Michel Fernando Martínez-Reséndez

Activity of sertraline against Cryptococcus neoformans: in vitro and in vivo assays.

Cryptococcus neoformans infection is an important cause of meningitis in HIV/AIDS endemic regions. Antifungals for its management include amphotericin B, flucytosine, and fluconazole. Recently, treatment of this mycosis with sertraline has been studied with variable clinical outcomes. The aim of the study was to assess the in vitro antifungal effect of sertraline against clinical isolates of Cryptococcus spp. as well as its in vivo activity in a murine model of cryptococcal meningoencephalitis. The in vitro susceptibility to fluconazole, amphotericin B, voriconazole and sertraline of 153 Cryptococcus spp. strains were evaluated according to CLSI procedures. Fungal tissue burden, serum antigenaemia and histopathology, together with the therapeutic efficacy of amphotericin B (3 mg/kg), fluconazole (15 mg/kg), and sertraline (3, 10, and 15 mg/kg) were evaluated in mice intracranially inoculated with one isolate of Cryptococcus neoformans. All strains were susceptible to the antifungals studied and exhibited growth inhibition with sertraline at clinically relevant concentrations. Sertraline at a dose of 15 mg/kg reduced the fungal burden in the brain and spleen with an efficacy comparable to that of fluconazole. In conclusion, sertraline exhibited an excellent in vitro-in vivo anti-cryptococcal activity, representing a possible new alternative for the clinical management of meningeal cryptococcosis.

Influence of whole-body washing of critically ill patients with chlorhexidine on Acinetobacter baumannii isolates

BACKGROUND Acinetobacter baumannii is 1 of the most important nosocomial pathogens and the causative agent of numerous types of infections, especially in intensive care units (ICUs). Our aim was to evaluate the effect of 2% chlorhexidine gluconate (CHG) whole-body washing of ICU patients on A baumannii in a tertiary care hospital. METHODS During the 6-month intervention period, 327 patients were subjected to whole-body bath with 2% CHG-impregnated wipes. blaIMP (active on imipenem), blaVIM (Verona integron-encoded metallo-ß-lactamase), and blaoxacillinase (OXA) of A baumannii were typed. Isolates were genotyped by pulsed-field gel electrophoresis. Minimum inhibitory concentrations (MIC) to CHG were determined by the agar dilution method and drug susceptibility determined using the broth microdilution method. Biofilm formation was determined by crystal violet staining. RESULTS We analyzed 80 isolates during the baseline period and 69 isolates during the intervention period. There was a decrease in the MIC₅₀ and MIC₉₀ values for CHG for isolates (8 mg/L and 16 mg/L, respectively). All isolates typed positive for OXA₅₁-like and 86% typed positive for OXA₂₄-like pulsed-field gel electrophoresis identified 2 main clone types. During the intervention period the frequency of clone A decreased and that of clone B increased. Both clones were OXA₂₄-like positive. CONCLUSIONS The A baumannii isolates recovered from patients who received body washing with 2% CHG presented with a significant decrease in CHG MIC values associated with a change in clonality correlating with increased biofilm production.

Chlorhexidine whole-body washing of patients reduces methicillin-resistant Staphylococcus aureus and has a direct effect on the distribution of the ST5-MRSA-II (New York/Japan) clone

Purpose. Methicillin‐resistant Staphylococcus aureus (MRSA) colonizes the skin of hospitalized patients and is associated with high morbidity and mortality. To prevent colonization and infection by S. aureus, better disinfection practices are required. Therefore, we evaluated the effect of chlorhexidine whole‐body washing on hospital‐acquired S. aureus infections among intensive care unit (ICU) patients in a tertiary hospital in Mexico. Methodology. The study was conducted over 18 months to evaluate the effect of 2 % chlorhexidine gluconate (CXG) whole‐body washing of ICU adult patients on chlorhexidine and antibiotic resistance, biofilm production and clonal distribution of S. aureus in a tertiary care hospital. Minimum inhibitory concentrations for CXG, antibiotic susceptibility and biofilm production by S. aureus isolates were determined. Pulsed‐field gel electrophoresis, multilocus sequence typing (MLST) and PCR for Panton‐Valentine leucocidin (PVL) were used for molecular typing of MRSA isolates. Results/Key findings. We included 158 isolates. A reduction in antibiotic resistance in the study period was observed for clindamycin, levofloxacin, norfloxacin, oxacillin and trimethoprim/sulfamethoxazole. None of the isolates showed reduced susceptibility to CXG. Most of the isolates were non‐biofilm producers (147/158). The most commonly identified clone was a descendant of the ST5‐MRSA‐II (New York/Japan) clone. This clone decreased during the intervention period and reappeared markedly in the post‐intervention period. During the post‐intervention period, two isolates were related with the clone ST8‐MRSA‐IV (also known as USA300). Conclusion. Our findings suggest that the CXG bathing favored the reduction of healthcare‐associated MRSA isolates and a temporary reduction of the predominant ST5‐MRSA‐II (New York/Japan) clone.

An unusual case of Candida ciferrii fungemia in an immunocompromised patient with Crohn’s and Mycobacterium bovis disease

We present a case report of a fungal bloodstream infection due to an unusual pathogen. This is a 30 years-old female patient diagnosed with Crohns disease and a disseminated Mycobacterium bovis infection subsequently complicated by fungemia due to the emergent yeast pathogen Candida ciferrii, who was unresponsive to fluconazole and made a full recovery after treatment with posaconazole. To our knowledge, this is the first report of Candida ciferrii isolation from blood in an adult associated to a central venous catheter and which was successfully treated with posaconazole.

Outbreak of parvovirus B19 infection among anesthesiology and surgical fellows

A human parvovirus B19 outbreak was detected in personnel assigned to a surgical area (anesthesiology fellows and an otorhinolaryngology fellow) in a university hospital. The attack rate between susceptible members was higher than previous reports. Diagnosis was determined by polymerase chain reaction for human parvovirus B19 in serum of 1 subject and immunoglobulin M/immunoglobulin G antibody titer in the remaining subjects. Medical personnel were put on leave of absence until resolution of symptoms and laboratory confirmation of health. No cases of infection were detected in hospitalized patients or other health care workers on follow-up.

Purple urine bag syndrome in end-stage chronic kidney disease

INTRODUCTION When faced with violet, purple or purplish-blue urine, clinicians should consider urinary tract infection in their differential diagnosis. CASE REPORT A 60-year-old woman with end-stage kidney disease and non-adherence to renal replacement therapy was admitted to our hospital for placement of hemodialysis catheter. During her hospitalization she had purple urine, and purple urine bag syndrome (PUBS) was diagnosed. She was effectively treated with antibiotics and her urine returned to a dark yellow color. DISCUSSION Although this condition is often easily treated, diagnosing PUBS in chronic renal patients probably means an increased serum concentration of indoxyl sulfate, metabolite that is involved in the progression of both CKD and cardiovascular disease. CONCLUSION Hence, in the context of our renal patients, perhaps PUBS is not as benign as supposed.

Septic Pulmonary Emboli and Renal Abscess Caused by Staphylococcus aureus in an HIV-Infected Patient

Staphylococcus aureus is a common cause of bacteremia in the general population and can lead to serious metastatic infection particularly in immunocompromised persons. However, prompt diagnosis and management can result in favorable outcomes. In the following case report, the clinical course of an HIV-infected man is presented; he developed bloodstream infection (BSI) and associated complications: septic pulmonary embolism, right renal abscess, and ipsilateral renal vein thrombosis. Methicillin-resistant Staphylococcus aureus (MRSA) was identified as the cause of sepsis and successfully treated with surgery and antimicrobials. Intravenous vancomycin was the primary therapy, followed by oral linezolid after resolution of bacteremia.