Search

Dengue virus (DENV) infections may result in asymptomatic cases or evolve into a severe disease, which involves multiple organ failure. Renal involvement in dengue can be potentially related to an increased mortality. Aiming to better understand the role of DENV in renal injury observed in human fatal cases, post-mortem investigations were performed in four DENV-4 renal autopsies during dengue epidemics in Brazil. Tissues were submitted to histopathology, immunohistochemistry, viral quantification, and characterization of cytokines and inflammatory mediators. Probably due the high viral load, several lesions were observed in the renal tissue, such as diffuse mononuclear infiltration around the glomerulus in the cortical region and in the medullary vessels, hyalinosis arteriolar, lymphocytic infiltrate, increased capsular fibrosis, proximal convoluted tubule (PCT) damage, edema, PCT debris formation, and thickening of the basal vessel membrane. These changes were associated with DENV-4 infection, as confirmed by the presence of DENV-specific NS3 protein, indicative of viral replication. The exacerbated presence of mononuclear cells at several renal tissue sites culminated in the secretion of proinflammatory cytokines and chemokines. Moreover, it can be suggested that the renal tissue injury observed here may have been due to the combination of both high viral load and exacerbated host immune response.

Introduction: Dengue virus (DENV), the etiologic agent of dengue fever illness, represents a global public health concern, mainly in tropical and subtropical areas across the globe. It is well known that this acute viral disease can progress to severe hemorrhagic stages in some individuals, however, the immunopathogenic basis of the development of more severe forms by these patients is yet to be fully understood. Objective: In this context, we investigated and characterized the histopathological features as well as the cytokine profile and cell subpopulations present in liver tissues from three fatal cases of DENV in children. Methods: Hematoxylin and Eosin, Periodic Acid Schiff and Picro Sirius Red staining were utilized for the histopathological analysis. Immunohistochemistry assay was performed to characterize the inflammatory response and cell expression patterns. Results: Vascular dysfunctions such as hemorrhage, vascular congestion and edema associated with a mononuclear infiltrate were observedin all three cases. Liver tissues exhibited increased presence of CD68+ and TCD8+ cells as well as high expression of MMP-9, TNF-a, RANTES, VEGFR-2 mediators. Viral replication was confirmed by the detection of NS3 protein. Conclusion: Taken together, these results evidenced key factors that may be involved in the development of severe alterations in liver tissues of children in response to DENV infection. [ABSTRACT FROM AUTHOR]

The term schistosomiasis encompasses a group of infectious disorders caused by five species of the genus Schistosoma, a blood trematode of outstanding importance in tropical areas. Some of these disorders have long been associated with malignant neoplasia, the most striking association being between disease caused by Schistosoma haematobium, the predominant etiological agent of urinary schistosomiasis, and squamous cell carcinoma of the bladder, a relatively uncommon vesical cancer in non-endemic areas. Four cases of simultaneous adenocarcinoma and schistosomiasis of the prostate have been previously reported (S. haematobium in three and S. mansoni in one). We report a fifth case of concomitant adenocarcinoma and schistosomiasis of the prostate in a 68-year-old Brazilian patient infected with S. mansoni. We also review the medical literature on the association between schistosomiasis and cancer.

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.

Mycobacterium haemophilum is a nontuberculous mycobacterium that causes localized or disseminated disease, mainly in immunocompromised hosts. We report the case of a 35-year-old HIV-infected woman who presented with several enlarging cutaneous lesions over the arms and legs. Histopathological examination revealed the diagnosis of a cutaneous mycobacterial disease. Mycobacterial analyses unveiled M. haemophilum infection. Six months after completion of a successful antimycobacterial treatment, she developed an immune reconstitution inflammatory syndrome (IRIS). This paradoxical relapse presented as tenderness, redness and swelling at the precise sites of the healed lesions and took place in the setting of significant recovery of the CD4 cell count (from 05 to 318 cells/mm3). Microbiological analyses of these worsening lesions were negative, and they spontaneously remitted without the initiation of a novel antimycobacterial treatment cycle. M. haemophilum infection should always be considered as a cause of skin lesions in immunocompromised subjects. Physicians should be aware of the possibility of IRIS as a complication of successful antiretroviral therapy in HIV-infected patients with M. haemophilum infection. [ABSTRACT FROM AUTHOR]

Lymphoproliferative disorders associated with hepatitis C virus (HCV) make up a heterogeneous group of diseases, including lymphomas. It was only recently that HCV was recognised as being a potential cause for the development of non-Hodgkin's lymphoma. The authors report a case of an older woman with chronic hepatitis C who developed primary spleen lymphoma. This case report points out the pathophysiological mechanisms of this disease and the importance of considering this disease in the differential diagnosis of patients with chronic HCV infection. [ABSTRACT FROM AUTHOR]

Background: A rubella mass vaccination campaign targeting 15-29-year-old women was performed in Brazil in 2001-2002. Rubella vaccination was contraindicated during pregnancy. A follow-up protocol was implemented for pregnant women who were vaccinated as well as their newborns. The risks of congenital rubella syndrome (CRS) and congenital rubella infection (CRI) after vaccination were assessed according to the pregnant women's immune status., Methods: This was a prospective, noncontrolled study of pregnancy outcomes in women vaccinated against rubella in the state of Rio de Janeiro, including clinical and laboratory evaluations., Results: Of 2292 reported pregnant women who were vaccinated, 1636 had known outcomes: there were 1577 newborns (96.4%), 52 miscarriages (3.2%), and 7 stillbirths (0.4%). Gestational age at vaccination was ≤ 5 weeks in 75% of the susceptible, vaccinated pregnant women. Nine newborns were positive for immunoglobulin M; 4 were born to susceptible pregnant women, for a 2.0% CRI rate (95% confidence interval, .5%-4.9%); 4 were born to vaccinated pregnant women with indeterminate or unknown status; and 1 had CRS, with a wild-type virus infection., Conclusions: The absence of vaccine-related CRS cases further supports recommendations to not interrupt a pregnancy exposed to rubella vaccine virus. Monitoring pregnancy outcomes and CRI with vaccine virus can distinguish between wild-type and vaccine virus infections, especially in situations of viral circulation.

Background: Glomus tumor is a benign neoplasm of uncommon occurrence in daily practice, more frequently observed as a single painful lesion, at the distal phalanges of the fingers. Multiple presentation is very rare, with fewer than 200 reports, usually presenting as small angiomatous lesions with discrete pain., Objectives: The study's objective was to analyze the epidemiologic, clinical, therapeutic, and histopathologic aspects in a series of six cases of multiple glomus tumors., Results: All patients were men, between 12-45 years of age. The tumor was congenital or appeared between 3-25 years of age. The clinical picture oscillated between three to 10 lesions, as macules, nodules, or tumors, with colors varying from bluish, brown-bluish, violet, to normochromic. The lesions were detected in the trunk and one or more members, not affecting the head, hands, and feet. Pain was discrete or absent. Incisional biopsy for histopathologic evaluation with the hematoxylin-eosin staining confirmed the diagnosis of glomus tumor in all cases. It showed the characteristic glomus cells and vascular spaces. The complete excision of the tumorous plaque was performed in one patient and a complex corrective procedure is still to be performed for one aberrant tumor in another case. The other patients received advice about their disease and were asked to periodically return., Conclusion: Because this is a very uncommon illness, the present series allowed the demonstration of the wide variety of epidemiologic and clinical aspects described in the literature, with the presentation of elements that may improve its recognition and diagnosis.

The term schistosomiasis encompasses a group of infectious disorders caused by five species of the genus Schistosoma, a blood trematode of outstanding importance in tropical areas. Some of these disorders have long been associated with malignant neoplasia, the most striking association being between disease caused by Schistosoma haematobium, the predominant etiological agent of urinary schistosomiasis, and squamous cell carcinoma of the bladder, a relatively uncommon vesical cancer in non-endemic areas. Four cases of simultaneous adenocarcinoma and schistosomiasis of the prostate have been previously reported (S. haematobium in three and S. mansoni in one). We report a fifth case of concomitant adenocarcinoma and schistosomiasis of the prostate in a 68-year-old Brazilian patient infected with S. mansoni. We also review the medical literature on the association between schistosomiasis and cancer.