Immunoactivation and immunopathogeny during active visceral leishmaniasis

Visceral leishmaniasis is caused by protozoan parasites of the Leishmania donovani complex. During active disease in humans, high levels of IFN-γ and TNF-α detected in blood serum, and high expression of IFN-γ mRNA in samples of the lymphoid organs suggest that the immune system is highly activated. However, studies using peripheral blood mononuclear cells have found immunosuppression specific to Leishmania antigens; this poor immune response probably results from Leishmania antigen-engaged lymphocytes being trapped in the lymphoid organs. To allow the parasites to multiply, deactivating cytokines IL-10 and TGF-β may be acting on macrophages as well as anti-Leishmania antibodies that opsonize amastigotes and induce IL-10 production in macrophages. These high activation and deactivation processes are likely to occur mainly in the spleen and liver and can be confirmed through the examination of organ samples. However, an analysis of sequential data from studies of visceral leishmaniasis in hamsters suggests that factors outside of the immune system are responsible for the early inactivation of inducible nitric oxide synthase, which occurs before the expression of deactivating cytokines. In active visceral leishmaniasis, the immune system actively participates in non-lymphoid organ lesioning. While current views only consider immunocomplex deposition, macrophages, T cells, cytokines, and immunoglobulins by diverse mechanism also play important roles in the pathogenesis.

Modulatory activity of antioxidants against the toxicity of Rifampicin in vivo

The World Health Organization (WHO) has shown concern about the burden of tuberculosis in the developing countries. Even though rifampicin is an effective drug in the management of tuberculosis, it has been documented to have some toxic effects in humans. Therefore, this study intends to investigate the modulatory effect of vitamins C and E on the hepatotoxicity, sperm quality and brain toxicity of Rifampicin. Forty Wistar albino rats were used, 10 animals per group. Group 1 animals received 0.3 mL of distilled water, the Group 2 animals received the therapeutic dose of rifampicin, Group 3 animals received therapeutic doses of rifampicin plus vitamin E, while Group 4 received therapeutic doses of rifampicin and vitamin C. The administration was performed orally during three months; the animals were sacrificed by cervical dislocation at the end of that period. Blood samples were collected and liver function and lipid profile was analyzed using fully automated clinical chemistry device. The liver, brain and reproductive organs underwent histopathological examination. Sperm samples were collected from the epididymis to achieve count and motility and morphological analysis. Results showed rifampicin alone to raise (p < 0.05) liver function enzymes (Aspartate amino transferase [AST], Serum alanine amino transferase [ALT] and Total Bilirubin) when compared with controls. While the vitamin E treated group showed remarkable protection, the vitamin C treated group showed questionable protection against the rifampicin induced liver damage. Sperm count results showed an important (p < 0.05) increase in the sperm quality in vitamin E and C treated groups. However, the vitamin E plus Rifampicin treated group showed increased lipid peroxidation. The histopathological findings revealed structural damages by rifampicin in liver, brain and epididymis while some remarkable architectural integrity was observed in the antioxidant-treated groups. It can be concluded that vitamin E or C improved sperm quality and protected against the brain damage caused by rifampicin. Moreover, vitamin E demonstrated remarkable hepatoprotection against rifampicin induced damage while vitamin C shows a questionable hepatoprotection.

Fusobacterium necrophorum causing infective endocarditis and liver and splenic abscesses

A 25-year-old male without prior co-morbidities was admitted to hospital with Fusobacterium necrophorum bacteremia, where he was found to have liver and splenic abscesses. Further evaluation with echocardiography revealed a bicuspid aortic valve with severe insufficiency and a 1.68 x 0.86 cm vegetation. The patient required abscess drainage, intravenous antimicrobial therapy and aortic valve replacement. Complete resolution of the infection was achieved after valve replacement and a prolonged course of intravenous antimicrobial therapy. A brief analysis of the patient's clinical course and review of the literature is presented.

Abdominal angiostrongyliasis with involvement of liver histopathologically confirmed: a case report

Human abdominal angiostrongyliasis is a zoonotic disease caused by ingestion of the L3 larvae of Angiostrongylus costaricensis. The human infection gives rise to a pathological condition characterized by acute abdominal pain, secondary to an inflammatory granulomatous reaction, marked eosinophilia and eosinophilic vasculitis. Most commonly this disease is limited to intestinal location, primary ileocecal, affecting the mesenteric arterial branches and intestinal walls. We present one of the few cases reported around the world with simultaneous involvement of the intestines and liver, including proved presence of nematodes inside the hepatic arteriole.

NATURAL INFECTION BY Trypanosoma cruzi IN ONE DOG IN CENTRAL WESTERN BRAZIL: A CASE REPORT

SUMMARY It is estimated that about 10 million people are infected with Trypanosoma cruzi worldwide, mostly in Latin America and more than 25 million are at risk of acquiring this infection in endemic areas. Dogs are an important reservoir for this pathogen and thus, considered a risk factor for human populations. This report describes one case of Chagas disease in a dog from Cuiabá, Mato Grosso State, Brazil. The diagnosis was obtained by direct examination of trypomastigote forms in blood smears. Amastigotes forms were visualized in microscopy of the bone marrow, lymph nodes, kidneys, liver and brain. The T. cruzi (ZIII) infection was confirmed by Polymerase Chain Reaction, and sequencing. The animal presented multisystemic failure and died. Although acute Chagas disease in humans is not reported in Cuiabá, this is the first report of a canine case in this region. This case represents a warning, to health professionals and authorities, to the possibility of transmission of this zoonosis in Cuiabá.

STUDY OF THE PREVALENCE OF Capillaria hepatica IN HUMANS AND RODENTS IN AN URBAN AREA OF THE CITY OF PORTO VELHO, RONDÔNIA, BRAZIL

Introduction: Hepatic capillariosis, caused by Capillaria hepatica (Calodium hepaticum) (Bancroft, 1893), Travassos, 1915 (Nematoda, Trichinelloidea, Capillariidae), is a common zoonosis in rodents but is rare in humans. Seventy-two cases in humans have been reported worldwide since the first case was described by MACARTHUR in 192417,27. This study aimed to determine the prevalence of Capillaria hepatica in humans and rodents in an urban area of Porto Velho, the capital of Rondônia, in Brazil. Methods: After conducting a census of the area, 490 residents were randomly selected, and, after signing a term of consent, provided blood samples that were screened for anti-Capillaria hepatica antibodies. Simultaneously, rats were captured to assess the prevalence of this parasite in rodents by histopathological examination in liver sections. Results: A prevalence of 1.8% was found among residents who had specific antibodies at a dilution of 1:150, indicating exposure to parasite eggs; 0.8% of the subjects also had positive titers at a dilution of 1:400, indicating true infection. The prevalence in rats was 2%. Conclusions: The prevalence of infection with this parasite among humans and rats was low. While the prevalence encountered among humans was within the limits reported in the literature, the prevalence among rodents was much lower.

FATAL DISSEMINATED CRYPTOCOCCOSIS WITH RENAL INVOLVEMENT IN AN HIV-INFECTED PATIENT

SUMMARY Introduction: We present a fatal case of disseminated cryptococcosis in a young man whose diagnosis of HIV infection was made at the time of admission to the emergency room. Case report: The patient was a twenty-three-year-old man, with a history of daily fever during one month associated with diarrhea, weight loss, headache, vomiting and generalized seizures. He also had a history of diabetes mellitus, alcoholism and drug addiction. Upon physical examination the patient was pale, disoriented and had periods of agitation. White blood cells count was 3,440/mm3 (5% lymphocytes), hemoglobin was 10g/dL, platelets were 83,000/ mm3. Creatinine was 0.7 mg/dL; urea 19 mg/dL; Na, K, and liver enzymes were within normal limits. Lactic dehydrogenase was 494 IU/L. Cerebrospinal fluid (CSF) analysis revealed 10 white blood cells/mm3 (58% neutrophils, 31% lymphocytes, 11% monocytes) and 2 red blood cells/mm3. India ink test revealed six Cryptococcus yeasts/mm3. CSF glucose was 122 mg/dL and protein was 36 mg/ dL. VDRL test was negative and anti-HIV test was positive. Intravenous hydration, insulin, phenytoin, fluconazole, pyrimethamine, sulfadiazine, folinic acid, and amphotericin B were started. The patient did not improve and became obtunded and hypotensive. He was intubated and put on mechanical respiration. He received vasoactive drugs and died less than 24 hours after admission. A postmortem examination was performed and revealed disseminated cryptococcosis, with severe involvement of the kidneys. Conclusion: Cryptococcosis, as a rule, is a systemic disease that affects mostly immunocompromised individuals, especially patients with AIDS. When diagnosed late in its course it has a very high mortality.

LIVER BIOPSY: IMPORTANCE OF SPECIMEN SIZE IN THE DIAGNOSIS AND STAGING OF CHRONIC VIRAL HEPATITIS

Liver biopsy is the gold standard method for the grading and staging of chronic viral hepatitis, but optimal biopsy specimen size remains controversial. The aim of this study was to evaluate the quality of liver specimen (number of portal tracts) and to evaluate the impact of the number of portal tracts in the staging of chronic hepatitis. Material and Methods: 468 liver biopsies from consecutive patients with hepatitis C virus and hepatitis B virus infection from 2009 to 2010 were evaluated. Results: The length of fragment was less than 10 mm in 43 cases (9.3%), between 10 and 14 mm in 114 (24.3%), and ≥ 15 mm in 311 (64.4%); of these, in 39 (8.3%) cases were ≥ 20 mm. The mean representation of portal tracts was 17.6 ± 2.1 (5-40); in specimens ≥ 15 mm the mean portal tract was 13.5 ± 4.7 and in cases ≤ 15 mm was 11.4 ± 5.0 (p = 0.002). Cases with less than 11 portal tracts were associated with F3, and cases with 11 or more portal tracts with F2 (p = 0.001). Conclusion: this study demonstrated the good quality of liver biopsy and a relationship between the macroscopic size of the fragment and the number of portal tracts.

Examination of mycological samples by means of the scanning electron microscope

Three species of Siphomycetes: Rhizopus arhizus, Rhizopus equinus and Rhizopus nigricans, as well as a Septomycete: Emericella nidulans, have been examined by means of a scanning electron microscope. Among the difjerent Rhizopus, this technique showed differences in the appearance of the sporangia. In Emericella nidulans, scanning microscopy enábled one to ascertain that the "Hull cells" were completely hollow and also demonstrated the ornemented aspect of the ascospores.

Liver function evaluation in leptospirosis with colloidal gold 1 9 8 Au

Eight patients with leptospirosis were studied with colloidal gold 1 9 8 Au. The radiocolloidal hepatic distribution was altered, presenting a non-homogeneous tiver concentration in seven cases, and a minute to moderate splenic visualization in five. Two patients presented doubtful splenic image, and one seemed to be normal. Liver scanning with colloidal gold 1 9 8 Au is demonstra ted to be a good liver function test.

Liver and serum soluble protein changes and pathomorphology in undernourished mice with acute Schistosomiasis mansoni

Body, liver and spleen weights; histopathology of the liver, spleen and intestines; hepatic and serum soluble proteins changes were the parameters studied in undernourished Swiss albino mice experimentally infected with S. mansoni. Non-infected deficient animab had lower liver/body weight and spleen/body weight ratios as compared to the controls (22.60% casein group). Infected mice showed higher values regardless the type of diet. Undernourished infected subgroup showed a persistent exudative periovular reaction in the liver. Soluble hepatic proteins content and serum protein fractions appeared to be lower in the deficient infected mice. A significant difference was detected in the gammaglobulin fraction between infected and non-infected animals fed the control diet with higher values for the former. Our data suggest that the effects of malnutrition, per se, are sometimes more detrimental to the host than those due to Manson 's schistosomiasis.

Serratia marcescens bacteremia associated with schistosomiasis mansoni

The case of a 21 -year-old man coming from rural Paraíba, northeastern Brazil, with schistosomiasis mansoni associated with Serratia marcescens bacteremia, is reported. His main complaints on admission were fever, diaphoresis and chills for ten days, and diarrhoea that lasted for four days. On physical examination he hadjaundice and hepatosplenomegaly. Diagnosis of S. marcescens bacteremia was made by isolation of the bacterium in blood culture, and schistosomiasis was diagnosed by rectal and liver biopsies. This is the first time that the association of S. marcescens bacteremia and schistosomiasis mansoni is recognized. Although our case does not fit into the classic definition of prolonged bacteremia associated with schistosomiasis, it can be considered as a mild form of this association. With the improvement of medical assistance and laboratory facilities, early diagnosis of this association will be made more frequently, cases with short duration will be diagnosed few days after the start of the symptoms, and classic prolonged cases will become rarer.