Lipid nanoparticles for amphotericin delivery in the treatment of American tegumentary leishmaniasis.

Leishmaniasis occurs in the five continents and represents a serious public health challenge, but is still a neglected disease, and the current pharmacological weaponry is far from satisfactory. Triglyceride-rich nanoparticles mimicking chylomicrons (TGNP) behave metabolically like native chylomicrons when injected into the bloodstream. Previously we have shown that TGNP as vehicle to amphothericin B (AB) for treatment of fungi infection showed reduced renal toxicity and lower animal death rates compared to conventional AB. The aim of the current study was to test the tolerability and effectiveness of the TGNP-AB preparation in a murine model of Leishmania amazonensis infection. The in vitro assays determined the cytotoxicity of TGNP-AB, AB, and TGNP in macrophages and promastigote forms and the leishmanicidal activity in infected macrophages. The in vivo toxicity tests were performed in healthy mice with increasing doses of TGPN-AB and AB. Then, animals were treated with 2.5 mg/kg/day of AB, 17.5 mg/kg/day of TGNP-AB, or TGNP three times a week for 4 weeks. TGNP-AB formulation was less cytotoxic for macrophages than AB. TGNP-AB was more effective than AB against the promastigotes forms of the parasite and more effective in reducing the number of infected macrophages and the number of amastigotes forms per cell. TGNP-AB-treated animals showed lower hepatotoxicity. In addition, TGNP-AB group showed a marked reduction in lesion size on the paws and parasitic load. The TGNP-AB preparation attained excellent leishmanicidal activity with remarkable lower drug toxicity at very high doses that, due to the toxicity-buffering properties of the nanocarrier, become fully tolerable.

Secondary Prophylaxis with Liposomal Amphotericin B in a Patient with Mucosal Leishmaniasis Undergoing Immunobiological Therapy for Active Ankylosing Spondylitis.

Immunosuppressive treatments for rheumatic diseases present special problems in areas endemic for chronic infectious diseases because of the possibility of reactivation. Leishmaniasis is a significant neglected tropical disease caused by different species of protozoan parasites within the genus Leishmania. Amastigotes live as intracellular parasites in a variety of mammalian cells, most notably within phagocytes such as macrophages, and residual parasites can persist even after treatment and healing of the lesions. We herein report a case of relapsing mucosal leishmaniasis after aggressive immunotherapy for ankylosing spondylitis, with requirement for secondary prophylaxis with amphotericin B to prevent reactivation. This approach can be necessary for patients from endemic areas of tegumentary leishmaniasis, who will undergo aggressive immunotherapy.

Severe Leptospirosis Features in the Spleen Indicate Cellular Immunosuppression Similar to That Found in Septic Shock.

Objectives: To compare microscopic and immunologic features in the spleens of patients who died of pulmonary hemorrhage and shock caused by leptospirosis (11 cases) or Gram-positive/-negative bacterial septic shock (10 cases) to those from control spleens (12 cases from splenectomy). Methodology: Histological features in the red pulp and white pulp were analyzed using archived samples by a semi quantitative score. Immunohistochemistry was used for the recognition of immune cell markers, cytokines, caspase-3 and Leptospira antigens. Results: The control group differed significantly from the leptospirosis and septic shock patients which demonstrate strong similarities: diffuse congestion in the red pulp with a moderate to intense infiltration of plasma cells and polymorphonuclear cells; follicles with marked atrophy; high density of CD20+ cells; low density of NK, TCD4+ and active caspase-3 positive cells and strong expression of IL-10; leptospirosis patients had higher S100 and TNF-α positive cells in the spleen than the other groups. Conclusion: The results suggest that an immunosuppressive state develops at the terminal stage of severe leptospirosis with pulmonary hemorrhage and shock similar to that of patients with septic shock, with diffuse endothelial activation in the spleen, splenitis, and signs of disturbance in the innate and adaptive immunity in the spleen. The presence of leptospiral antigens in 73% of the spleens of the leptospirosis patients suggests the etiological agent contributes directly to the pathogenesis of the lesions. Our results support therapeutic approaches involving antibiotic and immunomodulatory treatments for leptospirosis patients and suggest that leptospirosis patients, which are usually young men with no co-morbidities, form a good group for studying sepsis and septic shock.

The diagnosis of multiple opportunistic infections in advanced stage AIDS: when Ockham's Razor doesn't cut it.

In the advanced stage of AIDS, the diagnosis of the opportunistic infections may be challenging due to the high risk of performing invasive diagnostic methods in a patient with a critical clinical condition, as well as the correct interpretation of the results of microbiological exams. One of the challenges for the diagnosis and treatment of the opportunistic infections is that they may occur concomitantly in the same patient and they may mimic each other, leading to a high discrepancy between clinical and autopsy diagnoses. We describe the case of a 52-year-old man who was hospitalized because of weight loss, anemia, cough, and hepatosplenomegaly. During the investigation, the diagnosis of AIDS was made, and the patient developed respiratory failure and died on the fourth day of hospitalization. At autopsy, disseminated non-tuberculosis mycobacteriosis was found, affecting mainly the organs of the reticuloendothelial system. Also, severe and diffuse pneumonia caused by multiple agents (Pneumocystis jirovecii , Histoplasma capsulatum, suppurative bacterial infection, non-tuberculosis mycobacteria, and cytomegalovirus) was seen in a morphological pattern that could be called "collision pneumonia." The lesson from this case, revealed by the autopsy, is that in advanced AIDS, patients often have multiple opportunistic infections, so the principle of Ockham's razor-that a single diagnosis is most likely the best diagnosis-fails in this clinical context.

The diagnosis of multiple opportunistic infections in advanced stage AIDS: when Ockham's Razor doesn't cut it

In the advanced stage of AIDS, the diagnosis of the opportunistic infections may be challenging due to the high risk of performing invasive diagnostic methods in a patient with a critical clinical condition, as well as the correct interpretation of the results of microbiological exams. One of the challenges for the diagnosis and treatment of the opportunistic infections is that they may occur concomitantly in the same patient and they may mimic each other, leading to a high discrepancy between clinical and autopsy diagnoses. We describe the case of a 52-year-old man who was hospitalized because of weight loss, anemia, cough, and hepatosplenomegaly. During the investigation, the diagnosis of AIDS was made, and the patient developed respiratory failure and died on the fourth day of hospitalization. At autopsy, disseminated non-tuberculosis mycobacteriosis was found, affecting mainly the organs of the reticuloendothelial system. Also, severe and diffuse pneumonia caused by multiple agents (Pneumocystis jirovecii, Histoplasma capsulatum, suppurative bacterial infection, non-tuberculosis mycobacteria, and cytomegalovirus) was seen in a morphological pattern that could be called "collision pneumonia." The lesson from this case, revealed by the autopsy, is that in advanced AIDS, patients often have multiple opportunistic infections, so the principle of Ockham's razor­that a single diagnosis is most likely the best diagnosis­fails in this clinical context.

Disseminated toxoplasmosis in a patient with advanced acquired immunodeficiency syndrome.

Extracerebral toxoplasmosis, with pulmonary involvement and shock, is a rare form of toxoplasmosis in patients with advanced AIDS. It can mimic pneumocystosis, histoplasmosis, and disseminated tuberculosis, and should be considered in the differential diagnosis of causes of respiratory failure and fulminant disease in this group of individuals, especially in areas where the Toxoplasma gondii infection is highly prevalent and in those without proper use of antimicrobial prophylaxis. We report the case of a 46-year-old male patient who presented to the emergency department with uremia, requiring urgent dialysis. During the laboratorial investigation, the patient had confirmed HIV infection, with a low CD4+ peripheral T-cell count (74 cells/µL). During hospitalization, the patient presented drug-induced hepatitis due to trimethoprim/sulfamethoxazole in a prophylactic dose, requiring interruption of this medication. On the 55th day of hospitalization, the patient developed refractory shock and died. At the autopsy, disseminated toxoplasmosis with encephalitis and severe necrotizing pneumonia were diagnosed, with numerous tachyzoites in the areas of pulmonary necrosis.

Disseminated toxoplasmosis in a patient with advanced acquired immunodeficiency syndrome

Extracerebral toxoplasmosis, with pulmonary involvement and shock, is a rare form of toxoplasmosis in patients with advanced AIDS. It can mimic pneumocystosis, histoplasmosis, and disseminated tuberculosis, and should be considered in the differential diagnosis of causes of respiratory failure and fulminant disease in this group of individuals, especially in areas where the Toxoplasma gondii infection is highly prevalent and in those without proper use of antimicrobial prophylaxis. We report the case of a 46-year-old male patient who presented to the emergency department with uremia, requiring urgent dialysis. During the laboratorial investigation, the patient had confirmed HIV infection, with a low CD4+ peripheral T-cell count (74 cells/µL). During hospitalization, the patient presented drug-induced hepatitis due to trimethoprim/sulfamethoxazole in a prophylactic dose, requiring interruption of this medication. On the 55th day of hospitalization, the patient developed refractory shock and died. At the autopsy, disseminated toxoplasmosis with encephalitis and severe necrotizing pneumonia were diagnosed, with numerous tachyzoites in the areas of pulmonary necrosis.

Antimicrobial susceptibility of Brazilian Clostridium difficile strains determined by agar dilution and disk diffusion

Abstract Clostridium difficile is a leading cause of diarrhea in hospitalized patients worldwide. While metronidazole and vancomycin are the most prescribed antibiotics for the treatment of this infection, teicoplanin, tigecycline and nitazoxanide are alternatives drugs. Knowledge on the antibiotic susceptibility profiles is a basic step to differentiate recurrence from treatment failure due to antimicrobial resistance. Because C. difficile antimicrobial susceptibility is largely unknown in Brazil, we aimed to determine the profile of C. difficile strains cultivated from stool samples of inpatients with diarrhea and a positive toxin A/B test using both agar dilution and disk diffusion methods. All 50 strains tested were sensitive to metronidazole according to CLSI and EUCAST breakpoints with an MIC90 value of 2 μg/mL. Nitazoxanide and tigecycline were highly active in vitro against these strains with an MIC90 value of 0.125 μg/mL for both antimicrobials. The MIC90 were 4 μg/mL and 2 μg/mL for vancomycin and teicoplanin, respectively. A resistance rate of 8% was observed for moxifloxacin. Disk diffusion can be used as an alternative to screen for moxifloxacin resistance, nitazoxanide, tigecycline and metronidazole susceptibility, but it cannot be used for testing glycopeptides. Our results suggest that C. difficile strains from São Paulo city, Brazil, are susceptible to metronidazole and have low MIC90 values for most of the current therapeutic options available in Brazil.

Antimicrobial susceptibility of Brazilian Clostridium difficile strains determined by agar dilution and disk diffusion.

Clostridium difficile is a leading cause of diarrhea in hospitalized patients worldwide. While metronidazole and vancomycin are the most prescribed antibiotics for the treatment of this infection, teicoplanin, tigecycline and nitazoxanide are alternatives drugs. Knowledge on the antibiotic susceptibility profiles is a basic step to differentiate recurrence from treatment failure due to antimicrobial resistance. Because C. difficile antimicrobial susceptibility is largely unknown in Brazil, we aimed to determine the profile of C. difficile strains cultivated from stool samples of inpatients with diarrhea and a positive toxin A/B test using both agar dilution and disk diffusion methods. All 50 strains tested were sensitive to metronidazole according to CLSI and EUCAST breakpoints with an MIC90 value of 2µg/mL. Nitazoxanide and tigecycline were highly active in vitro against these strains with an MIC90 value of 0.125µg/mL for both antimicrobials. The MIC90 were 4µg/mL and 2µg/mL for vancomycin and teicoplanin, respectively. A resistance rate of 8% was observed for moxifloxacin. Disk diffusion can be used as an alternative to screen for moxifloxacin resistance, nitazoxanide, tigecycline and metronidazole susceptibility, but it cannot be used for testing glycopeptides. Our results suggest that C. difficile strains from São Paulo city, Brazil, are susceptible to metronidazole and have low MIC90 values for most of the current therapeutic options available in Brazil.

fosI Is a New Integron-Associated Gene Cassette Encoding Reduced Susceptibility to Fosfomycin.

In this work, we demonstrate that the fosI gene encodes a predicted small protein with 134 amino acids and determines reduced susceptibility to fosfomycin. It raised the MIC from 0.125 to 6 µg/ml when the pBRA100 plasmid was introduced into Escherichia coli TOP10 and to 16 µg/ml when the gene was cloned into the pBC_SK(-) vector and expressed in E. coli TOP10.

Frequency of Plasmid-Mediated AmpC ß-Lactamases in Escherichia coli Isolates from Urine Samples in São Paulo, Brazil.

Plasmid-mediated AmpC ß-lactamases (PMACBLs) in Enterobacteriaceae encode resistance to third-generation cephalosporins, and these can mediate carbapenem resistance when associated with porin loss. However, no standardized phenotypic method is available for detecting these enzymes in the clinical microbiology laboratory. Limited data are available concerning the frequency of PMACBLs in Enterobacteriaceae in Brazil. This study was conducted in response to an increased cefoxitin (CFO) resistance rate of 3.7% in Escherichia coli isolates from urine samples from patients with suspected urinary tract infections during 2010. We collected 2,266 E. coli isolates prospectively during January 2012. A total of 109 (4.8%) isolates were nonsusceptible to CFO. These strains were further examined using multiplex PCR for the presence of genes encoding PMACBLs and using inhibitor assays with CFO and ceftazidime (CAZ) disks with and without phenylboronic acid. Pulsed-field gel electrophoresis was used to evaluate clonal dissemination. Genes encoding PMACBLs were detected in 1.8% of the isolates from inpatients and 0.46% of isolates from outpatients. The most prevalent gene was blaCMY-2 and blaCMY-4 was also detected. The phenotypic analysis showed 100% sensitivity and specificity for CMY-2 and CMY-4 when CFO-resistant isolates with a minimum zone diameter difference of 5 mm for CAZ or CAZ and CFO were considered positive. Although most of the isolates were nonclonal, one clonal group with two isolates was observed. Thus, the most frequent PMACBL in E. coli from São Paulo, Brazil is CMY-2, and both clonal and plasmid-mediated dissemination occur.

The Bacterial Spectrum and Antimicrobial Susceptibility in Female Recurrent Urinary Tract Infection: How Different They Are From Sporadic Single Episodes?

OBJECTIVE: To analyze and compare the etiological uropathogens and the susceptibility profile findings on urine culture between sporadic cases of community-acquired, uncomplicated urinary tract infection (UTI) and recurrent UTI cases in women. MATERIALS AND METHODS: We retrospectively analyzed the clinical data of 1629 women with uncomplicated UTI evaluated at our hospital between January 2007 and December 2012. Patients were divided into 2 groups: (1) no recurrent UTI and (2) recurrent UTI. We analyzed the microbiological findings and compared susceptibility profiles between groups. RESULTS: A total of 420 women were included. Group 1 had 233 (55.5%) patients and group 2 had 187 (44.5%). Escherichia coli was the most common agent in both groups (76.4% and 74.3%, respectively; P = .625), whereas Staphylococcus saprophyticus (8.2%) was the second most common in group 1, and Enterococcus faecalis was the second most common in group 2 (8.0%). Nitrofurantoin was the only oral agent that maintained the susceptibility profile in both groups (87.1% and 88.7%, respectively; P = .883). For E coli infections, only nitrofurantoin and amoxicillin/clavulanate maintained susceptibility rates more than 90% in both groups. CONCLUSION: UTI episodes in patients with recurrent UTI had similar bacterial spectra, but different susceptibility profiles compared with those from patients with nonrecurrent infections. The susceptibility rate for nitrofurantoin in patients with recurrent UTI remained high and comparable to the observed in patients with sporadic UTI, reinforcing its indication for empirical treatment while waiting for urine culture results.

Rothia aeria endocarditis in a patient with a bicuspid aortic valve: case report

Rothia aeria is an uncommon pathogen mainly associated with endocarditis in case reports. In previous reports, endocarditis by R. aeria was complicated by central nervous system embolization. In the case we report herein, endocarditis by R. aeria was diagnosed after acute self-limited diarrhea. In addition to the common translocation of R. aeria from the oral cavity, we hypothesize the possibility of intestinal translocation. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and genetic sequencing are important tools that can contribute to early and more accurate etiologic diagnosis of severe infections caused by Gram-positive rods.

Cerebrospinal fluid shunt infection caused by Corynebacterium sp: case report and review.

BACKGROUND: A 36-year-old immunocompetent woman with a posterior fossa arteriovenous malformation (PF-AVM) and hydrocephalus presented with low fever and mental confusion 4 days after ventriculoperitoneal shunting (VPS). METHODS: Cerebrospinal fluid (CSF) and ventricular catheter tip cultures isolated Corynebacterium sp. Similar to previous cases in the literature, species determination was not possible. However, the antibiotic sensitivity profile of this isolate suggested Corynebacterium jeikeium. Conversion to external ventricular drainage (EVD) was done and intravenous vancomycin was administered for 21 days. RESULTS AND CONCLUSIONS: The patient showed progressive improvement. Since the first CSF shunt infection caused by Corynebacterium sp., 16 other cases in the literatures have been reported. Additionally, this study reports the difficulties in recognizing CSF shunt infection caused by this agent and the possible clinical or laboratory patterns as observed in the literature.

Rothia aeria endocarditis in a patient with a bicuspid aortic valve: case report.

Rothia aeria is an uncommon pathogen mainly associated with endocarditis in case reports. In previous reports, endocarditis by R. aeria was complicated by central nervous system embolization. In the case we report herein, endocarditis by R. aeria was diagnosed after acute self-limited diarrhea. In addition to the common translocation of R. aeria from the oral cavity, we hypothesize the possibility of intestinal translocation. Matrix-assisted laser desorption ionization-time of flight mass spectrometry and genetic sequencing are important tools that can contribute to early and more accurate etiologic diagnosis of severe infections caused by Gram-positive rods.

Reactivation of mucosal and cutaneous leishmaniasis in a renal transplanted patient.

Mucosal leishmaniasis (ML) is a chronic form of tegumentary leishmaniasis, which causes destructive lesions of nasal, pharyngeal, and laryngeal mucosa. We describe a case of leishmaniasis reactivation with simultaneous cutaneous and mucosal forms in a renal transplanted patient with no history of prior leishmaniasis. Reactivation after renal transplantation was not reported in Brazil. A 67-year-old woman receiving prednisone 20 mg/day, tacrolimus 1 mg/day, and mycophenolic acid 360 mg/day presented with nose edema with erythema and cutaneous lesions. Amastigotes were identified on biopsies and the polymerase chain reaction confirmed Leishmania (Viannia) braziliensis. The patient was treated with liposomal amphotericin B but died 3 weeks after as a result of bacterial septic shock. In conclusion, tegumentary leishmaniasis can reactivate with simultaneous cutaneous and mucosal forms in a renal transplanted patient during the immunosuppressant therapy.

Liposomal formulation of amphotericin B for the treatment of mucosal leishmaniasis in HIV-negative patients.

BACKGROUND: Studies assessing the efficacy of liposomal amphotericin B (LAB) in the treatment of patients with mucosal leishmaniasis (ML) are very scarce in the literature and an optimal dose regimen has not yet been defined. METHODS: We performed a retrospective and descriptive analysis from records of 16 patients with ML treated with LAB. The mean daily dose of LAB was 2.5 mg/kg/day. RESULTS: Healing of the lesion was observed in 14 (88%) of the 16 patients. The mean cumulative doses, excluding the two treatment failures, were 2265 mg and 33 mg/kg. CONCLUSION: Liposomal amphotericin B in the cumulative dose of 30 to 35 mg/kg was able to achieve 100% effectiveness.

Uncomplicated Urinary Tract Infections in Women in a Sao Paulo Quaternary Care Hospital: Bacterial Spectrum and Susceptibility Patterns.

Uncomplicated urinary tract infections (UTI) in women are very common. Regular analysis of bacterial flora is important to formulate updated guidelines. The objective of this study is to determine and compare the microbiology of UTIs and their susceptibility patterns in a quaternary care hospital. In a seven-year review, the urine culture results of 480 female patients with uncomplicated UTIs were analyzed. Patients were divided into three groups according to their diagnosis and treatment characteristics: Group 1, cystitis at outpatient basis; group 2, cystitis at the Emergency Unit; and group 3, pyelonephritis. Group 1 included older patients, with a higher incidence of concomitant diabetes mellitus and recurrent UTIs. E. coli was the most common pathogen, responsible for 75.1% of cases, mainly for pyelonephritis (87.3%). Of the oral antimicrobials tested for cystitis, amoxicillin/clavulanate and nitrofurantoin had the highest susceptibility profiles (84.4% and 87.3%, respectively). For E. coli only, their susceptibility profiles were as high as 90.8% and 97.4%, respectively. For pyelonephritis treatment, fluoroquinoles had a susceptibility profile <90%, while ceftriaxone and gentamicin had susceptibility >90%. Uncomplicated UTI treatment is becoming more challenging because the susceptibility profiles of oral antimicrobials are increasingly resistant. In our environment, cystitis can still be managed with nitrofurantoin. Uncomplicated pyelonephritis should be managed with ceftriaxone or gentamicin.

USEFULNESS OF kDNA PCR IN THE DIAGNOSIS OF VISCERAL LEISHMANIASIS REACTIVATION IN CO-INFECTED PATIENTS / Utilidade da kDNA PCR no diagnostico de reativacao de leishmaniose visceral em pacientes co-infectados sintomaticos

SUMMARY It is important to develop new methods for diagnosing relapses in the co-infection of visceral leishmaniasis (VL) and HIV to enable earlier detection using less invasive methods. We report a case of a co-infected patient who had relapses after VL treatment, where the qualitative kDNA PCR showed a good performance. The kDNA PCR seems to be a useful tool for diagnosing VL and may be a good marker for predicting VL relapses after treatment of co-infected patients with clinical symptoms of the disease. .

RESUMO É importante a pesquisa de novos métodos laboratoriais para o diagnóstico de recidivas em casos de co-infecção leishmaniose visceral (LV) e vírus da imunodeficiência humana (HIV), que permitam o diagnóstico precoce das recidivas, utilizando métodos menos invasivos. Descrevemos aqui, o caso de paciente co-infectada que apresentou recidivas após o tratamento da LV e onde a PCR qualitativa demonstrou bom desempenho. A kDNA PCR parece ser ferramenta útil para o diagnóstico de recidivas de LV após o tratamento em pacientes co-infectados com sintomas clínicos da doença. .