituberculous treatment

We report the case of an association of IgA nephropathy and tuberculosis with superimposed vasculitis lesions on the renal biopsy. Three previous cases of the same association are discussed. The nephropathy had a favorable course in all of these cases on antituberculous treatment only. Tuberculosis is another infection related to IgA nephropathy.

Small vessel vasculitis in a patient with botryomycosis

We describe a 53 year-old woman with primary biliary cirrhosis presenting with left ankle swelling and a purpuric rash. The skin biopsy of the rash revealed a small vessel vasculitis and a botryomycosis with Splendore-Hoeppli phenomenon. Botryomycosis is an uncommon histologic finding of a chronic suppurative bacterial infection whereby bacteria form aggregates, which are surrounded by an eosinophilic matrix. With guidance from the skin biopsy findings, the patient was appropriately treated with antibiotics, resulting in complete resolution of symptoms.

Multi-organ affecting CMV-associated cryoglobulinemic vasculitis

We report on a 67-year-old female patient who was admitted to our intensive care unit with acute renal failure and severe hypoxemia. Transiently, the patient had to be treated with kidney replacement therapies and artificial ventilation. The actual illness started with general weakness, recurrent bloody diarrhea and intermittent dermatitis of the lower legs. Skin symptoms were initially observed 2 years before the actual clinical findings. The bloody diarrhea was attributed to an inflammatory stenosis of the sigma. The life-threatening clinical aggravation was due to diffuse alveolar hemorrhage and alveolitis. In the search for the cause of the systemic disease, both a monoclonal y-globulinemia, causing a cryoglobulinemia type II and an acute cytomegalovirus infection were diagnosed. Additionally, the course of the disease was complicated by a secondary antibody deficiency as well as an endocarditis of the aortic valve caused by Enterococcus faecium. A cryoglobulinemic vasculitis type II was histologically found in biopsy specimen of the kidney. Thus, the present case reports on a coincidence of a monoclonal gammopathy causing a cryoglobulinemia type II with extensive organ involvement and a florid CMV infection. We hypothesize that the CMV infection has triggered the cryoglobulinemia and its particular severe organ involvement.

Subcutaneous infection with Pseudallescheria boydii in an immunocompromised patient

With the broad employment of immunosuppressive therapy, the incidence of Pseudallescheria boydii infections is rising. We report a first case of the localized subcutaneous P. boydii infection in a patient with microscopic polyangiitis. Favorable outcome related to the treatment with voriconazole adds to the growing body of evidence supporting the use of this particular agent in P. boydii infections.

Necrotising cryptococcal vasculitis in an HIV-negative woman

An 84-year-old woman with a past medical history significant for haemolytic anaemia necessitating chronic steroid therapy presented with skin induration and erythema initially thought to be cellulitis. After a rapid progression of symptoms and failure to respond to antibiotics, a clinical diagnosis of necrotising vasculitis was made. Necrotising cryptococcal vasculitis was confirmed by histopathology and culture.

Vasculitides secondary to infections

Many viruses can be responsible for systemic vasculitis, the most frequent being hepatitis B virus-related polyarteritis nodosa (HBV-PAN), even though its incidence has decreased over the past few decades. Mixed cryoglobulinemia has been shown to be associated with hepatitis C virus (HCV) infection in more than 80% of the patients, but it remains asymptomatic in most of them with only a minority developing vasculitis. Human immunodeficiency virus (HIV), erythrovirus B19, cytomegalovirus, varicella-zoster virus and human T-cell lymphotropic virus (HTLV)-1 have also been reported to be associated with or implicated in the development of vasculitides. On the other hand, some bacteria, fungi or parasites can also cause vasculitis, mainly by direct invasion of blood vessels or septic embolization, leading, e.g., to the well-known feature of 'mycotic aneurysm'. Syphilitic aortitis and/or cerebrovascular disease and rickettsial diseases are other, more specific, bacteria-induced vasculitides. Recognizing an infectious origin of vasculitides is of great importance because treatment strategies differ from those applied to non-infectious forms. Effective antimicrobial drugs are mandatory to treat bacterial, parasitic or fungal infections, while the combination of antiviral agents and plasma exchanges has been proven to be effective against HBV-PAN. This latter strategy might also be effective against HIV-associated vasculitis and, unlike cytotoxic agents, does not jeopardize the outcome of HIV-infected patients. In the context of HCV-related cryoglobulinemic vasculitis, antiviral drugs are necessary to achieve recovery, in combination with low-dose corticosteroids and/or rituximab. In the near future, newer antiviral agents will probably also have their place in the therapeutic armamentarium for these patients.

[Chronic bacterial-and-viral vasculitis as a possible risk factor of disordered stability of the coronary atherosclerosis course]

In order to assess the real significance of some plasma and vascular indices in disorders of the stable course of coronary heart disease (CHD) in chronic bacterial- and viral infection-invasion, we determined the blood plasma lipid hydrogen peroxide (LHP) activity, a direct index of the lipid peroxidation degree, and measured the concentration of specific antibodies to Chlamydia pneumoniae (C. pneunoniae), herpes simplex virus type 1 (HSV-1), cytomegalovirus (CMV) and Epstein-Barr virus (EBV) by means of the enzyme-linked immunosorbent assay (ELISA). We examined a total of 70 patients presenting with CHD combined with a concomitant infection both with a stable course of the disease (Group One) and acute coronary syndrome (Group Two), as well as 50 infected people without verified signs of coronary atherosclerosis (Group Three). The comparison group consisted of patients with CHD, being seronegative for the causative agents referred to above. The condition of the major vessels was appropriately assessed by means of duplex ultrasonography (DU). Resulting from the findings of the carried out investigation, we singled out a triad of symptoms characteristic of the transformation of the chronic infectious process into the recurrent phase, which for the CHD patients with the presence of the conventional risk factors of atherosclerosis might become a cause of the disordered stable course of the disease and development of acute ischaemic attacks. The revealed alterations seemed to have been based upon an infectious-origin inflammatory lesion of the vessels, which was duly confirmed by duplex ultrasonography.

Infection-related vasculitis

Infection-related vasculitis constitutes the most common cause of secondary vasculitis. A great variety of microorganisms can induce directly or indirectly inflammatory vascular damage resulting in vascular occlusion, tissue ischemia, and necrosis. In the developed world hepatitis B and C-related vasculitis remain the most common clinical syndromes, while HIV-associated vasculitis remains a concern in developing countries.

Chlamydia pneumoniae burden in carotid arteries is associated with upregulation of plaque interleukin-6 and elevated C-reactive protein in serum

OBJECTIVE

Chlamydia pneumoniae (Cpn) infection of vascular smooth muscle cells increases interleukin-6 (IL-6) secretion in vitro. In vivo, IL-6 stimulates liver C-reactive protein (CRP) production. Because serum levels of IL-6 and CRP are independent risk factors for stroke and myocardial infarction (MI), we investigated whether Cpn burden in carotid plaques might provide a link between plaque IL-6 expression and elevated serum levels of IL-6 and CRP.

METHODS AND RESULTS

Consecutive patients undergoing elective carotid endarterectomy were studied. Serum levels of CRP and IL-6 were measured before surgery. Immunohistochemistry and real-time quantitative (k)RT-PCR were used to detect Cpn and the expression of IL-6 within carotid plaques. Cpn mRNA was present in 19 (37%) of 51 patients, suggesting viable infections. These patients had evidence for infection by PCR and immunohistochemistry. The Cpn burden, measured by real-time quantitative (k)-PCR using the number of organisms normalized against the number of eukaryotic cells in the tissue, was associated with plaque expression of IL-6 (Spearman R=0.55; P<0.0001), which was associated with serum levels of IL-6 (R=0.56; P<0.0001) and CRP (R=0.80; P<0.0001).

CONCLUSIONS

IL-6 secretion in atherosclerotic plaques infected with Cpn could explain elevated serum inflammatory markers in individuals at risk for stroke and MI.

Toll-like receptor 2 mediates persistent chemokine release by Chlamydia pneumoniae-infected vascular smooth muscle cells

OBJECTIVE

The intracellular bacterium Chlamydia pneumoniae is present in many atherosclerotic lesions, where it could promote inflammation. This study determined whether monocyte chemoattractant protein 1 (MCP-1) release is stimulated in vascular smooth muscle cells (VSMCs) that are exposed to or infected by C pneumoniae and whether toll-like receptor 2 (TLR2) or TLR4 mediate these effects.

METHODS AND RESULTS

TLR2 mRNA was expressed constitutively and was upregulated by C pneumoniae exposure in mouse aortic SMC and was inducible by C pneumoniae and TLR3 and TLR4 agonists in human coronary artery SMCs. Exposure to inactivated or viable extracellular C pneumoniae evoked a robust increase in MCP-1 release and activated nuclear factor-kappaB and extracellular signal-regulated kinase 1/2 in wild-type and TLR4 signaling-deficient mouse aortic SMCs but not in TLR2-deficient SMCs, probably because of TLR2-mediated recognition of a chlamydial antigen. Brief exposure to viable C pneumoniae led to active infection of VSMCs, shown by chlamydial protein synthesis, and caused a persistent (>48-hour) MCP-1 release that was also TLR2 dependent.

CONCLUSIONS

The results show that VSMCs express functional TLR2 and that TLR2 mediates both a persistent activation of chemokine release in C pneumoniae-infected VSMCs and its acute stimulation by extracellular C pneumoniae. Therefore, TLR2 expressed in VSMCs may promote inflammation within the arterial wall.

Chronic bacterial-viral vasculitis as manifestation of systemic inflammatory response syndrome in females

Study involved 52 women (mean age 43+/-1,3) without any evidence of CHD, suffering from dull or acute prolonged non-anginal chest pain, with undergoing chronic bacterial-viral infection--Chlamydia pneumonia in combination with HSV-I, CMV and/or EBV. 30--patients serum-positive to plasma markers (IgG antibodies) of previous infection were enclosed in group I, 22--with plasma consumption of IgA+IgG antibody complex demonstrating re-infection/reactivation phase of disease--in group II and 20 healthy serum-negative females (median age 47+/-2,8 years)--controls (group III). The intergroup analysis revealed the complex of disturbances in some plasma parameters of II group patients, namely significant elevation of CRP, F and LPO activity vs. I and III group data, along with reduced parameters of immune status in both groups of infected persons. The patients with mixed infections showed the high frequency of specific re-polarization phase abnormalities, cardiac rhythm and conduction disturbances. These changes together with intimate-medial wall injuries of inflammatory origin disclosed by DS technique enables us to suggest that in women with previous chronic untreated or insufficiently treated infection, in cases of their overload activity, recurrent or super-infection may provide deep immunosuppressive conditions leading to farther cardio-vascular abnormalities.